116 results on '"A La Spada"'
Search Results
2. X-linked SBMA model mice display relevant non-neurological phenotypes and their expression of mutant androgen receptor protein in motor neurons is not required for neuromuscular disease.
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Gromova, Anastasia, Cha, Byeonggu, Robinson, Erica M, Strickland, Laura M, Nguyen, Nhat, ElMallah, Mai K, Cortes, Constanza J, and La Spada, Albert R
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Motor Neurons ,Animals ,Mice ,Transgenic ,Humans ,Mice ,Nerve Degeneration ,Receptors ,Androgen ,Phenotype ,Aged ,Male ,Bulbo-Spinal Atrophy ,X-Linked ,Rare Diseases ,Genetics ,Orphan Drug ,Neurodegenerative ,Neurosciences ,2.1 Biological and endogenous factors ,Aetiology ,Neurological ,Musculoskeletal ,Biochemistry and Cell Biology ,Clinical Sciences - Abstract
X-linked spinal and bulbar muscular atrophy (SBMA; Kennedy's disease) is a rare neuromuscular disorder characterized by adult-onset proximal muscle weakness and lower motor neuron degeneration. SBMA was the first human disease found to be caused by a repeat expansion mutation, as affected patients possess an expanded tract of CAG repeats, encoding polyglutamine, in the androgen receptor (AR) gene. We previously developed a conditional BAC fxAR121 transgenic mouse model of SBMA and used it to define a primary role for skeletal muscle expression of polyglutamine-expanded AR in causing the motor neuron degeneration. Here we sought to extend our understanding of SBMA disease pathophysiology and cellular basis by detailed examination and directed experimentation with the BAC fxAR121 mice. First, we evaluated BAC fxAR121 mice for non-neurological disease phenotypes recently described in human SBMA patients, and documented prominent non-alcoholic fatty liver disease, cardiomegaly, and ventricular heart wall thinning in aged male BAC fxAR121 mice. Our discovery of significant hepatic and cardiac abnormalities in SBMA mice underscores the need to evaluate human SBMA patients for signs of liver and heart disease. To directly examine the contribution of motor neuron-expressed polyQ-AR protein to SBMA neurodegeneration, we crossed BAC fxAR121 mice with two different lines of transgenic mice expressing Cre recombinase in motor neurons, and after updating characterization of SBMA phenotypes in our current BAC fxAR121 colony, we found that excision of mutant AR from motor neurons did not rescue neuromuscular or systemic disease. These findings further validate a primary role for skeletal muscle as the driver of SBMA motor neuronopathy and indicate that therapies being developed to treat patients should be delivered peripherally.
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- 2023
3. Clonally expanded CD8 T cells characterize amyotrophic lateral sclerosis-4
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Campisi, Laura, Chizari, Shahab, Ho, Jessica SY, Gromova, Anastasia, Arnold, Frederick J, Mosca, Lorena, Mei, Xueyan, Fstkchyan, Yesai, Torre, Denis, Beharry, Cindy, Garcia-Forn, Marta, Jiménez-Alcázar, Miguel, Korobeynikov, Vladislav A, Prazich, Jack, Fayad, Zahi A, Seldin, Marcus M, De Rubeis, Silvia, Bennett, Craig L, Ostrow, Lyle W, Lunetta, Christian, Squatrito, Massimo, Byun, Minji, Shneider, Neil A, Jiang, Ning, La Spada, Albert R, and Marazzi, Ivan
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Biomedical and Clinical Sciences ,Immunology ,ALS ,Rare Diseases ,Neurodegenerative ,Neurosciences ,Brain Disorders ,Genetics ,2.1 Biological and endogenous factors ,Aetiology ,Neurological ,Animals ,Mice ,Amyotrophic Lateral Sclerosis ,CD8-Positive T-Lymphocytes ,Clone Cells ,DNA Helicases ,Gene Knock-In Techniques ,Motor Neurons ,Multifunctional Enzymes ,Mutation ,RNA Helicases ,Humans ,General Science & Technology - Abstract
Amyotrophic lateral sclerosis (ALS) is a heterogenous neurodegenerative disorder that affects motor neurons and voluntary muscle control1. ALS heterogeneity includes the age of manifestation, the rate of progression and the anatomical sites of symptom onset. Disease-causing mutations in specific genes have been identified and define different subtypes of ALS1. Although several ALS-associated genes have been shown to affect immune functions2, whether specific immune features account for ALS heterogeneity is poorly understood. Amyotrophic lateral sclerosis-4 (ALS4) is characterized by juvenile onset and slow progression3. Patients with ALS4 show motor difficulties by the time that they are in their thirties, and most of them require devices to assist with walking by their fifties. ALS4 is caused by mutations in the senataxin gene (SETX). Here, using Setx knock-in mice that carry the ALS4-causative L389S mutation, we describe an immunological signature that consists of clonally expanded, terminally differentiated effector memory (TEMRA) CD8 T cells in the central nervous system and the blood of knock-in mice. Increased frequencies of antigen-specific CD8 T cells in knock-in mice mirror the progression of motor neuron disease and correlate with anti-glioma immunity. Furthermore, bone marrow transplantation experiments indicate that the immune system has a key role in ALS4 neurodegeneration. In patients with ALS4, clonally expanded TEMRA CD8 T cells circulate in the peripheral blood. Our results provide evidence of an antigen-specific CD8 T cell response in ALS4, which could be used to unravel disease mechanisms and as a potential biomarker of disease state.
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- 2022
4. Altered H3 histone acetylation impairs high-fidelity DNA repair to promote cerebellar degeneration in spinocerebellar ataxia type 7
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Switonski, Pawel M, Delaney, Joe R, Bartelt, Luke C, Niu, Chenchen, Ramos-Zapatero, Maria, Spann, Nathanael J, Alaghatta, Akshay, Chen, Toby, Griffin, Emily N, Bapat, Jaidev, Sopher, Bryce L, and La Spada, Albert R
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Biological Sciences ,Genetics ,Rare Diseases ,Eye Disease and Disorders of Vision ,Neurosciences ,Brain Disorders ,Neurodegenerative ,Human Genome ,Aetiology ,2.1 Biological and endogenous factors ,Neurological ,Acetylation ,Animals ,Ataxin-7 ,Cerebellar Diseases ,DNA Repair ,Female ,Histones ,Humans ,Male ,Mice ,Neurons ,Peptides ,Spinocerebellar Ataxias ,ChIP-seq ,DNA damage ,ataxin-7 ,cerebellum ,epigenetic dysregulation ,neurodegeneration ,polyglutamine ,repair ,spinocerebellar ataxia ,translocation ,Biochemistry and Cell Biology ,Medical Physiology ,Biological sciences - Abstract
A common mechanism in inherited ataxia is a vulnerability of DNA damage. Spinocerebellar ataxia type 7 (SCA7) is a CAG-polyglutamine-repeat disorder characterized by cerebellar and retinal degeneration. Polyglutamine-expanded ataxin-7 protein incorporates into STAGA co-activator complex and interferes with transcription by altering histone acetylation. We performed chromatic immunoprecipitation sequencing ChIP-seq on cerebellum from SCA7 mice and observed increased H3K9-promoter acetylation in DNA repair genes, resulting in increased expression. After detecting increased DNA damage in SCA7 cells, mouse primary cerebellar neurons, and patient stem-cell-derived neurons, we documented reduced homology-directed repair (HDR) and single-strand annealing (SSA). To evaluate repair at endogenous DNA in native chromosome context, we modified linear amplification-mediated high-throughput genome-wide translocation sequencing and found that DNA translocations are less frequent in SCA7 models, consistent with decreased HDR and SSA. Altered DNA repair function in SCA7 may predispose the subject to excessive DNA damage, leading to neuron demise and highlights DNA repair as a therapy target.
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- 2021
5. Reduced C9ORF72 function exacerbates gain of toxicity from ALS/FTD-causing repeat expansion in C9orf72
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Zhu, Qiang, Jiang, Jie, Gendron, Tania F, McAlonis-Downes, Melissa, Jiang, Lulin, Taylor, Amy, Diaz Garcia, Sandra, Ghosh Dastidar, Somasish, Rodriguez, Maria J, King, Patrick, Zhang, Yongjie, La Spada, Albert R, Xu, Huaxi, Petrucelli, Leonard, Ravits, John, Da Cruz, Sandrine, Lagier-Tourenne, Clotilde, and Cleveland, Don W
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Genetics ,Neurosciences ,Neurodegenerative ,Aging ,Orphan Drug ,Dementia ,Rare Diseases ,Alzheimer's Disease including Alzheimer's Disease Related Dementias (AD/ADRD) ,Brain Disorders ,Alzheimer's Disease Related Dementias (ADRD) ,Frontotemporal Dementia (FTD) ,ALS ,Acquired Cognitive Impairment ,2.1 Biological and endogenous factors ,Aetiology ,Neurological ,Amyotrophic Lateral Sclerosis ,Animals ,C9orf72 Protein ,DNA Repeat Expansion ,Female ,Frontotemporal Dementia ,Male ,Mice ,Mice ,Inbred C57BL ,Mice ,Transgenic ,Psychology ,Cognitive Sciences ,Neurology & Neurosurgery - Abstract
Hexanucleotide expansions in C9orf72, which encodes a predicted guanine exchange factor, are the most frequent genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Although repeat expansion has been established to generate toxic products, mRNAs encoding the C9ORF72 protein are also reduced in affected individuals. In this study, we tested how C9ORF72 protein levels affected repeat-mediated toxicity. In somatic transgenic mice expressing 66 GGGGCC repeats, inactivation of one or both endogenous C9orf72 alleles provoked or accelerated, respectively, early death. In mice expressing a C9orf72 transgene with 450 repeats that did not encode the C9ORF72 protein, inactivation of one or both endogenous C9orf72 alleles exacerbated cognitive deficits, hippocampal neuron loss, glial activation and accumulation of dipeptide-repeat proteins from translation of repeat-containing RNAs. Reduced C9ORF72 was shown to suppress repeat-mediated elevation in autophagy. These efforts support a disease mechanism in ALS/FTD resulting from reduced C9ORF72, which can lead to autophagy deficits, synergizing with repeat-dependent gain of toxicity.
- Published
- 2020
6. Autophagy gene haploinsufficiency drives chromosome instability, increases migration, and promotes early ovarian tumors.
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Delaney, Joe R, Patel, Chandni B, Bapat, Jaidev, Jones, Christian M, Ramos-Zapatero, Maria, Ortell, Katherine K, Tanios, Ralph, Haghighiabyaneh, Mina, Axelrod, Joshua, DeStefano, John W, Tancioni, Isabelle, Schlaepfer, David D, Harismendy, Olivier, La Spada, Albert R, and Stupack, Dwayne G
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Cell Line ,Tumor ,Animals ,Mice ,Ovarian Neoplasms ,Chromosomal Instability ,Microtubule-Associated Proteins ,Cell Movement ,Female ,Metabolome ,Haploinsufficiency ,Carcinogenesis ,Beclin-1 ,Ovarian Cancer ,Genetics ,Cancer ,Human Genome ,Breast Cancer ,Rare Diseases ,2.1 Biological and endogenous factors ,Developmental Biology - Abstract
Autophagy, particularly with BECN1, has paradoxically been highlighted as tumor promoting in Ras-driven cancers, but potentially tumor suppressing in breast and ovarian cancers. However, studying the specific role of BECN1 at the genetic level is complicated due to its genomic proximity to BRCA1 on both human (chromosome 17) and murine (chromosome 11) genomes. In human breast and ovarian cancers, the monoallelic deletion of these genes is often co-occurring. To investigate the potential tumor suppressor roles of two of the most commonly deleted autophagy genes in ovarian cancer, BECN1 and MAP1LC3B were knocked-down in atypical (BECN1+/+ and MAP1LC3B+/+) ovarian cancer cells. Ultra-performance liquid chromatography mass-spectrometry metabolomics revealed reduced levels of acetyl-CoA which corresponded with elevated levels of glycerophospholipids and sphingolipids. Migration rates of ovarian cancer cells were increased upon autophagy gene knockdown. Genomic instability was increased, resulting in copy-number alteration patterns which mimicked high grade serous ovarian cancer. We further investigated the causal role of Becn1 haploinsufficiency for oncogenesis in a MISIIR SV40 large T antigen driven spontaneous ovarian cancer mouse model. Tumors were evident earlier among the Becn1+/- mice, and this correlated with an increase in copy-number alterations per chromosome in the Becn1+/- tumors. The results support monoallelic loss of BECN1 as permissive for tumor initiation and potentiating for genomic instability in ovarian cancer.
- Published
- 2020
7. Mutant huntingtin impairs PNKP and ATXN3, disrupting DNA repair and transcription.
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Gao, Rui, Chakraborty, Anirban, Geater, Charlene, Pradhan, Subrata, Gordon, Kara L, Snowden, Jeffrey, Yuan, Subo, Dickey, Audrey S, Choudhary, Sanjeev, Ashizawa, Tetsuo, Ellerby, Lisa M, La Spada, Albert R, Thompson, Leslie M, Hazra, Tapas K, and Sarkar, Partha S
- Subjects
Cell Line ,Animals ,Mice ,Transgenic ,Humans ,DNA Repair Enzymes ,DNA-Directed RNA Polymerases ,Phosphotransferases (Alcohol Group Acceptor) ,Sialoglycoproteins ,Peptide Fragments ,Repressor Proteins ,DNA Repair ,Transcription ,Genetic ,Protein Binding ,Mutant Proteins ,Protein Multimerization ,Ataxin-3 ,Huntingtin Protein ,DNA damage ,DNA damage response ,Huntington's disease ,Transcription-Coupled DNA Repair ,mouse ,neuroscience ,polyglutamine ,Rare Diseases ,Genetics ,Brain Disorders ,Neurosciences ,Huntington's Disease ,Neurodegenerative ,Neurological ,Generic Health Relevance ,Biochemistry and Cell Biology - Abstract
How huntingtin (HTT) triggers neurotoxicity in Huntington's disease (HD) remains unclear. We report that HTT forms a transcription-coupled DNA repair (TCR) complex with RNA polymerase II subunit A (POLR2A), ataxin-3, the DNA repair enzyme polynucleotide-kinase-3'-phosphatase (PNKP), and cyclic AMP-response element-binding (CREB) protein (CBP). This complex senses and facilitates DNA damage repair during transcriptional elongation, but its functional integrity is impaired by mutant HTT. Abrogated PNKP activity results in persistent DNA break accumulation, preferentially in actively transcribed genes, and aberrant activation of DNA damage-response ataxia telangiectasia-mutated (ATM) signaling in HD transgenic mouse and cell models. A concomitant decrease in Ataxin-3 activity facilitates CBP ubiquitination and degradation, adversely impacting transcription and DNA repair. Increasing PNKP activity in mutant cells improves genome integrity and cell survival. These findings suggest a potential molecular mechanism of how mutant HTT activates DNA damage-response pro-degenerative pathways and impairs transcription, triggering neurotoxicity and functional decline in HD.
- Published
- 2019
8. Astroglial-targeted expression of the fragile X CGG repeat premutation in mice yields RAN translation, motor deficits and possible evidence for cell-to-cell propagation of FXTAS pathology.
- Author
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Wenzel, H Jürgen, Murray, Karl D, Haify, Saif N, Hunsaker, Michael R, Schwartzer, Jared J, Kim, Kyoungmi, La Spada, Albert R, Sopher, Bryce L, Hagerman, Paul J, Raske, Christopher, Severijnen, Lies-Anne WFM, Willemsen, Rob, Hukema, Renate K, and Berman, Robert F
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Astrocytes ,Animals ,Mice ,Inbred C57BL ,Mice ,Transgenic ,Mice ,Ataxia ,Tremor ,Fragile X Syndrome ,Motor Skills Disorders ,Cell Communication ,Gene Expression ,Trinucleotide Repeat Expansion ,Base Sequence ,Male ,Fragile X Mental Retardation Protein ,Electron microscopy of inclusions ,FMRpolyG ,FXTAS ,Fragile X premutation ,Glia ,Mouse model ,Neurodegeneration ,Non-cell-autonomous ,RAN translation ,Neurosciences ,Genetics ,Rare Diseases ,Neurodegenerative ,Brain Disorders ,Intellectual and Developmental Disabilities (IDD) ,Neurological ,Biochemistry and Cell Biology ,Clinical Sciences - Abstract
The fragile X premutation is a CGG trinucleotide repeat expansion between 55 and 200 repeats in the 5'-untranslated region of the fragile X mental retardation 1 (FMR1) gene. Human carriers of the premutation allele are at risk of developing the late-onset neurodegenerative disorder, fragile X-associated tremor/ataxia syndrome (FXTAS). Characteristic neuropathology associated with FXTAS includes intranuclear inclusions in neurons and astroglia. Previous studies recapitulated these histopathological features in neurons in a knock-in mouse model, but without significant astroglial pathology. To determine the role of astroglia in FXTAS, we generated a transgenic mouse line (Gfa2-CGG99-eGFP) that selectively expresses a 99-CGG repeat expansion linked to an enhanced green fluorescent protein (eGFP) reporter in astroglia throughout the brain, including cerebellar Bergmann glia. Behaviorally these mice displayed impaired motor performance on the ladder-rung test, but paradoxically better performance on the rotarod. Immunocytochemical analysis revealed that CGG99-eGFP co-localized with GFAP and S-100ß, but not with NeuN, Iba1, or MBP, indicating that CGG99-eGFP expression is specific to astroglia. Ubiquitin-positive intranuclear inclusions were found in eGFP-expressing glia throughout the brain. In addition, intracytoplasmic ubiquitin-positive inclusions were found outside the nucleus in distal astrocyte processes. Intriguingly, intranuclear inclusions, in the absence of eGFP mRNA and eGFP fluorescence, were present in neurons of the hypothalamus and neocortex. Furthermore, intranuclear inclusions in both neurons and astrocytes displayed immunofluorescent labeling for the polyglycine peptide FMRpolyG, implicating FMRpolyG in the pathology found in Gfa2-CGG99 mice. Considered together, these results show that Gfa2-CGG99 expression in mice is sufficient to induce key features of FXTAS pathology, including formation of intranuclear inclusions, translation of FMRpolyG, and deficits in motor function.
- Published
- 2019
9. Metabolic and Organelle Morphology Defects in Mice and Human Patients Define Spinocerebellar Ataxia Type 7 as a Mitochondrial Disease
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Ward, Jacqueline M, Stoyas, Colleen A, Switonski, Pawel M, Ichou, Farid, Fan, Weiwei, Collins, Brett, Wall, Christopher E, Adanyeguh, Isaac, Niu, Chenchen, Sopher, Bryce L, Kinoshita, Chizuru, Morrison, Richard S, Durr, Alexandra, Muotri, Alysson R, Evans, Ronald M, Mochel, Fanny, and La Spada, Albert R
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Biochemistry and Cell Biology ,Biological Sciences ,Rare Diseases ,Neurodegenerative ,Brain Disorders ,Neurosciences ,Stem Cell Research ,Genetics ,Aetiology ,2.1 Biological and endogenous factors ,Neurological ,Adipose Tissue ,Animals ,Ataxin-7 ,Blood Glucose ,Energy Metabolism ,Humans ,Kynurenine ,Metabolomics ,Mice ,Mitochondria ,Mitochondrial Diseases ,NAD ,Neural Stem Cells ,Organelles ,Peptides ,Phenotype ,Purkinje Cells ,Reproducibility of Results ,Spinocerebellar Ataxias ,Trinucleotide Repeat Expansion ,Tryptophan ,Purkinje cell ,ataxin-7 ,induced pluripotent stem cells ,mitochondria ,mouse model ,nicotinamide adenine dinucleotide ,oxidative metabolism ,polyglutamine ,spinocerebellar ataxia ,trinucleotide repeat ,Medical Physiology ,Biological sciences - Abstract
Spinocerebellar ataxia type 7 (SCA7) is a retinal-cerebellar degenerative disorder caused by CAG-polyglutamine (polyQ) repeat expansions in the ataxin-7 gene. As many SCA7 clinical phenotypes occur in mitochondrial disorders, and magnetic resonance spectroscopy of patients revealed altered energy metabolism, we considered a role for mitochondrial dysfunction. Studies of SCA7 mice uncovered marked impairments in oxygen consumption and respiratory exchange. When we examined cerebellar Purkinje cells in mice, we observed mitochondrial network abnormalities, with enlarged mitochondria upon ultrastructural analysis. We developed stem cell models from patients and created stem cell knockout rescue systems, documenting mitochondrial morphology defects, impaired oxidative metabolism, and reduced expression of nicotinamide adenine dinucleotide (NAD+) production enzymes in SCA7 models. We observed NAD+ reductions in mitochondria of SCA7 patient NPCs using ratiometric fluorescent sensors and documented alterations in tryptophan-kynurenine metabolism in patients. Our results indicate that mitochondrial dysfunction, stemming from decreased NAD+, is a defining feature of SCA7.
- Published
- 2019
10. Overriding FUS autoregulation in mice triggers gain-of-toxic dysfunctions in RNA metabolism and autophagy-lysosome axis
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Ling, Shuo-Chien, Dastidar, Somasish Ghosh, Tokunaga, Seiya, Ho, Wan Yun, Lim, Kenneth, Ilieva, Hristelina, Parone, Philippe A, Tyan, Sheue-Houy, Tse, Tsemay M, Chang, Jer-Cherng, Platoshyn, Oleksandr, Bui, Ngoc B, Bui, Anh, Vetto, Anne, Sun, Shuying, McAlonis-Downes, Melissa, Han, Joo Seok, Swing, Debbie, Kapeli, Katannya, Yeo, Gene W, Tessarollo, Lino, Marsala, Martin, Shaw, Christopher E, Tucker-Kellogg, Greg, La Spada, Albert R, Lagier-Tourenne, Clotilde, Da Cruz, Sandrine, and Cleveland, Don W
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Biological Sciences ,Bioinformatics and Computational Biology ,Neurodegenerative ,Rare Diseases ,ALS ,Genetics ,Brain Disorders ,Neurosciences ,2.1 Biological and endogenous factors ,Aetiology ,Neurological ,Animals ,Autophagy ,Gene Expression Profiling ,Homeostasis ,Humans ,Lysosomes ,Mice ,Inbred C57BL ,Mutant Proteins ,RNA ,RNA-Binding Protein FUS ,FUS ,RNA metabolism ,amyotrophic lateral sclerosis ,autophagy-lysosome ,frontotemporal degeneration ,homeostasis ,mouse ,neuroscience ,Biochemistry and Cell Biology ,Biological sciences ,Biomedical and clinical sciences ,Health sciences - Abstract
Mutations in coding and non-coding regions of FUS cause amyotrophic lateral sclerosis (ALS). The latter mutations may exert toxicity by increasing FUS accumulation. We show here that broad expression within the nervous system of wild-type or either of two ALS-linked mutants of human FUS in mice produces progressive motor phenotypes accompanied by characteristic ALS-like pathology. FUS levels are autoregulated by a mechanism in which human FUS downregulates endogenous FUS at mRNA and protein levels. Increasing wild-type human FUS expression achieved by saturating this autoregulatory mechanism produces a rapidly progressive phenotype and dose-dependent lethality. Transcriptome analysis reveals mis-regulation of genes that are largely not observed upon FUS reduction. Likely mechanisms for FUS neurotoxicity include autophagy inhibition and defective RNA metabolism. Thus, our results reveal that overriding FUS autoregulation will trigger gain-of-function toxicity via altered autophagy-lysosome pathway and RNA metabolism function, highlighting a role for protein and RNA dyshomeostasis in FUS-mediated toxicity.
- Published
- 2019
11. Senataxin mutations elicit motor neuron degeneration phenotypes and yield TDP-43 mislocalization in ALS4 mice and human patients
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Bennett, Craig L, Dastidar, Somasish G, Ling, Shuo-Chien, Malik, Bilal, Ashe, Travis, Wadhwa, Mandheer, Miller, Derek B, Lee, Changwoo, Mitchell, Matthew B, van Es, Michael A, Grunseich, Christopher, Chen, Yingzhang, Sopher, Bryce L, Greensmith, Linda, Cleveland, Don W, and La Spada, Albert R
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Biomedical and Clinical Sciences ,Neurosciences ,Neurodegenerative ,ALS ,Brain Disorders ,Genetics ,Rare Diseases ,2.1 Biological and endogenous factors ,Aetiology ,Neurological ,Amyotrophic Lateral Sclerosis ,Animals ,DNA Helicases ,DNA-Binding Proteins ,Female ,Humans ,Male ,Mice ,Motor Neurons ,Multifunctional Enzymes ,Nerve Degeneration ,Phenotype ,RNA Helicases ,Amyotrophic lateral sclerosis ,Senataxin ,Transgenesis ,Gene targeting ,TDP-43 ,Nucleocytoplasmic transport ,Ran ,RanGAP1 ,Motor neuron ,Neurodegeneration ,Clinical Sciences ,Neurology & Neurosurgery - Abstract
Amyotrophic lateral sclerosis type 4 (ALS4) is a rare, early-onset, autosomal dominant form of ALS, characterized by slow disease progression and sparing of respiratory musculature. Dominant, gain-of-function mutations in the senataxin gene (SETX) cause ALS4, but the mechanistic basis for motor neuron toxicity is unknown. SETX is a RNA-binding protein with a highly conserved helicase domain, but does not possess a low-complexity domain, making it unique among ALS-linked disease proteins. We derived ALS4 mouse models by expressing two different senataxin gene mutations (R2136H and L389S) via transgenesis and knock-in gene targeting. Both approaches yielded SETX mutant mice that develop neuromuscular phenotypes and motor neuron degeneration. Neuropathological characterization of SETX mice revealed nuclear clearing of TDP-43, accompanied by TDP-43 cytosolic mislocalization, consistent with the hallmark pathology observed in human ALS patients. Postmortem material from ALS4 patients exhibited TDP-43 mislocalization in spinal cord motor neurons, and motor neurons from SETX ALS4 mice displayed enhanced stress granule formation. Immunostaining analysis for nucleocytoplasmic transport proteins Ran and RanGAP1 uncovered nuclear membrane abnormalities in the motor neurons of SETX ALS4 mice, and nuclear import was delayed in SETX ALS4 cortical neurons, indicative of impaired nucleocytoplasmic trafficking. SETX ALS4 mice thus recapitulated ALS disease phenotypes in association with TDP-43 mislocalization and provided insight into the basis for TDP-43 histopathology, linking SETX dysfunction to common pathways of ALS motor neuron degeneration.
- Published
- 2018
12. The replicative lifespan‐extending deletion of SGF73 results in altered ribosomal gene expression in yeast
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Mason, Amanda G, Garza, Renee M, McCormick, Mark A, Patel, Bhumil, Kennedy, Brian K, Pillus, Lorraine, and La Spada, Albert R
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Biochemistry and Cell Biology ,Biological Sciences ,Genetics ,Neurodegenerative ,Brain Disorders ,Rare Diseases ,Aetiology ,2.1 Biological and endogenous factors ,Acetylation ,Ataxin-7 ,Base Sequence ,Binding Sites ,Cell Division ,Gene Deletion ,Gene Expression Regulation ,Fungal ,Histone Acetyltransferases ,Humans ,Microbial Viability ,Molecular Sequence Annotation ,Promoter Regions ,Genetic ,Protein Binding ,Ribosomal Proteins ,Saccharomyces cerevisiae ,Saccharomyces cerevisiae Proteins ,Sequence Homology ,Amino Acid ,Signal Transduction ,Spinocerebellar Ataxias ,Trans-Activators ,genome-wide occupancy ,longevity gene ,Neurodegeneration ,replicative lifespan ,Sgf73 ,yeast ,Medical and Health Sciences ,Developmental Biology ,Biological sciences ,Biomedical and clinical sciences - Abstract
Sgf73, a core component of SAGA, is the yeast orthologue of ataxin-7, which undergoes CAG-polyglutamine repeat expansion leading to the human neurodegenerative disease spinocerebellar ataxia type 7 (SCA7). Deletion of SGF73 dramatically extends replicative lifespan (RLS) in yeast. To further define the basis for Sgf73-mediated RLS extension, we performed ChIP-Seq, identified 388 unique genomic regions occupied by Sgf73, and noted enrichment in promoters of ribosomal protein (RP)-encoding genes. Of 388 Sgf73 binding sites, 33 correspond to 5' regions of genes implicated in RLS extension, including 20 genes encoding RPs. Furthermore, half of Sgf73-occupied, RLS-linked RP genes displayed significantly reduced expression in sgf73Δ mutants, and double null strains lacking SGF73 and a Sgf73-regulated, RLS-linked RP gene exhibited no further increase in replicative lifespan. We also found that sgf73Δ mutants display altered acetylation of Ifh1, an important regulator of RP gene transcription. These findings implicate altered ribosomal protein expression in sgf73Δ yeast RLS and highlight altered acetylation as a pathway of relevance for SCA7 neurodegeneration.
- Published
- 2017
13. SUMOylated Senataxin functions in genome stability, RNA degradation, and stress granule disassembly, and is linked with inherited ataxia and motor neuron disease
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Craig L. Bennett and Albert R. La Spada
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53BP1 ,ALS4 ,AOA2 ,helicase ,nucleolus ,Senataxin ,Genetics ,QH426-470 - Abstract
Abstract Background Senataxin (SETX) is a DNA/RNA helicase critical for neuron survival. SETX mutations underlie two inherited neurodegenerative diseases: Ataxia with Oculomotor Apraxia type 2 (AOA2) and Amyotrophic Lateral Sclerosis type 4 (ALS4). Methods This review examines SETX key cellular processes and we hypothesize that SETX requires SUMO posttranslational modification to function properly. Results SETX is localized to distinct foci during S‐phase of the cell cycle, and these foci represent sites of DNA polymerase/RNA polymerase II (RNAP) collision, as they co‐localize with DNA damage markers 53BP1 and H2AX. At such sites, SETX directs incomplete RNA transcripts to the nuclear exosome for degradation via interaction with exosome component 9 (Exosc9), a key component of the nuclear exosome. These processes require SETX SUMOylation. SETX was also recently localized within stress granules (SGs), and found to regulate SG disassembly, a process that similarly requires SUMOylation. Conclusion SETX undergoes SUMO modification to function at S‐phase foci in cycling cells to facilitate RNA degradation. SETX may regulate similar processes in non‐dividing neurons at sites of RNAP II bidirectional self‐collision. Finally, SUMOylation of SETX appears to be required for SG disassembly. This SETX function may be crucial for neuron survival, as altered SG dynamics are linked to ALS disease pathogenesis. In addition, AOA2 point mutations have been shown to block SETX SUMOylation. Such mutations induce an ataxia phenotype indistinguishable from those with SETX null mutation, underscoring the importance of this modification.
- Published
- 2021
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14. The SAGA Histone Deubiquitinase Module Controls Yeast Replicative Lifespan via Sir2 Interaction
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McCormick, Mark A, Mason, Amanda G, Guyenet, Stephan J, Dang, Weiwei, Garza, Renee M, Ting, Marc K, Moller, Rick M, Berger, Shelley L, Kaeberlein, Matt, Pillus, Lorraine, La Spada, Albert R, and Kennedy, Brian K
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Biochemistry and Cell Biology ,Biological Sciences ,Neurodegenerative ,Genetics ,Brain Disorders ,Aging ,1.1 Normal biological development and functioning ,Underpinning research ,Generic health relevance ,Cell Proliferation ,DNA Replication ,Endopeptidases ,Histone Acetyltransferases ,Protein Binding ,Saccharomyces cerevisiae ,Saccharomyces cerevisiae Proteins ,Silent Information Regulator Proteins ,Saccharomyces cerevisiae ,Sirtuin 2 ,Trans-Activators ,Medical Physiology ,Biological sciences - Abstract
We have analyzed the yeast replicative lifespan of a large number of open reading frame (ORF) deletions. Here, we report that strains lacking genes SGF73, SGF11, and UBP8 encoding SAGA/SLIK complex histone deubiquitinase module (DUBm) components are exceptionally long lived. Strains lacking other SAGA/SALSA components, including the acetyltransferase encoded by GCN5, are not long lived; however, these genes are required for the lifespan extension observed in DUBm deletions. Moreover, the SIR2-encoded histone deacetylase is required, and we document both a genetic and physical interaction between DUBm and Sir2. A series of studies assessing Sir2-dependent functions lead us to propose that DUBm strains are exceptionally long lived because they promote multiple prolongevity events, including reduced rDNA recombination and altered silencing of telomere-proximal genes. Given that ataxin-7, the human Sgf73 ortholog, causes the neurodegenerative disease spinocerebellar ataxia type 7, our findings indicate that the genetic and epigenetic interactions between DUBm and SIR2 will be relevant to neurodegeneration and aging.
- Published
- 2014
15. Muscle Expression of Mutant Androgen Receptor Accounts for Systemic and Motor Neuron Disease Phenotypes in Spinal and Bulbar Muscular Atrophy
- Author
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Cortes, Constanza J, Ling, Shuo-Chien, Guo, Ling T, Hung, Gene, Tsunemi, Taiji, Ly, Linda, Tokunaga, Seiya, Lopez, Edith, Sopher, Bryce L, Bennett, C Frank, Shelton, G Diane, Cleveland, Don W, and La Spada, Albert R
- Subjects
Medical Physiology ,Biomedical and Clinical Sciences ,Neurodegenerative ,Genetics ,Rare Diseases ,Neurosciences ,Orphan Drug ,Brain Disorders ,Biotechnology ,Aetiology ,2.1 Biological and endogenous factors ,Neurological ,Musculoskeletal ,Actins ,Age Factors ,Animals ,Body Weight ,Brain ,Disease Models ,Animal ,Disease Progression ,Gene Expression Regulation ,Humans ,Male ,Mice ,Mice ,Transgenic ,Motor Neurons ,Movement Disorders ,Muscle Strength ,Muscle ,Skeletal ,Muscular Disorders ,Atrophic ,Peptides ,Phenotype ,Receptors ,Androgen ,Psychology ,Cognitive Sciences ,Neurology & Neurosurgery ,Biological psychology - Abstract
X-linked spinal and bulbar muscular atrophy (SBMA) is characterized by adult-onset muscle weakness and lower motor neuron degeneration. SBMA is caused by CAG-polyglutamine (polyQ) repeat expansions in the androgen receptor (AR) gene. Pathological findings include motor neuron loss, with polyQ-AR accumulation in intranuclear inclusions. SBMA patients exhibit myopathic features, suggesting a role for muscle in disease pathogenesis. To determine the contribution of muscle, we developed a BAC mouse model featuring a floxed first exon to permit cell-type-specific excision of human AR121Q. BAC fxAR121 mice develop systemic and neuromuscular phenotypes, including shortened survival. After validating termination of AR121 expression and full rescue with ubiquitous Cre, we crossed BAC fxAR121 mice with Human Skeletal Actin-Cre mice. Muscle-specific excision prevented weight loss, motor phenotypes, muscle pathology, and motor neuronopathy and dramatically extended survival. Our results reveal a crucial role for muscle expression of polyQ-AR in SBMA and suggest muscle-directed therapies as effective treatments.
- Published
- 2014
16. Tight expression regulation of senataxin, linked to motor neuron disease and ataxia, is required to avert cell-cycle block and nucleolus disassembly
- Author
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Craig L. Bennett, Bryce L. Sopher, and Albert R. La Spada
- Subjects
Cell biology ,Genetics ,Neuroscience ,Infectious disease ,Gene expression ,Gene regulation ,Science (General) ,Q1-390 ,Social sciences (General) ,H1-99 - Abstract
The Senataxin (SETX) protein exhibits strong sequence conservation with the helicase domain of the yeast protein Sen1p, and recessive SETX mutations cause a severe ataxia, known as Ataxia with Oculomotor Apraxia type 2, while dominant SETX mutations cause Amyotrophic Lateral Sclerosis type 4. SETX is a very low abundance protein, and its expression is tightly regulated, such that large increases in mRNA levels fail to significantly increase protein levels. Despite this, transient transfection in cell culture can boost SETX protein levels on an individual cell basis. Here we found that over-expression of normal SETX, but not enzymatically-dead SETX, is associated with S-phase cell-cycle arrest in HEK293A cells. As SETX interacts with the nuclear exosome to ensure degradation of incomplete RNA transcripts, and SETX localizes to sites of collision between the DNA replication machinery and the RNAP II complex, altered dosage or aberrant function of SETX may impede this process to promote S-phase cell-cycle arrest. Because neurons are enriched for long transcripts with additional antisense regulatory transcription, collisions of RNAP II complexes may occur in such post-mitotic cells, underscoring a role for SETX in maintaining neuron homeostasis.
- Published
- 2020
- Full Text
- View/download PDF
17. Autophagy gene haploinsufficiency drives chromosome instability, increases migration, and promotes early ovarian tumors.
- Author
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Joe R Delaney, Chandni B Patel, Jaidev Bapat, Christian M Jones, Maria Ramos-Zapatero, Katherine K Ortell, Ralph Tanios, Mina Haghighiabyaneh, Joshua Axelrod, John W DeStefano, Isabelle Tancioni, David D Schlaepfer, Olivier Harismendy, Albert R La Spada, and Dwayne G Stupack
- Subjects
Genetics ,QH426-470 - Abstract
Autophagy, particularly with BECN1, has paradoxically been highlighted as tumor promoting in Ras-driven cancers, but potentially tumor suppressing in breast and ovarian cancers. However, studying the specific role of BECN1 at the genetic level is complicated due to its genomic proximity to BRCA1 on both human (chromosome 17) and murine (chromosome 11) genomes. In human breast and ovarian cancers, the monoallelic deletion of these genes is often co-occurring. To investigate the potential tumor suppressor roles of two of the most commonly deleted autophagy genes in ovarian cancer, BECN1 and MAP1LC3B were knocked-down in atypical (BECN1+/+ and MAP1LC3B+/+) ovarian cancer cells. Ultra-performance liquid chromatography mass-spectrometry metabolomics revealed reduced levels of acetyl-CoA which corresponded with elevated levels of glycerophospholipids and sphingolipids. Migration rates of ovarian cancer cells were increased upon autophagy gene knockdown. Genomic instability was increased, resulting in copy-number alteration patterns which mimicked high grade serous ovarian cancer. We further investigated the causal role of Becn1 haploinsufficiency for oncogenesis in a MISIIR SV40 large T antigen driven spontaneous ovarian cancer mouse model. Tumors were evident earlier among the Becn1+/- mice, and this correlated with an increase in copy-number alterations per chromosome in the Becn1+/- tumors. The results support monoallelic loss of BECN1 as permissive for tumor initiation and potentiating for genomic instability in ovarian cancer.
- Published
- 2020
- Full Text
- View/download PDF
18. Clonally expanded CD8 T cells characterize amyotrophic lateral sclerosis-4
- Author
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Laura Campisi, Shahab Chizari, Jessica S. Y. Ho, Anastasia Gromova, Frederick J. Arnold, Lorena Mosca, Xueyan Mei, Yesai Fstkchyan, Denis Torre, Cindy Beharry, Marta Garcia-Forn, Miguel Jiménez-Alcázar, Vladislav A. Korobeynikov, Jack Prazich, Zahi A. Fayad, Marcus M. Seldin, Silvia De Rubeis, Craig L. Bennett, Lyle W. Ostrow, Christian Lunetta, Massimo Squatrito, Minji Byun, Neil A. Shneider, Ning Jiang, Albert R. La Spada, and Ivan Marazzi
- Subjects
Motor Neurons ,Multidisciplinary ,General Science & Technology ,Amyotrophic Lateral Sclerosis ,DNA Helicases ,Neurosciences ,CD8-Positive T-Lymphocytes ,Neurodegenerative ,Multifunctional Enzymes ,Article ,Clone Cells ,Brain Disorders ,Mice ,Rare Diseases ,Mutation ,Neurological ,Genetics ,Animals ,2.1 Biological and endogenous factors ,Gene Knock-In Techniques ,ALS ,Aetiology ,RNA Helicases - Abstract
Amyotrophic lateral sclerosis (ALS) is a heterogenous neurodegenerative disorder that affects motor neurons and voluntary muscle control1. ALS heterogeneity includes the age of manifestation, the rate of progression and the anatomical sites of symptom onset. Disease-causing mutations in specific genes have been identified and define different subtypes of ALS1. Although several ALS-associated genes have been shown to affect immune functions2, whether specific immune features account for ALS heterogeneity is poorly understood. Amyotrophic lateral sclerosis-4 (ALS4) is characterized by juvenile onset and slow progression3. Patients with ALS4 show motor difficulties by the time that they are in their thirties, and most of them require devices to assist with walking by their fifties. ALS4 is caused by mutations in the senataxin gene (SETX). Here, using Setx knock-in mice that carry the ALS4-causative L389S mutation, we describe an immunological signature that consists of clonally expanded, terminally differentiated effector memory (TEMRA) CD8 T cells in the central nervous system and the blood of knock-in mice. Increased frequencies of antigen-specific CD8 T cells in knock-in mice mirror the progression of motor neuron disease and correlate with anti-glioma immunity. Furthermore, bone marrow transplantation experiments indicate that the immune system has a key role in ALS4 neurodegeneration. In patients with ALS4, clonally expanded TEMRA CD8 T cells circulate in the peripheral blood. Our results provide evidence of an antigen-specific CD8 T cell response in ALS4, which could be used to unravel disease mechanisms and as a potential biomarker of disease state.
- Published
- 2022
19. Ataxin-3, DNA damage repair, and SCA3 cerebellar degeneration: on the path to parsimony?
- Author
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Jacqueline M Ward and Albert R La Spada
- Subjects
Genetics ,QH426-470 - Published
- 2015
- Full Text
- View/download PDF
20. Epigenetic and transcriptional modulation of WDR5 , a chromatin remodeling protein, in Huntington's disease human induced pluripotent stem cell (hiPSC) model
- Author
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Ida Biunno, Aikaterini Ntai, Andrea Barbieri, Angela Bentivegna, Gloria Saccani Jotti, Simona Baronchelli, Pasquale De Blasio, Paola Conforti, Alberto La Spada, Serena Redaelli, Baronchelli, S, La Spada, A, Ntai, A, Barbieri, A, Conforti, P, Jotti, G, Redaelli, S, Bentivegna, A, De Blasio, P, and Biunno, I
- Subjects
0301 basic medicine ,Disease modifying gene ,Cellular differentiation ,Induced Pluripotent Stem Cells ,Biology ,Chromatin remodeling ,Cell Line ,Epigenesis, Genetic ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,0302 clinical medicine ,Humans ,WDR5 ,Epigenetics ,Induced pluripotent stem cell ,Molecular Biology ,Human induced pluripotent stem cells (hiPSCs) ,Neurons ,Genetics ,DNA methylation ,Intracellular Signaling Peptides and Proteins ,dNaM ,Huntington's disease ,Cell Differentiation ,Histone-Lysine N-Methyltransferase ,Cell Biology ,Chromatin Assembly and Disassembly ,Chromatin ,Cell biology ,Huntington Disease ,030104 developmental biology ,030217 neurology & neurosurgery - Abstract
DNA methylation (DNAm) changes are of increasing relevance to neurodegenerative disorders, including Huntington's disease (HD). We performed genome-wide screening of possible DNAm changes occurring during striatal differentiation in human induced pluripotent stem cells derived from a HD patient (HD-hiPSCs) as cellular model. We identified 240 differentially methylated regions (DMRs) at promoters in fully differentiated HD-hiPSCs. Subsequently, we focused on the methylation differences in a subcluster of genes related to Jumonji Domain Containing 3 (JMJD3), a demethylase that epigenetically regulates neuronal differentiation and activates neuronal progenitor associated genes, which are indispensable for neuronal fate acquisition. Noticeably among these genes, WD repeat-containing protein 5 (WDR5) promoter was found hypermethylated in HD-hiPSCs, resulting in a significant down-modulation in its expression and of the encoded protein. A similar WDR5 expression decrease was seen in a small series of HD-hiPSC lines characterized by different CAG length. The decrease in WDR5 expression was particularly evident in HD-hiPSCs compared to hESCs and control-hiPSCs from healthy subjects. WDR5 is a core component of the MLL/SET1 chromatin remodeling complexes essential for H3K4me3, previously reported to play an important role in stem cells self-renewal and differentiation. These results suggest the existence of epigenetic mechanisms in HD and the identification of genes, which are able to modulate HD phenotype, is important both for biomarker discovery and therapeutic interventions.
- Published
- 2017
21. Tight expression regulation of senataxin, linked to motor neuron disease and ataxia, is required to avert cell-cycle block and nucleolus disassembly
- Author
-
Bryce L. Sopher, Craig L. Bennett, and Albert R. La Spada
- Subjects
0301 basic medicine ,Cell biology ,Ataxia ,ALS4 ,RNA polymerase II ,Biology ,Article ,Helicase ,03 medical and health sciences ,0302 clinical medicine ,Transcription (biology) ,Gene expression ,Genetics ,medicine ,lcsh:Social sciences (General) ,Senataxin ,lcsh:Science (General) ,Gene ,Regulation of gene expression ,Infectious disease ,Multidisciplinary ,DNA replication ,C130 Cell Biology ,Nucleolus ,Cell cycle ,Gene regulation ,C431 Medical Genetics ,030104 developmental biology ,Fibrillarin ,Mutation ,biology.protein ,lcsh:H1-99 ,medicine.symptom ,030217 neurology & neurosurgery ,Neuroscience ,lcsh:Q1-390 - Abstract
The Senataxin (SETX) protein exhibits strong sequence conservation with the helicase domain of the yeast protein Sen1p, and recessive SETX mutations cause a severe ataxia, known as Ataxia with Oculomotor Apraxia type 2, while dominant SETX mutations cause Amyotrophic Lateral Sclerosis type 4. SETX is a very low abundance protein, and its expression is tightly regulated, such that large increases in mRNA levels fail to significantly increase protein levels. Despite this, transient transfection in cell culture can boost SETX protein levels on an individual cell basis. Here we found that over-expression of normal SETX, but not enzymatically-dead SETX, is associated with S-phase cell-cycle arrest in HEK293A cells. As SETX interacts with the nuclear exosome to ensure degradation of incomplete RNA transcripts, and SETX localizes to sites of collision between the DNA replication machinery and the RNAP II complex, altered dosage or aberrant function of SETX may impede this process to promote S-phase cell-cycle arrest. Because neurons are enriched for long transcripts with additional antisense regulatory transcription, collisions of RNAP II complexes may occur in such post-mitotic cells, underscoring a role for SETX in maintaining neuron homeostasis., Cell biology; Genetics; Neuroscience; Infectious disease; Gene Expression; Gene Regulation; Mutation; Senataxin; helicase; Fibrillarin; ALS4; nucleolus; ataxia
- Published
- 2020
22. Autophagy gene haploinsufficiency drives chromosome instability, increases migration, and promotes early ovarian tumors
- Author
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Chandni Patel, Dwayne G. Stupack, Katherine K. Ortell, David D. Schlaepfer, Christian M. Jones, Isabelle Tancioni, Ralph Tanios, Olivier Harismendy, Jaidev Bapat, Mina Haghighiabyaneh, Albert R. La Spada, Maria Ramos-Zapatero, John W. DeStefano, Joe R. Delaney, Joshua Axelrod, and Kwiatkowski, David J
- Subjects
Cancer Research ,endocrine system diseases ,Epidemiology ,Carcinogenesis ,Gene Identification and Analysis ,Genetic Networks ,Haploinsufficiency ,Tumor initiation ,QH426-470 ,medicine.disease_cause ,Suppressor Genes ,Mice ,0302 clinical medicine ,Cell Movement ,Chromosome instability ,Medicine and Health Sciences ,2.1 Biological and endogenous factors ,Aetiology ,Genetics (clinical) ,Cancer ,Ovarian Neoplasms ,0303 health sciences ,Mammalian Genomics ,Tumor ,Cell Death ,Chromosome Biology ,Cancer Risk Factors ,Animal Models ,Genomics ,BECN1 ,Ovarian Cancer ,3. Good health ,Chromosome 17 (human) ,Oncology ,Experimental Organism Systems ,Cell Processes ,Metabolome ,Female ,Beclin-1 ,Microtubule-Associated Proteins ,MAP1LC3B ,Network Analysis ,Research Article ,Computer and Information Sciences ,Chromosome Structure and Function ,Autophagic Cell Death ,Tumor Suppressor Genes ,Genetic Causes of Cancer ,Mouse Models ,Biology ,Research and Analysis Methods ,Chromosomes ,Cell Line ,03 medical and health sciences ,Model Organisms ,Rare Diseases ,Gene Types ,Cell Line, Tumor ,Chromosomal Instability ,Breast Cancer ,medicine ,Genetics ,Animals ,Molecular Biology ,Ecology, Evolution, Behavior and Systematics ,030304 developmental biology ,Human Genome ,Biology and Life Sciences ,Cancers and Neoplasms ,Cell Biology ,medicine.disease ,Animal Genomics ,Medical Risk Factors ,Animal Studies ,Cancer research ,Ovarian cancer ,Gynecological Tumors ,030217 neurology & neurosurgery ,Developmental Biology - Abstract
Autophagy, particularly with BECN1, has paradoxically been highlighted as tumor promoting in Ras-driven cancers, but potentially tumor suppressing in breast and ovarian cancers. However, studying the specific role of BECN1 at the genetic level is complicated due to its genomic proximity to BRCA1 on both human (chromosome 17) and murine (chromosome 11) genomes. In human breast and ovarian cancers, the monoallelic deletion of these genes is often co-occurring. To investigate the potential tumor suppressor roles of two of the most commonly deleted autophagy genes in ovarian cancer, BECN1 and MAP1LC3B were knocked-down in atypical (BECN1+/+ and MAP1LC3B+/+) ovarian cancer cells. Ultra-performance liquid chromatography mass-spectrometry metabolomics revealed reduced levels of acetyl-CoA which corresponded with elevated levels of glycerophospholipids and sphingolipids. Migration rates of ovarian cancer cells were increased upon autophagy gene knockdown. Genomic instability was increased, resulting in copy-number alteration patterns which mimicked high grade serous ovarian cancer. We further investigated the causal role of Becn1 haploinsufficiency for oncogenesis in a MISIIR SV40 large T antigen driven spontaneous ovarian cancer mouse model. Tumors were evident earlier among the Becn1+/- mice, and this correlated with an increase in copy-number alterations per chromosome in the Becn1+/- tumors. The results support monoallelic loss of BECN1 as permissive for tumor initiation and potentiating for genomic instability in ovarian cancer., Author summary Life requires an excellent trash and recycling system. One system mammalian cells rely upon is called autophagy. Autophagy clears cells of larger forms of debris and is critical for normal cell function. We previously found that ovarian cancer cells are unable to execute normal cellular recycling during periods of stress, due to losses in core autophagy genes. Since autophagy has previously been implicated as a cancer cell survival factor, we directly investigated the impact of autophagy gene loss in ovarian cancer models. We discovered a reduction in autophagy proteins disabled normal genome quality control during cell division, leading to genomic instability. We document here for the first time whether reducing an autophagy gene in mice influences ovarian tumor formation. We found earlier ovarian tumors in autophagy deficient mice compared with control mice. We conclude that serous ovarian carcinomas, which rank among the most genetically altered cancers, gain their hallmark genomic instability in part by losing autophagy genes.
- Published
- 2020
23. Converging pathways in neurodegeneration, from genetics to mechanisms
- Author
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Li Gan, Mark R. Cookson, Leonard Petrucelli, and Albert R. La Spada
- Subjects
0301 basic medicine ,Genetics ,Innate immune system ,General Neuroscience ,Neurodegeneration ,Cellular pathways ,Neurodegenerative Diseases ,Biology ,medicine.disease ,Article ,Human genetics ,03 medical and health sciences ,030104 developmental biology ,Stress granule ,Rare mutations ,medicine ,Animals ,Humans ,Genetic Predisposition to Disease ,Mitochondrial homeostasis ,Allele ,Neuroscience - Abstract
Neurodegenerative diseases cause progressive loss of cognitive and/or motor function and pose major challenges for societies with rapidly aging populations. Human genetics studies have shown that disease-causing rare mutations and risk-associated common alleles overlap in different neurodegenerative disorders. Here we review the intricate genotype-phenotype relationships and common cellular pathways emerging from recent genetic and mechanistic studies. Shared pathological mechanisms include defective protein quality-control and degradation pathways, dysfunctional mitochondrial homeostasis, stress granules, and maladaptive innate immune responses. Research efforts have started to bear fruit, as shown by recent treatment successes and an encouraging therapeutic outlook.
- Published
- 2018
24. Generation of Human-Induced Pluripotent Stem Cells from Wolfram Syndrome Type 2 Patients Bearing the c.103 + 1G>A CISD2 Mutation for Disease Modeling
- Author
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Pasquale De Blasio, Ida Biunno, Maurizio Rondinelli, Aikaterini Ntai, Alberto La Spada, and Stefano Genovese
- Subjects
Male ,0301 basic medicine ,Mitochondrial Diseases ,Wolfram syndrome ,Hearing Loss, Sensorineural ,Induced Pluripotent Stem Cells ,030105 genetics & heredity ,Biology ,medicine.disease_cause ,03 medical and health sciences ,Exon ,Atrophy ,medicine ,Humans ,Induced pluripotent stem cell ,Gene ,Cells, Cultured ,Cell Proliferation ,Family Health ,Genetics ,Mutation ,Siblings ,Intron ,Membrane Proteins ,Aging, Premature ,Cell Biology ,Hematology ,Fibroblasts ,medicine.disease ,Introns ,Optic Atrophy ,030104 developmental biology ,RNA splicing ,Female ,RNA Splice Sites ,Developmental Biology - Abstract
Wolfram syndrome (WFS) is a rare autosomal premature aging syndrome that shows signs of diabetes mellitus, optic atrophy, and deafness in addition to central nervous system and endocrine complications. The frequent form of WFS type 1 (WFS1) harbors causative mutations in the WFS1 gene, whereas the rare form or WFS type 2 (WFS2) involves CISD2. Mutations in these two genes are recognized by a subset of variable clinical symptoms and a set of overlapping features. In this study, we report on the generation of stable human-induced pluripotent stem cells (hiPSCs) derived from primary fibroblasts of a previously reported Italian family with CISD2 mutation (c.103 + 1G>A), occurring in the consensus intron 1 splicing site in two sisters, deleting the first exon of the transcript. The generated hiPSCs provide a cell model system to study the mutation's role in the multisystemic clinical disorders previously described and test eventual drug effects on the specific and associated clinical phenotype.
- Published
- 2018
25. CTCF cis-regulates trinucleotide repeat instability in an epigenetic manner: a novel basis for mutational hot spot determination.
- Author
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Randell T Libby, Katharine A Hagerman, Victor V Pineda, Rachel Lau, Diane H Cho, Sandy L Baccam, Michelle M Axford, John D Cleary, James M Moore, Bryce L Sopher, Stephen J Tapscott, Galina N Filippova, Christopher E Pearson, and Albert R La Spada
- Subjects
Genetics ,QH426-470 - Abstract
At least 25 inherited disorders in humans result from microsatellite repeat expansion. Dramatic variation in repeat instability occurs at different disease loci and between different tissues; however, cis-elements and trans-factors regulating the instability process remain undefined. Genomic fragments from the human spinocerebellar ataxia type 7 (SCA7) locus, containing a highly unstable CAG tract, were previously introduced into mice to localize cis-acting "instability elements," and revealed that genomic context is required for repeat instability. The critical instability-inducing region contained binding sites for CTCF -- a regulatory factor implicated in genomic imprinting, chromatin remodeling, and DNA conformation change. To evaluate the role of CTCF in repeat instability, we derived transgenic mice carrying SCA7 genomic fragments with CTCF binding-site mutations. We found that CTCF binding-site mutation promotes triplet repeat instability both in the germ line and in somatic tissues, and that CpG methylation of CTCF binding sites can further destabilize triplet repeat expansions. As CTCF binding sites are associated with a number of highly unstable repeat loci, our findings suggest a novel basis for demarcation and regulation of mutational hot spots and implicate CTCF in the modulation of genetic repeat instability.
- Published
- 2008
- Full Text
- View/download PDF
26. The replicative lifespan‐extending deletion of SGF73 results in altered ribosomal gene expression in yeast
- Author
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Amanda G. Mason, Renee M. Garza, Lorraine Pillus, Mark A. McCormick, Bhumil Patel, Brian K. Kennedy, and Albert R. La Spada
- Subjects
0301 basic medicine ,Aging ,Mutant ,Sequence Homology ,yeast ,Medical and Health Sciences ,0302 clinical medicine ,Sgf73 ,Gene Expression Regulation, Fungal ,Gene expression ,genome‐wide occupancy ,Promoter Regions, Genetic ,Histone Acetyltransferases ,Genetics ,Acetylation ,Biological Sciences ,Amino Acid ,Fungal ,genome-wide occupancy ,Spinocerebellar ataxia ,Original Article ,Cell Division ,Protein Binding ,Signal Transduction ,Ribosomal Proteins ,Saccharomyces cerevisiae Proteins ,Saccharomyces cerevisiae ,Biology ,Promoter Regions ,03 medical and health sciences ,longevity gene ,Genetic ,Ribosomal protein ,mental disorders ,medicine ,Humans ,Spinocerebellar Ataxias ,Neurodegeneration ,replicative lifespan ,Gene ,Ataxin-7 ,Binding Sites ,Microbial Viability ,Base Sequence ,Sequence Homology, Amino Acid ,Promoter ,Molecular Sequence Annotation ,Cell Biology ,Original Articles ,Ribosomal RNA ,medicine.disease ,030104 developmental biology ,Gene Expression Regulation ,Trans-Activators ,Trinucleotide repeat expansion ,030217 neurology & neurosurgery ,Gene Deletion ,Developmental Biology - Abstract
Summary Sgf73, a core component of SAGA, is the yeast orthologue of ataxin‐7, which undergoes CAG–polyglutamine repeat expansion leading to the human neurodegenerative disease spinocerebellar ataxia type 7 (SCA7). Deletion of SGF73 dramatically extends replicative lifespan (RLS) in yeast. To further define the basis for Sgf73‐mediated RLS extension, we performed ChIP‐Seq, identified 388 unique genomic regions occupied by Sgf73, and noted enrichment in promoters of ribosomal protein (RP)‐encoding genes. Of 388 Sgf73 binding sites, 33 correspond to 5′ regions of genes implicated in RLS extension, including 20 genes encoding RPs. Furthermore, half of Sgf73‐occupied, RLS‐linked RP genes displayed significantly reduced expression in sgf73Δ mutants, and double null strains lacking SGF73 and a Sgf73‐regulated, RLS‐linked RP gene exhibited no further increase in replicative lifespan. We also found that sgf73Δ mutants display altered acetylation of Ifh1, an important regulator of RP gene transcription. These findings implicate altered ribosomal protein expression in sgf73Δ yeast RLS and highlight altered acetylation as a pathway of relevance for SCA7 neurodegeneration.
- Published
- 2017
27. Metabolic and Organelle Morphology Defects in Mice and Human Patients Define Spinocerebellar Ataxia Type 7 as a Mitochondrial Disease
- Author
-
Pawel M. Switonski, Ronald M. Evans, Fanny Mochel, Weiwei Fan, Christopher E. Wall, Chenchen Niu, Chizuru Kinoshita, Farid Ichou, Jacqueline M. Ward, Alysson R. Muotri, Albert R. La Spada, Colleen A. Stoyas, Isaac Adanyeguh, Alexandra Durr, Richard S. Morrison, Bryce L. Sopher, Brett Collins, University of California [San Diego] (UC San Diego), University of California, Duke University [Durham], Institute of Bioorganic Chemistry [Poznań], Polska Akademia Nauk = Polish Academy of Sciences (PAN), Polish Academy of Sciences (PAN), Unité de Recherche sur les Maladies Cardiovasculaires, du Métabolisme et de la Nutrition = Institute of cardiometabolism and nutrition (ICAN), Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Institut National de la Santé et de la Recherche Médicale (INSERM)-CHU Pitié-Salpêtrière [AP-HP], Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), Institut du Cerveau et de la Moëlle Epinière = Brain and Spine Institute (ICM), Institut National de la Santé et de la Recherche Médicale (INSERM)-CHU Pitié-Salpêtrière [AP-HP], Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), University of Washington [Seattle], Service de Génétique Cytogénétique et Embryologie [CHU Pitié-Salpêtrière], CHU Pitié-Salpêtrière [AP-HP], and Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)
- Subjects
0301 basic medicine ,Blood Glucose ,Mitochondrial Diseases ,[SDV.NEU.NB]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC]/Neurobiology ,Purkinje cell ,Medical Physiology ,Nicotinamide adenine dinucleotide ,Mitochondrion ,Neurodegenerative ,chemistry.chemical_compound ,Purkinje Cells ,Mice ,0302 clinical medicine ,spinocerebellar ataxia ,Neural Stem Cells ,oxidative metabolism ,2.1 Biological and endogenous factors ,Aetiology ,lcsh:QH301-705.5 ,Kynurenine ,Tryptophan ,3. Good health ,Cell biology ,Mitochondria ,mitochondria ,medicine.anatomical_structure ,Phenotype ,Adipose Tissue ,Neurological ,Spinocerebellar ataxia ,Stem cell ,trinucleotide repeat ,Ataxin 7 ,induced pluripotent stem cells ,Mitochondrial disease ,mouse model ,Biology ,Article ,General Biochemistry, Genetics and Molecular Biology ,03 medical and health sciences ,Rare Diseases ,medicine ,Genetics ,Animals ,Humans ,Spinocerebellar Ataxias ,Metabolomics ,nicotinamide adenine dinucleotide ,Organelles ,Ataxin-7 ,Neurosciences ,Reproducibility of Results ,ataxin-7 ,medicine.disease ,Stem Cell Research ,NAD ,Brain Disorders ,030104 developmental biology ,lcsh:Biology (General) ,chemistry ,biology.protein ,NAD+ kinase ,Biochemistry and Cell Biology ,Peptides ,Trinucleotide Repeat Expansion ,Energy Metabolism ,polyglutamine ,030217 neurology & neurosurgery - Abstract
SUMMARY Spinocerebellar ataxia type 7 (SCA7) is a retinal-cerebellar degenerative disorder caused by CAG-polyglutamine (polyQ) repeat expansions in the ataxin-7 gene. As many SCA7 clinical phenotypes occur in mitochondrial disorders, and magnetic resonance spectroscopy of patients revealed altered energy metabolism, we considered a role for mitochondrial dysfunction. Studies of SCA7 mice uncovered marked impairments in oxygen consumption and respiratory exchange. When we examined cerebellar Purkinje cells in mice, we observed mitochondrial network abnormalities, with enlarged mitochondria upon ultrastructural analysis. We developed stem cell models from patients and created stem cell knockout rescue systems, documenting mitochondrial morphology defects, impaired oxidative metabolism, and reduced expression of nicotinamide adenine dinucleotide (NAD+) production enzymes in SCA7 models. We observed NAD+ reductions in mitochondria of SCA7 patient NPCs using ratiometric fluorescent sensors and documented alterations in tryptophan-kynurenine metabolism in patients. Our results indicate that mitochondrial dysfunction, stemming from decreased NAD+, is a defining feature of SCA7., Graphical Abstract, In Brief Ward et al. document altered metabolism and mitochondrial dysfunction in SCA7 patients, mice, and human stem cell-derived neurons. They link these abnormalities to reduced nicotinamide adenine dinucleotide in specific subcellular compartments. Given the role of mitochondrial impairment in neurodegeneration, their results have therapeutic implications for SCA7 and related neurological disorders.
- Published
- 2019
28. Astroglial-targeted expression of the fragile X CGG repeat premutation in mice yields RAN translation, motor deficits and possible evidence for cell-to-cell propagation of FXTAS pathology
- Author
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Kyoungmi Kim, Michael R. Hunsaker, Lies Anne Severijnen, Saif N Haify, Rob Willemsen, Albert R. La Spada, H. Jürgen Wenzel, Paul J. Hagerman, Christopher Raske, Bryce L. Sopher, Robert F. Berman, Karl D Murray, Renate K. Hukema, Jared J. Schwartzer, and Clinical Genetics
- Subjects
0301 basic medicine ,Male ,Pathology ,Gene Expression ,Cell Communication ,Neurodegenerative ,Inbred C57BL ,Transgenic ,lcsh:RC346-429 ,Fragile X Mental Retardation Protein ,Mice ,0302 clinical medicine ,Tremor ,Non-cell-autonomous ,Neocortex ,biology ,Neurodegeneration ,Fragile X premutation ,Motor Skills Disorders ,medicine.anatomical_structure ,Neurological ,FMRpolyG ,medicine.symptom ,Astrocyte ,medicine.medical_specialty ,Ataxia ,Intellectual and Developmental Disabilities (IDD) ,Clinical Sciences ,Mice, Transgenic ,Neuropathology ,Pathology and Forensic Medicine ,Mouse model ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,Rare Diseases ,RAN translation ,Glia ,Genetics ,medicine ,Animals ,lcsh:Neurology. Diseases of the nervous system ,Electron microscopy of inclusions ,Base Sequence ,Research ,Neurosciences ,medicine.disease ,FMR1 ,Brain Disorders ,Mice, Inbred C57BL ,030104 developmental biology ,nervous system ,Astrocytes ,Fragile X Syndrome ,biology.protein ,Biochemistry and Cell Biology ,Neurology (clinical) ,FXTAS ,NeuN ,Trinucleotide repeat expansion ,Trinucleotide Repeat Expansion ,030217 neurology & neurosurgery - Abstract
The fragile X premutation is a CGG trinucleotide repeat expansion between 55 and 200 repeats in the 5′-untranslated region of the fragile X mental retardation 1 (FMR1) gene. Human carriers of the premutation allele are at risk of developing the late-onset neurodegenerative disorder, fragile X-associated tremor/ataxia syndrome (FXTAS). Characteristic neuropathology associated with FXTAS includes intranuclear inclusions in neurons and astroglia. Previous studies recapitulated these histopathological features in neurons in a knock-in mouse model, but without significant astroglial pathology. To determine the role of astroglia in FXTAS, we generated a transgenic mouse line (Gfa2-CGG99-eGFP) that selectively expresses a 99-CGG repeat expansion linked to an enhanced green fluorescent protein (eGFP) reporter in astroglia throughout the brain, including cerebellar Bergmann glia. Behaviorally these mice displayed impaired motor performance on the ladder-rung test, but paradoxically better performance on the rotarod. Immunocytochemical analysis revealed that CGG99-eGFP co-localized with GFAP and S-100ß, but not with NeuN, Iba1, or MBP, indicating that CGG99-eGFP expression is specific to astroglia. Ubiquitin-positive intranuclear inclusions were found in eGFP-expressing glia throughout the brain. In addition, intracytoplasmic ubiquitin-positive inclusions were found outside the nucleus in distal astrocyte processes. Intriguingly, intranuclear inclusions, in the absence of eGFP mRNA and eGFP fluorescence, were present in neurons of the hypothalamus and neocortex. Furthermore, intranuclear inclusions in both neurons and astrocytes displayed immunofluorescent labeling for the polyglycine peptide FMRpolyG, implicating FMRpolyG in the pathology found in Gfa2-CGG99 mice. Considered together, these results show that Gfa2-CGG99 expression in mice is sufficient to induce key features of FXTAS pathology, including formation of intranuclear inclusions, translation of FMRpolyG, and deficits in motor function. Electronic supplementary material The online version of this article (10.1186/s40478-019-0677-7) contains supplementary material, which is available to authorized users.
- Published
- 2019
29. Genetic epidemiology of autosomal recessive hypercholesterolemia in Sicily: Identification by next-generation sequencing of a new kindred
- Author
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Roberto Monastero, Gabriella Misiano, Maurizio Averna, Davide Noto, V. Ingrassia, Antonina Pipitone, Vincenza Valenti, Angelo B. Cefalù, Rossella Spina, C. Scrimali, Carlo M. Barbagallo, Antonina Giammanco, Maria P. La Spada, Roberta Baschi, Spina, R., Noto, D., Barbagallo, C., Monastero, R., Ingrassia, V., Valenti, V., Baschi, R., Pipitone, A., Giammanco, A., La Spada, M., Misiano, G., Scrimali, C., Cefalu', A., and Averna, M.
- Subjects
0301 basic medicine ,Male ,Settore MED/09 - Medicina Interna ,Endocrinology, Diabetes and Metabolism ,Familial hypercholesterolemia ,030204 cardiovascular system & hematology ,0302 clinical medicine ,Child ,N-Glycosyl Hydrolases ,Sicily ,Genetics ,Aged, 80 and over ,education.field_of_study ,Nutrition and Dietetics ,Allele frequency ,Homozygote ,High-Throughput Nucleotide Sequencing ,Autosomal recessive hypercholesterolemia ,Middle Aged ,Autosomal Recessive Hypercholesterolemia ,Settore MED/26 - Neurologia ,Female ,Cardiology and Cardiovascular Medicine ,Adult ,Adolescent ,Genotype ,Population ,Hypercholesterolemia ,Biology ,DNA sequencing ,03 medical and health sciences ,Young Adult ,ARH1 ,Internal Medicine ,medicine ,Humans ,Allele ,education ,Genotyping ,Alleles ,Adaptor Proteins, Signal Transducing ,Aged ,Heterozygous carrier ,Sequence Analysis, DNA ,medicine.disease ,NGS-based gene panel ,030104 developmental biology ,Genetic epidemiology ,Receptors, LDL - Abstract
Background Autosomal recessive hypercholesterolemia (ARH) is a rare inherited lipid disorder. In Sardinia, differently from other world regions, the mutated allele frequency is high. It is caused by mutations in the low-density lipoprotein receptor adaptor protein 1 gene. Fourteen different mutations have been reported so far; in Sardinia, 2 alleles (ARH1 and ARH2) explain most of the cases. Four ARH patients, all carriers of the ARH1 mutation, have been identified in mainland Italy and 2 in Sicily. Objective The objectives of the study were to improve the molecular diagnosis of familial hypercholesterolemia (FH) and to estimate the frequency of the ARH1 allele in 2 free-living Sicilian populations. Methods We sequenced by targeted next-generation sequencing 20 genes related to low-density lipoprotein metabolism in 50 hypercholesterolemic subjects. Subjects from 2 free-living populations from Northern (Ventimiglia Heart Study, 848 individuals) and Southern Sicily (Zabut Zabut Aging Project, 1717 individuals) were genotyped for ARH1 allele. Results We identified 1 homozygous carrier of the ARH1 mutation among the 50 hypercholesterolemic outpatients. Population-based genotyping of ARH1 in 2565 subjects allowed the identification of 1 heterozygous carrier. The overall estimated allele frequency of ARH1 in Sicily was 0.0002 (0.02%). Conclusions The identification of a new case of ARH in Sicily among 50 clinically diagnosed FH highlights the importance of next-generation sequencing analysis as tool to improve the FH diagnosis. Our results also indicate that ARH1 carrier status is present in ∼1:2500 of Sicilian inhabitants, confirming that ARH is extremely rare outside Sardinia.
- Published
- 2017
30. Respiratory Dysfunction in a Mouse Model of Spinocerebellar Ataxia 7
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Angela L McCall, Laura M Strickland, Amanda F Kahn, Justin S Dhindsa, Anna F Fusco, Logan A Pucci, Albert R. La Spada, Pawel M. Switonski, and Mai K. ElMallah
- Subjects
Pathology ,medicine.medical_specialty ,business.industry ,Respiratory dysfunction ,Genetics ,medicine ,Spinocerebellar ataxia ,medicine.disease ,business ,Molecular Biology ,Biochemistry ,Biotechnology - Published
- 2020
31. Overriding FUS autoregulation in mice triggers gain-of-toxic dysfunctions in RNA metabolism and autophagy-lysosome axis
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Kenneth Lim, Shuying Sun, Sandrine Da Cruz, Debbie Swing, Wan Yun Ho, Philippe A. Parone, Ngoc B. Bui, Jer Cherng Chang, Clotilde Lagier-Tourenne, Joo Seok Han, Albert R. La Spada, Hristelina Ilieva, Anh Bui, Melissa McAlonis-Downes, Katannya Kapeli, Don W. Cleveland, Seiya Tokunaga, Greg Tucker-Kellogg, Martin Marsala, Christopher Shaw, Oleksandr Platoshyn, Somasish Ghosh Dastidar, Tsemay M. Tse, Shuo-Chien Ling, Gene W. Yeo, Sheue Houy Tyan, Lino Tessarollo, and Anne P. Vetto
- Subjects
0301 basic medicine ,amyotrophic lateral sclerosis ,amyotrophic lateral sclerosis (ALS) ,Mouse ,Neurodegenerative ,Inbred C57BL ,Transcriptome ,neuroscience ,Mice ,0302 clinical medicine ,autophagy-lysosome ,homeostasis ,2.1 Biological and endogenous factors ,Homeostasis ,Aetiology ,Biology (General) ,General Neuroscience ,General Medicine ,Phenotype ,Cell biology ,medicine.anatomical_structure ,Neurological ,Medicine ,Research Article ,QH301-705.5 ,Science ,Biology ,General Biochemistry, Genetics and Molecular Biology ,03 medical and health sciences ,Rare Diseases ,Lysosome ,medicine ,Genetics ,Autophagy ,Animals ,Humans ,Gene ,frontotemporal degeneration ,mouse ,FUS ,RNA metabolism ,Messenger RNA ,General Immunology and Microbiology ,Gene Expression Profiling ,Amyotrophic Lateral Sclerosis ,Neurotoxicity ,Neurosciences ,RNA ,medicine.disease ,Brain Disorders ,Mice, Inbred C57BL ,030104 developmental biology ,Mutation ,Commentary ,RNA-Binding Protein FUS ,Mutant Proteins ,Biochemistry and Cell Biology ,ALS ,Lysosomes ,frontotemporal degeneration (FTD) ,030217 neurology & neurosurgery ,Neuroscience - Abstract
Coding or non-coding mutations in FUS (fused in sarcoma) cause amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). In addition to familial ALS, abnormal aggregates of FUS are present in a portion of FTD and other neurodegenerative diseases independent of their mutations. Broad expression within the central nervous system of either wild-type or two ALS-linked human FUS mutants produces progressive motor phenotypes accompanied by characteristic ALS-like pathology. FUS levels are autoregulated to maintain an optimal steady-state level. Increasing FUS expression by saturating its autoregulatory mechanism results in rapidly progressive neurological phenotypes and dose-dependent lethality. Genome-wide expression analysis reveals genetic mis-regulations distinct from those via FUS reduction. Among these are increased expression of lysosomal proteins, suggestive of disruption in protein homeostasis as a potential gain-of-toxicity mechanism. Indeed, increased expression of wild-type FUS or ALS-linked mutant forms of FUS inhibit macroautophagy/autophagy. Collectively, our results demonstrate that: (1) mice expressing FUS develop progressive motor deficits, (2) increased FUS expression by overriding its autoregulatory mechanism accelerates neurodegeneration, providing a basis for FUS involvement without mutation, and (3) disruption in both protein homeostasis and RNA processing contribute to FUS-mediated toxicity.
- Published
- 2018
32. The CAG–polyglutamine repeat diseases: a clinical, molecular, genetic, and pathophysiologic nosology
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Albert R. La Spada and Colleen A. Stoyas
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0301 basic medicine ,Nosology ,Genetics ,congenital, hereditary, and neonatal diseases and abnormalities ,Dentatorubral-pallidoluysian atrophy ,Cerebellar ataxia ,Disease ,Biology ,medicine.disease ,03 medical and health sciences ,Spinal and bulbar muscular atrophy ,030104 developmental biology ,0302 clinical medicine ,medicine ,Spinocerebellar ataxia ,medicine.symptom ,Trinucleotide repeat expansion ,Gene ,030217 neurology & neurosurgery - Abstract
Throughout the genome, unstable tandem nucleotide repeats can expand to cause a variety of neurologic disorders. Expansion of a CAG triplet repeat within a coding exon gives rise to an elongated polyglutamine (polyQ) tract in the resultant protein product, and accounts for a unique category of neurodegenerative disorders, known as the CAG-polyglutamine repeat diseases. The nine members of the CAG-polyglutamine disease family include spinal and bulbar muscular atrophy (SBMA), Huntington disease, dentatorubral pallidoluysian atrophy, and six spinocerebellar ataxias (SCA 1, 2, 3, 6, 7, and 17). All CAG-polyglutamine diseases are dominantly inherited, with the exception of SBMA, which is X-linked, and many CAG-polyglutamine diseases display anticipation, which is defined as increasing disease severity in successive generations of an affected kindred. Despite widespread expression of the different polyQ-expanded disease proteins throughout the body, each CAG-polyglutamine disease strikes a particular subset of neurons, although the mechanism for this cell-type selectivity remains poorly understood. While the different genes implicated in these disorders display amino acid homology only in the repeat tract domain, certain pathologic molecular processes have been implicated in almost all of the CAG-polyglutamine repeat diseases, including protein aggregation, proteolytic cleavage, transcription dysregulation, autophagy impairment, and mitochondrial dysfunction. Here we highlight the clinical and molecular genetic features of each distinct disorder, and then discuss common themes in CAG-polyglutamine disease pathogenesis, closing with emerging advances in therapy development.
- Published
- 2018
33. Huntington’s Disease and Other Polyglutamine Repeat Diseases
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Audrey S. Dickey and Albert R. La Spada
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Zinc finger ,Genetics ,congenital, hereditary, and neonatal diseases and abnormalities ,Spinal and bulbar muscular atrophy ,Atrophy ,Huntington's disease ,RNA interference ,Neurodegeneration ,medicine ,Spinocerebellar ataxia ,Biology ,medicine.disease ,Gene - Abstract
Polyglutamine diseases are inherited, fatal neurodegenerative disorders caused by genomic expansion of exonic cytosine–adenine–guanine (CAG) trinucleotide repeats. These diseases include Huntington’s disease, spinal and bulbar muscular atrophy, dentatorubral–pallidoluysian atrophy, and spinocerebellar ataxia types 1, 2, 3, 6, 7, and 17, each due to CAG expansion in a different gene. Common themes regarding mechanisms of neurodegeneration include protein aggregation, intracellular protein degradation systems, proteolytic processing, mitochondrial dysfunction, nuclear trafficking and subcellular localization, transcriptional dysregulation, and posttranslational modifications. Strategies for developing therapeutics for this class of neurodegenerative diseases include RNA interference, antisense oligonucleotides, zinc finger proteins, and genome editing.
- Published
- 2018
34. Therapy development in Huntington disease: From current strategies to emerging opportunities
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Audrey S. Dickey and Albert R. La Spada
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0301 basic medicine ,Huntingtin ,Tetrabenazine ,Vesicular monoamine transporter 2 ,Article ,03 medical and health sciences ,0302 clinical medicine ,Drug Development ,Genetics ,Medicine ,Animals ,Humans ,Cognitive decline ,Genetics (clinical) ,biology ,business.industry ,Neurodegeneration ,Disease Management ,Polyglutamine tract ,medicine.disease ,Mitochondria ,030104 developmental biology ,Huntington Disease ,Drug development ,biology.protein ,business ,Trinucleotide repeat expansion ,Energy Metabolism ,Trinucleotide Repeat Expansion ,Neuroscience ,030217 neurology & neurosurgery ,Biomarkers ,medicine.drug ,Signal Transduction - Abstract
Huntington disease (HD) is a progressive autosomal dominant neurodegenerative disorder in which patients typically present with uncontrolled involuntary movements and subsequent cognitive decline. In 1993, a CAG trinucleotide repeat expansion in the coding region of the huntingtin (HTT) gene was identified as the cause of this disorder. This extended CAG repeat results in production of HTT protein with an expanded polyglutamine tract, leading to pathogenic HTT protein conformers that are resistant to protein turnover, culminating in cellular toxicity and neurodegeneration. Research into the mechanistic basis of HD has highlighted a role for bioenergetics abnormalities stemming from mitochondrial dysfunction, and for synaptic defects, including impaired neurotransmission and excitotoxicity. Interference with transcription regulation may underlie the mitochondrial dysfunction. Current therapies for HD are directed at treating symptoms, as there are no disease-modifying therapies. Commonly prescribed drugs for involuntary movement control include tetrabenazine, a potent and selective inhibitor of vesicular monoamine transporter 2 that depletes synaptic monoamines, and olanzapine, an atypical neuroleptic that blocks the dopamine D2 receptor. Various drugs are used to treat non-motor features. The HD therapeutic pipeline is robust, as numerous efforts are underway to identify disease-modifying treatments, with some small compounds and biological agents moving into clinical trials. Especially encouraging are dosage reduction strategies, including antisense oligonucleotides, and molecules directed at transcription dysregulation. Given the depth and breadth of current HD drug development efforts, there is reason to believe that disease-modifying therapies for HD will emerge, and this achievement will have profound implications for the entire neurotherapeutics field.
- Published
- 2017
35. Muscle Expression of Mutant Androgen Receptor Accounts for Systemic and Motor Neuron Disease Phenotypes in Spinal and Bulbar Muscular Atrophy
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Taiji Tsunemi, Don W. Cleveland, Ling T. Guo, Shuo-Chien Ling, Edith Lopez, G. Diane Shelton, Linda Ly, Seiya Tokunaga, Bryce L. Sopher, Gene Hung, C. Frank Bennett, Constanza J. Cortes, and Albert R. La Spada
- Subjects
Male ,Pathology ,Neurodegenerative ,Transgenic ,Androgen ,Mice ,0302 clinical medicine ,Receptors ,2.1 Biological and endogenous factors ,Psychology ,Aetiology ,Regulation of gene expression ,Motor Neurons ,0303 health sciences ,Movement Disorders ,General Neuroscience ,Age Factors ,Brain ,Skeletal ,Phenotype ,Muscular Disorders, Atrophic ,3. Good health ,medicine.anatomical_structure ,Receptors, Androgen ,Neurological ,Disease Progression ,Muscle ,Cognitive Sciences ,medicine.symptom ,Biotechnology ,medicine.medical_specialty ,Transgene ,Neuroscience(all) ,Mice, Transgenic ,Biology ,Article ,03 medical and health sciences ,Rare Diseases ,medicine ,Genetics ,Animals ,Humans ,Muscle Strength ,Muscle, Skeletal ,Actin ,030304 developmental biology ,Atrophic ,Neurology & Neurosurgery ,Animal ,Body Weight ,Neurosciences ,Muscle weakness ,Motor neuron ,medicine.disease ,Actins ,Brain Disorders ,Androgen receptor ,Disease Models, Animal ,Spinal and bulbar muscular atrophy ,Muscular Disorders ,Orphan Drug ,Gene Expression Regulation ,Musculoskeletal ,Disease Models ,Peptides ,Neuroscience ,030217 neurology & neurosurgery - Abstract
SummaryX-linked spinal and bulbar muscular atrophy (SBMA) is characterized by adult-onset muscle weakness and lower motor neuron degeneration. SBMA is caused by CAG-polyglutamine (polyQ) repeat expansions in the androgen receptor (AR) gene. Pathological findings include motor neuron loss, with polyQ-AR accumulation in intranuclear inclusions. SBMA patients exhibit myopathic features, suggesting a role for muscle in disease pathogenesis. To determine the contribution of muscle, we developed a BAC mouse model featuring a floxed first exon to permit cell-type-specific excision of human AR121Q. BAC fxAR121 mice develop systemic and neuromuscular phenotypes, including shortened survival. After validating termination of AR121 expression and full rescue with ubiquitous Cre, we crossed BAC fxAR121 mice with Human Skeletal Actin-Cre mice. Muscle-specific excision prevented weight loss, motor phenotypes, muscle pathology, and motor neuronopathy and dramatically extended survival. Our results reveal a crucial role for muscle expression of polyQ-AR in SBMA and suggest muscle-directed therapies as effective treatments.
- Published
- 2014
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36. Reduction of mutant ataxin-7 expression restores motor function and prevents cerebellar synaptic reorganization in a conditional mouse model of SCA7
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Vincent A. Damian, Sarah M. Waldherr, Travis D. Baughn, Bryce L. Sopher, Stephanie A. Furrer, Gwenn A. Garden, Kien Thiet Nguyen, Mathini S. Mohanachandran, and Albert R. La Spada
- Subjects
Cerebellum ,Ataxia ,Ataxin 7 ,Transgene ,Mice, Transgenic ,Nerve Tissue Proteins ,Mice ,Purkinje Cells ,Genetics ,medicine ,Animals ,Humans ,Spinocerebellar Ataxias ,Molecular Biology ,Genetics (clinical) ,Ataxin-7 ,Regulation of gene expression ,biology ,Neurodegeneration ,Articles ,General Medicine ,medicine.disease ,Cell biology ,Disease Models, Animal ,medicine.anatomical_structure ,Gene Expression Regulation ,Mutation ,Spinocerebellar ataxia ,biology.protein ,medicine.symptom ,Peptides ,Trinucleotide Repeat Expansion ,Trinucleotide repeat expansion ,Locomotion - Abstract
Spinocerebellar ataxia type 7 (SCA7) is a dominantly inherited neurodegenerative disorder caused by a CAG - polyglutamine (polyQ) repeat expansion in the ataxin-7 gene. In polyQ disorders, synaptic dysfunction and neurodegeneration may develop prior to symptom onset. However, conditional expression studies of polyQ disease models demonstrate that suppression of gene expression can yield complete reversal of established behavioral abnormalities. To determine if SCA7 neurological and neurodegenerative phenotypes are reversible, we crossed PrP-floxed-SCA7-92Q BAC transgenic mice with a tamoxifen-inducible Cre recombinase transgenic line, CAGGS-Cre-ER™. PrP-floxed-SCA7-92Q BAC;CAGGS-Cre-ER™ bigenic mice were treated with a single dose of tamoxifen 1 month after the onset of detectable ataxia, which resulted in ~50% reduction of polyQ-ataxin-7 expression. Tamoxifen treatment halted or reversed SCA7 motor symptoms, reduced ataxin-7 aggregation in Purkinje cells (PCs), and prevented loss of climbing fiber (CF)-PC synapses in comparison to vehicle-treated bigenic animals and tamoxifen-treated PrP-floxed-SCA7-92Q BAC single transgenic mice. Despite this phenotype rescue, reduced ataxin-7 expression did not result in full recovery of cerebellar molecular layer thickness or prevent Bergmann glia degeneration. These results demonstrate that suppression of mutant gene expression by only 50% in a polyQ disease model can have a significant impact on disease phenotypes, even when initiated after the onset of detectable behavioral deficits. The findings reported here are consistent with the emerging view that therapies aimed at reducing neurotoxic gene expression hold the potential to halt or reverse disease progression in afflicted patients, even after the onset of neurological disability.
- Published
- 2012
37. Complete genome sequence of 'Halanaeroarchaeum sulfurireducens' M27-SA2, a sulfur-reducing and acetate-oxidizing haloarchaeon from the deep-sea hypersaline anoxic lake Medee
- Author
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Michail M. Yakimov, Gina La Spada, Erika Arcadi, Violetta La Cono, Stepan V. Toshchakov, Enzo Messina, Francesco Smedile, Anna Lopatina, Dimitry Y. Sorokin, and Ilya V. Kublanov
- Subjects
0301 basic medicine ,Genetics ,Whole genome sequencing ,Sulfur reduction ,Strictly anaerobic ,Hypersaline lake ,Anoxic habitats ,Biology ,Genome ,Anoxic waters ,Halophile ,03 medical and health sciences ,030104 developmental biology ,13. Climate action ,Extremely halophilic archaea ,Extreme environment ,Energy source ,Extended Genome Report ,Prophage - Abstract
Strain M27-SA2 was isolated from the deep-sea salt-saturated anoxic lake Medee, which represents one of the most hostile extreme environments on our planet. On the basis of physiological studies and phylogenetic positioning this extremely halophilic euryarchaeon belongs to a novel genus ‘Halanaeroarchaeum’ within the family Halobacteriaceae. All members of this genus cultivated so far are strict anaerobes using acetate as the sole carbon and energy source and elemental sulfur as electron acceptor. Here we report the complete genome sequence of the strain M27-SA2 which is composed of a 2,129,244-bp chromosome and a 124,256-bp plasmid. This is the second complete genome sequence within the genus Halanaeroarchaeum. We demonstrate that genome of ‘Halanaeroarchaeum sulfurireducens’ M27-SA2 harbors complete metabolic pathways for acetate and sulfur catabolism and for de novo biosynthesis of 19 amino acids. The genomic analysis also reveals that ‘Halanaeroarchaeum sulfurireducens’ M27-SA2 harbors two prophage loci and one CRISPR locus, highly similar to that of Kulunda Steppe (Altai, Russia) isolate ‘H. sulfurireducens’ HSR2T. The discovery of sulfur-respiring acetate-utilizing haloarchaeon in deep-sea hypersaline anoxic lakes has certain significance for understanding the biogeochemical functioning of these harsh ecosystems, which are incompatible with life for common organisms. Moreover, isolations of Halanaeroarchaeum members from geographically distant salt-saturated sites of different origin suggest a high degree of evolutionary success in their adaptation to this type of extreme biotopes around the world.
- Published
- 2016
38. Ataxin-7 associates with microtubules and stabilizes the cytoskeletal network
- Author
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Toshikazu Sasabe, Yoko Nakamura, Hikaru Ito, Hitoshi Okazawa, Albert R. La Spada, Kazuhiko Tagawa, Hiroki Shiwaku, and Tsutomu Oka
- Subjects
Cytoplasm ,Ataxin 7 ,Mitosis ,Nerve Tissue Proteins ,Biology ,Transfection ,Microtubules ,Gene product ,chemistry.chemical_compound ,Tubulin ,Microtubule ,Genetics ,medicine ,Humans ,Protein Interaction Domains and Motifs ,Cytoskeleton ,Molecular Biology ,Genetics (clinical) ,Ataxin-7 ,Cell Nucleus ,Cell Cycle ,Articles ,General Medicine ,medicine.disease ,Cell biology ,Nocodazole ,chemistry ,Spinocerebellar ataxia ,biology.protein ,RNA Interference ,HeLa Cells - Abstract
The spinocerebellar ataxia type 7 (SCA7) gene product, Ataxin-7 (ATXN7), localizes to the nucleus and has been shown to function as a component of the TATA-binding protein-free TAF-containing-SPT3-TAF9-GCN5-acetyltransferase transcription complex, although cytoplasmic localization of ATXN7 in affected neurons of human SCA7 patients has also been detected. Here, we define a physiological function for cytoplasmic ATXN7. Live imaging reveals that the intracellular distribution of ATXN7 dynamically changes and that ATXN7 distribution frequently shifts from the nucleus to the cytoplasm. Immunocytochemistry and immunoprecipitation demonstrate that cytoplasmic ATXN7 associates with microtubules (MTs), and expression of ATXN7 stabilizes MTs against nocodazole treatment, while ATXN7 knockdown enhances MT degradation. Interestingly, normal and mutant ATXN7 similarly associate with and equally stabilize MTs. Taken together, these findings provide a novel physiological function of ATXN7 in the regulation of cytoskeletal dynamics, and suggest that abnormal cytoskeletal regulation may contribute to SCA7 disease pathology.
- Published
- 2011
39. Sporadic ALS has compartment-specific aberrant exon splicing and altered cell–matrix adhesion biology
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Randell T. Libby, Ryan T. Libby, Albert R. La Spada, Jae Mun ‘Hugo’ Kim, Michael Baughn, Stuart J Rabin, Yuxin Fan, Brad Stone, Young Joo Kim, and John Ravits
- Subjects
Male ,Biology ,Mice ,03 medical and health sciences ,Exon ,0302 clinical medicine ,Cell-matrix adhesion ,Gene expression ,Cell Adhesion ,Genetics ,Animals ,Humans ,Compartment (development) ,Cell adhesion ,Molecular Biology ,Genetics (clinical) ,Aged ,030304 developmental biology ,Aged, 80 and over ,Motor Neurons ,Regulation of gene expression ,0303 health sciences ,Amyotrophic Lateral Sclerosis ,Alternative splicing ,Exons ,Articles ,General Medicine ,Middle Aged ,Molecular biology ,Extracellular Matrix ,3. Good health ,Cell biology ,Alternative Splicing ,Gene Expression Regulation ,RNA splicing ,Female ,030217 neurology & neurosurgery - Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by progressive weakness from loss of motor neurons. The fundamental pathogenic mechanisms are unknown and recent evidence is implicating a significant role for abnormal exon splicing and RNA processing. Using new comprehensive genomic technologies, we studied exon splicing directly in 12 sporadic ALS and 10 control lumbar spinal cords acquired by a rapid autopsy system that processed nervous systems specifically for genomic studies. ALS patients had rostral onset and caudally advancing disease and abundant residual motor neurons in this region. We created two RNA pools, one from motor neurons collected by laser capture microdissection and one from the surrounding anterior horns. From each, we isolated RNA, amplified mRNA, profiled whole-genome exon splicing, and applied advanced bioinformatics. We employed rigorous quality control measures at all steps and validated findings by qPCR. In the motor neuron enriched mRNA pool, we found two distinct cohorts of mRNA signals, most of which were up-regulated: 148 differentially expressed genes (Por= 10(-3)) and 411 aberrantly spliced genes (Por= 10(-5)). The aberrantly spliced genes were highly enriched in cell adhesion (Por= 10(-57)), especially cell-matrix as opposed to cell-cell adhesion. Most of the enriching genes encode transmembrane or secreted as opposed to nuclear or cytoplasmic proteins. The differentially expressed genes were not biologically enriched. In the anterior horn enriched mRNA pool, we could not clearly identify mRNA signals or biological enrichment. These findings, perturbed and up-regulated cell-matrix adhesion, suggest possible mechanisms for the contiguously progressive nature of motor neuron degeneration. Data deposition: GeneChip raw data (CEL-files) have been deposited for public access in the Gene Expression Omnibus (GEO), www.ncbi.nlm.nih.gov/geo, accession number GSE18920.
- Published
- 2009
40. Akt blocks ligand binding and protects against expanded polyglutamine androgen receptor toxicity
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Brian W. Howell, Maria Pennuto, Jessica E. Young, Albert R. La Spada, Phebe L. Brenne, Kenneth H. Fischbeck, Barrington G. Burnett, and Isabella Palazzolo
- Subjects
Transcriptional Activation ,medicine.medical_specialty ,Molecular Sequence Data ,Biology ,Ligands ,Phosphatidylinositol 3-Kinases ,Molecular Biology ,Genetics ,Genetics (clinical) ,Internal medicine ,Chlorocebus aethiops ,medicine ,Animals ,Humans ,Amino Acid Sequence ,Insulin-Like Growth Factor I ,Receptor ,Protein kinase B ,DNA Repeat Expansion ,COS cells ,Sequence Homology, Amino Acid ,General Medicine ,Polyglutamine tract ,medicine.disease ,Cell biology ,Androgen receptor ,Spinal and bulbar muscular atrophy ,Endocrinology ,Receptors, Androgen ,COS Cells ,Toxicity ,Phosphorylation ,Peptides ,Proto-Oncogene Proteins c-akt - Abstract
Spinal and bulbar muscular atrophy (SBMA) is a progressive neurodegenerative disease caused by an expansion of the polyglutamine tract in the androgen receptor (AR). Here, we investigated the regulation of AR phosphorylation in order to understand factors that may modify SBMA disease progression. We show that expanded polyglutamine AR is phosphorylated by Akt. Substitution of the AR at two Akt consensus sites, S215 and S792, with aspartate, which mimics phosphorylation, reduces ligand binding, ligand-dependent nuclear translocation, transcriptional activation and toxicity of expanded polyglutamine AR. Co-expression of constitutively active Akt and the AR has similar consequences, which are blocked by alanine substitutions at residues 215 and 792. Furthermore, in motor neuron-derived MN-1 cells toxicity associated with polyglutamine-expanded AR is rescued by co-expression with Akt. Insulin-like growth factor-1 (IGF-1) stimulation, which activates several cell survival promoting pathways, also reduces toxicity of the expanded polyglutamine AR in MN-1 cells, in a manner dependent upon phospho-inositol-3-kinase. IGF-1 rescue of AR toxicity is diminished by alanine substitutions at the Akt consensus sites. These results highlight potential targets for therapeutic intervention in SBMA.
- Published
- 2007
41. Nemo-like kinase is a novel regulator of spinal and bulbar muscular atrophy
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Hiroshi Kokubu, Janghoo Lim, Constanza J. Cortes, Albert R. La Spada, Helen C. Miranda, and Tiffany W. Todd
- Subjects
QH301-705.5 ,Science ,Mutant ,Regulator ,Protein Serine-Threonine Kinases ,Biology ,General Biochemistry, Genetics and Molecular Biology ,Cell Line ,Mice ,nemo-like kinase ,medicine ,Animals ,Humans ,Phosphorylation ,Biology (General) ,mouse ,Genetics ,spinal and bulbar muscular atrophy ,General Immunology and Microbiology ,Histocytochemistry ,Mechanism (biology) ,Kinase ,Muscles ,General Neuroscience ,neuromuscular disease ,General Medicine ,medicine.disease ,Survival Analysis ,Phenotype ,Muscular Disorders, Atrophic ,3. Good health ,Cell biology ,Androgen receptor ,Spinal and bulbar muscular atrophy ,polyglutamine disease ,Spinal Cord ,Receptors, Androgen ,Medicine ,Drosophila ,Mitogen-Activated Protein Kinases ,Protein Processing, Post-Translational ,Research Article ,Neuroscience - Abstract
Spinal and bulbar muscular atrophy (SBMA) is a progressive neuromuscular disease caused by polyglutamine expansion in the androgen receptor (AR) protein. Despite extensive research, the exact pathogenic mechanisms underlying SBMA remain elusive. In this study, we present evidence that Nemo-like kinase (NLK) promotes disease pathogenesis across multiple SBMA model systems. Most remarkably, loss of one copy of Nlk rescues SBMA phenotypes in mice, including extending lifespan. We also investigated the molecular mechanisms by which NLK exerts its effects in SBMA. Specifically, we have found that NLK can phosphorylate the mutant polyglutamine-expanded AR, enhance its aggregation, and promote AR-dependent gene transcription by regulating AR-cofactor interactions. Furthermore, NLK modulates the toxicity of a mutant AR fragment via a mechanism that is independent of AR-mediated gene transcription. Our findings uncover a crucial role for NLK in controlling SBMA toxicity and reveal a novel avenue for therapy development in SBMA. DOI: http://dx.doi.org/10.7554/eLife.08493.001, eLife digest Spinal and bulbar muscular atrophy (SBMA) is an inherited disease that eventually leads to degeneration in motor neurons and weakness in muscles. It is caused by a specific genetic mutation in the gene that encodes the androgen receptor protein, which leads to the production of a mutant protein that is larger than normal. Similar mutations in other genes can lead to the development of other so-called ‘polyglutamine’ diseases such as Huntington's disease and spinocerebellar ataxia. However, the precise details of how these mutations lead to disease symptoms are not known, and there are currently no effective ways of treating these conditions. Previous research has shown that an enzyme called Nemo-like kinase (or NLK for short) regulates the normal androgen receptor in cancer cells. NLK has kinase activity, that is, it adds phosphate molecules to other proteins to regulate their activity. Todd et al. used human cells, fruit flies, and mice as model systems to investigate whether NLK is involved in the development of SBMA. The experiments show that NLK promotes the development of features associated with SBMA in all three models. The kinase activity of NLK is required for these features to develop. Todd et al. also found that NLK can bind to and add phosphate molecules to the mutant version of the androgen receptor protein. This causes the mutant androgen receptor proteins to accumulate and increases the ability of the mutant proteins to activate particular genes. Todd et al.'s findings suggest that NLK promotes the development of SBMA by interacting with the mutant androgen receptor. Previous studies have shown that NLK is able to modulate the development of spinocerebellar ataxia type 1, which suggests that NLK may also play an important role in other polyglutamine diseases. The next challenge will be to fully understand the role of NLK in these diseases, which may aid future efforts to develop new treatments. DOI: http://dx.doi.org/10.7554/eLife.08493.002
- Published
- 2015
42. Thermoregulatory and metabolic defects in Huntington's disease transgenic mice implicate PGC-1α in Huntington's disease neurodegeneration
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Andrew D. Strand, Gregory J. Morton, Eduardo R. Lazarowski, Randell T. Libby, Victor V. Pineda, Serge Luquet, Merle L. Gilbert, Terrence F. Satterfield, Richard P. Beyer, Ian R. Sweet, Theodor K. Bammler, Patrick Weydt, Michael W. Schwartz, Albert R. La Spada, Libin Cui, Dimitri Krainc, Annette C. Smith, Anne E. Torrence, and Courtney N. Easley
- Subjects
Genetically modified mouse ,medicine.medical_specialty ,Huntingtin ,Transcription, Genetic ,Physiology ,HUMDISEASE ,Adipose tissue ,Mice, Transgenic ,Mitochondrion ,Biology ,MOLNEURO ,Body Temperature ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Adipose Tissue, Brown ,Huntington's disease ,Internal medicine ,Brown adipose tissue ,medicine ,Animals ,Molecular Biology ,Cells, Cultured ,Heat-Shock Proteins ,030304 developmental biology ,Genetics ,0303 health sciences ,Neurodegeneration ,Cell Biology ,medicine.disease ,Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha ,Thermogenin ,Mitochondria ,3. Good health ,Disease Models, Animal ,Huntington Disease ,Endocrinology ,medicine.anatomical_structure ,030217 neurology & neurosurgery ,Body Temperature Regulation ,Signal Transduction ,Transcription Factors - Abstract
Huntington's disease (HD) is a fatal, dominantly inherited disorder caused by polyglutamine repeat expansion in the huntingtin (htt) gene. Here, we observe that HD mice develop hypothermia associated with impaired activation of brown adipose tissue (BAT). Although sympathetic stimulation of PPARgamma coactivator 1alpha (PGC-1alpha) was intact in BAT of HD mice, uncoupling protein 1 (UCP-1) induction was blunted. In cultured cells, expression of mutant htt suppressed UCP-1 promoter activity; this was reversed by PGC-1alpha expression. HD mice showed reduced food intake and increased energy expenditure, with dysfunctional BAT mitochondria. PGC-1alpha is a known regulator of mitochondrial function; here, we document reduced expression of PGC-1alpha target genes in HD patient and mouse striatum. Mitochondria of HD mouse brain show reduced oxygen consumption rates. Finally, HD striatal neurons expressing exogenous PGC-1alpha were resistant to 3-nitropropionic acid treatment. Altered PGC-1alpha function may thus link transcription dysregulation and mitochondrial dysfunction in HD.
- Published
- 2006
43. β-synuclein modulates α-synuclein neurotoxicity by reducing α-synuclein protein expression
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Bryce L. Sopher, Pornprot Limprasert, Virginia M.-Y. Lee, John Q. Trojanowski, Ian V.J. Murray, Annette C. Smith, Yuxin Fan, and Albert R. La Spada
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Genetically modified mouse ,Genetics ,Alpha-synuclein ,Synucleinopathies ,Lewy body ,animal diseases ,Neurotoxicity ,General Medicine ,Biology ,medicine.disease ,nervous system diseases ,Cell biology ,chemistry.chemical_compound ,nervous system ,chemistry ,mental disorders ,Gene expression ,medicine ,Synuclein Family ,Beta-synuclein ,Molecular Biology ,Genetics (clinical) - Abstract
Parkinson's disease (PD) is a neurodegenerative disorder characterized by fibrillar aggregates of alpha-synuclein in characteristic inclusions known as "Lewy bodies". As mutations altering alpha-synuclein structure or increasing alpha-synuclein expression level can cause familial forms of PD or related Lewy body disorders, alpha-synuclein is believed to play a central role in the process of neuron toxicity, degeneration and death in "synucleinopathies". beta-synuclein is closely related to alpha-synuclein and has been shown to inhibit alpha-synuclein aggregation and ameliorate alpha-synuclein neurotoxicity. We generated beta-synuclein transgenic mice and observed a marked reduction in alpha-synuclein protein expression in the cortex of mice over-expressing beta-synuclein. This reduction in alpha-synuclein protein expression was not accompanied by decreases in alpha-synuclein mRNA expression. Using the prion protein promoter alpha-synuclein A53T mouse model of PD, we demonstrated that over-expression of beta-synuclein could retard the progression of impaired motor performance, reduce alpha-synuclein aggregation and extend survival in doubly transgenic mice. We attributed the amelioration of alpha-synuclein neurotoxicity in such bigenic mice to the ability of beta-synuclein to reduce alpha-synuclein protein expression based upon I(125) autoradiography quantification. Our findings indicate that increased expression of beta-synuclein protein results in a reduction of alpha-synuclein protein expression. As increased expression of alpha-synuclein may cause or contribute to PD pathogenesis in sporadic and familial forms of disease, this observation has important implications for the development of therapies for PD.
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- 2006
44. Silencing Polyglutamine Degeneration with RNAi
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Nancy M. Bonini and Albert R. La Spada
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Genetics ,Neuroscience(all) ,General Neuroscience ,Transgene ,Neurodegenerative Diseases ,Degeneration (medical) ,Disease ,Biology ,Therapeutic approach ,RNA interference ,Animals ,Humans ,Gene silencing ,Disease process ,Gene Silencing ,RNA, Small Interfering ,Allele - Abstract
Nine dominantly inherited neurodegenerative diseases are caused by expansion of a CAG repeat encoding glutamine. An important development in the study of such "polyglutamine" diseases was the realization that merely shutting off expression of a disease-encoding transgene could arrest progression in animal models with significant disease pathology. Such studies opened the door to a powerful new therapeutic approach now being pioneered: silencing of the dominant disease allele by RNA-mediated interference (RNAi), for the arrest--and potential reversal--of the disease process.
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- 2005
45. A SCA7 CAG/CTG repeat expansion is stable in Drosophila melanogaster despite modulation of genomic context and gene dosage
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Alexander J. Whitworth, Stephen M. Jackson, Randell T. Libby, Jessica C. Greene, Leo J. Pallanck, Sandy L. Baccam, and Albert R. La Spada
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congenital, hereditary, and neonatal diseases and abnormalities ,Candidate gene ,Flap Endonucleases ,Quantitative Trait Loci ,Gene Dosage ,Nerve Tissue Proteins ,Context (language use) ,Biology ,Gene dosage ,Genomic Instability ,Animals, Genetically Modified ,Proliferating Cell Nuclear Antigen ,Genetics ,medicine ,Animals ,Drosophila Proteins ,Gene ,Spinocerebellar Degenerations ,Ataxin-7 ,Genome ,DNA ,General Medicine ,medicine.disease ,biology.organism_classification ,Disease Models, Animal ,DNA Repair Enzymes ,Drosophila melanogaster ,Dynamic mutation ,Spinocerebellar ataxia ,Trinucleotide Repeat Expansion ,Trinucleotide repeat expansion - Abstract
CAG and CTG repeat expansions are the cause of at least a dozen inherited neurological disorders. In these so-called "dynamic mutation" diseases, the expanded repeats display dramatic genetic instability, changing in size when transmitted through the germline and within somatic tissues. As the molecular basis of the repeat instability process remains poorly understood, modeling of repeat instability in model organisms has provided some insights into potentially involved factors, implicating especially replication and repair pathways. Studies in mice have also shown that the genomic context of the repeat sequence is required for CAG/CTG repeat instability in the case of spinocerebellar ataxia type 7 (SCA7), one of the most unstable of all CAG/CTG repeat disease loci. While most studies of repeat instability have taken a candidate gene approach, unbiased screens for factors involved in trinucleotide repeat instability have been lacking. We therefore attempted to use Drosophila melanogaster to model expanded CAG repeat instability by creating transgenic flies carrying trinucleotide repeat expansions, deriving flies with SCA7 CAG90 repeats in cDNA and genomic context. We found that SCA7 CAG90 repeats are stable in Drosophila, regardless of context. To screen for genes whose reduced function might destabilize expanded CAG repeat tracts in Drosophila, we crossed the SCA7 CAG90 repeat flies with various deficiency stocks, including lines lacking genes encoding the orthologues of flap endonuclease-1, PCNA, and MutS. In all cases, perfect repeat stability was preserved, suggesting that Drosophila may not be a suitable system for determining the molecular basis of SCA7 CAG repeat instability.
- Published
- 2005
46. Synuclein gene alterations in dementia with Lewy bodies
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Miho Murata, Akiyoshi Kakita, Hiroaki Ohtake, Osamu Onodera, Atsushi Ishikawa, Pornprot Limprasert, Lauren T. Bonner, John Q. Trojanowski, Jiro Idezuka, A. R. La Spada, Shoji Tsuji, Haruhiko Takahashi, James B. Leverenz, Tatsushi Toda, Virginia M.-Y. Lee, Y. Fan, Thomas D. Bird, Ian V.J. Murray, and Debby W. Tsuang
- Subjects
Male ,Cystic Fibrosis ,animal diseases ,DNA Mutational Analysis ,Mice ,chemistry.chemical_compound ,Japan ,Thrombophilia ,Aged, 80 and over ,Genetics ,education.field_of_study ,Parkinson Disease ,Middle Aged ,Penetrance ,Pedigree ,Disease Progression ,alpha-Synuclein ,Female ,Lewy Body Disease ,Washington ,Molecular Sequence Data ,Population ,Mutation, Missense ,Synucleins ,Nerve Tissue Proteins ,Biology ,beta-Synuclein ,Species Specificity ,mental disorders ,medicine ,Animals ,Humans ,Point Mutation ,Genetic Predisposition to Disease ,Amino Acid Sequence ,Allele ,Codon ,education ,Gene ,Aged ,Brain Chemistry ,Alpha-synuclein ,Sequence Homology, Amino Acid ,Dementia with Lewy bodies ,Point mutation ,medicine.disease ,Rats ,nervous system diseases ,Amino Acid Substitution ,nervous system ,chemistry ,Cattle ,Neurology (clinical) ,Beta-synuclein ,Sequence Alignment - Abstract
Objective: To determine whether mutations in the genes for α-synuclein or β-synuclein are responsible for dementia with Lewy bodies (DLB), a disorder closely related to Parkinson disease (PD). Methods: The authors ascertained 33 sporadic cases of DLB and 10 kindreds segregating DLB. DNA samples from the 43 index cases were screened for alterations in the genes for α-synuclein and β-synuclein, as α-synuclein alterations cause PD and β-synuclein may modulate α-synuclein aggregation and neurotoxicity. Results: Two amino acid alterations were identified in unrelated DLB index cases: a valine to methionine substitution at codon 70 (V70M) and a proline to histidine substitution at codon 123 (P123H), both in the β-synuclein gene. These amino acid substitutions occur at conserved residues in highly conserved regions of the β-synuclein protein. Screening of at least 660 chromosomes from control subjects matched to the patients’ population groups failed to identify another V70M or P123H allele. Cosegregation analysis of an extended pedigree segregating the P123H β-synuclein alteration suggested that it is a dominant trait with reduced penetrance or a risk factor polymorphism. Histopathology and immunohistochemistry analysis of index case brain sections revealed widespread Lewy body pathology and α-synuclein aggregation without evidence of β-synuclein aggregation. Conclusion: Mutations in the β-synuclein gene may predispose to DLB.
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- 2004
47. Dynamic mutations on the move in Banff
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Albert R. La Spada, Robert I. Richards, and Bé Wieringa
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Human disease ,Evolutionary biology ,Genetics ,Microsatellite ,Biology ,Trinucleotide repeat expansion - Abstract
Earlier this year, the 4th International Meeting on Unstable Microsatellites and Human Disease highlighted how far and fast the research of diseases associated with expanded repeats has advanced, and spotlighted the remaining recalcitrant problems.
- Published
- 2004
48. Polyglutamines Placed into Context
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Albert R. La Spada and J. Paul Taylor
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Spinocerebellar Ataxia Type 1 ,Tyrosine 3-Monooxygenase ,Neuroscience(all) ,Context (language use) ,Disease ,Biology ,Protein Serine-Threonine Kinases ,Atrophy ,Cerebellum ,Proto-Oncogene Proteins ,medicine ,Animals ,Humans ,Spinocerebellar Ataxias ,Host protein ,Genetics ,Neurons ,Cell Death ,General Neuroscience ,Neurotoxicity ,medicine.disease ,Protein Structure, Tertiary ,14-3-3 Proteins ,Peptides ,Trinucleotide Repeat Expansion ,Neuroscience ,Proto-Oncogene Proteins c-akt - Abstract
Nine inherited neurodegenerative disorders result from polyglutamine expansions. Two recently published papers on spinocerebellar ataxia type 1, together with studies on spinobulbar muscular atrophy last year, indicate that host protein context is the key arbiter of polyglutamine disease protein toxicity. This insight may represent the most important development in the field since the recognition of nuclear inclusions or the propensity of polyglutamine to aggregate. Indeed, an intimate and inextricable relationship may exist between polyglutamine neurotoxicity and the normal interactions, domains, modifications, and functions of the respective disease proteins.
- Published
- 2003
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49. Targeted next-generation sequencing detects novel gene–phenotype associations and expands the mutational spectrum in cardiomyopathies
- Author
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Graziano Pesole, Stefano Favale, Rita Leonarda Musci, Vito Marangelli, Matteo Chiara, Cinzia Forleo, Andrea Igoren Guaricci, Sandro Sorrentino, Caterina Manzari, Delia De Santis, Anna Maria D'Erchia, Massimo Iacoviello, and Antonino La Spada
- Subjects
Male ,0301 basic medicine ,Genetic Screens ,Gene Identification and Analysis ,Cardiomyopathy ,lcsh:Medicine ,030204 cardiovascular system & hematology ,Bioinformatics ,Database and Informatics Methods ,0302 clinical medicine ,PSEN2 ,Medicine and Health Sciences ,Child ,lcsh:Science ,Genetics ,Multidisciplinary ,Hypertrophic cardiomyopathy ,High-Throughput Nucleotide Sequencing ,Dilated cardiomyopathy ,Genomics ,Middle Aged ,Genomic Databases ,3. Good health ,Phenotypes ,Phenotype ,Neurology ,Female ,Cardiomyopathies ,Research Article ,Adult ,Adolescent ,Cardiology ,Biology ,Research and Analysis Methods ,Sudden death ,Young Adult ,03 medical and health sciences ,ANK2 ,medicine ,Humans ,Genetic Association Studies ,lcsh:R ,Biology and Life Sciences ,Computational Biology ,Human Genetics ,Genome Analysis ,medicine.disease ,Human genetics ,Biological Databases ,030104 developmental biology ,Mutation Databases ,Mutation ,Genetics of Disease ,Channelopathies ,lcsh:Q ,Genetic screen - Abstract
Cardiomyopathies are a heterogeneous group of primary diseases of the myocardium, including hypertrophic cardiomyopathy (HCM), dilated cardiomyopathy (DCM), and arrhythmogenic right ventricular cardiomyopathy (ARVC), with higher morbidity and mortality. These diseases are genetically diverse and associated with rare mutations in a large number of genes, many of which overlap among the phenotypes. To better investigate the genetic overlap between these three phenotypes and to identify new genotype-phenotype correlations, we designed a custom gene panel consisting of 115 genes known to be associated with cardiomyopathic phenotypes and channelopathies. A cohort of 38 unrelated patients, 16 affected by DCM, 14 by HCM and 8 by ARVC, was recruited for the study on the basis of more severe phenotypes and family history of cardiomyopathy and/or sudden death. We detected a total of 142 rare variants in 40 genes, and all patients were found to be carriers of at least one rare variant. Twenty-eight of the 142 rare variants were also predicted as potentially pathogenic variants and found in 26 patients. In 23 out of 38 patients, we found at least one novel potential gene-phenotype association. In particular, we detected three variants in OBSCN gene in ARVC patients, four variants in ANK2 gene and two variants in DLG1, TRPM4, and AKAP9 genes in DCM patients, two variants in PSEN2 gene and four variants in AKAP9 gene in HCM patients. Overall, our results confirmed that cardiomyopathic patients could carry multiple rare gene variants; in addition, our investigation of the genetic overlap among cardiomyopathies revealed new gene-phenotype associations. Furthermore, as our study confirms, data obtained using targeted next-generation sequencing could provide a remarkable contribution to the molecular diagnosis of cardiomyopathies, early identification of patients at risk for arrhythmia development, and better clinical management of cardiomyopathic patients.
- Published
- 2017
50. Proteolytic cleavage of ataxin-7 promotes SCA7 retinal degeneration and neurological dysfunction
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Stephan J. Guyenet, Sara K. Custer, Bryce L. Sopher, Amy Lin, Sylvia F. Chen, Lisa M. Ellerby, Albert R. La Spada, and Shona S. Mookerjee
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Retinal degeneration ,Genetically modified mouse ,Ataxin 7 ,Proteolysis ,Mice, Transgenic ,Cleavage (embryo) ,Mice ,Purkinje Cells ,Genetics ,medicine ,Animals ,Humans ,Promoter Regions, Genetic ,Molecular Biology ,Genetics (clinical) ,Caspase ,Ataxin-7 ,Caspase 7 ,Aspartic Acid ,biology ,medicine.diagnostic_test ,Neurodegeneration ,Retinal Degeneration ,Neurodegenerative Diseases ,General Medicine ,Genetic Therapy ,Articles ,medicine.disease ,Molecular biology ,Cell biology ,Disease Models, Animal ,Phenotype ,Spinocerebellar ataxia ,biology.protein ,Peptides - Abstract
The neurodegenerative disorder spinocerebellar ataxia type 7 (SCA7) is caused by a polyglutamine (polyQ) expansion in the ataxin-7 protein, categorizing SCA7 as one member of a large class of heritable neurodegenerative proteinopathies. Cleavage of ataxin-7 by the protease caspase-7 has been demonstrated in vitro, and the accumulation of proteolytic cleavage products in SCA7 patients and mouse models has been identified as an early pathological change. However, it remains unknown whether a causal relationship exists between ataxin-7 proteolysis and in vivo SCA7 disease progression. To determine whether caspase cleavage is a critical event in SCA7 disease pathogenesis, we generated transgenic mice expressing polyQ-expanded ataxin-7 with a second-site mutation (D266N) to prevent caspase-7 proteolysis. When we compared SCA7-D266N mice with SCA7 mice lacking the D266N mutation, we found that SCA7-D266N mice exhibited improved motor performance, reduced neurodegeneration and substantial lifespan extension. Our findings indicate that proteolysis at the D266 caspase-7 cleavage site is an important mediator of ataxin-7 neurotoxicity, suggesting that inhibition of caspase-7 cleavage of polyQ-ataxin-7 may be a promising therapeutic strategy for this untreatable disorder.
- Published
- 2014
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