15 results on '"Sharon AVIRAM"'
Search Results
2. Induction of heparanase 2 (Hpa2) expression by stress is mediated by ATF3
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Neta Ilan, Ibrahim Knani, Miriam Gross-Cohen, Ami Aronheim, Ralph D. Sanderson, Preeti Singh, Israel Vlodavsky, and Sharon Aviram
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Regulation of gene expression ,ATF3 ,Activating Transcription Factor 3 ,Chemistry ,Heparan sulfate ,Article ,Cell biology ,chemistry.chemical_compound ,Tumor progression ,Neoplasms ,Gene expression ,Unfolded protein response ,Humans ,Heparanase ,Heparitin Sulfate ,Molecular Biology ,Transcription factor ,Glucuronidase - Abstract
Activity of heparanase, endoglycosidase that cleaves heparan sulfate side chains in heparan sulfate proteoglycans, is highly implicated in tumor progression and metastasis. Heparanase inhibitors are therefore being evaluated clinically as anti-cancer therapeutics. Heparanase 2 (Hpa2) is a close homolog of heparanase that lacks HS-degrading activity and functions as an endogenous inhibitor of heparanase. As a result, Hpa2 appears to attenuate tumor growth but mechanisms that regulate Hpa2 expression and determine the ratio between heparanase and Hpa2 are largely unknown. We have recently reported that the expression of Hpa2 is induced by endoplasmic reticulum (ER) and proteotoxic stresses, but the mechanism(s) underlying Hpa2 gene regulation was obscure. Here we expand the notion that Hpa2 is regulated by conditions of stress. We report that while ER and hypoxia, each alone, resulted in a 3-7 fold increase in Hpa2 expression, combining ER stress and hypoxia resulted in a noticeable, over 40-fold increase in Hpa2 expression. A prominent induction of Hpa2 expression was also quantified in cells exposed to heat shock, proteotoxic stress, lysosomal stress, and chemotherapy (cisplatin), strongly implying that Hpa2 is regulated by conditions of stress. Furthermore, analyses of the Hpa2 gene promoter led to the identification of activating-transcription-factor 3 (ATF3) as a transcription factor that mediates Hpa2 induction by stress, thus revealing, for the first time, a molecular mechanism that underlies Hpa2 gene regulation. Induction of Hpa2 and ATF3 by conditions of stress that often accompany the rapid expansion of tumors is likely translated to improved survival of cancer patients. more...
- Published
- 2021
Catalog
3. ATF3 and JDP2 deficiency in cancer associated fibroblasts promotes tumor growth via SDF-1 transcription
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Shimrit Avraham, Dvir Shechter, Yuval Shaked, Sharon Aviram, Ben Korin, and Ami Aronheim
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Cancer microenvironment ,0301 basic medicine ,Cancer Research ,Stromal cell ,Activating transcription factor ,Biology ,Article ,03 medical and health sciences ,0302 clinical medicine ,Cancer-Associated Fibroblasts ,Tumor Microenvironment ,Genetics ,Animals ,Humans ,Stromal tumor ,Cancer genetics ,Molecular Biology ,Transcription factor ,Bone Marrow Transplantation ,Cell Proliferation ,Mice, Knockout ,ATF3 ,Tumor microenvironment ,Activating Transcription Factor 3 ,Neoplasms, Experimental ,Xenograft Model Antitumor Assays ,Chemokine CXCL12 ,Cell biology ,Gene Expression Regulation, Neoplastic ,Mice, Inbred C57BL ,Repressor Proteins ,HEK293 Cells ,030104 developmental biology ,030220 oncology & carcinogenesis ,Cancer cell ,Blood Vessels ,Female - Abstract
The activating transcription factor 3 (ATF3) and the c-Jun dimerization protein 2 (JDP2) are members of the basic leucine zipper (bZIP) family of transcription factors. These proteins share a high degree of homology and both can activate or repress transcription. Deficiency of either one of them in the non-cancer host cells was shown to reduce metastases. As ATF3 and JDP2 compensate each other’s function, we studied the double deficiency of ATF3 and JDP2 in the stromal tumor microenvironment. Here, we show that mice with ATF3 and JDP2 double deficiency (designated thereafter dKO) developed larger tumors with high vascular perfusion and increased cell proliferation rate compared to wild type (WT) mice. We further identify that the underlying mechanism involves tumor associated fibroblasts which secrete high levels of stromal cell-derived factor 1 (SDF-1) in dKO fibroblasts. SDF-1 depletion in dKO fibroblasts dampened tumor growth and blood vessel perfusion. Furthermore, ATF3 and JDP2 were found to regulate SDF-1 transcription and secretion in fibroblasts, a phenomenon that is potentiated in the presence of cancer cells. Collectively, our results suggest that ATF3 and JDP2 regulate the expression of essential tumor promoting factors expressed by fibroblasts within the tumor microenvironment, and thus restrain tumor growth. more...
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- 2019
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4. ATF3 expression in cardiomyocytes preserves homeostasis in the heart and controls peripheral glucose tolerance
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Tsonwin Hai, Ortal Schwartz, Lilach Koren, Roy Kalfon, Sharon Aviram, and Ami Aronheim
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Blood Glucose ,0301 basic medicine ,Cardiac function curve ,medicine.medical_specialty ,Diabetic Cardiomyopathies ,Physiology ,Cardiac fibrosis ,medicine.medical_treatment ,Cardiomyopathy ,Cardiomegaly ,Inflammation ,Type 2 diabetes ,Fatty Acids, Nonesterified ,030204 cardiovascular system & hematology ,Biology ,Diet, High-Fat ,03 medical and health sciences ,0302 clinical medicine ,Physiology (medical) ,Diabetic cardiomyopathy ,Internal medicine ,medicine ,Animals ,Homeostasis ,Insulin ,Glucose homeostasis ,Genetic Predisposition to Disease ,Myocytes, Cardiac ,Promoter Regions, Genetic ,Cells, Cultured ,Mice, Knockout ,Activating Transcription Factor 3 ,Integrases ,Myosin Heavy Chains ,Ventricular Remodeling ,Interleukin-6 ,Tumor Necrosis Factor-alpha ,medicine.disease ,Fibrosis ,Mice, Inbred C57BL ,Disease Models, Animal ,Phenotype ,030104 developmental biology ,Endocrinology ,Diabetes Mellitus, Type 2 ,Inflammation Mediators ,medicine.symptom ,Cardiology and Cardiovascular Medicine - Abstract
Aims Obesity and type 2 diabetes (T2D) trigger a harmful stress-induced cardiac remodeling process known as cardiomyopathy. These diseases represent a serious and widespread health problem in the Western world; however the underlying molecular basis is not clear. ATF3 is an ‘immediate early’ gene whose expression is highly and transiently induced in response to multiple stressors such as metabolic, oxidative, endoplasmic reticulum and inflammation, stressors that are involved in T2D cardiomyopathy. The role of ATF3 in diabetic cardiomyopathy is currently unknown. Our research has aimed to study the effect of ATF3 expression on cardiomyocytes, heart function and glucose homeostasis in an obesity-induced T2D mouse model. Methods and results We used wild type mice (WT) as well as mutant mice with a cardiac-specific ATF3 deficiency (ATF3-cKO). Mice were fed a high-fat diet (HFD) for 15 weeks. HFD induced high ATF3 expression in cardiomyocytes. Mice were examined for cardiac remodeling processes and the diabetic state was assessed. HFD-fed ATF3-cKO mice exhibited severe cardiac fibrosis, higher levels of heart hypertrophic markers, increased inflammation and worse cardiac function, as compared to WT mice. Interestingly, HFD-fed ATF3-cKO mice display increased hyperglycemia and reduced glucose tolerance, despite higher blood insulin levels, as compared to HFD-fed WT mice. Elevated levels of the cardiac inflammatory cytokines IL-6 and TNFα leading to impaired insulin signalling may partially explain the peripheral glucose intolerance. Conclusions Cardiac ATF3 has a protective role in dampening the HFD-induced cardiac remodeling processes. ATF3 exerts both local and systemic effects related to T2D-induced cardiomyopathy. This study provides a strong relationship between heart remodeling processes and blood glucose homeostasis. more...
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- 2016
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5. p38 MAPK in Glucose Metabolism of Skeletal Muscle: Beneficial or Harmful?
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Sharon Aviram, Tony Hayek, and Eyal Bengal
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0301 basic medicine ,MAPK/ERK pathway ,Glucose uptake ,Review ,Type 2 diabetes ,p38 Mitogen-Activated Protein Kinases ,lcsh:Chemistry ,0302 clinical medicine ,energy metabolism ,Insulin ,Phosphorylation ,lcsh:QH301-705.5 ,Spectroscopy ,exercise ,General Medicine ,Computer Science Applications ,medicine.anatomical_structure ,Carbohydrate Metabolism ,type 2 diabetes ,Signal transduction ,signal transduction ,medicine.medical_specialty ,030209 endocrinology & metabolism ,p38 MAPK ,Carbohydrate metabolism ,Catalysis ,Inorganic Chemistry ,03 medical and health sciences ,Insulin resistance ,Internal medicine ,Glucose Intolerance ,medicine ,Animals ,Humans ,Obesity ,skeletal muscle ,Physical and Theoretical Chemistry ,Muscle, Skeletal ,Molecular Biology ,business.industry ,Organic Chemistry ,Skeletal muscle ,Biological Transport ,medicine.disease ,Glucose ,030104 developmental biology ,Endocrinology ,Diabetes Mellitus, Type 2 ,lcsh:Biology (General) ,lcsh:QD1-999 ,Insulin Resistance ,Metabolic syndrome ,business - Abstract
Skeletal muscles respond to environmental and physiological changes by varying their size, fiber type, and metabolic properties. P38 mitogen-activated protein kinase (MAPK) is one of several signaling pathways that drive the metabolic adaptation of skeletal muscle to exercise. p38 MAPK also participates in the development of pathological traits resulting from excessive caloric intake and obesity that cause metabolic syndrome and type 2 diabetes (T2D). Whereas p38 MAPK increases insulin-independent glucose uptake and oxidative metabolism in muscles during exercise, it contrastingly mediates insulin resistance and glucose intolerance during metabolic syndrome development. This article provides an overview of the apparent contradicting roles of p38 MAPK in the adaptation of skeletal muscles to exercise and to pathological conditions leading to glucose intolerance and T2D. Here, we focus on the involvement of p38 MAPK in glucose metabolism of skeletal muscle, and discuss the possibility of targeting this pathway to prevent the development of T2D. more...
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- 2020
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6. WDR62 mediates TNFα-dependent JNK activation via TRAF2-MLK3 axis
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Ami Aronheim, Sharon Aviram, and Elad Prinz
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0301 basic medicine ,Scaffold protein ,MAPK/ERK pathway ,p38 mitogen-activated protein kinases ,Apoptosis ,Cell Cycle Proteins ,Nerve Tissue Proteins ,MAPK cascade ,Biology ,Models, Biological ,03 medical and health sciences ,0302 clinical medicine ,Cell Line, Tumor ,Humans ,Molecular Biology ,MAP kinase kinase kinase ,Base Sequence ,Kinase ,Tumor Necrosis Factor-alpha ,JNK Mitogen-Activated Protein Kinases ,Signal transducing adaptor protein ,Cell Biology ,Articles ,MAP Kinase Kinase Kinases ,TNF Receptor-Associated Factor 2 ,Signaling ,Cell biology ,Enzyme Activation ,030104 developmental biology ,030220 oncology & carcinogenesis ,Signal transduction ,Protein Binding ,Signal Transduction - Abstract
The mitogen-activated protein kinases (MAPKs) regulate a variety of cellular processes. The three main MAPK cascades are the extracellular signal-regulated kinases (ERK), c-Jun N-terminal kinase (JNK), and p38 kinases. A typical MAPK cascade is composed of MAP3K-MAP2K-MAPK kinases that are held by scaffold proteins. Scaffolds function to assemble the protein tier and contribute to the specificity and efficacy of signal transmission. WD repeat domain 62 (WDR62) is a JNK scaffold protein, interacting with JNK, MKK7, and several MAP3Ks. The loss of WDR62 in human leads to microcephaly and pachygyria. Yet the role of WDR62 in cellular function is not fully studied. We used the CRISPR/Cas9 and short hairpin RNA approaches to establish a human breast cancer cell line MDA-MB-231 with WDR62 loss of function and studied the consequence to JNK signaling. In growing cells, WDR62 is responsible for the basal expression of c-Jun. In stressed cells, WDR62 specifically mediates TNFα−dependent JNK activation through the association with both the adaptor protein, TNF receptor-associated factor 2 (TRAF2), and the MAP3K protein, mixed lineage kinase 3. TNFα-dependent JNK activation is mediated by WDR62 in HCT116 and HeLa cell lines as well. MDA-MB-231 WDR62-knockout cells display increased resistance to TNFα−induced cell death. Collectively, WDR62 coordinates the TNFα receptor signaling pathway to JNK activation through association with multiple kinases and the adaptor protein TRAF2. more...
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- 2018
7. APOL1nephropathy: from gene to mechanisms of kidney injury
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Sharon Aviram, Karl Skorecki, Walter G. Wasser, and Etty Kruzel-Davila
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0301 basic medicine ,Apolipoprotein L1 ,DNA Mutational Analysis ,030232 urology & nephrology ,Nephropathy ,Loss of heterozygosity ,03 medical and health sciences ,0302 clinical medicine ,Focal segmental glomerulosclerosis ,Gene Frequency ,medicine ,Humans ,Genetic Predisposition to Disease ,Allele ,Allele frequency ,Alleles ,Genetics ,Transplantation ,biology ,DNA ,medicine.disease ,Apolipoproteins ,030104 developmental biology ,Genetic epidemiology ,Nephrology ,Mutation ,biology.protein ,Kidney Diseases ,Lipoproteins, HDL ,Kidney disease - Abstract
The contribution of African ancestry to the risk of focal segmental glomerulosclerosis and chronic kidney disease has been partially explained by the recently described chromosome 22q variants in the gene apolipoprotein L1 (APOL1). The APOL1 variants appear at a high allele frequency in populations of West African ancestry as a result of apparent adaptive selection of the heterozygous state. Heterozygosity protects from infection with Trypanosoma brucei rhodesiense. This review will describe the role of the approaches in population genetics for the description of APOL1-associated nephropathies and draw inferences as to the biologic mechanisms from genetic epidemiology findings to date. Modifier loci can influence APOL1 risk for the development of kidney disease. 'Second hits', both viral and non-viral, may explain the discrepancy between the remarkably high odds ratios and the low lifetime risks of kidney disease in two allele carriers of APOL1 risk variants. Therapeutic strategies for APOL1-associated nephropathies will require the prevention and treatment of these 'second hits' and the development of drugs to protect the APOL1 downstream renal injury pathways. more...
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- 2015
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8. The association of the JNK scaffold protein, WDR62, with the mixed lineage kinase 3, MLK3
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Alan J. Whitmarsh, Ami Aronheim, Miriam Hadad, Ilona Darlyuk-Saadon, Ksenya Cohen-Katsenelson, and Sharon Aviram
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MAP kinase kinase kinase ,MLK3 ,Cyclin-dependent kinase 2 ,WDR62 ,Biology ,Mitogen-activated protein kinase kinase ,MAP2K7 ,Cell biology ,Scaffold ,lcsh:Biology (General) ,biology.protein ,ASK1 ,Cyclin-dependent kinase 9 ,c-Raf ,Kinase activity ,lcsh:QH301-705.5 ,c-Jun N-terminal kinase - Abstract
Mitogen-activated protein kinases (MAPKs) form a kinase tier module in which MAPK, MAP2K and MAP3K are held by scaffold proteins. The scaffold proteins serve as a protein platform for selective and spatial kinase activation. The precise mechanism by which the scaffold proteins function has not yet been fully explained. WD40-repeat protein 62, WDR62 is a novel scaffold protein of the c-Jun N-terminal kinase (JNK) pathway. WDR62 is a 1523 a.a. long protein with no significant sequence homology to a known gene. Previously WDR62 was shown to associate with JNK and MKK4/7 in a modular fashion. Here, we show that WDR62 is able to associate with multiple members of the MAP3K of the mixed lineage kinase family and we map WDR62-MLK3 interacting domains. We identify two separable interacting domains within WDR62 and MLK3 proteins that can cross associate. MLK3 association with WDR62 is independent of JNK and MKK4/7 domains and activities. CDC42 activation disrupts WDR62-MLK3 association independent of MLK3 kinase activity. more...
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- 2015
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9. Two ITS forms co-inhabiting a single genet of an isolate of Terfezia boudieri (Ascomycotina), a desert truffle
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Sharon Aviram, Varda Kagan-Zur, and Nurit Roth-Bejerano
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Heterokaryon ,Truffle ,Base Sequence ,Hypha ,biology ,Molecular Sequence Data ,Terfezia boudieri ,Hyphae ,General Medicine ,Cistaceae ,biology.organism_classification ,Polymerase Chain Reaction ,Microbiology ,Terfezia ,Ascomycota ,Botany ,DNA, Intergenic ,Cloning, Molecular ,Desert Climate ,Israel ,DNA, Fungal ,Molecular Biology ,Polymorphism, Restriction Fragment Length ,Mycelium ,Sequence Deletion - Abstract
Two fruit-bodies of Terfezia boudieri Chatin, each exhibiting a mixture of two ITS -RFLP profiles, were found in the Negev desert of Israel. A mycelial culture obtained from glebal out-growth maintained the double profile, as did proliferating cultures established using single hyphae isolated from the original cultures. The main difference between the two ITS variants lies in a 21 bp deletion in the smaller variant. The question whether both variants are contained within a single nucleus or occupy different nuclei sharing the same cytoplasm is discussed. more...
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- 2004
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10. APOL1 risk variants enhance podocyte necrosis through compromising lysosomal membrane permeability
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Pravin C. Singhal, Karl Skorecki, Ashwani Malhotra, Moin A. Saleem, Aakash Jhaveri, Xiqian Lan, Hongxiu Wen, Sharon Aviram, Joanna Mikulak, Peter W. Mathieson, and Kang Cheng
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Necrosis ,Membrane permeability ,Physiology ,4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid ,Permeability ,Podocyte ,Cathepsin L ,chemistry.chemical_compound ,Chloride Channels ,medicine ,Humans ,Genetic Predisposition to Disease ,Cells, Cultured ,biology ,Glomerulosclerosis, Focal Segmental ,Podocytes ,Glomerulosclerosis ,Genetic Variation ,Chloroquine ,Articles ,Chloride channel blocker ,medicine.disease ,Apolipoprotein L1 ,Actins ,Cell biology ,Black or African American ,medicine.anatomical_structure ,Apolipoproteins ,chemistry ,DIDS ,Immunology ,Chloride channel ,biology.protein ,medicine.symptom ,Lipoproteins, HDL ,Lysosomes - Abstract
Development of higher rates of nondiabetic glomerulosclerosis (GS) in African Americans has been attributed to two coding sequence variants (G1 and G2) in the APOL1 gene. To date, the cellular function and the role of APOL1 variants (Vs) in GS are still unknown. In this study, we examined the effects of overexpressing wild-type (G0) and kidney disease risk variants (G1 and G2) of APOL1 in human podocytes using a lentivirus expression system. Interestingly, G0 inflicted podocyte injury only at a higher concentration; however, G1 and G2 promoted moderate podocyte injury at lower and higher concentrations. APOL1Vs expressing podocytes displayed diffuse distribution of both Lucifer yellow dye and cathepsin L as manifestations of enhanced lysosomal membrane permeability (LMP). Chloroquine attenuated the APOL1Vs-induced increase in podocyte injury, consistent with targeting lysosomes. The chloride channel blocker DIDS prevented APOL1Vs- induced injury, indicating a role for chloride influx in osmotic swelling of lysosomes. Direct exposure of noninfected podocytes with conditioned media from G1- and G2-expressing podocytes also induced injury, suggesting a contributory role of the secreted component of G1 and G2 as well. Adverse host factors (AHFs) such as hydrogen peroxide, hypoxia, TNF-α, and puromycin aminonucleoside augmented APOL1- and APOL1Vs-induced podocyte injury, while the effect of human immunodeficiency virus (HIV) on podocyte injury was overwhelming under conditions of APOLVs expression. We conclude that G0 and G1 and G2 APOL1 variants have the potential to induce podocyte injury in a manner which is further augmented by AHFs, with HIV infection being especially prominent. more...
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- 2014
11. Syria civil war: Outcomes of humanitarian neurosurgical care provided to Syrian wounded refugees in Israel
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Barhoum, Masad, primary, Tobias, Samuel, additional, Elron, Moshe, additional, Sharon, Aviram, additional, Heija, Tariq, additional, and Soustiel, Jean F., additional
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- 2015
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12. The ubiquitin ligase Hul5 promotes proteasomal processivity
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Sharon Aviram and Daniel Kornitzer
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Proteasome Endopeptidase Complex ,Saccharomyces cerevisiae Proteins ,Ubiquitin-Protein Ligases ,Mutant ,Molecular Sequence Data ,Orotidine-5'-Phosphate Decarboxylase ,macromolecular substances ,Saccharomyces cerevisiae ,Ubiquitin-conjugating enzyme ,Ubiquitin ,Cyclins ,Amino Acid Sequence ,Molecular Biology ,biology ,Wild type ,Ubiquitination ,Cell Biology ,Processivity ,Articles ,Ubiquitin ligase ,Proteasome ,Biochemistry ,biology.protein ,Biocatalysis ,Unfolded Protein Response ,Target protein - Abstract
The 26S proteasome is a large cytoplasmic protease that degrades polyubiquitinated proteins to short peptides in a processive manner. The proteasome 19S regulatory subcomplex tethers the target protein via its polyubiquitin adduct and unfolds the target polypeptide, which is then threaded into the proteolytic site-containing 20S subcomplex. Hul5 is a 19S subcomplex-associated ubiquitin ligase that elongates ubiquitin chains on proteasome-bound substrates. We isolated hul5 Delta as a mutation with which fusions of an unstable cyclin to stable reporter proteins accumulate as partially processed products. These products appear transiently in the wild type but are strongly stabilized in 19S ATPase mutants and in the hul5 Delta mutant, supporting a role for the ATPase subunits in the unfolding of proteasome substrates before insertion into the catalytic cavity and suggesting a role for Hul5 in the processive degradation of proteins that are stalled on the proteasome. more...
- Published
- 2009
13. Autophosphorylation-induced degradation of the Pho85 cyclin Pcl5 is essential for response to amino acid limitation
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Einav Simon, Fabian Glaser, Daniel Kornitzer, Tsvia Gildor, and Sharon Aviram
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Models, Molecular ,Threonine ,Saccharomyces cerevisiae Proteins ,Protein Conformation ,Recombinant Fusion Proteins ,Cyclin A ,Molecular Sequence Data ,Saccharomyces cerevisiae ,Biology ,Substrate Specificity ,Protein structure ,Cyclin-dependent kinase ,Cyclins ,Animals ,Amino Acid Sequence ,Amino Acids ,Phosphorylation ,Molecular Biology ,Cyclin ,SKP Cullin F-Box Protein Ligases ,Kinase ,Autophosphorylation ,Cell Biology ,Articles ,Cyclin-Dependent Kinases ,Cell biology ,DNA-Binding Proteins ,Basic-Leucine Zipper Transcription Factors ,Biochemistry ,Mutation ,biology.protein ,Sequence Alignment ,Transcription Factors - Abstract
Pho85 cyclins (Pcls), activators of the yeast cyclin-dependent kinase (CDK) Pho85, belong together with the p35 activator of mammalian CDK5 to a distinct structural cyclin class. Different Pcls target Pho85 to distinct substrates. Pcl5 targets Pho85 specifically to Gcn4, a yeast transcription factor involved in the response to amino acid starvation, eventually causing the degradation of Gcn4. Pcl5 is itself highly unstable, an instability that was postulated to be important for regulation of Gcn4 degradation. We used hybrids between different Pcls to circumscribe the substrate recognition function to the core cyclin box domain of Pcl5. Furthermore, the cyclin hybrids revealed that Pcl5 degradation is uniquely dependent on two distinct degradation signals: one N-terminal and one C-terminal to the cyclin box domain. Whereas the C-terminal degradation signal is independent of Pho85, the N-terminal degradation signal requires phosphorylation of a specific threonine residue by the Pho85 molecule bound to the cyclin. This latter mode of degradation depends on the SCF ubiquitin ligase. Degradation of Pcl5 after self-catalyzed phosphorylation ensures that activity of the Pho85/ Pcl5 complex is self-limiting in vivo. We demonstrate the importance of this mechanism for the regulation of Gcn4 degradation and for cell growth under conditions of amino acid starvation. more...
- Published
- 2008
14. Phylogenetic studies of Terfezia pfeilii and Choiromyces echinulatus (Pezizales) support new genera for southern African truffles: Kalaharituber and Eremiomyces
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Varda Kagan-Zur, James M. Trappe, Yael Ferdman, Nurit Roth-Bejerano, and Sharon Aviram
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Molecular Sequence Data ,Zoology ,Plant Science ,South Africa ,Ascomycota ,Species Specificity ,Genus ,Choiromyces ,Botany ,DNA, Ribosomal Spacer ,RNA, Ribosomal, 28S ,Genetics ,DNA, Fungal ,Pezizales ,Ecology, Evolution, Behavior and Systematics ,Phylogeny ,biology ,Kalaharituber ,Sequence Analysis, DNA ,Tuberaceae ,biology.organism_classification ,RNA, Ribosomal, 5.8S ,Terfezia ,Pezizaceae ,Molecular phylogenetics ,Biotechnology - Abstract
The ITS region including the 5.8S rRNA gene as well as the 5′ end of the 28S rRNA gene of hypogeous Pezizaceae and Tuberaceae were studied to clarify the generic placement of two southern African desert truffles, Terfezia pfeilii and Choiromyces echinulatus. The results show that neither species belongs in the genus to which it has been assigned on the basis of morphological characters. As expected, two Choiromyces spp. grouped close to the representative of the Tuberaceae (Tuber melanosporum). However, C. echinulatus diverged from the other Choiromyces species and emerged near members of the genus Terfezia, being even closer to that genus than T. pfeilii. Two new genera and new species combinations, Kalaharituber gen. nov. with K. pfeilii (syn. T. pfeilii) comb. nov. and Eremiomyces gen. nov. with E. echinulatus (syn. C. echinulatus) comb. nov. are therefore introduced to accomodate these taxa. Both genera are closely related to Terfezia, and thus are placed in the Pezizaceae. more...
- Published
- 2005
15. Phylogenetic Studies of Terfezia pfeilii and Choiromyces echinulatus (Pezizales) support new genera for southern African truffles: Kalaharituber and Eremiomyces.
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Yael FERDMAN, Sharon AVIRAM, Nurit ROTH-BEJERANO, James M. TRAPPE, and Varda KAGAN-ZUR
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TRUFFLES , *PARASITIC plants , *RNA , *NUCLEIC acids , *SPECIES , *MORPHOLOGY , *GENETICS - Abstract
The ITS region including the 5.8S rRNA gene as well as the 5' end of the 28S rRNA gene of hypogeous Pezizaceae and Tuberaceae were studied to clarify the generic placement of two southern African desert truffles, Terfezia pfeilii and Choiromyces echinulatus. The results show that neither species belongs in the genus to which it has been assigned on the basis of morphological characters. As expected, two Choiromyces spp. grouped close to the representative of the Tuberaceae (Tuber melanosporum). However, C. echinulatus diverged from the other Choiromyces species and emerged near members of the genus Terfezia, being even closer to that genus than T. pfeilii. Two new genera and new species combinations, Kalaharituber gen. nov. with K. pfeilii (syn. T. pfeilii) comb. nov. and Eremiomyces gen. nov. with E. echinulatus (syn. C. echinulatus) comb. nov. are therefore introduced to accomodate these taxa. Both genera are closely related to Terfezia, and thus are placed in the Pezizaceae. [ABSTRACT FROM AUTHOR] more...
- Published
- 2005
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