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Maturity-Onset Diabetes of the Young (MODY): Genetic Causes, Clinical Characteristics, Considerations for Testing, and Treatment Options. ENDOCRINES 2021. [DOI: 10.3390/endocrines2040043] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Maturity Onset Diabetes of the Young (MODY) encompasses a group of rare monogenic forms of diabetes distinct in etiology and clinical presentation from the more common forms of Type 1 (autoimmune) and Type 2 diabetes. Since its initial description as a clinical entity nearly 50 years ago, the underlying genetic basis for the various forms of MODY has been increasingly better elucidated. Clinically, the diagnosis may be made in childhood or young adulthood and can present as overt hyperglycemia requiring insulin therapy or as a subtle form of slowly progressive glucose impairment. Due to the heterogeneity of clinical symptoms, patients with MODY may be misdiagnosed as possessing another form of diabetes, resulting in potentially inappropriate treatment and delays in screening of affected family members and associated comorbidities. In this review, we highlight the various known genetic mutations associated with MODY, clinical presentation, indications for testing, and the treatment options available.
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Tsigelny IF, Kouznetsova VL, Lian N, Kesari S. Molecular mechanisms of OLIG2 transcription factor in brain cancer. Oncotarget 2016; 7:53074-53101. [PMID: 27447975 PMCID: PMC5288170 DOI: 10.18632/oncotarget.10628] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 06/03/2016] [Indexed: 12/13/2022] Open
Abstract
Oligodendrocyte lineage transcription factor 2 (OLIG2) plays a pivotal role in glioma development. Here we conducted a comprehensive study of the critical gene regulatory networks involving OLIG2. These include the networks responsible for OLIG2 expression, its translocation to nucleus, cell cycle, epigenetic regulation, and Rho-pathway interactions. We described positive feedback loops including OLIG2: loops of epigenetic regulation and loops involving receptor tyrosine kinases. These loops may be responsible for the prolonged oncogenic activity of OLIG2. The proposed schemes for epigenetic regulation of the gene networks involving OLIG2 are confirmed by patient survival (Kaplan-Meier) curves based on the cancer genome atlas (TCGA) datasets. Finally, we elucidate the Coherent-Gene Modules (CGMs) networks-framework of OLIG2 involvement in cancer. We showed that genes interacting with OLIG2 formed eight CGMs having a set of intermodular connections. We showed also that among the genes involved in these modules the most connected hub is EGFR, then, on lower level, HSP90 and CALM1, followed by three lower levels including epigenetic genes KDM1A and NCOR1. The genes on the six upper levels of the hierarchy are involved in interconnections of all eight CGMs and organize functionally defined gene-signaling subnetworks having specific functions. For example, CGM1 is involved in epigenetic control. CGM2 is significantly related to cell proliferation and differentiation. CGM3 includes a number of interconnected helix-loop-helix transcription factors (bHLH) including OLIG2. Many of these TFs are partially controlled by OLIG2. The CGM4 is involved in PDGF-related: angiogenesis, tumor cell proliferation and differentiation. These analyses provide testable hypotheses and approaches to inhibit OLIG2 pathway and relevant feed-forward and feedback loops to be interrogated. This broad approach can be applied to other TFs.
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Affiliation(s)
- Igor F. Tsigelny
- Department of Neurosciences, University of California San Diego, La Jolla, 92093-0752, CA, USA
- San Diego Supercomputer Center, University of California San Diego, La Jolla, 92093-0505, CA, USA
- Moores Cancer Center, University of California San Diego, La Jolla, 92093, CA, USA
| | - Valentina L. Kouznetsova
- San Diego Supercomputer Center, University of California San Diego, La Jolla, 92093-0505, CA, USA
- Moores Cancer Center, University of California San Diego, La Jolla, 92093, CA, USA
| | - Nathan Lian
- REHS, San Diego Supercomputer Center, University of California San Diego, La Jolla, 92093-0505, CA, USA
| | - Santosh Kesari
- John Wayne Cancer Institute at Providence Saint John's Health Center, Santa Monica, 90404, CA, USA
- Pacific Neuroscience Institute at Providence Saint John's Health Center, Santa Monica, 90404, CA, USA
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Szopa M, Ludwig-Galezowska AH, Radkowski P, Skupien J, Machlowska J, Klupa T, Wolkow P, Borowiec M, Mlynarski W, Malecki MT. A family with the Arg103Pro mutation in the NEUROD1 gene detected by next-generation sequencing – Clinical characteristics of mutation carriers. Eur J Med Genet 2016; 59:75-9. [DOI: 10.1016/j.ejmg.2016.01.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Revised: 11/25/2015] [Accepted: 01/06/2016] [Indexed: 12/31/2022]
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Flannick J, Beer NL, Bick AG, Agarwala V, Molnes J, Gupta N, Burtt NP, Florez JC, Meigs JB, Taylor H, Lyssenko V, Irgens H, Fox E, Burslem F, Johansson S, Brosnan MJ, Trimmer JK, Newton-Cheh C, Tuomi T, Molven A, Wilson JG, O'Donnell CJ, Kathiresan S, Hirschhorn JN, Njølstad PR, Rolph T, Seidman J, Gabriel S, Cox DR, Seidman C, Groop L, Altshuler D. Assessing the phenotypic effects in the general population of rare variants in genes for a dominant Mendelian form of diabetes. Nat Genet 2013; 45:1380-5. [PMID: 24097065 PMCID: PMC4051627 DOI: 10.1038/ng.2794] [Citation(s) in RCA: 105] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2013] [Accepted: 09/13/2013] [Indexed: 12/25/2022]
Abstract
Genome sequencing can identify individuals in the general population who harbor rare coding variants in genes for Mendelian disorders and who may consequently have increased disease risk. Previous studies of rare variants in phenotypically extreme individuals display ascertainment bias and may demonstrate inflated effect-size estimates. We sequenced seven genes for maturity-onset diabetes of the young (MODY) in well-phenotyped population samples (n = 4,003). We filtered rare variants according to two prediction criteria for disease-causing mutations: reported previously in MODY or satisfying stringent de novo thresholds (rare, conserved and protein damaging). Approximately 1.5% and 0.5% of randomly selected individuals from the Framingham and Jackson Heart Studies, respectively, carry variants from these two classes. However, the vast majority of carriers remain euglycemic through middle age. Accurate estimates of variant effect sizes from population-based sequencing are needed to avoid falsely predicting a substantial fraction of individuals as being at risk for MODY or other Mendelian diseases.
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Affiliation(s)
- Jason Flannick
- Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, MA, USA
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA, USA
- Diabetes Unit, Massachusetts General Hospital, Boston, MA, USA
| | - Nicola L Beer
- Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, MA, USA
| | - Alexander G Bick
- Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, MA, USA
- Department of Genetics, Harvard Medical School, Boston, MA, USA
| | - Vineeta Agarwala
- Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, MA, USA
- Harvard-MIT Division of Health Sciences and Technology, MIT, Cambridge, MA, USA
- Program in Biophysics, Graduate School of Arts and Sciences, Harvard University, Cambridge, MA, USA
| | - Janne Molnes
- KG Jebsen Center for Diabetes Research, Department of Clinical Science, University of Bergen, Bergen, Norway
| | - Namrata Gupta
- Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, MA, USA
| | - Noel P Burtt
- Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, MA, USA
| | - Jose C Florez
- Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, MA, USA
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA, USA
- Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - James B Meigs
- Department of Medicine, Harvard Medical School, Boston, MA, USA
- General Medicine Division, Massachusetts General Hospital, Boston, MA, USA
| | - Herman Taylor
- Department of Medicine, University of Mississippi Medical Center, Jackson, MS, USA
- Jackson State University, Jackson, MS, USA
- Tougaloo College, Tougaloo MS, USA
| | - Valeriya Lyssenko
- Department of Clinical Sciences, Diabetes and Endocrinology, Clinical Research Centre, Lund University, Malmö, Sweden
| | - Henrik Irgens
- KG Jebsen Center for Diabetes Research, Department of Clinical Science, University of Bergen, Bergen, Norway
- Department of Pediatrics, Haukeland University Hospital, Bergen, Norway
| | - Ervin Fox
- Department of Medicine, University of Mississippi Medical Center, Jackson, MS, USA
| | - Frank Burslem
- Cardiovascular and Metabolic Diseases Practice, Prescient Life Sciences, London, UK
| | - Stefan Johansson
- KG Jebsen Center for Diabetes Research, Department of Clinical Science, University of Bergen, Bergen, Norway
- Center for Medical Genetics and Molecular Medicine, Haukeland University Hospital, Bergen, Norway
| | - M Julia Brosnan
- Cardiovascular and Metabolic Diseases Research Unit, Pfizer Inc., Cambridge, MA, USA
| | - Jeff K Trimmer
- Cardiovascular and Metabolic Diseases Research Unit, Pfizer Inc., Cambridge, MA, USA
| | - Christopher Newton-Cheh
- Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, MA, USA
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA, USA
- National Heart, Lung, and Blood Institute's Framingham Heart Study, Framingham, MA, USA
- Cardiology Division, Massachusetts General Hospital, Boston, MA, USA
| | - Tiinamaija Tuomi
- Department of General Practice and Primary Health Care, University of Helsinki, Helsinki, Finland
- Department of Medicine, Helsinki University Central Hospital and Research Program for Molecular Medicine
| | - Anders Molven
- KG Jebsen Center for Diabetes Research, Department of Clinical Science, University of Bergen, Bergen, Norway
- Gade Laboratory for Pathology, Department of Clinical Medicine, University of Bergen, Bergen, Norway
- Department of Pathology, Haukeland University Hospital, Bergen, Norway
| | - James G Wilson
- Department of Physiology and Biophysics, University of Mississippi Medical Center, Jackson, MS, USA
| | - Christopher J O'Donnell
- National Heart, Lung, and Blood Institute's Framingham Heart Study, Framingham, MA, USA
- Cardiology Division, Massachusetts General Hospital, Boston, MA, USA
- Division of Intramural Research, National Heart, Lung, and Blood Institute, Bethesda, MD, USA
| | - Sekar Kathiresan
- Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, MA, USA
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA, USA
- Cardiology Division, Massachusetts General Hospital, Boston, MA, USA
| | - Joel N Hirschhorn
- Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, MA, USA
- Department of Genetics, Harvard Medical School, Boston, MA, USA
- Divisions of Genetics and Endocrinology and Program in Genomics, Children's Hospital, Boston, MA, USA
| | - Pål R Njølstad
- Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, MA, USA
- KG Jebsen Center for Diabetes Research, Department of Clinical Science, University of Bergen, Bergen, Norway
- Department of Pediatrics, Haukeland University Hospital, Bergen, Norway
| | - Tim Rolph
- Cardiovascular and Metabolic Diseases Research Unit, Pfizer Inc., Cambridge, MA, USA
| | - J.G. Seidman
- Department of Genetics, Harvard Medical School, Boston, MA, USA
| | - Stacey Gabriel
- Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, MA, USA
| | - David R Cox
- Applied Quantitative Genotherapeutics, Pfizer Inc., South San Francisco, CA, USA
| | - Christine Seidman
- Department of Genetics, Harvard Medical School, Boston, MA, USA
- Division of Cardiovascular Medicine, Brigham and Women’s Hospital, Boston, MA, USA
- Howard Hughes Medical Institute, Chevy Chase, MD, USA
| | - Leif Groop
- Department of Clinical Sciences, Diabetes and Endocrinology, Clinical Research Centre, Lund University, Malmö, Sweden
- Finnish Institute for Molecular Medicine (FIMM), Helsinki University, Helsinki, Finland
| | - David Altshuler
- Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, MA, USA
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA, USA
- Department of Genetics, Harvard Medical School, Boston, MA, USA
- Department of Medicine, Harvard Medical School, Boston, MA, USA
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Gong ZC, Huang Q, Dai XP, Lei GH, Lu HB, Yin JY, Xu XJ, Qu J, Pei Q, Dong M, Zhou BT, Shen J, Zhou G, Zhou HH, Liu ZQ. NeuroD1 A45T and PAX4 R121W polymorphisms are associated with plasma glucose level of repaglinide monotherapy in Chinese patients with type 2 diabetes. Br J Clin Pharmacol 2013; 74:501-9. [PMID: 22296034 DOI: 10.1111/j.1365-2125.2012.04202.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
AIMS We aimed to determine whether NeuroD1/BETA2 and PAX4 polymorphisms were associated with the therapeutic efficacy of repaglinide in Chinese type 2 diabetes mellitus (T2DM) patients. METHODS Three hundred and sixty-eight T2DM patients and 132 healthy control subjects were genotyped by restriction fragment length polymorphism. Forty-three patients with various genotypes were randomly selected to undergo 8 weeks of repaglinide treatment (3 mg day(-1)). Fasting plasma glucose, postprandial plasma glucose, glycated haemoglobin, fasting and postprandial serum insulin (FINS, PINS), homeostasis model assessment for insulin resistance, serum triglyceride, total cholesterol, low-density lipoprotein-cholesterol and high-density lipoprotein-cholesterol were determined before and after repaglinide treatment. RESULTS The allelic frequency of NeuroD1/BETA2 T45 was higher in T2DM patients than in the control subjects [13.45 vs. 6.82%, P < 0.01, odds ratios = 2.342 (1.365, 4.019), P= 0.002]. Type 2 diabetes mellitus patients with the mutated allele of NeuroD1/BETA2 A45T polymorphism showed higher FINS (13.46 ± 12.57 vs. 10.04 ± 7.09 mU l(-1) , P < 0.05) (11.67, 14.83 vs. 8.38, 11.37) and PINS (52.11 ± 40.93 vs. 68.66 ± 43.87 mU l(-1), P < 0.05) (44.89, 58.35 vs. 55.35, 88.87) than individuals with the T allele. The PAX4 R121W R allele carriers had higher PINS (52.11 ± 40.93 vs. 68.66 ± 43.87 mU l(-1), P < 0.05) (44.89, 58.35 vs. 55.35, 88.87) than subjects with the W allele. After repaglinide treatment, patients with the T allele of NeuroD1/BETA2 A45T polymorphisms had attenuated efficacy on fasting plasma glucose (-2.79 ± 2.14 vs.-0.99 ± 1.80 mmol l(-1), P < 0.01) (-3.53, -1.84 vs.-1.99, -0.13) and postprandial plasma glucose (-6.71 ± 5.90 vs.-2.54 ± 3.39 mmol l(-1), P < 0.01) (-9.28, -4.62 vs.-4.34, -0.84). Patients with the RR genotype of PAX4 R121W showed better efficacy with respect to the level of postprandial plasma glucose than R/W genotypes (-6.53 ± 6.52 vs.-2.95 ± 1.17 mmol l(-1), P < 0.05) (-8.20, -4.89 vs.-3.92, -1.20). CONCLUSIONS The NeuroD1/BETA2 and PAX4 polymorphisms were substantially associated with plasma glucose level after repaglinide monotherapy.
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Affiliation(s)
- Zhi-Cheng Gong
- Institute of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics, Central South University, Changsha, Hunan, China
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Immunohistological markers for proliferative events, gliogenesis, and neurogenesis within the adult hippocampus. Cell Tissue Res 2011; 345:1-19. [PMID: 21647561 DOI: 10.1007/s00441-011-1196-4] [Citation(s) in RCA: 237] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2011] [Accepted: 05/13/2011] [Indexed: 12/29/2022]
Abstract
Biologists long believed that, once development is completed, no new neurons are produced in the forebrain. However, as is now firmly established, new neurons can be produced at least in two specific forebrain areas: the subventricular zone (SVZ) and the dentate gyrus (DG) of the hippocampal formation. Neurogenesis within the adult DG occurs constitutively throughout postnatal life, and the rate of neurogenesis within the DG can be altered under various physiological and pathophysiological conditions. The process of adult neurogenesis within the DG is a multi-step process (proliferation, differentiation, migration, targeting, and synaptic integration) that ends with the formation of a post-mitotic functionally integrated new neuron. Various markers are expressed during specific stages of adult neurogenesis. The availability of such markers allows the time-course and fate of newly born cells to be followed within the DG in a detailed and precise fashion. Several of the available markers (e.g., PCNA, Ki-67, PH3, MCM2) are markers for proliferative events, whereas others are more specific for early phases of neurogenesis and gliogenesis within the adult DG (e.g., nestin, GFAP, Sox2, Pax6). In addition, markers are available allowing events to be distinguished that are related to later steps of gliogenesis (e.g., vimentin, BLBP, S100beta) or neurogenesis (e.g., NeuroD, PSA-NCAM, DCX).
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Li Y, Peng Z, Xiao B, Houser CR. Activation of ERK by spontaneous seizures in neural progenitors of the dentate gyrus in a mouse model of epilepsy. Exp Neurol 2010; 224:133-45. [PMID: 20226181 DOI: 10.1016/j.expneurol.2010.03.003] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2009] [Revised: 01/19/2010] [Accepted: 03/02/2010] [Indexed: 11/18/2022]
Abstract
Cellular changes that are associated with spontaneous seizures in temporal lobe epilepsy are not well understood but could influence ongoing epilepsy-related processes. In order to identify cell signaling events that could occur at the time of spontaneous seizures, the localization of phosphorylated extracellular signal-regulated kinase (pERK) was studied in a pilocarpine mouse model of epilepsy at very short intervals (1.5-2.5 min) after detection of a spontaneous seizure. Within the hippocampal formation, immunolabeling of pERK was evident in a subpopulation of cells in the subgranular zone (SGZ) of the dentate gyrus at these short intervals. Many of these cells had a long vertical process and resembled radial glia, while others had short processes and were oriented horizontally. Labeling with a series of developmental markers demonstrated that virtually all pERK-labeled cells were neural progenitor cells (NPCs). A high percentage ( approximately 80%) of the pERK-labeled cells was labeled with either glial fibrillary acidic protein or brain lipid binding protein, indicating that these cells were radial glia-like NPCs. A smaller percentage of labeled cells expressed NeuroD, suggesting that they were later-developing NPCs that were assuming a neuronal identity. Early expression of pERK was not detected in immature neurons. Double labeling with proliferation markers demonstrated that approximately 30% of pERK-labeled NPCs expressed Mcm2, indicating that they were actively proliferating. Furthermore, virtually all radial glia-like NPCs that were in the proliferative cycle expressed pERK. These findings suggest that spontaneous seizures and associated ERK activation could contribute to the proliferation of radial glia-like NPCs in this epilepsy model.
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Affiliation(s)
- Yi Li
- Department of Neurobiology, CHS 73-235, David Geffen School of Medicine at the University of California, Los Angeles, Los Angeles, CA 90095-1763, USA
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Gonsorcíková L, Průhová S, Cinek O, Ek J, Pelikánová T, Jørgensen T, Eiberg H, Pedersen O, Hansen T, Lebl J. Autosomal inheritance of diabetes in two families characterized by obesity and a novel H241Q mutation in NEUROD1. Pediatr Diabetes 2008; 9:367-72. [PMID: 18331410 DOI: 10.1111/j.1399-5448.2008.00379.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND The aim of the study was to search for mutations in the NEUROD1 and IPF-1 genes in patients with clinical characteristics of maturity-onset diabetes of the young (MODY) but with no mutations in the HNF-4A (MODY1), GCK (MODY2) and TCF1 (MODY3) genes. METHODS We studied 30 unrelated Czech probands with a clinical diagnosis of MODY (median age at testing, 18 yr; median age at the recognition of hyperglycaemia, 16 yr). The promoter, exons and exon/intron boundaries of the NEUROD1 and IPF-1 genes were examined by polymerase chain reaction-denaturing high performance liquid chromatography and direct sequencing. RESULTS While no mutations were found in the IPF-1 gene, a novel H241Q substitution of NEUROD1 gene was identified in two unrelated families. In the first proband, the H241Q mutation led to early diagnosed (20 yr) hyperglycaemia followed by development of diabetic microvascular complications by the age of 32 yr. The second proband suffered from slowly progressing hyperglycaemia detected at the age of 30 yr. Affected members of both families were obese. The overall prevalence of the variant among the general population was 4 of 13 568 chromosomes. CONCLUSIONS We report a novel disease-associated variant in NEUROD1 identified among a set of MODYX families. The variant seems to precipitate type-2-like diabetes in excessively obese individuals.
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Affiliation(s)
- Lucie Gonsorcíková
- Department of Paediatrics, Second Faculty of Medicine, Charles University in Prague, Prague, Czech Republic
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von Bohlen Und Halbach O. Immunohistological markers for staging neurogenesis in adult hippocampus. Cell Tissue Res 2007; 329:409-20. [PMID: 17541643 DOI: 10.1007/s00441-007-0432-4] [Citation(s) in RCA: 318] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2007] [Accepted: 04/25/2007] [Indexed: 12/11/2022]
Abstract
Neurogenesis in the adult dentate gyrus (DG) of the hippocampus occurs constitutively throughout postnatal life, and the rate of neurogenesis within the DG can be altered under various physiological and pathophysiological conditions. Adult neurogenesis includes the process in which the division of a precursor cell takes place and the multi-step process (proliferation, differentiation, migration, targeting, and synaptic integration) that ends with the formation of a postmitotic functionally integrated new neuron. During specific time-frames of adult neurogenesis, various markers are expressed that correlate with the differentiation steps along the pathway from early progenitor cells to newly generated postmitotic neurons within the DG. Markers that are currently widely used for the investigation of adult hippocampal neurogenesis are: glial fibrillary acidic protein, nestin, Pax6, NeuroD, PSA-NCAM, doublecortin, TUC-4, Tuj-1, and calretinin. The discovery and development of specific markers that allow the time-course and fate of neurons to be followed during adult neurogenesis in a detailed and precise fashion are not only helpful for gaining further insights into the genesis of new neurons in the hippocampus, but also might be applicable to the development of strategies for therapeutic interventions.
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Affiliation(s)
- O von Bohlen Und Halbach
- Interdisciplinary Center for Neurosciences, Department of Neuroanatomy, University of Heidelberg, Im Neuenheimer Feld 307, 69120 Heidelberg, Germany.
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Liu L, Furuta H, Minami A, Zheng T, Jia W, Nanjo K, Xiang K. A novel mutation, Ser159Pro in the NeuroD1/BETA2 gene contributes to the development of diabetes in a Chinese potential MODY family. Mol Cell Biochem 2007; 303:115-20. [PMID: 17440689 DOI: 10.1007/s11010-007-9463-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2007] [Accepted: 03/21/2007] [Indexed: 10/23/2022]
Abstract
OBJECTIVES During examining the prevalence of mutations in NeuroD1/BETA2 gene in Chinese early-onset type 2 diabetic probands, a novel missense mutation, Ser159Pro in a potential MODY family was identified. To investigate the role of the mutation in early-onset diabetes, we studied its transcriptional activity on human insulin gene and clinical characteristics of the family with the mutation. METHODS Bi-directional sequencing of NeuroD1/BETA2 was performed in 85 early-onset type 2 diabetic probands without mutations in HNF4alpha, glucokinase, HNF1alpha, IPF-1 and HNF1beta genes, 95 late-onset type 2 diabetics with strong diabetic history and 87 non-diabetic control subjects. The function of the Ser159Pro to the transcription of a human insulin promotor-linked luciferase reporter gene in rat INS-1 cells was tested using Dual-Luciferase Reporter Assay System. Clinical phenotypes of the family with the Ser159Pro mutation were examined and analyzed. RESULTS A novel mutation, Ser159Pro were found in a 27-years-old proband with both parents had diabetes. The mutation was transmitted in the heterozygous state and co-segregated with diabetes in four out of five carriers from the paternal side. Expect for the proband, all of other members with this mutation in the family, however, were diagnosed with diabetes after 50-years-old. The functional study showed that the mutant protein exhibited a 25% reduction in transcriptional activity of insulin gene when compared with the wild type. CONCLUSIONS These results suggest that the novel Ser159Pro mutation in the NeuroD1/BETA2 gene contributes to the development of diabetes in a Chinese potential MODY family.
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Affiliation(s)
- Limei Liu
- Department of Endocrinology & Metabolism, Shanghai Jiaotong University Affiliated Sixth People's Hospital, Shanghai Diabetes Institute, Shanghai, China.
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Hiroshima K, Iyoda A, Shida T, Shibuya K, Iizasa T, Kishi H, Tanizawa T, Fujisawa T, Nakatani Y. Distinction of pulmonary large cell neuroendocrine carcinoma from small cell lung carcinoma: a morphological, immunohistochemical, and molecular analysis. Mod Pathol 2006; 19:1358-68. [PMID: 16862075 DOI: 10.1038/modpathol.3800659] [Citation(s) in RCA: 108] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The distinction between pulmonary large cell neuroendocrine carcinoma and small cell carcinoma is difficult in some cases. Some propose that these carcinomas should be classified as one high-grade neuroendocrine carcinoma. We examined biological features of small cell carcinoma (n=23), large cell neuroendocrine carcinoma (n=17), and classic large cell carcinoma (n=12). The average ratio of nuclear diameter of the tumor cells to that of lymphocytes for small cell carcinoma was smaller than that for large cell neuroendocrine carcinoma (P<0.0001). The frequencies of the expressions of CD56, mASH1, TTF-1, and p16 were higher and that of NeuroD was lower in small cell carcinoma than in large cell neuroendocrine carcinoma. The frequency of loss of heterozygosity at 3p was higher in high-grade neuroendocrine carcinomas than in classic large cell carcinoma (P=0.0002). Allelic losses at D5S422 (5q33) were more frequent in small cell carcinoma than in large cell neuroendocrine carcinoma (P=0.0091). Mean fractional regional loss indices of the tumors were 0.38, 0.65, and 0.72 for patients with classic large cell carcinoma, large cell neuroendocrine carcinoma, and small cell carcinoma, respectively (P=0.0003). Five-year overall survivals of patients with classic large cell carcinoma, large cell neuroendocrine carcinoma and small cell carcinoma in stage I were 67, 73, 60%, respectively. Patients with NeuroD expression had better survivals, and those with p63 expression had poorer survivals in large cell neuroendocrine carcinoma. Patients with TTF-1 expression had poorer survivals in small cell carcinoma. Our data suggest that large cell neuroendocrine carcinoma and small cell carcinoma are different morphologically, phenotypically, and genetically, although there are some overlapping features. Although further studies are needed to analyze the biological behavior of high-grade neuroendocrine carcinomas including sensitivity to chemotherapy, the pathological distinction of large cell neuroendocrine carcinoma from small cell carcinoma may be necessary to treat the patients with neuroendocrine tumors.
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MESH Headings
- Basic Helix-Loop-Helix Transcription Factors/analysis
- Carcinoma, Large Cell/chemistry
- Carcinoma, Large Cell/genetics
- Carcinoma, Large Cell/pathology
- Carcinoma, Neuroendocrine/chemistry
- Carcinoma, Neuroendocrine/genetics
- Carcinoma, Neuroendocrine/pathology
- Carcinoma, Small Cell/chemistry
- Carcinoma, Small Cell/genetics
- Carcinoma, Small Cell/pathology
- Cell Size
- DNA Methylation
- DNA-Binding Proteins/analysis
- Diagnosis, Differential
- Genes, p16
- Humans
- Immunohistochemistry
- Loss of Heterozygosity
- Lung Neoplasms/chemistry
- Lung Neoplasms/genetics
- Lung Neoplasms/pathology
- Microsatellite Repeats/genetics
- Polymerase Chain Reaction
- Prognosis
- Retrospective Studies
- Survival Analysis
- Transcription Factors
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Affiliation(s)
- Kenzo Hiroshima
- Department of Diagnostic Pathology, Graduate School of Medicine, Chiba University, Chiba, Japan.
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12
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Cinek O, Drevínek P, Sumník Z, Bendlová B, Sedláková P, Kolousková S, Snajderová M, Vavrinec J. NEUROD polymorphism Ala45Thr is associated with Type 1 diabetes mellitus in Czech children. Diabetes Res Clin Pract 2003; 60:49-56. [PMID: 12639765 DOI: 10.1016/s0168-8227(02)00251-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Association of the NEUROD Ala45Thr polymorphism with Type 1 diabetes mellitus (DM) has been found in some but not all populations. We performed a study on the association of two NEUROD exon 2 polymorphisms, the Ala45Thr and the Pro197His, with childhood-onset Type 1 DM in the Czech population. We compared 285 children with Type 1 DM diagnosed under the age of 15 years with 289 non-diabetic control children. The genotypes were determined using novel real-time allele-specific PCR assays in the TaqMan format, and data were analysed using logistic regression. The numbers of subjects with codon 45 genotypes Ala/Ala, Ala/Thr, Thr/Thr were 95, 145, 45 among cases and 117, 130, 42 among controls. Thr45 phenotypic positivity was associated with a significant risk of Type 1 DM (OR=2.01, CI 95% 1.25-3.24) in a multivariate logistic regression model involving also the insulin gene -23HphI genotype and the presence of Type 1 DM-associated HLA-DQB1*0302-DQA1*03 (DQ8) and DQB1*0201-DQA1*05 (DQ2) molecules. No association was observed for the Pro197His mutation which was carried by 5.3% cases and 5.9% controls. Our results confirm that the NEUROD Ala45Thr polymorphism is associated with childhood-onset Type 1 DM.
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Affiliation(s)
- Ondrej Cinek
- Second Department of Paediatrics, Second Faculty of Medicine, Charles University, V Uvalu 84, Prague 5 CZ-150 06, Czech Republic.
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13
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Rosmalen JGM, Leenen PJM, Pelegri C, Drexhage HA, Homo-Delarche F. Islet abnormalities in the pathogenesis of autoimmune diabetes. Trends Endocrinol Metab 2002; 13:209-14. [PMID: 12185667 DOI: 10.1016/s1043-2760(02)00600-8] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Type 1 diabetes mellitus is a T-cell-mediated autoimmune disease that results in the destruction of the insulin-producing beta cells in the pancreatic islets of Langerhans. In spite of extensive genetic and immunological studies, mainly performed in the non-obese diabetic (NOD) spontaneous mouse model, the etiology of the autoimmune attack remains unknown. Several autoantigens have been identified and numerous studies have suggested a role for defective regulation of immune function. However, this account does not explain why the autoimmune process specifically affects the insulin-producing beta cells. Thus, abnormal immune regulation might explain the predisposition to autoimmunity in general, but additional factors should then determine the target of the autoimmune attack. Here, we review the evidence that abnormalities in islet cell differentiation and function exist that might trigger the immune system towards beta-cell autoimmunity in humans and NOD mice.
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Affiliation(s)
- Judith G M Rosmalen
- Dept Immunology, Erasmus MC, University Medical Center, PO Box 1738, 3000 DR Rotterdam, The Netherlands
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14
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Sierra DA, Gilbert DJ, Householder D, Grishin NV, Yu K, Ukidwe P, Barker SA, He W, Wensel TG, Otero G, Brown G, Copeland NG, Jenkins NA, Wilkie TM. Evolution of the regulators of G-protein signaling multigene family in mouse and human. Genomics 2002; 79:177-85. [PMID: 11829488 DOI: 10.1006/geno.2002.6693] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The regulators of G-protein signaling (RGS) proteins are important regulatory and structural components of G-protein coupled receptor complexes. RGS proteins are GTPase activating proteins (GAPs) of Gi-and Gq-class Galpha proteins, and thereby accelerate signaling kinetics and termination. Here, we mapped the chromosomal positions of all 21 Rgs genes in mouse, and determined human RGS gene structures using genomic sequence from partially assembled bacterial artificial chromosomes (BACs) and Celera fragments. In mice and humans, 18 of 21 RGS genes are either tandemly duplicated or tightly linked to genes encoding other components of G-protein signaling pathways, including Galpha, Ggamma, receptors (GPCR), and receptor kinases (GPRK). A phylogenetic tree revealed seven RGS gene subfamilies in the yeast and metazoan genomes that have been sequenced. We propose that similar systematic analyses of all multigene families from human and other mammalian genomes will help complete the assembly and annotation of the human genome sequence.
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Affiliation(s)
- David A Sierra
- Pharmacology Department, UT Southwestern, Dallas, Texas 75390-9041, USA
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15
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Mochizuki M, Amemiya S, Kobayashi K, Kobayashi K, Ishihara T, Aya M, Kato K, Kasuga A, Nakazawa S. The association of Ala45Thr polymorphism in NeuroD with child-onset Type 1a diabetes in Japanese. Diabetes Res Clin Pract 2002; 55:11-7. [PMID: 11755474 DOI: 10.1016/s0168-8227(01)00242-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Recently Iwata et al. reported that the polymorphism in NeuroD exon 2(Ala45Thr) was associated with adult-onset Type 1 diabetes in Japanese. Furthermore, the mutations in the NeuroD as a regulator of insulin transcription have been reported to result in Type 2 diabetes. We, therefore, aimed to clarify the role of this Ala45Thr polymorphism in the susceptibility to Type 1a, immune-mediated, diabetes of child-onset Japanese patients. Eighty patients with child-onset Type 1 diabetes were examined along with 121 non-diabetic subjects as the controls. The polymorphism in Ala45Thr was defined using the PCR-RFLP method. The GAD Ab, IA-2 Ab, HLA-DRB1 genotypes and residual beta-cell function at 3 years from onset were evaluated in relation to the difference in this polymorphism. The frequency of the Ala45Thr heterozygotes was significantly higher in the Type 1 diabetic patients than in the controls (21.3 versus 9.9%, P=0.0252). The frequency of loss of beta-cell function was higher in heterozygotes patients than in wild type homozygotes patients (P=0.0112). Type 1 diabetic patients with DRB1*0901 allele showed a significantly higher frequency, 27.9%, of the Ala45Thr variant than the controls (P=0.0041). In conclusion, the Ala45Thr polymorphism contributes to the risk of development of, and to the early deterioration of beta-cell function, in Type 1a diabetes among the Japanese population.
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Affiliation(s)
- Mie Mochizuki
- Departments of Pediatrics, Yamanashi Medical University, Shimokato 1110, Tamaho-machi, Nakakoma-gun, 409-3898, Yamanashi, Japan
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16
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Abstract
Type 1 diabetes is a multifactorial disease in which the insulin producing beta-cells of the pancreas are destroyed by the immune system, a process determined by the activity of major histocompatibility complex (MHC)-restricted T lymphocytes. Progress has been made in elucidating genetic factors involved in Type 1 diabetes in Caucasians, with less data available from Asia. For Asians, the human MHC locus (HLA region), especially the class II region, is the major susceptibility interval. The role of IDDM2, the insulin locus, has been questioned in Asia. In contrast to Caucasians, Asian populations have a very low incidence of Type 1 diabetes (0.4-1.1 cases/year/100 000 individuals). This low incidence rate in the Asian population may be related to the population frequency distribution of susceptible Type 1 diabetes genes, especially of HLA. The overall risk for Type 1 diabetes from HLA DR and DQ is determined by polymorphic residues (alleles) and particular combinations of alleles (haplotypes and genotypes) in a given individual. In Asians, it is very common that a protective DR4 allele is associated with susceptible DQ alleles while neutral/protective DQ alleles are associated with the susceptible DR4 alleles. Our analyses indicate that the counterbalancing between susceptible DRB1 and protective DQB1, and vice versa, is a factor that may contribute to the low incidence of diabetes in Asians. We find that identical HLA DRB1-DQB1 haplotypes of Asians and Caucasians have similar transmission to diabetic children and similar associations with diabetes. Moreover, the association with diabetes and transmission to a diabetic offspring of DR4 haplotypes varies depending on the haplotype borne on the homologous chromosome. This might contribute not only to the synergistic effect of DR3/4, but also to the susceptibility influence of DQB1*0401 haplotypes confined to DR4/X. High-risk DR4 subtypes were predominant in DR4/X, whereas protective DR4 subtypes were observed mainly in the DR3/4 genotype. Since in Asians DQB1*0401 is in linkage disequilibrium (LD) with DRB1*0405, we find more DRB1*0405-DQB1*0401 haplotypes in patients with DR4/X than in patients with DR3/4, suggesting that the contribution of the DRB1 locus may be greater in DR4/X than in DR3/4 genotypes. Several genome scans suggested additional susceptibility intervals and provided supporting evidence for several previously reported linkages. Other studies focused on the confirmation of linkage using multipoint sib-pair analyses with densely spaced markers and multiethnic collection of families. Although significant and consistent linkage evidence was reported for the susceptibility intervals IDDM12 (on 2q33) even in Asia, evidence for most other intervals varies in different data sets. LD mapping has become an increasingly important tool for both confirmation and fine-mapping of susceptibility intervals, as well as identification of etiological mutations. The examination of large and ethnically varied data sets including those of Asia has allowed identification of haplotypes that differ only at a single codon in a single locus. As more data become available, the study of pairs of haplotypes which differ at a single polymorphic site, but have different effects on disease susceptibility, should allow more precise definition of the polymorphisms involved in the disease process.
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Affiliation(s)
- Y Park
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Hanyang University Hospital, Seoul, Korea
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18
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Abstract
Traditional schemes of classifying nervous system malformations are based on descriptive morphogenesis of anatomic processes of ontogenesis, such as neurulation, neuroblast migration, and axonal pathfinding. This proposal is a first attempt to incorporate the recent molecular genetic data that explain programming of development etiologically. A scheme based purely on genetic mutations would not be practical, in part because only in a few dysgeneses are the specific defects known, but also because several genes might be involved sequentially and many genes inhibit or augment the expression of others. The same genes serve different functions at different stages and are involved in multiple organ systems. Some complex malformations, such as holoprosencephaly, result from several unrelated defective genes. Finally, a pure genetic classification would be too inflexible to incorporate some anatomic criteria. The basis for the proposed scheme is, therefore, disturbances in patterns of genetic expression; polarity gradients of the axes of the neural tube (eg, upregulation or downregulation of genetic influences); segmentation (eg, deletions of specific neuromeres, ectopic expression); mutations that cause change in cell lineage (eg, dysplastic gangliocytoma of cerebellum, myofiber differentiation within brain); and specific genes or molecules that mediate neuroblast migration in its early (eg, filamin-1), middle (eg, LIS1, double-cortin), or late course (eg, reelin, L1-CAM). The proposed scheme undoubtedly will undergo many future revisions, but it provides a starting point using currently available data.
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Affiliation(s)
- H B Sarnat
- Department of Neurology, University of Washington School of Medicine, Seattle, USA.
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Przyborski SA, Morton IE, Wood A, Andrews PW. Developmental regulation of neurogenesis in the pluripotent human embryonal carcinoma cell line NTERA-2. Eur J Neurosci 2000; 12:3521-8. [PMID: 11029621 DOI: 10.1046/j.1460-9568.2000.00230.x] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Embryonal carcinoma (EC) cells provide a caricature of pluripotent embryonic stem (ES) cells and may be used as surrogates for investigating the mechanisms that regulate cell differentiation during embryonic development. NTERA-2 is a human EC cell line that differentiates in response to retinoic acid yielding cells that include terminally differentiated neurons. The expression of genes known to be involved in the formation of the vertebrate nervous system was examined during retinoic acid-induced NTERA-2 differentiation. Differentiation of these human EC cells into neurons could be divided into three sequential phases. During phase 1, in the first week of differentiation, hath1 mRNA showed a small transient increase that correlated with the rapid accumulation of nestin message, a marker of neuroprogenitors. Transcripts of nestin were quickly downregulated during phase 2 as expression of neuroD1, characteristic of neuroprogenitors exiting the cell cycle, was induced. A neural cell surface antigen, detected by the monoclonal antibody A2B5, was expressed by cells exiting the cell cycle, correlating with the expression of neuroD1 as the cells became post-mitotic. Markers of mature neural cells (e.g. synaptophysin and neuron-specific enolase) were subsequently increased during phase 3 and were maintained. This regulated pattern of gene expression and commitment to the neural lineage indicates that differentiation of NTERA-2 neurons in vitro follows a similar pathway to that observed by neural ectodermal precursors during vertebrate neurogenesis in vivo.
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Affiliation(s)
- S A Przyborski
- Department of Biomedical Science, University of Sheffield, Western Bank, Sheffield S10 2TN, UK
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20
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Recent advances in the genetics of maturity-onset diabetes of the young and other forms of autosomal dominant diabetes. ACTA ACUST UNITED AC 2000. [DOI: 10.1097/00060793-200008000-00005] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Affiliation(s)
- H B Sarnat
- Department of Neurology, University of Washington School of Medicine, Seattle, USA.
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22
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Malecki MT, Jhala US, Antonellis A, Fields L, Doria A, Orban T, Saad M, Warram JH, Montminy M, Krolewski AS. Mutations in NEUROD1 are associated with the development of type 2 diabetes mellitus. Nat Genet 1999; 23:323-8. [PMID: 10545951 DOI: 10.1038/15500] [Citation(s) in RCA: 389] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The helix-loop-helix (HLH) protein NEUROD1 (also known as BETA2) functions as a regulatory switch for endocrine pancreatic development. In mice homozygous for a targeted disruption of Neurod, pancreatic islet morphogenesis is abnormal and overt diabetes develops due in part to inadequate expression of the insulin gene (Ins2). NEUROD1, following its heterodimerization with the ubiquitous HLH protein E47, regulates insulin gene (INS) expression by binding to a critical E-box motif on the INS promoter. Here we describe two mutations in NEUROD1, which are associated with the development of type 2 diabetes in the heterozygous state. The first, a missense mutation at Arg 111 in the DNA-binding domain, abolishes E-box binding activity of NEUROD1. The second mutation gives rise to a truncated polypeptide lacking the carboxy-terminal trans-activation domain, a region that associates with the co-activators CBP and p300 (refs 3,4). The clinical profile of patients with the truncated NEUROD1 polypeptide is more severe than that of patients with the Arg 111 mutation. Our findings suggest that deficient binding of NEUROD1 or binding of a transcriptionally inactive NEUROD1 polypeptide to target promoters in pancreatic islets leads to the development of type 2 diabetes in humans.
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Affiliation(s)
- M T Malecki
- Research Division, Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts, USA
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23
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Naya FJ, Huang HP, Qiu Y, Mutoh H, DeMayo FJ, Leiter AB, Tsai MJ. Diabetes, defective pancreatic morphogenesis, and abnormal enteroendocrine differentiation in BETA2/neuroD-deficient mice. Genes Dev 1997; 11:2323-34. [PMID: 9308961 PMCID: PMC316513 DOI: 10.1101/gad.11.18.2323] [Citation(s) in RCA: 753] [Impact Index Per Article: 27.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/1997] [Accepted: 07/29/1997] [Indexed: 02/05/2023]
Abstract
Candidate transcription factors involved in pancreatic endocrine development have been isolated using insulin gene regulation as a paradigm. The cell-type restricted basic helix-loop-helix (bHLH) gene, BETA2/NeuroD, expressed in pancreatic endocrine cells, the intestine, and the brain, activates insulin gene transcription and can induce neurons to differentiate. To understand the importance of BETA2 in pancreatic endocrine cell differentiation, mice lacking a functional BETA2 gene were generated by gene targeting experiments. Mice carrying a targeted disruption of the BETA2 gene developed severe diabetes and died perinatally. Homozygous BETA2 null mice had a striking reduction in the number of insulin-producing beta cells and failed to develop mature islets. Islet morphogenesis appeared to be arrested between E14.5 and E17.5, a period characterized by major expansion of the beta cell population. The presence of severe diabetes in these mice suggests that proper islet structure plays an important role in blood glucose homeostasis. In addition, secretin- and cholecystokinin-producing enteroendocrine cells failed to develop in the absence of BETA2. The absence of these two pancreatic secretagogs may explain the abnormal cellular polarity and inability to secrete zymogen granules in pancreatic acinar exocrine cells. The nervous system appeared to develop normally, despite abundant expression of BETA2 in differentiating neurons. Thus, BETA2 is critical for the normal development of several specialized cell types arising from the gut endoderm.
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Affiliation(s)
- F J Naya
- Department of Cell Biology, Baylor College of Medicine, Houston, Texas 77030, USA
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24
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Acharya HR, Dooley CM, Thoreson WB, Ahmad I. cDNA cloning and expression analysis of NeuroD mRNA in human retina. Biochem Biophys Res Commun 1997; 233:459-63. [PMID: 9144558 DOI: 10.1006/bbrc.1997.6483] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We have shown that bHLH proteins are involved in mammalian retinal development. Here we report the identification and analysis of the expression of a neurogenic differentiation gene, NeuroD, in human retina. In situ hybridization and immunocytochemical analyses of adult retina showed that NeuroD transcripts and NeuroD immunoreactivity are predominantly localized to the outer nuclear layer which contains the photoreceptors. Southern analysis of PCR-amplified cDNA revealed that NeuroD mRNA is also expressed in fetal human retina. Fetal monkey retina was used to analyse the spatial distribution of NeuroD in the developing retina. Both NeuroD transcripts and immunoreactivity are largely detected in the outer neuroblastic layer. Therefore, NeuroD may be involved in the differentiation as well as maintenance of the differentiated properties of photoreceptors.
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Affiliation(s)
- H R Acharya
- Department of Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha 68198-6395, USA
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25
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Tamimi RM, Steingrimsson E, Montgomery-Dyer K, Copeland NG, Jenkins NA, Tapscott SJ. NEUROD2 and NEUROD3 genes map to human chromosomes 17q12 and 5q23-q31 and mouse chromosomes 11 and 13, respectively. Genomics 1997; 40:355-7. [PMID: 9119405 DOI: 10.1006/geno.1996.4578] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
NEUROD2 and NEUROD3 are transcription factors involved in neurogenesis that are related to the basic helix-loop-helix protein NEUROD. NEUROD2 maps to human chromosome 17q12 and mouse chromosome 11. NEUROD3 maps to human chromosome 5q23-q31 and mouse chromosome 13.
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Affiliation(s)
- R M Tamimi
- Fred Hutchinson Cancer Research Center, Seattle, Washington 98104, USA
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26
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McCormick MB, Tamimi RM, Snider L, Asakura A, Bergstrom D, Tapscott SJ. NeuroD2 and neuroD3: distinct expression patterns and transcriptional activation potentials within the neuroD gene family. Mol Cell Biol 1996; 16:5792-800. [PMID: 8816493 PMCID: PMC231580 DOI: 10.1128/mcb.16.10.5792] [Citation(s) in RCA: 141] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
We have identified two new genes, neuroD2 and neuroD3, on the basis of their similarity to the neurogenic basic-helix-loop-helix (bHLH) gene neuroD. The predicted amino acid sequence of neuroD2 shows a high degree of homology to neuroD and MATH-2/NEX-1 in the bHLH region, whereas neuroD3 is a more distantly related family member. neuroD3 is expressed transiently during embryonic development, with the highest levels of expression between days 10 and 12. neuroD2 is initially expressed at embryonic day 11, with persistent expression in the adult nervous system. In situ and Northern (RNA) analyses demonstrate that different regions of the adult nervous system have different relative amounts of neuroD and neuroD2 RNA. Similar to neuroD, expression of neuroD2 in developing Xenopus laevis embryos results in ectopic neurogenesis, indicating that neuroD2 mediates neuronal differentiation. Transfection of vectors expressing neuroD and neuroD2 into P19 cells shows that both can activate expression through simple E-box-driven reporter constructs and can activate a reporter driven by the neuroD2 promoter region, but the GAP-43 promoter is preferentially activated by neuroD2. The noncongruent expression pattern and target gene specificity of these highly related neurogenic bHLH proteins make them candidates for conferring specific aspects of the neuronal phenotype.
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Affiliation(s)
- M B McCormick
- Fred Hutchinson Cancer Research Center, Seattle, Washington 98104, USA
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