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Haws W, England S, Grieb G, Susana G, Hernandez S, Mirer H, Lewis K. Analyses of binding partners and functional domains for the developmentally essential protein Hmx3a/HMX3. Sci Rep 2023; 13:1151. [PMID: 36670152 PMCID: PMC9859826 DOI: 10.1038/s41598-023-27878-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Accepted: 01/09/2023] [Indexed: 01/22/2023] Open
Abstract
HMX3 is a homeodomain protein with essential roles in CNS and ear development. Homeodomains are DNA-binding domains and hence homeodomain-containing proteins are usually assumed to be transcription factors. However, intriguingly, our recent data suggest that zebrafish Hmx3a may not require its homeodomain to function, raising the important question of what molecular interactions mediate its effects. To investigate this, we performed a yeast two-hybrid screen and identified 539 potential binding partners of mouse HMX3. Using co-immunoprecipitation, we tested whether a prioritized subset of these interactions are conserved in zebrafish and found that Tle3b, Azin1b, Prmt2, Hmgb1a, and Hmgn3 bind Hmx3a. Next, we tested whether these proteins bind the products of four distinct hmx3a mutant alleles that all lack the homeodomain. Embryos homozygous for two of these alleles develop abnormally and die, whereas zebrafish homozygous for the other two alleles are viable. We found that all four mutations abrogate binding to Prmt2 and Tle3b, whereas Azin1b binding was preserved in all cases. Interestingly, Hmgb1a and Hmgn3 had more affinity for products of the viable mutant alleles. These data shed light on how HMX3/Hmx3a might function at a molecular level and identify new targets for future study in these vital developmental processes.
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Affiliation(s)
- William Haws
- Department of Biology, Syracuse University, 107 College Place, Syracuse, NY, 13244, USA
| | - Samantha England
- Department of Biology, Syracuse University, 107 College Place, Syracuse, NY, 13244, USA
| | - Ginny Grieb
- Department of Biology, Syracuse University, 107 College Place, Syracuse, NY, 13244, USA
| | - Gabriela Susana
- Department of Biology, Syracuse University, 107 College Place, Syracuse, NY, 13244, USA
| | - Sophie Hernandez
- Department of Biology, Syracuse University, 107 College Place, Syracuse, NY, 13244, USA
| | - Hunter Mirer
- Department of Biology, Syracuse University, 107 College Place, Syracuse, NY, 13244, USA
| | - Katharine Lewis
- Department of Biology, Syracuse University, 107 College Place, Syracuse, NY, 13244, USA.
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2
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Farley SJ, Grishok A, Zeldich E. Shaking up the silence: consequences of HMGN1 antagonizing PRC2 in the Down syndrome brain. Epigenetics Chromatin 2022; 15:39. [PMID: 36463299 PMCID: PMC9719135 DOI: 10.1186/s13072-022-00471-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Accepted: 11/11/2022] [Indexed: 12/04/2022] Open
Abstract
Intellectual disability is a well-known hallmark of Down Syndrome (DS) that results from the triplication of the critical region of human chromosome 21 (HSA21). Major studies were conducted in recent years to gain an understanding about the contribution of individual triplicated genes to DS-related brain pathology. Global transcriptomic alterations and widespread changes in the establishment of neural lineages, as well as their differentiation and functional maturity, suggest genome-wide chromatin organization alterations in trisomy. High Mobility Group Nucleosome Binding Domain 1 (HMGN1), expressed from HSA21, is a chromatin remodeling protein that facilitates chromatin decompaction and is associated with acetylated lysine 27 on histone H3 (H3K27ac), a mark correlated with active transcription. Recent studies causatively linked overexpression of HMGN1 in trisomy and the development of DS-associated B cell acute lymphoblastic leukemia (B-ALL). HMGN1 has been shown to antagonize the activity of the Polycomb Repressive Complex 2 (PRC2) and prevent the deposition of histone H3 lysine 27 trimethylation mark (H3K27me3), which is associated with transcriptional repression and gene silencing. However, the possible ramifications of the increased levels of HMGN1 through the derepression of PRC2 target genes on brain cell pathology have not gained attention. In this review, we discuss the functional significance of HMGN1 in brain development and summarize accumulating reports about the essential role of PRC2 in the development of the neural system. Mechanistic understanding of how overexpression of HMGN1 may contribute to aberrant brain cell phenotypes in DS, such as altered proliferation of neural progenitors, abnormal cortical architecture, diminished myelination, neurodegeneration, and Alzheimer's disease-related pathology in trisomy 21, will facilitate the development of DS therapeutic approaches targeting chromatin.
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Affiliation(s)
- Sean J. Farley
- grid.189504.10000 0004 1936 7558Department of Anatomy and Neurobiology, Boston University Chobanian & Avedisian School of Medicine, Boston, MA USA
| | - Alla Grishok
- grid.189504.10000 0004 1936 7558Department of Biochemistry, Boston University Chobanian & Avedisian School of Medicine, Boston, MA USA ,grid.189504.10000 0004 1936 7558Boston University Genome Science Institute, Boston University Chobanian & Avedisian School of Medicine, Boston, MA USA
| | - Ella Zeldich
- Department of Anatomy and Neurobiology, Boston University Chobanian & Avedisian School of Medicine, Boston, MA, USA.
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3
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Rif1 and Hmgn3 regulate the conversion of murine trophoblast stem cells. Cell Rep 2022; 38:110570. [PMID: 35354046 DOI: 10.1016/j.celrep.2022.110570] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 01/24/2022] [Accepted: 03/03/2022] [Indexed: 11/22/2022] Open
Abstract
The appearance of trophectoderm (TE) is a hallmark event in preimplantation development during murine embryogenesis. However, little is known about the mechanisms underlying TE specification. We find that the depletion of Rif1 breaks down the barrier to the transition from embryonic stem cells (ESCs) to trophoblast stem cells (TSCs). Rif1-null-induced TSCs show typical TE properties and the potential to differentiate into terminal trophoblast lineages. Global transcriptome analysis reveal that Rif1 deletion activates 2-cell embryo (2C)-related genes and induces a totipotent-like state. Chimeric assays further confirm that Rif1-null ESCs contribute to the functional placenta in addition to the fetus on embryonic day 12.5. Furthermore, we show overexpression of Hmgn3, one of the key upregulated gene in Rif1-null ESCs, facilitates the induction of TSCs. Therefore, we report two key genes regulating the conversion of TSCs and provide insights for investigating TE specification.
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Spatial and Temporal Expression of High-Mobility-Group Nucleosome-Binding (HMGN) Genes in Brain Areas Associated with Cognition in Individuals with Down Syndrome. Genes (Basel) 2021; 12:genes12122000. [PMID: 34946949 PMCID: PMC8700945 DOI: 10.3390/genes12122000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Revised: 12/08/2021] [Accepted: 12/09/2021] [Indexed: 11/17/2022] Open
Abstract
DNA methylation and histone posttranslational modifications are epigenetics processes that contribute to neurophenotype of Down Syndrome (DS). Previous reports present strong evidence that nonhistone high-mobility-group N proteins (HMGN) are epigenetic regulators. They play important functions in various process to maintain homeostasis in the brain. We aimed to analyze the differential expression of five human HMGN genes in some brain structures and age ranks from DS postmortem brain samples. Methodology: We performed a computational analysis of the expression of human HMGN from the data of a DNA microarray experiment (GEO database ID GSE59630). Using the transformed log2 data, we analyzed the differential expression of five HMGN genes in several brain areas associated with cognition in patients with DS. Moreover, using information from different genome databases, we explored the co-expression and protein interactions of HMNGs with the histones of nucleosome core particle and linker H1 histone. Results: We registered that HMGN1 and HMGN5 were significantly overexpressed in the hippocampus and areas of prefrontal cortex including DFC, OFC, and VFC of DS patients. Age-rank comparisons between euploid control and DS individuals showed that HMGN2 and HMGN4 were overexpressed in the DS brain at 16 to 22 gestation weeks. From the BioGRID database, we registered high interaction scores of HMGN2 and HMGN4 with Hist1H1A and Hist1H3A. Conclusions: Overall, our results give strong evidence to propose that DS would be an epigenetics-based aneuploidy. Remodeling brain chromatin by HMGN1 and HMGN5 would be an essential pathway in the modification of brain homeostasis in DS.
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5
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Biological Functions of HMGN Chromosomal Proteins. Int J Mol Sci 2020; 21:ijms21020449. [PMID: 31936777 PMCID: PMC7013550 DOI: 10.3390/ijms21020449] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 01/02/2020] [Accepted: 01/08/2020] [Indexed: 12/14/2022] Open
Abstract
Chromatin plays a key role in regulating gene expression programs necessary for the orderly progress of development and for preventing changes in cell identity that can lead to disease. The high mobility group N (HMGN) is a family of nucleosome binding proteins that preferentially binds to chromatin regulatory sites including enhancers and promoters. HMGN proteins are ubiquitously expressed in all vertebrate cells potentially affecting chromatin function and epigenetic regulation in multiple cell types. Here, we review studies aimed at elucidating the biological function of HMGN proteins, focusing on their possible role in vertebrate development and the etiology of disease. The data indicate that changes in HMGN levels lead to cell type-specific phenotypes, suggesting that HMGN optimize epigenetic processes necessary for maintaining cell identity and for proper execution of specific cellular functions. This manuscript contains tables that can be used as a comprehensive resource for all the English written manuscripts describing research aimed at elucidating the biological function of the HMGN protein family.
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Goodnight AV, Kremsky I, Khampang S, Jung YH, Billingsley JM, Bosinger SE, Corces VG, Chan AWS. Chromatin accessibility and transcription dynamics during in vitro astrocyte differentiation of Huntington's Disease Monkey pluripotent stem cells. Epigenetics Chromatin 2019; 12:67. [PMID: 31722751 PMCID: PMC6852955 DOI: 10.1186/s13072-019-0313-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Accepted: 10/25/2019] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Huntington's Disease (HD) is a fatal neurodegenerative disorder caused by a CAG repeat expansion, resulting in a mutant huntingtin protein. While it is now clear that astrocytes are affected by HD and significantly contribute to neuronal dysfunction and pathogenesis, the alterations in the transcriptional and epigenetic profiles in HD astrocytes have yet to be characterized. Here, we examine global transcription and chromatin accessibility dynamics during in vitro astrocyte differentiation in a transgenic non-human primate model of HD. RESULTS We found global changes in accessibility and transcription across different stages of HD pluripotent stem cell differentiation, with distinct trends first observed in neural progenitor cells (NPCs), once cells have committed to a neural lineage. Transcription of p53 signaling and cell cycle pathway genes was highly impacted during differentiation, with depletion in HD NPCs and upregulation in HD astrocytes. E2F target genes also displayed this inverse expression pattern, and strong associations between E2F target gene expression and accessibility at nearby putative enhancers were observed. CONCLUSIONS The results suggest that chromatin accessibility and transcription are altered throughout in vitro HD astrocyte differentiation and provide evidence that E2F dysregulation contributes to aberrant cell-cycle re-entry and apoptosis throughout the progression from NPCs to astrocytes.
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Affiliation(s)
- Alexandra V Goodnight
- Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center, Atlanta, GA, 30322, USA
- Department of Human Genetics, Emory University, Atlanta, GA, 30322, USA
- Genetics and Molecular Biology Program, Graduate Division of Biological and Biomedical Sciences, 1462 Clifton Rd, Atlanta, GA, 30322, USA
| | - Isaac Kremsky
- Department of Human Genetics, Emory University, Atlanta, GA, 30322, USA
| | - Sujittra Khampang
- Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center, Atlanta, GA, 30322, USA
- Department of Human Genetics, Emory University, Atlanta, GA, 30322, USA
- Embryonic Stem Cell Research Center, School of Biotechnology, Suranaree University of Technology, Nakhon Ratchasima, Thailand
| | - Yoon Hee Jung
- Department of Human Genetics, Emory University, Atlanta, GA, 30322, USA
| | - James M Billingsley
- Division of Microbiology and Immunology, Yerkes National Primate Research Center, Emory University, Atlanta, GA, USA
| | - Steven E Bosinger
- Division of Microbiology and Immunology, Yerkes National Primate Research Center, Emory University, Atlanta, GA, USA
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, GA, USA
| | - Victor G Corces
- Department of Human Genetics, Emory University, Atlanta, GA, 30322, USA.
- Genetics and Molecular Biology Program, Graduate Division of Biological and Biomedical Sciences, 1462 Clifton Rd, Atlanta, GA, 30322, USA.
| | - Anthony W S Chan
- Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center, Atlanta, GA, 30322, USA.
- Department of Human Genetics, Emory University, Atlanta, GA, 30322, USA.
- Genetics and Molecular Biology Program, Graduate Division of Biological and Biomedical Sciences, 1462 Clifton Rd, Atlanta, GA, 30322, USA.
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7
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Yoffe Y, David M, Kalaora R, Povodovski L, Friedlander G, Feldmesser E, Ainbinder E, Saada A, Bialik S, Kimchi A. Cap-independent translation by DAP5 controls cell fate decisions in human embryonic stem cells. Genes Dev 2017; 30:1991-2004. [PMID: 27664238 PMCID: PMC5066241 DOI: 10.1101/gad.285239.116] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Accepted: 08/18/2016] [Indexed: 12/21/2022]
Abstract
In this study, Yoffe et al. provide insight into a new regulatory mechanism that is critical for stem cell fate decisions toward several cell lineages. They found that DAP5-mediated translation of a specific set of proteins is critical for the transition from pluripotency to differentiation, highlighting the importance of cap-independent translation in stem cell fate decisions. Multiple transcriptional and epigenetic changes drive differentiation of embryonic stem cells (ESCs). This study unveils an additional level of gene expression regulation involving noncanonical, cap-independent translation of a select group of mRNAs. This is driven by death-associated protein 5 (DAP5/eIF4G2/NAT1), a translation initiation factor mediating IRES-dependent translation. We found that the DAP5 knockdown from human ESCs (hESCs) resulted in persistence of pluripotent gene expression, delayed induction of differentiation-associated genes in different cell lineages, and defective embryoid body formation. The latter involved improper cellular organization, lack of cavitation, and enhanced mislocalized apoptosis. RNA sequencing of polysome-associated mRNAs identified candidates with reduced translation efficiency in DAP5-depleted hESCs. These were enriched in mitochondrial proteins involved in oxidative respiration, a pathway essential for differentiation, the significance of which was confirmed by the aberrant mitochondrial morphology and decreased oxidative respiratory activity in DAP5 knockdown cells. Further analysis identified the chromatin modifier HMGN3 as a cap-independent DAP5 translation target whose knockdown resulted in defective differentiation. Thus, DAP5-mediated translation of a specific set of proteins is critical for the transition from pluripotency to differentiation, highlighting the importance of cap-independent translation in stem cell fate decisions.
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Affiliation(s)
- Yael Yoffe
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Maya David
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Rinat Kalaora
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Lital Povodovski
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Gilgi Friedlander
- Nancy and Stephen Grand Israel National Center for Personalized Medicine, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Ester Feldmesser
- Bioinformatics Unit, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Elena Ainbinder
- Stem Cell Core Unit, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Ann Saada
- Monique and Jacques Roboh Department of Genetic Research, Hadassah-Hebrew University Medical Center, Jerusalem 91120, Israel; Department of Genetics and Metabolic Diseases, Hadassah-Hebrew University Medical Center, Jerusalem 91120, Israel
| | - Shani Bialik
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Adi Kimchi
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
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8
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Li DD, Guo CH, Yue L, Duan CC, Yang ZQ, Cao H, Guo B, Yue ZP. Expression, regulation and function of Hmgn3 during decidualization in mice. Mol Cell Endocrinol 2015; 413:13-25. [PMID: 26112184 DOI: 10.1016/j.mce.2015.05.038] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Revised: 05/26/2015] [Accepted: 05/27/2015] [Indexed: 01/12/2023]
Abstract
Although Hmgn3 is involved in the regulation of development and cellular differentiation, its physiological roles on decidualization are still unknown. Here we showed that Hmgn3 was highly expressed in the decidua and decidualizing stromal cells. Overexpression of Hmgn3 variants, Hmgn3a or Hmgn3b, enhanced the expression of decidualization markers Prl8a2 and Prl3c1, whereas inhibition of Hmgn3 reduced their expression. Hmgn3 could mediate the effects of Hoxa10 and cAMP on the expression of Prl8a2 and Prl3c1. Further study found that Hmgn3 directed the process of decidualization through influencing the expression of Hand2. Progesterone could induce the expression of Hmgn3 in the ovariectomized mouse uterus, uterine epithelial cells and stromal cells. Knockdown of Hoxa10 with siRNA alleviated the induction of progesterone and cAMP on Hmgn3 expression. Simultaneously, siRNA-mediated down-regulation of Hmgn3 in the uterine stromal cells could attenuate the effects of progesterone, cAMP and Hoxa10 on the expression of Hand2. Collectively, Hmgn3 may play an important role during mouse decidualization.
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Affiliation(s)
- Dang-Dang Li
- College of Veterinary Medicine, Jilin University, Changchun, PR China
| | - Chuan-Hui Guo
- College of Veterinary Medicine, Jilin University, Changchun, PR China
| | - Liang Yue
- College of Clinical Medicine, Jilin University, Changchun, PR China
| | - Cui-Cui Duan
- Institute of Agro-food Technology, Jilin Academy of Agricultural Sciences, Changchun, PR China
| | - Zhan-Qing Yang
- College of Veterinary Medicine, Jilin University, Changchun, PR China
| | - Hang Cao
- College of Veterinary Medicine, Jilin University, Changchun, PR China
| | - Bin Guo
- College of Veterinary Medicine, Jilin University, Changchun, PR China.
| | - Zhan-Peng Yue
- College of Veterinary Medicine, Jilin University, Changchun, PR China
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9
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Nagao M, Lanjakornsiripan D, Itoh Y, Kishi Y, Ogata T, Gotoh Y. High mobility group nucleosome-binding family proteins promote astrocyte differentiation of neural precursor cells. Stem Cells 2015; 32:2983-97. [PMID: 25069414 DOI: 10.1002/stem.1787] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Revised: 06/17/2014] [Accepted: 06/23/2014] [Indexed: 11/07/2022]
Abstract
Astrocytes are the most abundant cell type in the mammalian brain and are important for the functions of the central nervous system. Although previous studies have shown that the STAT signaling pathway or its regulators promote the generation of astrocytes from multipotent neural precursor cells (NPCs) in the developing mammalian brain, the molecular mechanisms that regulate the astrocytic fate decision have still remained largely unclear. Here, we show that the high mobility group nucleosome-binding (HMGN) family proteins, HMGN1, 2, and 3, promote astrocyte differentiation of NPCs during brain development. HMGN proteins were expressed in NPCs, Sox9(+) glial progenitors, and GFAP(+) astrocytes in perinatal and adult brains. Forced expression of either HMGN1, 2, or 3 in NPCs in cultures or in the late embryonic neocortex increased the generation of astrocytes at the expense of neurons. Conversely, knockdown of either HMGN1, 2, or 3 in NPCs suppressed astrocyte differentiation and promoted neuronal differentiation. Importantly, overexpression of HMGN proteins did not induce the phosphorylation of STAT3 or activate STAT reporter genes. In addition, HMGN family proteins did not enhance DNA demethylation and acetylation of histone H3 around the STAT-binding site of the gfap promoter. Moreover, knockdown of HMGN family proteins significantly reduced astrocyte differentiation induced by gliogenic signal ciliary neurotrophic factor, which activates the JAK-STAT pathway. Therefore, we propose that HMGN family proteins are novel chromatin regulatory factors that control astrocyte fate decision/differentiation in parallel with or downstream of the JAK-STAT pathway through modulation of the responsiveness to gliogenic signals.
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Affiliation(s)
- Motoshi Nagao
- Department of Rehabilitation for the Movement Functions, Research Institute, National Rehabilitation Center for Persons with Disabilities, Saitama, Japan
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10
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Kang R, Chen R, Zhang Q, Hou W, Wu S, Cao L, Huang J, Yu Y, Fan XG, Yan Z, Sun X, Wang H, Wang Q, Tsung A, Billiar TR, Zeh HJ, Lotze MT, Tang D. HMGB1 in health and disease. Mol Aspects Med 2014; 40:1-116. [PMID: 25010388 PMCID: PMC4254084 DOI: 10.1016/j.mam.2014.05.001] [Citation(s) in RCA: 701] [Impact Index Per Article: 70.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Accepted: 05/05/2014] [Indexed: 12/22/2022]
Abstract
Complex genetic and physiological variations as well as environmental factors that drive emergence of chromosomal instability, development of unscheduled cell death, skewed differentiation, and altered metabolism are central to the pathogenesis of human diseases and disorders. Understanding the molecular bases for these processes is important for the development of new diagnostic biomarkers, and for identifying new therapeutic targets. In 1973, a group of non-histone nuclear proteins with high electrophoretic mobility was discovered and termed high-mobility group (HMG) proteins. The HMG proteins include three superfamilies termed HMGB, HMGN, and HMGA. High-mobility group box 1 (HMGB1), the most abundant and well-studied HMG protein, senses and coordinates the cellular stress response and plays a critical role not only inside of the cell as a DNA chaperone, chromosome guardian, autophagy sustainer, and protector from apoptotic cell death, but also outside the cell as the prototypic damage associated molecular pattern molecule (DAMP). This DAMP, in conjunction with other factors, thus has cytokine, chemokine, and growth factor activity, orchestrating the inflammatory and immune response. All of these characteristics make HMGB1 a critical molecular target in multiple human diseases including infectious diseases, ischemia, immune disorders, neurodegenerative diseases, metabolic disorders, and cancer. Indeed, a number of emergent strategies have been used to inhibit HMGB1 expression, release, and activity in vitro and in vivo. These include antibodies, peptide inhibitors, RNAi, anti-coagulants, endogenous hormones, various chemical compounds, HMGB1-receptor and signaling pathway inhibition, artificial DNAs, physical strategies including vagus nerve stimulation and other surgical approaches. Future work further investigating the details of HMGB1 localization, structure, post-translational modification, and identification of additional partners will undoubtedly uncover additional secrets regarding HMGB1's multiple functions.
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Affiliation(s)
- Rui Kang
- Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA.
| | - Ruochan Chen
- Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA
| | - Qiuhong Zhang
- Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA
| | - Wen Hou
- Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA
| | - Sha Wu
- Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA
| | - Lizhi Cao
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China
| | - Jin Huang
- Department of Oncology, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China
| | - Yan Yu
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China
| | - Xue-Gong Fan
- Department of Infectious Diseases, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China
| | - Zhengwen Yan
- Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA; Department of Neurology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, Guangdong 510120, China
| | - Xiaofang Sun
- Key Laboratory for Major Obstetric Diseases of Guangdong Province, Key Laboratory of Reproduction and Genetics of Guangdong Higher Education Institutes, Experimental Department of Institute of Gynecology and Obstetrics, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong 510510, China
| | - Haichao Wang
- Laboratory of Emergency Medicine, The Feinstein Institute for Medical Research, Manhasset, NY 11030, USA
| | - Qingde Wang
- Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA
| | - Allan Tsung
- Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA
| | - Timothy R Billiar
- Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA
| | - Herbert J Zeh
- Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA
| | - Michael T Lotze
- Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA
| | - Daolin Tang
- Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA.
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11
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González-Romero R, Eirín-López JM, Ausió J. Evolution of high mobility group nucleosome-binding proteins and its implications for vertebrate chromatin specialization. Mol Biol Evol 2014; 32:121-31. [PMID: 25281808 DOI: 10.1093/molbev/msu280] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
High mobility group (HMG)-N proteins are a family of small nonhistone proteins that bind to nucleosomes (N). Despite the amount of information available on their structure and function, there is an almost complete lack of information on the molecular evolutionary mechanisms leading to their exclusive differentiation. In the present work, we provide evidence suggesting that HMGN lineages constitute independent monophyletic groups derived from a common ancestor prior to the diversification of vertebrates. Based on observations of the functional diversification across vertebrate HMGN proteins and on the extensive silent nucleotide divergence, our results suggest that the long-term evolution of HMGNs occurs under strong purifying selection, resulting from the lineage-specific functional constraints of their different protein domains. Selection analyses on independent lineages suggest that their functional specialization was mediated by bursts of adaptive selection at specific evolutionary times, in a small subset of codons with functional relevance-most notably in HMGN1, and in the rapidly evolving HMGN5. This work provides useful information to our understanding of the specialization imparted on chromatin metabolism by HMGNs, especially on the evolutionary mechanisms underlying their functional differentiation in vertebrates.
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Affiliation(s)
| | - José M Eirín-López
- Chromatin Structure and Evolution (CHROMEVOL) Group, Department of Biological Sciences, Florida International University
| | - Juan Ausió
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, Canada
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12
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Kugler JE, Horsch M, Huang D, Furusawa T, Rochman M, Garrett L, Becker L, Bohla A, Hölter SM, Prehn C, Rathkolb B, Racz I, Aguilar-Pimentel JA, Adler T, Adamski J, Beckers J, Busch DH, Eickelberg O, Klopstock T, Ollert M, Stöger T, Wolf E, Wurst W, Yildirim AÖ, Zimmer A, Gailus-Durner V, Fuchs H, Hrabě de Angelis M, Garfinkel B, Orly J, Ovcharenko I, Bustin M. High mobility group N proteins modulate the fidelity of the cellular transcriptional profile in a tissue- and variant-specific manner. J Biol Chem 2013; 288:16690-16703. [PMID: 23620591 DOI: 10.1074/jbc.m113.463315] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The nuclei of most vertebrate cells contain members of the high mobility group N (HMGN) protein family, which bind specifically to nucleosome core particles and affect chromatin structure and function, including transcription. Here, we study the biological role of this protein family by systematic analysis of phenotypes and tissue transcription profiles in mice lacking functional HMGN variants. Phenotypic analysis of Hmgn1(tm1/tm1), Hmgn3(tm1/tm1), and Hmgn5(tm1/tm1) mice and their wild type littermates with a battery of standardized tests uncovered variant-specific abnormalities. Gene expression analysis of four different tissues in each of the Hmgn(tm1/tm1) lines reveals very little overlap between genes affected by specific variants in different tissues. Pathway analysis reveals that loss of an HMGN variant subtly affects expression of numerous genes in specific biological processes. We conclude that within the biological framework of an entire organism, HMGNs modulate the fidelity of the cellular transcriptional profile in a tissue- and HMGN variant-specific manner.
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Affiliation(s)
- Jamie E Kugler
- Protein Section, Laboratory of Metabolism, Center for Cancer Research, NCI, National Institutes of Health, Bethesda, Maryland 20892
| | - Marion Horsch
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany
| | - Di Huang
- Computational Biology Branch, NCBI, National Library of Medicine, National Institutes of Health, Bethesda, Maryland 20892
| | - Takashi Furusawa
- Protein Section, Laboratory of Metabolism, Center for Cancer Research, NCI, National Institutes of Health, Bethesda, Maryland 20892
| | - Mark Rochman
- Protein Section, Laboratory of Metabolism, Center for Cancer Research, NCI, National Institutes of Health, Bethesda, Maryland 20892
| | - Lillian Garrett
- German Mouse Clinic, Institute of Developmental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
| | - Lore Becker
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany; Department of Neurology, Friedrich-Baur-Institut, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Alexander Bohla
- German Mouse Clinic, Comprehensive Pneumology Center, Institute of Lung Biology and Disease, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany; German Center for Lung Research, Munich, Germany
| | - Sabine M Hölter
- German Mouse Clinic, Institute of Developmental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
| | - Cornelia Prehn
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany
| | - Birgit Rathkolb
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany; Molecular Animal Breeding and Biotechnology, Gene Center, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Ildikó Racz
- Institute of Molecular Psychiatry, University of Bonn, Bonn, Germany
| | - Juan Antonio Aguilar-Pimentel
- Center of Allergy and Environment, Technische Universität München, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany; Department of Dermatology and Allergy, Biederstein, Technische Universität München and Clinical Research Division of Molecular and Clinical Allergotoxicology, Technische Universität München, Munich, Germany
| | - Thure Adler
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany; Institute of Medical Microbiology, Immunology, and Hygiene, Technische Universität München, München, Germany
| | - Jerzy Adamski
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany; Experimental Genetics, Center of Life and Food Sciences Weihenstephan, Technische Universität München, 85350 Freising-Weihenstephan, Germany
| | - Johannes Beckers
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany; Experimental Genetics, Center of Life and Food Sciences Weihenstephan, Technische Universität München, Freising-Weihenstephan, Germany
| | - Dirk H Busch
- Institute of Medical Microbiology, Immunology, and Hygiene, Technische Universität München, München, Germany
| | - Oliver Eickelberg
- German Mouse Clinic, Comprehensive Pneumology Center, Institute of Lung Biology and Disease, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany; German Center for Lung Research, Munich, Germany
| | - Thomas Klopstock
- Department of Neurology, Friedrich-Baur-Institut, Ludwig-Maximilians-Universität München, Munich, Germany; German Center for Vertigo and Balance Disorders, Technische Universität München, Munich, Germany; Deutsches Zentrum für Neurodegenerative Erkrankungen-German Center for Neurodegenerative Diseases, Site Munich, Munich, Germany
| | - Markus Ollert
- Department of Dermatology and Allergy, Biederstein, Technische Universität München and Clinical Research Division of Molecular and Clinical Allergotoxicology, Technische Universität München, Munich, Germany
| | - Tobias Stöger
- German Mouse Clinic, Comprehensive Pneumology Center, Institute of Lung Biology and Disease, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany; German Center for Lung Research, Munich, Germany
| | - Eckhard Wolf
- Molecular Animal Breeding and Biotechnology, Gene Center, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Wolfgang Wurst
- German Mouse Clinic, Institute of Developmental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany; Deutsches Zentrum für Neurodegenerative Erkrankungen-German Center for Neurodegenerative Diseases, Site Munich, Munich, Germany; Max Planck Institute of Psychiatry, Munich, Germany; Developmental Genetics, Technische Universität München c/o Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
| | - Ali Önder Yildirim
- German Mouse Clinic, Comprehensive Pneumology Center, Institute of Lung Biology and Disease, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany; German Center for Lung Research, Munich, Germany
| | - Andreas Zimmer
- Institute of Molecular Psychiatry, University of Bonn, Bonn, Germany
| | - Valérie Gailus-Durner
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany
| | - Helmut Fuchs
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany
| | - Martin Hrabě de Angelis
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany; Experimental Genetics, Center of Life and Food Sciences Weihenstephan, Technische Universität München, Freising-Weihenstephan, Germany; German Center for Vertigo and Balance Disorders, Technische Universität München, Munich, Germany; German Center for Diabetes Research, Neuherberg, Germany
| | - Benny Garfinkel
- Department of Biological Chemistry, The Alexander Silberman Institute of Life Sciences, Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Joseph Orly
- Department of Biological Chemistry, The Alexander Silberman Institute of Life Sciences, Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Ivan Ovcharenko
- Computational Biology Branch, NCBI, National Library of Medicine, National Institutes of Health, Bethesda, Maryland 20892
| | - Michael Bustin
- Protein Section, Laboratory of Metabolism, Center for Cancer Research, NCI, National Institutes of Health, Bethesda, Maryland 20892.
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Furusawa T, Cherukuri S. Developmental function of HMGN proteins. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2010; 1799:69-73. [PMID: 20123069 DOI: 10.1016/j.bbagrm.2009.11.011] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2009] [Revised: 11/02/2009] [Accepted: 11/05/2009] [Indexed: 11/24/2022]
Abstract
High mobility group N (HMGN) proteins are the only nuclear proteins known to specifically recognize the generic structure of the 147-bp nucleosome core particle. Both in vitro and in vivo experiments demonstrate that HMGN proteins are involved in epigenetic regulation by modulating chromatin structure and levels of posttranslational modifications of nucleosomal histones. Expression of HMGN proteins is developmentally regulated, and the loss or overexpression of these proteins can lead to developmental abnormalities. This review will focus on the role and on the possible molecular mechanism whereby HMGN proteins affect cellular differentiation and development.
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Affiliation(s)
- Takashi Furusawa
- Protein Section, Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Building 37, Room 3122, 9000 Rockville Pike, Bethesda, MD 20892, USA.
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14
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Kurahashi T, Furusawa T, Ueda T, Bustin M. The nucleosome binding protein HMGN3 is expressed in pancreatic alpha-cells and affects plasma glucagon levels in mice. J Cell Biochem 2010; 109:49-57. [PMID: 19885867 DOI: 10.1002/jcb.22377] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Glucose homeostasis requires the coordinated actions of various organs and is critically dependent on the proper functioning of the various cell types present in the pancreatic Langerhans islets. Here we report that chromatin architectural protein HMGN3 is highly expressed in all pancreatic endocrine islet cells, and that Hmgn3-/- mice which have a mild diabetic phenotype, have reduced glucagon levels in their blood. To elucidate the mechanism leading to altered glucagon secretion of Hmgn3-/- mice, we tested whether HMGN3 affect glucagon synthesis and secretion in alphaTC1-9 cells, a glucagon secreting cell line that is used to study pancreatic alpha-cell function. We find that in these cells deletion of either HMGN3 or other HMGN variants, does not significantly affect glucagon gene expression or glucagon secretion. Our studies demonstrate a link between HMGN3 and glucagon blood levels that is not directly dependent of the function of pancreatic alpha-cells.
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Affiliation(s)
- Toshihiro Kurahashi
- Protein Section, Laboratory of Metabolism, Cancer Research, National Cancer Institute, NIH, Bethesda, Maryland 20892, USA
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15
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The nucleosome binding protein HMGN3 modulates the transcription profile of pancreatic beta cells and affects insulin secretion. Mol Cell Biol 2009; 29:5264-76. [PMID: 19651901 DOI: 10.1128/mcb.00526-09] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Improper glucose-stimulated insulin secretion from pancreatic beta cells is a major factor in the onset of type 2 diabetes. We now report that HMGN3, a nuclear protein that binds to nucleosomes and affects chromatin function, is highly expressed in beta cells and that in mice, loss of HMGN3 impairs glucose-stimulated insulin secretion and leads to a diabetic phenotype. In pancreatic beta cells, loss of HMGN3 affects the transcription of several genes involved in glucose-stimulated insulin secretion, including that of the Glut2 glucose transporter. Chromatin immunoprecipitation reveals that HMGN3 and the transcription factor PDX1 mutually reinforce their specific binding to the chromatin in the promoter of the Glut2 gene, thereby regulating GLUT2 protein levels in pancreatic islets and in beta cells. Our results identify a new regulator of glucose homeostasis and demonstrate a link between the activity of a nucleosome binding structural protein and the regulation of insulin secretion.
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16
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Nissom PM, Sanny A, Kok YJ, Hiang YT, Chuah SH, Shing TK, Lee YY, Wong KTK, Hu WS, Sim MYG, Philp R. Transcriptome and proteome profiling to understanding the biology of high productivity CHO cells. Mol Biotechnol 2007; 34:125-40. [PMID: 17172658 DOI: 10.1385/mb:34:2:125] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/1999] [Revised: 11/30/1999] [Accepted: 11/30/1999] [Indexed: 12/23/2022]
Abstract
A combined transcriptome and proteome analysis was carried out to identify key genes and proteins differentially expressed in Chinese hamster ovary (CHO) cells producing high and low levels of dhfr-GFP fusion protein. Comparison of transcript levels was performed using a proprietary 15K CHO cDNA microarray chip, whereas proteomic analysis was performed using iTRAQ quantitative protein profiling technique. Microarray analysis revealed 77 differentially expressed genes, with 53 genes upregulated and 24 genes downregulated. Proteomic analysis gave 75 and 80 proteins for the midexponential and stationary phase, respectively. Although there was a general lack of correlation between mRNA levels and quantitated protein abundance, results from both datasets concurred on groups of proteins/genes based on functional categorization. A number of genes (20%) and proteins (45 and 23%) were involved in processes related to protein biosynthesis. We also identified three genes/proteins involved in chromatin modification. Enzymes responsible for opening up chromatin, Hmgn3 and Hmgb1, were upregulated whereas enzymes that condense chromatin, histone H1.2, were downregulated. Genes and proteins that promote cell growth (Igfbp4, Ptma, S100a6, and Lgals3) were downregulated, whereas those that deter cell growth (Ccng2, Gsg2, and S100a11) were upregulated. Other main groups of genes and proteins include carbohydrate metabolism, signal transduction, and transport. Our findings show that an integrated genomic and proteomics approach can be effectively utilized to monitor transcriptional and posttranscriptional events of mammalian cells in culture.
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Affiliation(s)
- Peter Morin Nissom
- Bioprocessing Technology Institute, 20 Biopolis Way, #06-01 Centros, Singapore, 138668.
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17
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Plaschkes I, Silverman FW, Priel E. DNA topoisomerase I in the mouse central nervous system: Age and sex dependence. J Comp Neurol 2006; 493:357-69. [PMID: 16261531 DOI: 10.1002/cne.20793] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Topoisomerase I (topo I) is a nuclear enzyme responsible for the topological state of DNA and therefore participates in most DNA transactions, particularly in transcription. Topo I, a ubiquitous enzyme, was identified and characterized in various cell types and tissues; however, the characterization of topo I in the intact central nervous system was not performed. Here we investigated, for the first time, the activity, level, and distribution pattern of topo I in the various selected brain regions in the mouse. In the visual cortex, cerebellum, and striatum the activity of topo I was 3-4-fold higher compared to that found in the hippocampus and hypothalamus. Immunohistochemical and immunofluorescence analyses revealed specific distribution patterns of topo I protein in neurons of each of the areas examined. The highest topo I levels were observed in inhibitory neurons. In addition to the expected nuclear localization of this protein, some neurons exhibited significant cytoplasmic content as well. The activity and level of topo I is age- and gender-dependent. It increases from birth to maturity and decreases, more significantly in males, with senescence. These results point to a possible importance and involvement of topo I activity and regulation in various brain functions.
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Affiliation(s)
- Inbar Plaschkes
- Department of Microbiology & Immunology, the Ben-Gurion University Cancer Research Center, Beer-Sheva 84105, Israel
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18
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West KL, Castellini MA, Duncan MK, Bustin M. Chromosomal proteins HMGN3a and HMGN3b regulate the expression of glycine transporter 1. Mol Cell Biol 2004; 24:3747-56. [PMID: 15082770 PMCID: PMC387732 DOI: 10.1128/mcb.24.9.3747-3756.2004] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
HMGN proteins promote chromatin unfolding, enhance access to nucleosomes, and modulate transcription from chromatin templates. It is not known whether they act indiscriminately as general modulators of transcription or whether they regulate specific gene expression. Here, we investigated the role of HMGN3, a recently discovered HMGN family member, in transcription in vivo. We created cell lines overexpressing HMGN3a or its splice variant, HMGN3b, and analyzed their gene expression profiles using microarrays and reverse transcriptase PCR. We found that ectopic expression of HMGN3a alters the expression of approximately 0.8% of genes. Both HMGN3a and HMGN3b upregulate the expression of the glycine transporter 1 gene (Glyt1). Glyt1 encodes a membrane transporter that regulates the glycine concentration in synaptic junctions. Both GLYT1 and HMGN3 are highly expressed in glia cells and the eye, and we show that both proteins are coexpressed in the retina. Chromatin immunoprecipitation assays showed that HMGN3 protein is recruited to a region of the Glyt1 gene encompassing the Glyt1a transcriptional start site. These results suggest that HMGN3 regulates Glyt1 expression and demonstrate that members of the HMGN family can regulate the transcription of specific genes.
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Affiliation(s)
- Katherine L West
- Division of Cancer Sciences and Molecular Pathology, University of Glasgow, Glasgow, United Kingdom.
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