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Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disorder typically characterized by insoluble inclusions of hyperphosphorylated TDP-43. The mechanisms underlying toxic TDP-43 accumulation are not understood. Persistent activation of p38 mitogen-activated protein kinase (MAPK) is implicated in ALS. However, it is unclear how p38 MAPK affects TDP-43 proteinopathy. Here, we show that p38α MAPK inhibition reduces pathological TDP-43 phosphorylation, aggregation, cytoplasmic mislocalization, and neurotoxicity. Remarkably, p38α MAPK inhibition mitigates aberrant TDP-43 phenotypes in diverse ALS patient-derived motor neurons. p38α MAPK phosphorylates TDP-43 at pathological S409/S410 and S292, which reduces TDP-43 liquid-liquid phase separation (LLPS) but allows pathological TDP-43 aggregation. Moreover, we establish that PRMT1 methylates TDP-43 at R293. Importantly, S292 phosphorylation reduces R293 methylation, and R293 methylation reduces S409/S410 phosphorylation. Notably, R293 methylation permits TDP-43 LLPS and reduces pathological TDP-43 aggregation. Thus, strategies to reduce p38α-mediated TDP-43 phosphorylation and promote PRMT1-mediated R293 methylation could have therapeutic utility for ALS and related TDP-43 proteinopathies., Competing Interests: Declaration of interests H.J.W., D.G.B., and N.J.B. were full-time employees and shareholders of AstraZeneca at the time these studies were conducted. S.J.M. is a consultant for SAGE Therapeutics and AstraZeneca, relationships that are regulated by Tufts University., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Background: Achieving a medical professorship marks a significant step in a doctor's academic career, associated with a significant level of responsibility and obligations. The requirements to obtain a medical professorship in Germany vary significantly., Material and Methods: Based on an online search, we studied the statutes and regulations of medical faculties in Germany to determine the requirements for habilitation and an extraordinary professorship within Germany. All 38 German medical faculties were included. The evaluation was carried out for performance requirements in the areas of teaching and research., Results: The general requirement for a habilitation application is the completion of the medical specialist certification examination. On average, 2.3 years of teaching activity are expected. The minimum number of teaching hours averages 2.6 weekly semester hours. An average of at least 11 publications are required. Of these, an average of 7 must be written as first or last author. For an extraordinary professorship, an average of 4.4 years (min. 2, max. 6) of teaching activity after habilitation is required. The minimum number of teaching hours in semester hours averages 1.9 hours (min. 1, max. 2). The minimum number of publications averages 9 publications (min. 4, max. 24), of which an average of 6.3 must be written as first or last author., Conclusion: The requirements for habilitation and extraordinary professorship in Germany vary, especially with a view to publications and teaching. Depending on the faculty, lower publication numbers can be compensated by higher "impact factors". Furthermore, there is no national standardisation and comparability in the field of medical academic graduations., Competing Interests: Die Autorinnen/Autoren geben an, dass kein Interessenkonflikt besteht., (Thieme. All rights reserved.)

Understanding the normal function of the Huntingtin (HTT) protein is of significance in the design and implementation of therapeutic strategies for Huntington's disease (HD). Expansion of the CAG repeat in the HTT gene, encoding an expanded polyglutamine (polyQ) repeat within the HTT protein, causes HD and may compromise HTT's normal activity contributing to HD pathology. Here, we investigated the previously defined role of HTT in autophagy specifically through studying HTT's association with ubiquitin. We find that HTT interacts directly with ubiquitin in vitro. Tandem affinity purification was used to identify ubiquitinated and ubiquitin-associated proteins that copurify with a HTT N-terminal fragment under basal conditions. Copurification is enhanced by HTT polyQ expansion and reduced by mimicking HTT serine 421 phosphorylation. The identified HTT-interacting proteins include RNA-binding proteins (RBPs) involved in mRNA translation, proteins enriched in stress granules, the nuclear proteome, the defective ribosomal products (DRiPs) proteome and the brain-derived autophagosomal proteome. To determine whether the proteins interacting with HTT are autophagic targets, HTT knockout (KO) cells and immunoprecipitation of lysosomes were used to investigate autophagy in the absence of HTT. HTT KO was associated with reduced abundance of mitochondrial proteins in the lysosome, indicating a potential compromise in basal mitophagy, and increased lysosomal abundance of RBPs which may result from compensatory up-regulation of starvation-induced macroautophagy. We suggest HTT is critical for appropriate basal clearance of mitochondrial proteins and RBPs, hence reduced HTT proteostatic function with mutation may contribute to the neuropathology of HD., Competing Interests: Competing interests statement:The authors declare no competing interest.

Background: Deutetrabenazine is approved for adults with tardive dyskinesia (TD). Data based on underlying psychiatric condition and baseline dopamine receptor antagonist (DRA) use are limited., Methods: Patients with TD who completed parent studies ARM-TD or AIM-TD were eligible for the 3-year, open-label extension study (RIM-TD; NCT02198794). In RIM-TD, deutetrabenazine was titrated based on dyskinesia control and tolerability. In this post hoc analysis of RIM-TD, total motor Abnormal Involuntary Movement Scale (AIMS) score and adverse events (AEs) were analyzed by underlying condition and DRA use at parent study baseline., Results: Of 343 patients enrolled in RIM-TD, 336 were included in the analysis by underlying condition, and 337 were included in the analysis by DRA use. One hundred eighty-nine of 205 (92%) patients with psychotic disorders (schizophrenia/schizoaffective disorder) and 65 of 131 (50%) with mood and other disorders (depression/bipolar disorder/other) were receiving a DRA. Mean (SE) deutetrabenazine doses at week 145 were 40.4 (1.13), 38.5 (1.21), 39.9 (1.00), and 38.5 (1.48) mg/d for patients with psychotic disorders, those with mood and other disorders, and those receiving DRAs or not, respectively. Mean (SD) changes in total motor AIMS score from this study baseline to week 145 were -6.3 (4.53), -7.1 (4.92), -6.1 (4.42), and -7.5 (5.19). Exposure-adjusted incidence rates (number of AEs/patient-years) of AEs were similar across groups: any (1.02, 1.71, 1.08, 1.97), serious (0.10, 0.12, 0.10, 0.12), and leading to discontinuation (0.07, 0.05, 0.06, 0.05)., Conclusions: Long-term deutetrabenazine provided clinically meaningful improvements in TD-related movements, with a favorable benefit-risk profile, regardless of underlying condition or DRA use., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc.)

Neurodegenerative diseases are complex and progressive, posing challenges to their study and understanding. Recent advances in microscopy imaging technologies have enabled the exploration of neurons in three spatial dimensions (3D) over time (4D). When applied to 3D cultures, tissues, or animals, these technologies can provide valuable insights into the dynamic and spatial nature of neurodegenerative diseases. This review focuses on the use of imaging techniques and neurodegenerative disease models to study neurodegeneration in 4D. Imaging techniques such as confocal microscopy, two-photon microscopy, miniscope imaging, light sheet microscopy, and robotic microscopy offer powerful tools to visualize and analyze neuronal changes over time in 3D tissue. Application of these technologies to in vitro models of neurodegeneration such as mouse organotypic culture systems and human organoid models provide versatile platforms to study neurodegeneration in a physiologically relevant context. Additionally, use of 4D imaging in vivo, including in mouse and zebrafish models of neurodegenerative diseases, allows for the investigation of early dysfunction and behavioral changes associated with neurodegeneration. We propose that these studies have the power to overcome the limitations of two-dimensional monolayer neuronal cultures and pave the way for improved understanding of the dynamics of neurodegenerative diseases and the development of effective therapeutic strategies., Competing Interests: Conflict of interest S. F. is the inventor of Robotic Microscopy Systems, US Patent 7,139,415 and Automated Robotic Microscopy Systems, US Patent Application 14/737,325, both assigned to the J. David Gladstone Institutes. A provisional US and EPO patent for the GEDI biosensor (inventors J. W. L. and S. F.) assigned to the J. David Gladstone Institutes has been placed GL2016 to 815, May 2019. S. F. and J. W. L. are co-founders of Operant Biopharma. The other author declares that they have no conflicts of interest with the contents of this article., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Excess gene dosage from chromosome 21 (chr21) causes Down syndrome (DS), spanning developmental and acute phenotypes in terminal cell types. Which phenotypes remain amenable to intervention after development is unknown. To address this question in a model of DS neurogenesis, we derived trisomy 21 (T21) human induced pluripotent stem cells (iPSCs) alongside, otherwise, isogenic euploid controls from mosaic DS fibroblasts and equipped one chr21 copy with an inducible XIST transgene. Monoallelic chr21 silencing by XIST is near-complete and irreversible in iPSCs. Differential expression reveals that T21 neural lineages and iPSCs share suppressed translation and mitochondrial pathways and activate cellular stress responses. When XIST is induced before the neural progenitor stage, T21 dosage correction suppresses a pronounced skew toward astrogenesis in neural differentiation. Because our transgene remains inducible in postmitotic T21 neurons and astrocytes, we demonstrate that XIST efficiently represses genes even after terminal differentiation, which will empower exploration of cell type-specific T21 phenotypes that remain responsive to chr21 dosage.

Amyotrophic Lateral Sclerosis (ALS), like many other neurodegenerative diseases, is highly heritable, but with only a small fraction of cases explained by monogenic disease alleles. To better understand sporadic ALS, we report epigenomic profiles, as measured by ATAC-seq, of motor neuron cultures derived from a diverse group of 380 ALS patients and 80 healthy controls. We find that chromatin accessibility is heavily influenced by sex, the iPSC cell type of origin, ancestry, and the inherent variance arising from sequencing. Once these covariates are corrected for, we are able to identify ALS-specific signals in the data. Additionally, we find that the ATAC-seq data is able to predict ALS disease progression rates with similar accuracy to methods based on biomarkers and clinical status. These results suggest that iPSC-derived motor neurons recapitulate important disease-relevant epigenomic changes., (© 2024. The Author(s).)

While challenging, identifying individuals displaying resilience to Alzheimer's disease (AD) and understanding the underlying mechanism holds great promise for the development of new therapeutic interventions to effectively treat AD. Down syndrome (DS), or trisomy 21, is the most common genetic cause of AD. Interestingly, some people with DS, despite developing AD neuropathology, show resilience to cognitive decline. Furthermore, DS individuals are at an increased risk of myeloid leukemia due to somatic mutations in hematopoietic cells. Recent studies indicate that somatic mutations in hematopoietic cells may lead to resilience to neurodegeneration. Microglia, derived from hematopoietic lineages, play a central role in AD etiology. We therefore hypothesize that microglia carrying the somatic mutations associated with DS myeloid leukemia may impart resilience to AD. Using CRISPR-Cas9 gene editing, we introduce a trisomy 21-linked hotspot CSF2RB A455D mutation into human pluripotent stem cell (hPSC) lines derived from both DS and healthy individuals. Employing hPSC-based in vitro microglia culture and in vivo human microglia chimeric mouse brain models, we show that in response to pathological tau, the CSF2RB A455D mutation suppresses microglial type-1 interferon signaling, independent of trisomy 21 genetic background. This mutation reduces neuroinflammation and enhances phagocytic and autophagic functions, thereby ameliorating senescent and dystrophic phenotypes in human microglia. Moreover, the CSF2RB A455D mutation promotes the development of a unique microglia subcluster with tissue repair properties. Importantly, human microglia carrying CSF2RB A455D provide protection to neuronal function, such as neurogenesis and synaptic plasticity in chimeric mouse brains where human microglia largely repopulate the hippocampus. When co-transplanted into the same mouse brains, human microglia with CSF2RB A455D mutation phagocytize and replace human microglia carrying the wildtype CSF2RB gene following pathological tau treatment. Our findings suggest that hPSC-derived CSF2RB A455D microglia could be employed to develop effective microglial replacement therapy for AD and other age-related neurodegenerative diseases, even without the need to deplete endogenous diseased microglia prior to cell transplantation., Competing Interests: Competing Financial Interests The authors declare no competing financial interests.

Translating high-confidence (hc) autism spectrum disorder (ASD) genes into viable treatment targets remains elusive. We constructed a foundational protein-protein interaction (PPI) network in HEK293T cells involving 100 hcASD risk genes, revealing over 1,800 PPIs (87% novel). Interactors, expressed in the human brain and enriched for ASD but not schizophrenia genetic risk, converged on protein complexes involved in neurogenesis, tubulin biology, transcriptional regulation, and chromatin modification. A PPI map of 54 patient-derived missense variants identified differential physical interactions, and we leveraged AlphaFold-Multimer predictions to prioritize direct PPIs and specific variants for interrogation in Xenopus tropicalis and human forebrain organoids. A mutation in the transcription factor FOXP1 led to reconfiguration of DNA binding sites and altered development of deep cortical layer neurons in forebrain organoids. This work offers new insights into molecular mechanisms underlying ASD and describes a powerful platform to develop and test therapeutic strategies for many genetically-defined conditions.

Spatial transcriptomics (ST) represents a pivotal advancement in biomedical research, enabling the transcriptional profiling of cells within their morphological context and providing a pivotal tool for understanding spatial heterogeneity in cancer tissues. However, current analytical approaches, akin to single-cell analysis, largely depend on gene expression, underutilizing the rich morphological information inherent in the tissue. We present a novel method integrating spatial transcriptomics and histopathological image data to better capture biologically meaningful patterns in patient data, focusing on aggressive cancer types such as glioblastoma and triple-negative breast cancer. We used a ResNet-based deep learning model to extract key morphological features from high-resolution whole-slide histology images. Spot-level PCA-reduced vectors of both the ResNet-50 analysis of the histological image and the spatial gene expression data were used in Louvain clustering to enable image-aware feature discovery. Assessment of features from image-aware clustering successfully pinpointed key biological features identified by manual histopathology, such as for regions of fibrosis and necrosis, as well as improved edge definition in EGFR-rich areas. Importantly, our combinatorial approach revealed crucial characteristics seen in histopathology that gene-expression-only analysis had missed.Supplemental Material: https://github.com/davcraig75/song_psb2014/blob/main/SupplementaryData.pdf.

Background: Tardive dyskinesia (TD) has a multidimensional impact on patients with TD and, as importantly, their caregivers. An online survey was developed and administered to assess patient and caregiver burden of TD. Survey participants were unpaid caregivers for patients with diagnoses of TD and schizophrenia, bipolar disorder, and/or major depressive disorder. Overall, 162 caregivers rated the 7-day impact of TD on the physical, psychological, and social functioning of patients and the impact of TD on these domains in their own lives and in their professional lives., Results: Across physical, psychological, and social domains, most caregivers (82.7%) reported that TD had severe impact on the cared-for patients, and 23.5% reported severe impact of TD in their own lives. Caregivers experienced 46.4% activity impairment, and caregivers who were employed (n = 136) experienced 49.5% overall work impairment because of TD-related caregiving., Conclusions: These results suggest that TD imposes substantial burden for both caregivers and patients., (© 2023. The Author(s).)

Actively avoiding fever is the only possibility to improve neurological outcome after cardiac arrest. It is uncertain if and which patients benefit from a lower target temperature. The ERC Guidelines in 2021 recommended targeted temperature management (TTM) for all patients after in- and out-of-hospital cardiac arrest with a target temperature of 32-36 °C for at least 24 hours. These recommendations were updated in 2022 by the ERC/ESICM Guidelines suggesting to avoid fever only within the first 72 hours after the event. Divergent results of recent trials lead to these guideline changes. The large TTM2 Trial in 2021 did not show a benefit neither in survival nor in neurological outcome in the group of hypothermia at 33°C compared to normothermia. Although leading to the updated guidelines, applying these study results to the German population is restricted as the rate of bystander cardiopulmonary resuscitation (CPR) or shockable rhythms is much lower in Germany. Further studies are needed to allow a better differentiation of subpopulations and to implement a more individual classification und therapy., Competing Interests: Die Autorinnen/Autoren geben an, dass kein Interessenkonflikt besteht., (Thieme. All rights reserved.)

DNA damage is a common cellular feature seen in cancer and neurodegenerative disease, but fast and accurate methods for quantifying DNA damage are lacking. Comet assays are a biochemical tool to measure DNA damage based on the migration of broken DNA strands towards a positive electrode, which creates a quantifiable 'tail' behind the cell. However, a major limitation of this approach is the time needed for analysis of comets in the images with available open-source algorithms. The requirement for manual curation and the laborious pre- and post-processing steps can take hours to days. To overcome these limitations, we developed AutoComet, a new open-source algorithm for comet analysis that utilizes automated comet segmentation and quantification of tail parameters. AutoComet first segments and filters comets based on size and intensity and then filters out comets without a well-connected head and tail, which significantly increases segmentation accuracy. Because AutoComet is fully automated, it minimizes curator bias and is scalable, decreasing analysis time over ten-fold, to less than 3 s per comet. AutoComet successfully detected statistically significant differences in tail parameters between cells with and without induced DNA damage, and was more comparable to the results of manual curation than other open-source software analysis programs. We conclude that the AutoComet algorithm provides a fast, unbiased and accurate method to quantify DNA damage that avoids the inherent limitations of manual curation and will significantly improve the ability to detect DNA damage., Competing Interests: Declaration of competing interest None., (Copyright © 2023. Published by Elsevier B.V.)

Social grouping increases survival in many species, including humans 1,2 . By contrast, social isolation generates an aversive state (loneliness) that motivates social seeking and heightens social interaction upon reunion 3-5 . The observed rebound in social interaction triggered by isolation suggests a homeostatic process underlying the control of social drive, similar to that observed for physiological needs such as hunger, thirst or sleep 3,6 . In this study, we assessed social responses in multiple mouse strains and identified the FVB/NJ line as exquisitely sensitive to social isolation. Using FVB/NJ mice, we uncovered two previously uncharacterized neuronal populations in the hypothalamic preoptic nucleus that are activated during social isolation and social rebound and that orchestrate the behavior display of social need and social satiety, respectively. We identified direct connectivity between these two populations of opposite function and with brain areas associated with social behavior, emotional state, reward, and physiological needs, and showed that animals require touch to assess the presence of others and fulfill their social need, thus revealing a brain-wide neural system underlying social homeostasis. These findings offer mechanistic insight into the nature and function of circuits controlling instinctive social need and for the understanding of healthy and diseased brain states associated with social context., Competing Interests: Competing interests. The authors declare no competing interests.

Using induced pluripotent stem cells (iPSCs) to understand the mechanisms of neurological disease holds great promise; however, there is a lack of well-curated lines from a large array of participants. Answer ALS has generated over 1,000 iPSC lines from control and amyotrophic lateral sclerosis (ALS) patients along with clinical and whole-genome sequencing data. The current report summarizes cell marker and gene expression in motor neuron cultures derived from 92 healthy control and 341 ALS participants using a 32-day differentiation protocol. This is the largest set of iPSCs to be differentiated into motor neurons, and characterization suggests that cell composition and sex are significant sources of variability that need to be carefully controlled for in future studies. These data are reported as a resource for the scientific community that will utilize Answer ALS data for disease modeling using a wider array of omics being made available for these samples., Competing Interests: Declaration of interests US patent 10,221,395-B2 has been granted describing a method for reprogramming blood to induced pluripotent stem cells. Apart from this issued patent filing, the authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Objective: To assess the physical, psychological, social, and professional impact of tardive dyskinesia (TD) on patients in the United States., Methods : An online survey (April 2020-June 2021) to assess patient burden of TD was developed using targeted literature review and interviews with clinicians, patients, and caregivers. Survey participants (aged ≥ 18 years) with current diagnoses of TD and schizophrenia, bipolar disorder, or major depressive disorder rated the 7-day impact of TD on their physical, psychological, and social functioning via Likert scales (scored from 1 [least impact] to 5 [most impact]). Impact scores were calculated and summarized descriptively overall by self-reported disease severity and underlying disease. Participants also completed the Work Productivity and Activity Impairment Questionnaire and reported the impact of TD on their underlying psychiatric condition., Results : Overall, 269 patients (mean [SD] age = 40.6 years [9.9]; 74.7% employed) responded to the survey. Mean (SD) impact scores of 3.1 (0.9), 3.5 (1.0), and 3.2 (1.1) were reported in the physical, psychological, and social domains, respectively, and scores increased with reported TD symptom severity. Patients with underlying schizophrenia reported the highest burden for all domains. Patients reported 66.2% activity impairment because of TD. Employed patients (n = 193) indicated 29.1% absenteeism, 68.4% presenteeism, and 73.5% overall work impairment. Over one-third of patients reported skipping/reducing (48.4%) or stopping (39.3%) their antipsychotic medication and stopping visits to clinicians treating their underlying condition (35.7%) because of TD., Conclusion : TD imposes a substantial burden on patients' physical, psychological, social, and professional lives and impacts management of their underlying condition., (© Copyright 2023 Physicians Postgraduate Press, Inc.)

The condition of having a healthy, functional proteome is known as protein homeostasis, or proteostasis. Establishing and maintaining proteostasis is the province of the proteostasis network, approximately 2,700 components that regulate protein synthesis, folding, localization, and degradation. The proteostasis network is a fundamental entity in biology that is essential for cellular health and has direct relevance to many diseases of protein conformation. However, it is not well defined or annotated, which hinders its functional characterization in health and disease. In this series of manuscripts, we aim to operationally define the human proteostasis network by providing a comprehensive, annotated list of its components. We provided in a previous manuscript a list of chaperones and folding enzymes as well as the components that make up the machineries for protein synthesis, protein trafficking into and out of organelles, and organelle-specific degradation pathways. Here, we provide a curated list of 838 unique high-confidence components of the autophagy-lysosome pathway, one of the two major protein degradation systems in human cells.

The Foundational Data Initiative for Parkinson Disease (FOUNDIN-PD) is an international collaboration producing fundamental resources for Parkinson disease (PD). FOUNDIN-PD generated a multi-layered molecular dataset in a cohort of induced pluripotent stem cell (iPSC) lines differentiated to dopaminergic (DA) neurons, a major affected cell type in PD. The lines were derived from the Parkinson's Progression Markers Initiative study, which included participants with PD carrying monogenic PD variants, variants with intermediate effects, and variants identified by genome-wide association studies and unaffected individuals. We generated genetic, epigenetic, regulatory, transcriptomic, and longitudinal cellular imaging data from iPSC-derived DA neurons to understand molecular relationships between disease-associated genetic variation and proximate molecular events. These data reveal that iPSC-derived DA neurons provide a valuable cellular context and foundational atlas for modeling PD genetic risk. We have integrated these data into a FOUNDIN-PD data browser as a resource for understanding the molecular pathogenesis of PD.

Haploinsufficiency of progranulin (PGRN) causes frontotemporal dementia (FTD), a devastating neurodegenerative disease with no effective treatment. PGRN is required for efficient proteostasis, as loss of neuronal PGRN results in dysfunctional lysosomes and impaired clearance and cytoplasmic aggregation of TDP-43, a protein involved in neurodegeneration in FTD. These and other events lead to neurodegeneration and neuroinflammation. However, the detailed mechanisms leading to protein dyshomeostasis in PGRN-deficient cells remain unclear. We report here the development of human cell models of FTD with PGRN-deficiency to explore the molecular mechanisms underlying proteostasis breakdown and TDP-43 aggregation in FTD. Neurons differentiated from FTD patient induced pluripotent stem cells (iPSCs) have reduced PGRN levels, and the neurons recapitulate key disease features, including impaired lysosomal function, defective TDP-43 turnover and accumulation, neurodegeneration, and death. Proteomic analysis revealed altered levels of proteins linked to the autophagy-lysosome pathway (ALP) and the ubiquitin-proteasome system (UPS) in FTD patient neurons, providing new mechanistic insights into the link between PGRN-deficiency and disease pathobiology.

The National Institute of Health (NIH) Library of integrated network-based cellular signatures (LINCS) program is premised on the generation of a publicly available data resource of cell-based biochemical responses or "signatures" to genetic or environmental perturbations. NeuroLINCS uses human inducible pluripotent stem cells (hiPSCs), derived from patients and healthy controls, and differentiated into motor neuron cell cultures. This multi-laboratory effort strives to establish i) robust multi-omic workflows for hiPSC and differentiated neuronal cultures, ii) public annotated data sets and iii) relevant and targetable biological pathways of spinal muscular atrophy (SMA) and amyotrophic lateral sclerosis (ALS). Here, we focus on the proteomics and the quality of the developed workflow of hiPSC lines from 6 individuals, though epigenomics and transcriptomics data are also publicly available. Known and commonly used markers representing 73 proteins were reproducibly quantified with consistent expression levels across all hiPSC lines. Data quality assessments, data levels and metadata of all 6 genetically diverse human iPSCs analysed by DIA-MS are parsable and available as a high-quality resource to the public., (© 2023. The Author(s).)

Zika virus (ZIKV) infects fetal neural progenitor cells (NPCs) causing severe neurodevelopmental disorders in utero. Multiple pathways involved in normal brain development are dysfunctional in infected NPCs but how ZIKV centrally reprograms these pathways remains unknown. Here we show that ZIKV infection disrupts subcellular partitioning of host transcripts critical for neurodevelopment in NPCs and functionally link this process to the up-frameshift protein 1 (UPF1). UPF1 is an RNA-binding protein known to regulate decay of cellular and viral RNAs and is less expressed in ZIKV-infected cells. Using infrared crosslinking immunoprecipitation and RNA sequencing (irCLIP-Seq), we show that a subset of mRNAs loses UPF1 binding in ZIKV-infected NPCs, consistent with UPF1's diminished expression. UPF1 target transcripts, however, are not altered in abundance but in subcellular localization, with mRNAs accumulating in the nucleus of infected or UPF1 knockdown cells. This leads to diminished protein expression of FREM2, a protein required for maintenance of NPC identity. Our results newly link UPF1 to the regulation of mRNA transport in NPCs, a process perturbed during ZIKV infection., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Leon et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Neurotoxicity can be detected in live microscopy by morphological changes such as retraction of neurites, fragmentation, blebbing of the neuronal soma and ultimately the disappearance of fluorescently labeled neurons. However, quantification of these features is often difficult, low-throughput, and imprecise due to the overreliance on human curation. Recently, we showed that convolutional neural network (CNN) models can outperform human curators in the assessment of neuronal death from images of fluorescently labeled neurons, suggesting that there is information within the images that indicates toxicity but that is not apparent to the human eye. In particular, the CNN's decision strategy indicated that information within the nuclear region was essential for its superhuman performance. Here, we systematically tested this prediction by comparing images of fluorescent neuronal morphology from nuclear-localized fluorescent protein to those from freely diffused fluorescent protein for classifying neuronal death. We found that biomarker-optimized (BO-) CNNs could learn to classify neuronal death from fluorescent protein-localized nuclear morphology (mApple-NLS-CNN) alone, with super-human accuracy. Furthermore, leveraging methods from explainable artificial intelligence, we identified novel features within the nuclear-localized fluorescent protein signal that were indicative of neuronal death. Our findings suggest that the use of a nuclear morphology marker in live imaging combined with computational models such mApple-NLS-CNN can provide an optimal readout of neuronal death, a common result of neurotoxicity., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Wang, Linsley, Linsley, Lamstein and Finkbeiner.)

Background: In Parkinson's disease, postural instability and falls are of particular socioeconomic relevance. Although effective fall prevention and the prophylaxis of fall-related injuries depend on low-threshold symptom monitoring, validated instruments are lacking., Objectives: To develop a self-report questionnaire for the assessment of falls, near falls, fear of falling, fall-related injuries, and causes of falls for patients with Parkinson's disease (PwPD)., Methods: A pool of potential items was generated from a literature review and by discussion in an expert panel. The first version of the Dresden Fall Questionnaire (DREFAQ) was tested in a group of German-speaking movement disorder specialists as well as PwPD. The resulting 5-item questionnaire was assessed in a validation cohort of 36 PwPD who documented fall events and near-fall events in a calendar for 3 months and completed the DREFAQ at the end of the study. The questionnaire was subsequently used in a separate cohort of 46 PwPD to determine test-retest reliability and confirm the factor structure., Results: The DREFAQ showed good internal consistency (Cronbach's α = 0.84) and good test-retest reliability (intraclass correlation coefficient, 0.76; 95% confidence interval, 0.60-0.86). The total DREFAQ score showed good concurrent validity with fall events (Spearman's ρ = 0.82) and near-fall events (Spearman's ρ = 0.78) as determined by fall and near-fall diaries. Factor analysis revealed a 2-factor structure composed of near falls with fear of falling and severe falls with injuries., Conclusions: The DREFAQ is a reliable and valid 5-item questionnaire for determining the incidence of falls, near falls, fear of falling, fall-related injuries, and causes of falls in PwPD., (© 2022 The Authors. Movement Disorders Clinical Practice published by Wiley Periodicals LLC on behalf of Movement Disorder Society.)

A major advance in the study of Huntington's disease (HD) has been the development of human disease models employing induced pluripotent stem cells (iPSCs) derived from patients with HD. Because iPSCs provide an unlimited source of cells and can be obtained from large numbers of HD patients, they are a uniquely valuable tool for investigating disease mechanisms and for discovering potential disease-modifying therapeutics. Here, we summarize some of the important findings in HD pathophysiology that have emerged from studies of patient-derived iPSC lines. Because they retain the genome and actual disease mutations of the patient, they provide a cell source to investigate genetic contributions to the disease. iPSCs provide advantages over other disease models. While iPSC-based technology erases some epigenetic marks, newly developed transdifferentiation methods now let us investigate epigenetic factors that control expression of mutant huntingtin (mHTT). Human HD iPSC lines allow us to investigate how endogenous levels of mHTT affect cell health, in contrast to other models that often rely on overexpressing the protein. iPSCs can be differentiated into neurons and other disease-related cells such as astrocytes from different brain regions to study brain regional differences in the disease process, as well as the cell-cell dependencies involved in HD-associated neurodegeneration. They also serve as a tissue source to investigate factors that impact CAG repeat instability, which is involved in regional differences in neurodegeneration in the HD brain. Human iPSC models can serve as a powerful model system to identify genetic modifiers that may impact disease onset, progression, and symptomatology, providing novel molecular targets for drug discovery., Competing Interests: The authors declare that they have no competing interests.No competing interests were disclosed.No competing interests were disclosed., (Copyright: © 2022 Finkbeiner S et al.)

Repeat diseases, such as fragile X syndrome, myotonic dystrophy, Friedreich ataxia, Huntington disease, spinocerebellar ataxias, and some forms of amyotrophic lateral sclerosis, are caused by repetitive DNA sequences that are expanded in affected individuals. The age at which an individual begins to experience symptoms, and the severity of disease, are partially determined by the size of the repeat. However, the epigenetic state of the area in and around the repeat also plays an important role in determining the age of disease onset and the rate of disease progression. Many repeat diseases share a common epigenetic pattern of increased methylation at CpG islands near the repeat region. CpG islands are CG-rich sequences that are tightly regulated by methylation and are often found at gene enhancer or insulator elements in the genome. Methylation of CpG islands can inhibit binding of the transcriptional regulator CTCF, resulting in a closed chromatin state and gene down regulation. The downregulation of these genes leads to some disease-specific symptoms. Additionally, a genetic and epigenetic interplay is suggested by an effect of methylation on repeat instability, a hallmark of large repeat expansions that leads to increasing disease severity in successive generations. In this review, we will discuss the common epigenetic patterns shared across repeat diseases, how the genetics and epigenetics interact, and how this could be involved in disease manifestation. We also discuss the currently available stem cell and mouse models, which frequently do not recapitulate epigenetic patterns observed in human disease, and propose alternative strategies to study the role of epigenetics in repeat diseases., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Barbé and Finkbeiner.)