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Saab C, Stephan J, Akoury E. Structural insights into the binding mechanism of Clr4 methyltransferase to H3K9 methylated nucleosome. Sci Rep 2024; 14:5438. [PMID: 38443490 PMCID: PMC10914790 DOI: 10.1038/s41598-024-56248-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Accepted: 03/04/2024] [Indexed: 03/07/2024] Open
Abstract
The establishment and maintenance of heterochromatin, a specific chromatin structure essential for genomic stability and regulation, rely on intricate interactions between chromatin-modifying enzymes and nucleosomal histone proteins. However, the precise trigger for these modifications remains unclear, thus highlighting the need for a deeper understanding of how methyltransferases facilitate histone methylation among others. Here, we investigate the molecular mechanisms underlying heterochromatin assembly by studying the interaction between the H3K9 methyltransferase Clr4 and H3K9-methylated nucleosomes. Using a combination of liquid-state nuclear magnetic resonance spectroscopy and cryo-electron microscopy, we elucidate the structural basis of Clr4 binding to H3K9-methylated nucleosomes. Our results reveal that Clr4 engages with nucleosomes through its chromodomain and disordered regions to promote de novo methylation. This study provides crucial insights into the molecular mechanisms governing heterochromatin formation by highlighting the significance of chromatin-modifying enzymes in genome regulation and disease pathology.
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Affiliation(s)
- Christopher Saab
- Department of Natural Sciences, Lebanese American University, Beirut, 1102-2801, Lebanon
- Department of Chemistry, McGill University, 801 Sherbrooke St. West, Montreal, QC, H3AOB8, Canada
| | - Joseph Stephan
- School of Medicine, Lebanese American University, PO Box 36, Byblos, Lebanon
| | - Elias Akoury
- Department of Natural Sciences, Lebanese American University, Beirut, 1102-2801, Lebanon.
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Sengupta D, Sengupta K. Lamin A K97E leads to NF-κB-mediated dysfunction of inflammatory responses in dilated cardiomyopathy. Biol Cell 2024; 116:e2300094. [PMID: 38404031 DOI: 10.1111/boc.202300094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 12/07/2023] [Accepted: 01/04/2024] [Indexed: 02/27/2024]
Abstract
BACKGROUND INFORMATION Lamins are type V intermediate filament proteins underlying the inner nuclear membrane which provide structural rigidity to the nucleus, tether the chromosomes, maintain nuclear homeostasis, and remain dynamically associated with developmentally regulated regions of the genome. A large number of mutations particularly in the LMNA gene encoding lamin A/C results in a wide array of human diseases, collectively termed as laminopathies. Dilated Cardiomyopathy (DCM) is one such laminopathic cardiovascular disease which is associated with systolic dysfunction of left or both ventricles leading to cardiac arrhythmia which ultimately culminates into myocardial infarction. RESULTS In this work, we have unraveled the epigenetic landscape to address the regulation of gene expression in mouse myoblast cell line in the context of the missense mutation LMNA 289A CONCLUSIONS We report here for the first time that there is a significant downregulation of the NF-κB pathway, which has been implicated in cardio-protection elsewhere. SIGNIFICANCE This provides a new pathophysiological explanation that correlates an LMNA mutation and dilated cardiomyopathy.
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Affiliation(s)
- Duhita Sengupta
- Biophysics and Structural Genomics Division, Saha Institute of Nuclear Physics, Kolkata, India
- Homi Bhabha National Institute (HBNI), Mumbai, India
| | - Kaushik Sengupta
- Biophysics and Structural Genomics Division, Saha Institute of Nuclear Physics, Kolkata, India
- Homi Bhabha National Institute (HBNI), Mumbai, India
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Zhang H, Zhang T, Wan X, Chen C, Wang S, Qin D, Li L, Yu L, Wu X. LSM14B coordinates protein component expression in the P-body and controls oocyte maturation. J Genet Genomics 2024; 51:48-60. [PMID: 37481122 DOI: 10.1016/j.jgg.2023.07.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 07/13/2023] [Accepted: 07/14/2023] [Indexed: 07/24/2023]
Abstract
The generation of mature and healthy oocytes is the most critical event in the entire female reproductive process, and the mechanisms regulating this process remain to be studied. Here, we demonstrate that Smith-like (LSM) family member 14B (LSM14B) regulates oocyte maturation, and the loss of LSM14B in mouse ovaries leads to abnormal oocyte MII arrest and female infertility. Next, we find the aberrant transcriptional activation, indicated by abnormal non-surrounded nucleolus and surrounded nucleolus oocyte proportions, and abnormal chromosome assembly and segregation in Lsm14b-deficient mouse oocytes. The global transcriptome analysis suggests that many transcripts involved in cytoplasmic processing body (P-body) function are altered in Lsm14b-deficient mouse oocytes. Deletion of Lsm14b results in the expression and/or localization changes of P-body components (such as LSM14A, DCP1A, and 4E-T). Notably, DDX6, a key component of the P-body, is downregulated and accumulates in the nuclei in Lsm14b-deficient mouse oocytes. Taken together, our data suggest that LSM14B links mouse oocyte maturation to female fertility through the regulation of the P-body.
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Affiliation(s)
- Huiru Zhang
- State Key Laboratory of Reproductive Medicine and Offspring Health, Nanjing Medical University, Nanjing, Jiangsu 210029, China
| | - Tao Zhang
- State Key Laboratory of Reproductive Medicine and Offspring Health, Nanjing Medical University, Nanjing, Jiangsu 210029, China
| | - Xiang Wan
- State Key Laboratory of Reproductive Medicine and Offspring Health, Nanjing Medical University, Nanjing, Jiangsu 210029, China
| | - Chang Chen
- State Key Laboratory of Reproductive Medicine and Offspring Health, Nanjing Medical University, Nanjing, Jiangsu 210029, China
| | - Shu Wang
- State Key Laboratory of Reproductive Medicine and Offspring Health, Nanjing Medical University, Nanjing, Jiangsu 210029, China
| | - Dongdong Qin
- State Key Laboratory of Reproductive Medicine and Offspring Health, Nanjing Medical University, Nanjing, Jiangsu 210029, China
| | - Lufan Li
- State Key Laboratory of Reproductive Medicine and Offspring Health, Nanjing Medical University, Nanjing, Jiangsu 210029, China
| | - Luping Yu
- Center for Reproductive Medicine and Obstetrics and Gynecology, Nanjing Drum Tower Hospital, Nanjing University Medical School, Nanjing, Jiangsu 210029, China.
| | - Xin Wu
- State Key Laboratory of Reproductive Medicine and Offspring Health, Nanjing Medical University, Nanjing, Jiangsu 210029, China.
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Liu H, Marayati BF, de la Cerda D, Lemezis BM, Gao J, Song Q, Chen M, Reid KZ. The Cross-Regulation Between Set1, Clr4, and Lsd1/2 in Schizosaccharomyces pombe. PLoS Genet 2024; 20:e1011107. [PMID: 38181050 PMCID: PMC10795994 DOI: 10.1371/journal.pgen.1011107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 01/18/2024] [Accepted: 12/12/2023] [Indexed: 01/07/2024] Open
Abstract
Eukaryotic chromatin is organized into either silenced heterochromatin or relaxed euchromatin regions, which controls the accessibility of transcriptional machinery and thus regulates gene expression. In fission yeast, Schizosaccharomyces pombe, Set1 is the sole H3K4 methyltransferase and is mainly enriched at the promoters of actively transcribed genes. In contrast, Clr4 methyltransferase initiates H3K9 methylation, which has long been regarded as a hallmark of heterochromatic silencing. Lsd1 and Lsd2 are two highly conserved H3K4 and H3K9 demethylases. As these histone-modifying enzymes perform critical roles in maintaining histone methylation patterns and, consequently, gene expression profiles, cross-regulations among these enzymes are part of the complex regulatory networks. Thus, elucidating the mechanisms that govern their signaling and mutual regulations remains crucial. Here, we demonstrated that C-terminal truncation mutants, lsd1-ΔHMG and lsd2-ΔC, do not compromise the integrity of the Lsd1/2 complex but impair their chromatin-binding capacity at the promoter region of target genomic loci. We identified protein-protein interactions between Lsd1/2 and Raf2 or Swd2, which are the subunits of the Clr4 complex (CLRC) and Set1-associated complex (COMPASS), respectively. We showed that Clr4 and Set1 modulate the protein levels of Lsd1 and Lsd2 in opposite ways through the ubiquitin-proteasome-dependent pathway. During heat stress, the protein levels of Lsd1 and Lsd2 are upregulated in a Set1-dependent manner. The increase in protein levels is crucial for differential gene expression under stress conditions. Together, our results support a cross-regulatory model by which Set1 and Clr4 methyltransferases control the protein levels of Lsd1/2 demethylases to shape the dynamic chromatin landscape.
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Affiliation(s)
- Haoran Liu
- Department of Biology, Wake Forest University, Winston-Salem, North Carolina, United States of America
| | - Bahjat Fadi Marayati
- Department of Biochemistry, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - David de la Cerda
- Department of Biology, Wake Forest University, Winston-Salem, North Carolina, United States of America
| | - Brendan Matthew Lemezis
- Department of Biology, Wake Forest University, Winston-Salem, North Carolina, United States of America
| | - Jieyu Gao
- Department of Biology, Wake Forest University, Winston-Salem, North Carolina, United States of America
| | - Qianqian Song
- Department of Health Outcomes and Biomedical Informatics, University of Florida, Gainesville, Florida, United States of America
| | - Minghan Chen
- Department of Computer Science, Wake Forest University, Winston-Salem, North Carolina, United States of America
| | - Ke Zhang Reid
- Department of Biology, Wake Forest University, Winston-Salem, North Carolina, United States of America
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Rahayu AF, Hayashi A, Yoshimura Y, Nakagawa R, Arita K, Nakayama JI. Cooperative DNA-binding activities of Chp2 are critical for its function in heterochromatin assembly. J Biochem 2023; 174:371-382. [PMID: 37400983 DOI: 10.1093/jb/mvad050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 06/27/2023] [Accepted: 06/28/2023] [Indexed: 07/05/2023] Open
Abstract
Heterochromatin protein 1 (HP1) is an evolutionarily conserved protein that plays a critical role in heterochromatin assembly. HP1 proteins share a basic structure consisting of an N-terminal chromodomain (CD) and a C-terminal chromoshadow domain (CSD) linked by a disordered hinge region. The CD recognizes histone H3 lysine 9 methylation, a hallmark of heterochromatin, while the CSD forms a dimer to recruit other chromosomal proteins. HP1 proteins have been shown to bind DNA or RNA primarily through the hinge region. However, how DNA or RNA binding contributes to their function remains elusive. Here, we focus on Chp2, one of the two HP1 proteins in fission yeast, and investigate how Chp2's DNA-binding ability contributes to its function. Similar to other HP1 proteins, the Chp2 hinge exhibits clear DNA-binding activity. Interestingly, the Chp2 CSD also shows robust DNA-binding activity. Mutational analysis revealed that basic residues in the Chp2 hinge and at the N-terminus of the CSD are essential for DNA binding, and the combined amino acid substitutions of these residues alter Chp2 stability, impair Chp2 heterochromatin localization and lead to a silencing defect. These results demonstrate that the cooperative DNA-binding activities of Chp2 play an important role in heterochromatin assembly in fission yeast.
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Affiliation(s)
- Anisa Fitri Rahayu
- Division of Chromatin Regulation, National Institute for Basic Biology, 38 Nishigonaka, Myodaiji, Okazaki 444-8585, Japan
- Department of Basic Biology, School of Life Science, The Graduate University for Advanced Studies, SOKENDAI, 38 Nishigonaka, Myodaiji, Okazaki 444-8585, Japan
| | - Aki Hayashi
- Division of Chromatin Regulation, National Institute for Basic Biology, 38 Nishigonaka, Myodaiji, Okazaki 444-8585, Japan
| | - Yuriko Yoshimura
- Division of Chromatin Regulation, National Institute for Basic Biology, 38 Nishigonaka, Myodaiji, Okazaki 444-8585, Japan
| | - Reiko Nakagawa
- Laboratory for Cell-Free Protein Synthesis, RIKEN Center for Biosystems Dynamics Research, 6-7-1 Minatojima-minamimachi, Chuo-ku, Kobe 650-0047, Japan
| | - Kyohei Arita
- Graduate School of Medical Life Science, Yokohama City University, 1-7-29, Suehiro-cho, Tsurumi-ku, Kanagawa 230-0045, Japan
| | - Jun-Ichi Nakayama
- Division of Chromatin Regulation, National Institute for Basic Biology, 38 Nishigonaka, Myodaiji, Okazaki 444-8585, Japan
- Department of Basic Biology, School of Life Science, The Graduate University for Advanced Studies, SOKENDAI, 38 Nishigonaka, Myodaiji, Okazaki 444-8585, Japan
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Allele-specific aberration of imprinted domain chromosome architecture associates with large offspring syndrome. iScience 2022; 25:104269. [PMID: 35542046 PMCID: PMC9079005 DOI: 10.1016/j.isci.2022.104269] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 03/12/2022] [Accepted: 04/13/2022] [Indexed: 11/21/2022] Open
Abstract
Large offspring syndrome (LOS) and Beckwith-Wiedemann syndrome are similar epigenetic congenital overgrowth conditions in ruminants and humans, respectively. We have reported global loss-of-imprinting, methylome epimutations, and gene misregulation in LOS. However, less than 4% of gene misregulation can be explained with short range (<20kb) alterations in DNA methylation. Therefore, we hypothesized that methylome epimutations in LOS affect chromosome architecture which results in misregulation of genes located at distances >20kb in cis and in trans (other chromosomes). Our analyses focused on two imprinted domains that frequently reveal misregulation in these syndromes, namely KvDMR1 and IGF2R. Using bovine fetal fibroblasts, we identified CTCF binding at IGF2R imprinting control region but not KvDMR1, and allele-specific chromosome architecture of these domains in controls. In LOS, analyses identified erroneous long-range contacts and clustering tendency in the direction of expression of misregulated genes. In conclusion, altered chromosome architecture is associated with LOS. IGF2R imprinted domain has allele-specific chromosome architecture in bovines In bovines, CTCF binds at IGF2R imprinting control region but not at KvDMR1 Bovine large offspring syndrome (LOS) shows altered chromosome architecture at IGF2R Misregulated genes in LOS exhibit genomic location-based clustering tendency
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Llorens-Giralt P, Camilleri-Robles C, Corominas M, Climent-Cantó P. Chromatin Organization and Function in Drosophila. Cells 2021; 10:cells10092362. [PMID: 34572010 PMCID: PMC8465611 DOI: 10.3390/cells10092362] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 09/03/2021] [Accepted: 09/06/2021] [Indexed: 12/25/2022] Open
Abstract
Eukaryotic genomes are packaged into high-order chromatin structures organized in discrete territories inside the cell nucleus, which is surrounded by the nuclear envelope acting as a barrier. This chromatin organization is complex and dynamic and, thus, determining the spatial and temporal distribution and folding of chromosomes within the nucleus is critical for understanding the role of chromatin topology in genome function. Primarily focusing on the regulation of gene expression, we review here how the genome of Drosophila melanogaster is organized into the cell nucleus, from small scale histone–DNA interactions to chromosome and lamina interactions in the nuclear space.
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Hartman C, Legoff L, Capriati M, Lecuyer G, Kernanec PY, Tevosian S, D'Cruz SC, Smagulova F. Epigenetic Effects Promoted by Neonicotinoid Thiacloprid Exposure. Front Cell Dev Biol 2021; 9:691060. [PMID: 34295895 PMCID: PMC8290843 DOI: 10.3389/fcell.2021.691060] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Accepted: 06/03/2021] [Indexed: 12/31/2022] Open
Abstract
Background Neonicotinoids, a widely used class of insecticide, have attracted much attention because of their widespread use that has resulted in the decline of the bee population. Accumulating evidence suggests potential animal and human exposure to neonicotinoids, which is a cause of public concern. Objectives In this study, we examined the effects of a neonicotinoid, thiacloprid (thia), on the male reproductive system. Methods The pregnant outbred Swiss female mice were exposed to thia at embryonic days E6.5 to E15.5 using “0,” “0.06,” “0.6,” and “6” mg/kg/day doses. Adult male progeny was analyzed for morphological and cytological defects in the testes using hematoxylin and eosin (H&E) staining. We also used immunofluorescence, Western blotting, RT-qPCR and RNA-seq techniques for the analyses of the effects of thia on testis. Results We found that exposure to thia causes a decrease in spermatozoa at doses “0.6” and “6” and leads to telomere defects at all tested doses. At doses “0.6” and “6,” thia exposure leads to an increase in meiotic pachytene cells and a decrease in lumen size, these changes were accompanied by increased testis-to-body weight ratios at high dose. By using RNA-seq approach we found that genes encoding translation, ATP production, ATP-dependent proteins and chromatin-modifying enzymes were deregulated in testes. In addition, we found that exposure to thia results in a decrease in H3K9me3 levels in spermatocytes. The changes in H3K9me3 were associated with a dramatic increase in activity of retroelements. Conclusion Our study suggests that gestational exposure to thia affects epigenetic mechanisms controlling meiosis which could lead to deleterious effects on male spermatogenesis.
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Affiliation(s)
- Colin Hartman
- EHESP, Inserm, Institut de Recherche en Santé, Environnement et Travail - UMR_S 1085, Université de Rennes 1, Rennes, France
| | - Louis Legoff
- EHESP, Inserm, Institut de Recherche en Santé, Environnement et Travail - UMR_S 1085, Université de Rennes 1, Rennes, France
| | - Martina Capriati
- EHESP, Inserm, Institut de Recherche en Santé, Environnement et Travail - UMR_S 1085, Université de Rennes 1, Rennes, France
| | - Gwendoline Lecuyer
- EHESP, Inserm, Institut de Recherche en Santé, Environnement et Travail - UMR_S 1085, Université de Rennes 1, Rennes, France
| | - Pierre-Yves Kernanec
- EHESP, Inserm, Institut de Recherche en Santé, Environnement et Travail - UMR_S 1085, Université de Rennes 1, Rennes, France
| | - Sergei Tevosian
- Department of Physiological Sciences, University of Florida, Gainesville, FL, United States
| | - Shereen Cynthia D'Cruz
- EHESP, Inserm, Institut de Recherche en Santé, Environnement et Travail - UMR_S 1085, Université de Rennes 1, Rennes, France
| | - Fatima Smagulova
- EHESP, Inserm, Institut de Recherche en Santé, Environnement et Travail - UMR_S 1085, Université de Rennes 1, Rennes, France
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Mechanism of the Conformational Change of the Protein Methyltransferase SMYD3: A Molecular Dynamics Simulation Study. Int J Mol Sci 2021; 22:ijms22137185. [PMID: 34281237 PMCID: PMC8267938 DOI: 10.3390/ijms22137185] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 06/26/2021] [Accepted: 06/29/2021] [Indexed: 12/30/2022] Open
Abstract
SMYD3 is a SET-domain-containing methyltransferase that catalyzes the transfer of methyl groups onto lysine residues of substrate proteins. Methylation of MAP3K2 by SMYD3 has been implicated in Ras-driven tumorigenesis, which makes SMYD3 a potential target for cancer therapy. Of all SMYD family proteins, SMYD3 adopt a closed conformation in a crystal structure. Several studies have suggested that the conformational changes between the open and closed forms may regulate the catalytic activity of SMYD3. In this work, we carried out extensive molecular dynamics simulations on a series of complexes with a total of 21 μs sampling to investigate the conformational changes of SMYD3 and unveil the molecular mechanisms. Based on the C-terminal domain movements, the simulated models could be depicted in three different conformational states: the closed, intermediate and open states. Only in the case that both the methyl donor binding pocket and the target lysine-binding channel had bound species did the simulations show SMYD3 maintaining its conformation in the closed state, indicative of a synergetic effect of the cofactors and target lysine on regulating the conformational change of SMYD3. In addition, we performed analyses in terms of structure and energy to shed light on how the two regions might regulate the C-terminal domain movement. This mechanistic study provided insights into the relationship between the conformational change and the methyltransferase activity of SMYD3. The more complete understanding of the conformational dynamics developed here together with further work may lay a foundation for the rational drug design of SMYD3 inhibitors.
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Copy number-dependent DNA methylation of the Pyricularia oryzae MAGGY retrotransposon is triggered by DNA damage. Commun Biol 2021; 4:351. [PMID: 33742058 PMCID: PMC7979813 DOI: 10.1038/s42003-021-01836-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Accepted: 02/11/2021] [Indexed: 11/08/2022] Open
Abstract
Transposable elements are common targets for transcriptional and post-transcriptional gene silencing in eukaryotic genomes. However, the molecular mechanisms responsible for sensing such repeated sequences in the genome remain largely unknown. Here, we show that machinery of homologous recombination (HR) and RNA silencing play cooperative roles in copy number-dependent de novo DNA methylation of the retrotransposon MAGGY in the fungus Pyricularia oryzae. Genetic and physical interaction studies revealed that RecA domain-containing proteins, including P. oryzae homologs of Rad51, Rad55, and Rad57, together with an uncharacterized protein, Ddnm1, form complex(es) and mediate either the overall level or the copy number-dependence of de novo MAGGY DNA methylation, likely in conjunction with DNA repair. Interestingly, P. oryzae mutants of specific RNA silencing components (MoDCL1 and MoAGO2) were impaired in copy number-dependence of MAGGY methylation. Co-immunoprecipitation of MoAGO2 and HR components suggested a physical interaction between the HR and RNA silencing machinery in the process.
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Jan S, Dar MI, Wani R, Sandey J, Mushtaq I, Lateef S, Syed SH. Targeting EHMT2/ G9a for cancer therapy: Progress and perspective. Eur J Pharmacol 2020; 893:173827. [PMID: 33347828 DOI: 10.1016/j.ejphar.2020.173827] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Revised: 12/12/2020] [Accepted: 12/16/2020] [Indexed: 12/11/2022]
Abstract
Euchromatic histone lysine methyltransferase-2, also known as G9a, is a ubiquitously expressed SET domain-containing histone lysine methyltransferase linked with both facultative and constitutive heterochromatin formation and transcriptional repression. It is an essential developmental gene and reported to play role in embryonic development, establishment of proviral silencing in ES cells, tumor cell growth, metastasis, T-cell immune response, cocaine induced neural plasticity and cognition and adaptive behavior. It is mainly responsible for carrying out mono, di and tri methylation of histone H3K9 in euchromatin. G9a levels are elevated in many cancers and its selective inhibition is known to reduce the cell growth and induce autophagy, apoptosis and senescence. We carried out a thorough search of online literature databases including Pubmed, Scopus, Journal websites, Clinical trials etc to gather the maximum possible information related to the G9a. The main messages from the cited papers are presented in a systematic manner. Chemical structures were drawn by Chemdraw software. In this review, we shed light on current understanding of structure and biological activity of G9a, the molecular events directing its targeting to genomic regions and its post-translational modification. Finally, we discuss the current strategies to target G9a in different cancers and evaluate the available compounds and agents used to inhibit G9a functions. The review provides the present status and future directions of research in targeting G9a and provides the basis to persuade the development of novel strategies to target G9a -related effects in cancer cells.
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Affiliation(s)
- Suraya Jan
- CSIR, Indian Institute of Integrative Medicine, Sanatnagar, 190005, Srinagar, Kashmir, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Mohd Ishaq Dar
- CSIR, Indian Institute of Integrative Medicine, Sanatnagar, 190005, Srinagar, Kashmir, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Rubiada Wani
- CSIR, Indian Institute of Integrative Medicine, Sanatnagar, 190005, Srinagar, Kashmir, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Jagjeet Sandey
- CSIR, Indian Institute of Integrative Medicine, Sanatnagar, 190005, Srinagar, Kashmir, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Iqra Mushtaq
- CSIR, Indian Institute of Integrative Medicine, Sanatnagar, 190005, Srinagar, Kashmir, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Sammar Lateef
- CSIR, Indian Institute of Integrative Medicine, Sanatnagar, 190005, Srinagar, Kashmir, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Sajad Hussain Syed
- CSIR, Indian Institute of Integrative Medicine, Sanatnagar, 190005, Srinagar, Kashmir, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India.
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Takayama Y. Identification of Genes Encoding CENP-A and Heterochromatin Protein 1 of Lipomyces starkeyi and Functional Analysis Using Schizosaccharomyces pombe. Genes (Basel) 2020; 11:genes11070769. [PMID: 32650514 PMCID: PMC7397231 DOI: 10.3390/genes11070769] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 07/06/2020] [Accepted: 07/06/2020] [Indexed: 11/16/2022] Open
Abstract
Centromeres function as a platform for the assembly of multiple kinetochore proteins and are essential for chromosome segregation. An active centromere is characterized by the presence of a centromere-specific histone H3 variant, CENP-A. Faithful centromeric localization of CENP-A is supported by heterochromatin in almost all eukaryotes; however, heterochromatin proteins have been lost in most Saccharomycotina. Here, identification of CENP-A (CENP-AL.s.) and heterochromatin protein 1 (Lsw1) in a Saccharomycotina species, the oleaginous yeast Lipomyces starkeyi, is reported. To determine if these proteins are functional, the proteins in S. pombe, a species widely used to study centromeres, were ectopically expressed. CENP-AL.s. localizes to centromeres and can be replaced with S. pombe CENP-A, indicating that CENP-AL.s. is a functional centromere-specific protein. Lsw1 binds at heterochromatin regions, and chromatin binding is dependent on methylation of histone H3 at lysine 9. In other species, self-interaction of heterochromatin protein 1 is thought to cause folding of chromatin, triggering transcription repression and heterochromatin formation. Consistent with this, it was found that Lsw1 can self-interact. L. starkeyi chromatin contains the methylation of histone H3 at lysine 9. These results indicated that L. starkeyi has a primitive heterochromatin structure and is an attractive model for analysis of centromere heterochromatin evolution.
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Affiliation(s)
- Yuko Takayama
- Department of Biosciences, School of Science and Engineering, Teikyo University, 1-1 Toyosatodai, Utsunomiya, Tochigi 320–8551, Japan; ; Tel.: +81-28-627-7242
- Division of Integrated Science and Engineering, Graduate School of Science and Engineering, Teikyo University Graduate Schools, 1–1 Toyosatodai, Utsunomiya, Tochigi 320–8551, Japan
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Abo1 is required for the H3K9me2 to H3K9me3 transition in heterochromatin. Sci Rep 2020; 10:6055. [PMID: 32269268 PMCID: PMC7142091 DOI: 10.1038/s41598-020-63209-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Accepted: 03/26/2020] [Indexed: 01/24/2023] Open
Abstract
Heterochromatin regulation is critical for genomic stability. Different H3K9 methylation states have been discovered, with distinct roles in heterochromatin formation and silencing. However, how the transition from H3K9me2 to H3K9me3 is controlled is still unclear. Here, we investigate the role of the conserved bromodomain AAA-ATPase, Abo1, involved in maintaining global nucleosome organisation in fission yeast. We identified several key factors involved in heterochromatin silencing that interact genetically with Abo1: histone deacetylase Clr3, H3K9 methyltransferase Clr4, and HP1 homolog Swi6. Cells lacking Abo1 cultivated at 30 °C exhibit an imbalance of H3K9me2 and H3K9me3 in heterochromatin. In abo1∆ cells, the centromeric constitutive heterochromatin has increased H3K9me2 but decreased H3K9me3 levels compared to wild-type. In contrast, facultative heterochromatin regions exhibit reduced H3K9me2 and H3K9me3 levels in abo1∆. Genome-wide analysis showed that abo1∆ cells have silencing defects in both the centromeres and subtelomeres, but not in a subset of heterochromatin islands in our condition. Thus, our work uncovers a role of Abo1 in stabilising directly or indirectly Clr4 recruitment to allow the H3K9me2 to H3K9me3 transition in heterochromatin.
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Streptonigrin at low concentration promotes heterochromatin formation. Sci Rep 2020; 10:3478. [PMID: 32103104 PMCID: PMC7044429 DOI: 10.1038/s41598-020-60469-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Accepted: 02/04/2020] [Indexed: 11/26/2022] Open
Abstract
Heterochromatin is essential for regulating global gene transcription and protecting genome stability, and may play a role in tumor suppression. Drugs promoting heterochromatin are potential cancer therapeutics but very few are known. In order to identify drugs that can promote heterochromatin, we used a cell-based method and screened NCI drug libraries consisting of oncology drugs and natural compounds. Since heterochromatin is originally defined as intensely stained chromatin in the nucleus, we estimated heterochromatin contents of cells treated with different drugs by quantifying the fluorescence intensity of nuclei stained with Hoechst DNA dye. We used HeLa cells and screened 231 FDA-approved oncology and natural substance drugs included in two NCI drug libraries representing a variety of chemical structures. Among these drugs, streptonigrin most prominently caused an increase in Hoechst-stained nuclear fluorescence intensity. We further show that streptonigrin treated cells exhibit compacted DNA foci in the nucleus that co-localize with Heterochromatin Protein 1 alpha (HP1α), and exhibit an increase in total levels of the heterochromatin mark, H3K9me3. Interestingly, we found that streptonigrin promotes heterochromatin at a concentration as low as one nanomolar, and at this concentration there were no detectable effects on cell proliferation or viability. Finally, in line with a previous report, we found that streptonigrin inhibits STAT3 phosphorylation, raising the possibility that non-canonical STAT function may contribute to the effects of streptonigrin on heterochromatin. These results suggest that, at low concentrations, streptonigrin may primarily enhance heterochromatin formation with little toxic effects on cells, and therefore might be a good candidate for epigenetic cancer therapy.
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15
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Dutta P, Zhang L, Zhang H, Peng Q, Montgrain PR, Wang Y, Song Y, Li J, Li WX. Unphosphorylated STAT3 in heterochromatin formation and tumor suppression in lung cancer. BMC Cancer 2020; 20:145. [PMID: 32087696 PMCID: PMC7036253 DOI: 10.1186/s12885-020-6649-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Accepted: 02/17/2020] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Aberrant JAK/STAT activation has been detected in many types of human cancers. The role of JAK/STAT activation in cancer has been mostly attributed to direct transcriptional regulation of target genes by phosphorylated STAT (pSTAT), while the unphosphorylated STAT (uSTAT) is believed to be dormant and reside in the cytoplasm. However, several studies have shown that uSTATs can be found in the nucleus. In addition, it has been shown that tissue-specific loss of STAT3 or STAT5 in mice promotes cancer growth in certain tissues, and thus these STAT proteins can act as tumor suppressors. However, no unifying mechanism has been shown for the tumor suppressor function of STATs to date. We have previously demonstrated a non-canonical mode of JAK/STAT signaling for Drosophila STAT and human STAT5A, where a fraction of uSTAT is in the nucleus and associated with Heterochromatin Protein 1 (HP1); STAT activation (by phosphorylation) causes its dispersal, leading to HP1 delocalization and heterochromatin loss. METHODS We used a combination of imaging, cell biological assays, and mouse xenografts to investigate the role of STAT3 in lung cancer development. RESULTS We found that uSTAT3 has a function in promoting heterochromatin formation in lung cancer cells, suppressing cell proliferation in vitro, and suppressing tumor growth in mouse xenografts. CONCLUSIONS Thus, uSTAT3 possesses noncanonical function in promoting heterochromatin formation, and the tumor suppressor function of STAT3 is likely attributable to the heterochromatin-promoting activity of uSTAT3 in the non-canonical JAK/STAT pathway.
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Affiliation(s)
- Pranabananda Dutta
- Department of Medicine, University of California San Diego, La Jolla, CA, 92093, USA
| | - Lin Zhang
- Department of Medicine, University of California San Diego, La Jolla, CA, 92093, USA
| | - Huijun Zhang
- Department of Medicine, University of California San Diego, La Jolla, CA, 92093, USA
- Department of Pulmonary Medicine, Shanghai Respiratory Research Institute, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Qin Peng
- Department of Bioengineering, Institute of Engineering in Medicine, University of California San Diego, La Jolla, CA, 92093, USA
| | - Phillippe R Montgrain
- Department of Medicine, University of California San Diego, La Jolla, CA, 92093, USA
- Veterans Affairs San Diego Healthcare System, San Diego, CA, CA92037, USA
| | - Yingxiao Wang
- Department of Bioengineering, Institute of Engineering in Medicine, University of California San Diego, La Jolla, CA, 92093, USA
| | - Yuanlin Song
- Department of Pulmonary Medicine, Shanghai Respiratory Research Institute, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Jinghong Li
- Department of Medicine, University of California San Diego, La Jolla, CA, 92093, USA.
| | - Willis X Li
- Department of Medicine, University of California San Diego, La Jolla, CA, 92093, USA.
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16
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17
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Pelicci S, Diaspro A, Lanzanò L. Chromatin nanoscale compaction in live cells visualized by acceptor-to-donor ratio corrected Förster resonance energy transfer between DNA dyes. JOURNAL OF BIOPHOTONICS 2019; 12:e201900164. [PMID: 31365191 PMCID: PMC7065635 DOI: 10.1002/jbio.201900164] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 07/14/2019] [Accepted: 07/29/2019] [Indexed: 05/04/2023]
Abstract
@Chromatin nanoscale architecture in live cells can be studied by Förster resonance energy transfer (FRET) between fluorescently labeled chromatin components, such as histones. A higher degree of nanoscale compaction is detected as a higher FRET level, since this corresponds to a higher degree of proximity between donor and acceptor molecules. However, in such a system, the stoichiometry of the donors and acceptors engaged in the FRET process is not well defined and, in principle, FRET variations could be caused by variations in the acceptor-to-donor ratio rather than distance. Here, to get a FRET level independent of the acceptor-to-donor ratio, we combine fluorescence lifetime imaging detection of FRET with a normalization of the FRET level to a pixel-wise estimation of the acceptor-to-donor ratio. We use this method to study FRET between two DNA binding dyes staining the nuclei of live cells. We show that this acceptor-to-donor ratio corrected FRET imaging reveals variations of nanoscale compaction in different chromatin environments. As an application, we monitor the rearrangement of chromatin in response to laser-induced microirradiation and reveal that DNA is rapidly decompacted, at the nanoscale, in response to DNA damage induction.
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Affiliation(s)
- Simone Pelicci
- Nanoscopy and Nikon Imaging Center, Istituto Italiano di TecnologiaGenoaItaly
- Department of PhysicsUniversity of GenoaGenoaItaly
| | - Alberto Diaspro
- Nanoscopy and Nikon Imaging Center, Istituto Italiano di TecnologiaGenoaItaly
- Department of PhysicsUniversity of GenoaGenoaItaly
| | - Luca Lanzanò
- Nanoscopy and Nikon Imaging Center, Istituto Italiano di TecnologiaGenoaItaly
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18
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Sun J, Shi F, Yang N. Exploration of the Substrate Preference of Lysine Methyltransferase SMYD3 by Molecular Dynamics Simulations. ACS OMEGA 2019; 4:19573-19581. [PMID: 31788587 PMCID: PMC6881823 DOI: 10.1021/acsomega.9b01842] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Accepted: 10/31/2019] [Indexed: 06/10/2023]
Abstract
SMYD3, a SET and MYND domain containing lysine methyltransferase, catalyzes the transfer of the methyl group from a methyl donor onto the Nε group of a lysine residue in the substrate protein. Methylation of MAP3 kinase kinase (MAP3K2) by SMYD3 has been implicated in Ras-driven tumorigenesis. The crystal structure of SMYD3 in complex with MAP3K2 peptide reveals a shallow hydrophobic pocket (P-2), which accommodates the binding of a phenylalanine residue at the -2 position of the substrate (F258) is a crucial determinant of substrate specificity of SMYD3. To better understand the substrate preference of SMYD3 at the -2 position, molecular dynamics (MD) simulations and the MM/GBSA method were performed on the crystal structure of SMYD3-MAP3K2 complex (PDB: 5EX0) after substitution of F258 residue of MAP3K2 to each of the other 19 natural residues, respectively. Binding free energy calculations reveal that the P-2 pocket prefers an aromatic hydrophobic group and none of the substitutions behave better than the wild-type phenylalanine residue does. Furthermore, we investigated the structure-activity relationships (SAR) of a series of non-natural phenylalanine derivative substitutions at the -2 position and found that quite a few modifications on the sidechain of F258 residue could strengthen its binding to the P-2 pocket of SMYD3. These explorations provide insights into developing novel SMYD3 inhibitors with high potency and high selectivity against MAP3K2 and cancer.
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Affiliation(s)
| | | | - Na Yang
- E-mail: . Tel/Fax: + 8622 85358193
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19
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Bhattacharjee S, Roche B, Martienssen RA. RNA-induced initiation of transcriptional silencing (RITS) complex structure and function. RNA Biol 2019; 16:1133-1146. [PMID: 31213126 DOI: 10.1080/15476286.2019.1621624] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Heterochromatic regions of the genome are epigenetically regulated to maintain a heritable '"silent state"'. In fission yeast and other organisms, epigenetic silencing is guided by nascent transcripts, which are targeted by the RNA interference pathway. The key effector complex of the RNA interference pathway consists of small interfering RNA molecules (siRNAs) associated with Argonaute, assembled into the RNA-induced transcriptional silencing (RITS) complex. This review focuses on our current understanding of how RITS promotes heterochromatin formation, and in particular on the role of Argonaute-containing complexes in many other functions such as quelling, release of RNA polymerases, cellular quiescence and genome defense.
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Affiliation(s)
- Sonali Bhattacharjee
- a Cold Spring Harbor Laboratory, Howard Hughes Medical Institute , Cold Spring Harbor , NY , USA
| | - Benjamin Roche
- a Cold Spring Harbor Laboratory, Howard Hughes Medical Institute , Cold Spring Harbor , NY , USA
| | - Robert A Martienssen
- a Cold Spring Harbor Laboratory, Howard Hughes Medical Institute , Cold Spring Harbor , NY , USA
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20
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Complex epigenetic regulation of alkaloid biosynthesis and host interaction by heterochromatin protein I in a fungal endophyte-plant symbiosis. Fungal Genet Biol 2019; 125:71-83. [DOI: 10.1016/j.fgb.2019.02.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 01/29/2019] [Accepted: 02/03/2019] [Indexed: 01/10/2023]
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21
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Qiang S, Li FY, Zhou Y, Yuan Y, Li Q. Congenital absence of the penis (aphallia): A rare case report. Medicine (Baltimore) 2019; 98:e15129. [PMID: 30985678 PMCID: PMC6485865 DOI: 10.1097/md.0000000000015129] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 02/25/2019] [Accepted: 03/14/2019] [Indexed: 11/26/2022] Open
Abstract
RATIONALE Absence of the penis, known as aphallia, is a very rare congenital anomaly. It is believed to be a result of either the absence of the genital tubercle or its failure to fully develop and is associated with the level of hormones and chromosomal rearrangements. The failure of the genital tubercle influences the development of the penis and partly depends upon testosterone secreted by Leydig cells of the testis. Chromosomal polymorphisms may affect the functions of protection and regulation, potentially leading to susceptibility to congenital diseases. Herein, an extremely rare case of a congenital absence of the penis is described. PATIENT CONCERNS A 3-month-old was brought to the OPD by his parents with complaints of absence of penis since birth and urine being passed rectally. When he was born, he was registered as a boy because his chromosomes were 46XY but with 9qh+. Local examination revealed the total absence of the penis. The scrotum was well developed. The testes were palpable bilaterally. The anal opening was located normally. No urethral orifice could be identified. However, his parents had not yet decided whether to accept treatment. The child has been lost to follow up. DIAGNOSIS Congenital absence of the penis (aphallia) (46 XY normal male karyotype). INTERVENTIONS We explained the nature of the abnormality and management options to the parents. However, it was much regretted that the patient was too young to make a decision and that his parents had not made a decision yet. They left without any further contact. OUTCOME Because the parents left our hospital without any contact, it has not been possible to develop a follow-up plan. LESSONS In consideration of the rarity and devastating psychosocial consequences of this case, we accordingly call for active cooperation with doctors to minimize the negative impact of this malformation. Early assignment of gender avoids confusion and contradiction. Parental confidence solidifies the child's own confidence in his or her gender.
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22
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Nishibuchi G, Machida S, Nakagawa R, Yoshimura Y, Hiragami-Hamada K, Abe Y, Kurumizaka H, Tagami H, Nakayama JI. Mitotic phosphorylation of HP1α regulates its cell cycle-dependent chromatin binding. J Biochem 2018; 165:433-446. [DOI: 10.1093/jb/mvy117] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 12/14/2018] [Indexed: 11/13/2022] Open
Affiliation(s)
- Gohei Nishibuchi
- Graduate School of Natural Sciences, Nagoya City University, Yamanohata 1, Mizuho-cho, Mizuho-ku, Nagoya, Japan
| | - Shinichi Machida
- Laboratory of Structural Biology, Graduate School of Advanced Science and Engineering, Waseda University, Shinjuku-ku, Tokyo, Japan
| | - Reiko Nakagawa
- Laboratory for Phyloinformatics, RIKEN Center for Biosystems Dynamics Research, 2-2-3 Minatojima-minamimachi, Chuo-ku, Kobe, Japan
| | - Yuriko Yoshimura
- Division of Chromatin Regulation, National Institute for Basic Biology, Nishigonaka 38, Myodaiji, Okazaki, Japan
| | - Kyoko Hiragami-Hamada
- Division of Chromatin Regulation, National Institute for Basic Biology, Nishigonaka 38, Myodaiji, Okazaki, Japan
- Department of Basic Biology, School of Life Science, The Graduate University for Advanced Studies (SOKENDAI), Nishigonaka 38, Myodaiji, Okazaki, Japan
| | - Yusuke Abe
- Division of Experimental Pathology, Cancer Institute of the Japanese Foundation for Cancer Research, Koto-ku, Tokyo, Japan
| | - Hitoshi Kurumizaka
- Laboratory of Structural Biology, Graduate School of Advanced Science and Engineering, Waseda University, Shinjuku-ku, Tokyo, Japan
- Institute for Quantitative Biosciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Hideaki Tagami
- Graduate School of Natural Sciences, Nagoya City University, Yamanohata 1, Mizuho-cho, Mizuho-ku, Nagoya, Japan
| | - Jun-ichi Nakayama
- Graduate School of Natural Sciences, Nagoya City University, Yamanohata 1, Mizuho-cho, Mizuho-ku, Nagoya, Japan
- Division of Chromatin Regulation, National Institute for Basic Biology, Nishigonaka 38, Myodaiji, Okazaki, Japan
- Department of Basic Biology, School of Life Science, The Graduate University for Advanced Studies (SOKENDAI), Nishigonaka 38, Myodaiji, Okazaki, Japan
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23
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NEUROG1 Regulates CDK2 to Promote Proliferation in Otic Progenitors. Stem Cell Reports 2017; 9:1516-1529. [PMID: 29033307 PMCID: PMC5829327 DOI: 10.1016/j.stemcr.2017.09.011] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Revised: 09/13/2017] [Accepted: 09/14/2017] [Indexed: 12/23/2022] Open
Abstract
Loss of spiral ganglion neurons (SGNs) significantly contributes to hearing loss. Otic progenitor cell transplantation is a potential strategy to replace lost SGNs. Understanding how key transcription factors promote SGN differentiation in otic progenitors accelerates efforts for replacement therapies. A pro-neural transcription factor, Neurogenin1 (Neurog1), is essential for SGN development. Using an immortalized multipotent otic progenitor (iMOP) cell line that can self-renew and differentiate into otic neurons, NEUROG1 was enriched at the promoter of cyclin-dependent kinase 2 (Cdk2) and neurogenic differentiation 1 (NeuroD1) genes. Changes in H3K9ac and H3K9me3 deposition at the Cdk2 and NeuroD1 promoters suggested epigenetic regulation during iMOP proliferation and differentiation. In self-renewing iMOP cells, overexpression of NEUROG1 increased CDK2 to drive proliferation, while knockdown of NEUROG1 decreased CDK2 and reduced proliferation. In iMOP-derived neurons, overexpression of NEUROG1 accelerated acquisition of neuronal morphology, while knockdown of NEUROG1 prevented differentiation. Our findings suggest that NEUROG1 can promote proliferation or neuronal differentiation.
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24
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Kidder BL, He R, Wangsa D, Padilla-Nash HM, Bernardo MM, Sheng S, Ried T, Zhao K. SMYD5 Controls Heterochromatin and Chromosome Integrity during Embryonic Stem Cell Differentiation. Cancer Res 2017; 77:6729-6745. [PMID: 28951459 DOI: 10.1158/0008-5472.can-17-0828] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Revised: 08/10/2017] [Accepted: 09/21/2017] [Indexed: 12/18/2022]
Abstract
Epigenetic regulation of chromatin states is thought to control gene expression programs during lineage specification. However, the roles of repressive histone modifications, such as trimethylated histone lysine 20 (H4K20me3), in development and genome stability are largely unknown. Here, we show that depletion of SET and MYND domain-containing protein 5 (SMYD5), which mediates H4K20me3, leads to genome-wide decreases in H4K20me3 and H3K9me3 levels and derepression of endogenous LTR- and LINE-repetitive DNA elements during differentiation of mouse embryonic stem cells. SMYD5 depletion resulted in chromosomal aberrations and the formation of transformed cells that exhibited decreased H4K20me3 and H3K9me3 levels and an expression signature consistent with multiple human cancers. Moreover, dysregulated gene expression in SMYD5 cancer cells was associated with LTR and endogenous retrovirus elements and decreased H4K20me3. In addition, depletion of SMYD5 in human colon and lung cancer cells results in increased tumor growth and upregulation of genes overexpressed in colon and lung cancers, respectively. These findings implicate an important role for SMYD5 in maintaining chromosome integrity by regulating heterochromatin and repressing endogenous repetitive DNA elements during differentiation. Cancer Res; 77(23); 6729-45. ©2017 AACR.
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Affiliation(s)
- Benjamin L Kidder
- Department of Oncology, Wayne State University School of Medicine, Detroit, Michigan. .,Barbara Ann Karmanos Cancer Institute, Wayne State University School of Medicine, Detroit, Michigan
| | - Runsheng He
- Department of Oncology, Wayne State University School of Medicine, Detroit, Michigan.,Barbara Ann Karmanos Cancer Institute, Wayne State University School of Medicine, Detroit, Michigan
| | - Darawalee Wangsa
- Cancer Genomics Section, National Cancer Institute, NIH, Bethesda, Maryland
| | | | - M Margarida Bernardo
- Barbara Ann Karmanos Cancer Institute, Wayne State University School of Medicine, Detroit, Michigan.,Department of Pathology, Wayne State University School of Medicine, Detroit, Michigan
| | - Shijie Sheng
- Barbara Ann Karmanos Cancer Institute, Wayne State University School of Medicine, Detroit, Michigan.,Department of Pathology, Wayne State University School of Medicine, Detroit, Michigan
| | - Thomas Ried
- Cancer Genomics Section, National Cancer Institute, NIH, Bethesda, Maryland
| | - Keji Zhao
- Systems Biology Center, National Heart, Lung and Blood Institute, NIH, Bethesda, Maryland.
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25
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CBX3 promotes colon cancer cell proliferation by CDK6 kinase-independent function during cell cycle. Oncotarget 2017; 8:19934-19946. [PMID: 28193906 PMCID: PMC5386735 DOI: 10.18632/oncotarget.15253] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 12/12/2016] [Indexed: 12/29/2022] Open
Abstract
Heterochromatin protein 1γ (CBX3) links histone methylation marks to transcriptional silence, DNA repair and RNA splicing, but a role for CBX3 in cancer remains largely unknown. In this study, we show that CBX3 in colon cancer cells promotes the progression of the cell cycle and proliferation in vitro and in vivo. Cell cycle (G1 phase to S phase) related gene CDK6 and p21 were further identified as targets of CBX3. In addition, we found that enhancing CDK6 suppresses cell proliferation by upregulating inhibitor p21 in the absence of CBX3, and this function is independent of the kinase activity of CDK6. Our results demonstrate a key role of CBX3 in colon carcinogenesis via suppressing the expression of CDK6/p21, which may disrupt the role of CDK6 in transcriptionally regulating p21, as part of a negative feedback loop to limit CDK6 excessive activation.
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26
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Shirai A, Kawaguchi T, Shimojo H, Muramatsu D, Ishida-Yonetani M, Nishimura Y, Kimura H, Nakayama JI, Shinkai Y. Impact of nucleic acid and methylated H3K9 binding activities of Suv39h1 on its heterochromatin assembly. eLife 2017; 6. [PMID: 28760201 PMCID: PMC5538823 DOI: 10.7554/elife.25317] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2017] [Accepted: 06/07/2017] [Indexed: 12/12/2022] Open
Abstract
SUV39H is the major histone H3 lysine 9 (H3K9)-specific methyltransferase that targets pericentric regions and is crucial for assembling silent heterochromatin. SUV39H recognizes trimethylated H3K9 (H3K9me3) via its chromodomain (CD), and enriched H3K9me3 allows SUV39H to target specific chromosomal regions. However, the detailed targeting mechanisms, especially for naïve chromatin without preexisting H3K9me3, are poorly understood. Here we show that Suv39h1’s CD (Suv39h1-CD) binds nucleic acids, and this binding is important for its function in heterochromatin assembly. Suv39h1-CD had higher binding affinity for RNA than DNA, and its ability to bind nucleic acids was independent of its H3K9me3 recognition. Suv39h1 bound major satellite RNAs in vivo, and knockdown of major satellite RNAs lowered Suv39h1 retention on pericentromere. Suv39h1 mutational studies indicated that both the nucleic acid–binding and H3K9me–binding activities of Suv39h1-CD were crucial for its pericentric heterochromatin assembly. These results suggest that chromatin-bound RNAs contribute to creating SUV39H’s target specificity. DOI:http://dx.doi.org/10.7554/eLife.25317.001 Plants, animals and fungi store much of their DNA tightly packed with proteins in a form named heterochromatin. This arrangement helps to inactivate genes that are not needed in specific cells or at specific times, and provides a way to protect the genetic material from damage. Heterochromatin tends to form when an enzyme called a lysine methyltransferase chemically modifies some of the proteins associated with the DNA, which are known as histones. This enzyme modifies only some of the histones to get the process started, while a second protein then binds to the modified histones and causes more of the DNA to become packaged up as heterochromatin. In 2012, researchers reported that the version of the lysine methyltransferase enzyme from yeast binds to RNA molecules via a portion known as its chromodomain. Moreover, the enzyme needed to bind to RNA to help heterochromatin to form. A similar mechanism also occurs in fruit flies, another organism that is commonly studied in the laboratory. However, it was not clear if it happened in mammals like mice and humans. Now, Shirai, Kawaguchi et al. – who include many of the researchers involved in the 2012 study – report that the corresponding enzyme from mice can also bind to RNA molecules via its chromodomain. Further experiments showed that this activity was closely linked with the enzyme’s ability to target the correct histones and efficiently form heterochromatin. The first experiments were conducted using purified enzymes in the laboratory, while follow-up experiments looked at the enzyme’s activity within mouse cells. Other studies have previously reported that mutant mice lacking the lysine methyltransferase enzyme have defective heterochromatin, tend to die young and have genetic instabilities that are associated with an increased risk of tumors and male infertility. The new findings of Shirai, Kawaguchi et al. reveal that the mechanism behind the establishment of heterochromatin has mostly likely been conserved over a billion years of evolution, which is when yeast and mammals last shared a common ancestor. By revealing more about how mammalian cells can protect their DNA, these new findings could also mark an important step toward understanding and preventing birth defects that are caused when an embryo’s genetic material becomes damaged. DOI:http://dx.doi.org/10.7554/eLife.25317.002
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Affiliation(s)
| | - Takayuki Kawaguchi
- Division of Chromatin Regulation, National Institute for Basic Biology, Okazaki, Japan.,Graduate School of Natural Sciences, Nagoya City University, Nagoya, Japan
| | - Hideaki Shimojo
- Graduate School of Medical Life Science, Yokohama City University, Yokohama, Japan
| | | | | | - Yoshifumi Nishimura
- Graduate School of Medical Life Science, Yokohama City University, Yokohama, Japan
| | - Hiroshi Kimura
- Cell Biology Unit, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Japan
| | - Jun-Ichi Nakayama
- Division of Chromatin Regulation, National Institute for Basic Biology, Okazaki, Japan.,Graduate School of Natural Sciences, Nagoya City University, Nagoya, Japan
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27
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Tan H, Liu T, Zhang J, Zhou T. Random positioning of nucleosomes enhances heritable bistability. MOLECULAR BIOSYSTEMS 2017; 13:132-141. [PMID: 27833942 DOI: 10.1039/c6mb00729e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Chromosomal regions are often dynamically modified by histones, leading to the uncertainty of nucleosome positions. Experiments have provided evidence for this randomness, but it is unclear how it impacts epigenetic heritability. Here, by analyzing a mechanic model at the molecular level, which considers three representative types of nucleosomes (unmodified, methylated, and acetylated) and dynamic nucleosome modifications, we find that in contrast to the equidistance partition of nucleosomes, random partition can significantly enhance heritable bistability. Moreover, the more "chaotic" the nucleosome positions are, the better the heritable bistability is, in contrast to the previous view. In both cases of nucleosome positioning, heritable bistability occurs only when the total nucleosome number is beyond a threshold, and it depends strongly on the allocation rate that enzymes regulate transitions between different nucleosome types. Thus, we conclude that random positioning of nucleosomes is an unneglectable factor impacting heritable bistability. A point worth mentioning is that our model established on a master equation can easily be extended to include other more complex processes underlying dynamic nucleosome modifications.
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Affiliation(s)
- Heli Tan
- School of Mathematics, Sun Yat-Sen University, Guangzhou 510275, P. R. China. and School of Mathematics and Computational Science, Xiangtan University, XiangTan 411105, P. R. China
| | - Tuoqi Liu
- School of Mathematics, Sun Yat-Sen University, Guangzhou 510275, P. R. China.
| | - Jiajun Zhang
- School of Mathematics, Sun Yat-Sen University, Guangzhou 510275, P. R. China.
| | - Tianshou Zhou
- School of Mathematics, Sun Yat-Sen University, Guangzhou 510275, P. R. China.
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The Drosophila DAXX-Like Protein (DLP) Cooperates with ASF1 for H3.3 Deposition and Heterochromatin Formation. Mol Cell Biol 2017; 37:MCB.00597-16. [PMID: 28320872 DOI: 10.1128/mcb.00597-16] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 03/09/2017] [Indexed: 01/22/2023] Open
Abstract
Histone variants are nonallelic isoforms of canonical histones, and they are deposited, in contrast to canonical histones, in a replication-independent (RI) manner. RI deposition of H3.3, a histone variant from the H3.3 family, is mediated in mammals by distinct pathways involving either the histone regulator A (HIRA) complex or the death-associated protein (DAXX)/α-thalassemia X-linked mental retardation protein (ATRX) complex. Here, we investigated the function of the Drosophila DAXX-like protein (DLP) by using both fly genetic approaches and protein biochemistry. DLP specifically interacts with H3.3 and shows a prominent localization on the base of the X chromosome, where it appears to act in concert with XNP, the Drosophila homolog of ATRX, in heterochromatin assembly and maintenance. The functional association between DLP and XNP is further supported by a series of experiments that illustrate genetic interactions and the DLP-XNP-dependent localization of specific chromosomal proteins. In addition, DLP both participates in the RI deposition of H3.3 and associates with anti-silencing factor 1 (ASF1). We suggest, in agreement with a recently proposed model, that DLP and ASF1 are part of a predeposition complex, which is recruited by XNP and is necessary to prevent DNA exposure in the nucleus.
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Kidder BL, Hu G, Cui K, Zhao K. SMYD5 regulates H4K20me3-marked heterochromatin to safeguard ES cell self-renewal and prevent spurious differentiation. Epigenetics Chromatin 2017; 10:8. [PMID: 28250819 PMCID: PMC5324308 DOI: 10.1186/s13072-017-0115-7] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 02/14/2017] [Indexed: 12/27/2022] Open
Abstract
Background Epigenetic regulation of chromatin states is thought to control the self-renewal and differentiation of embryonic stem (ES) cells. However, the roles of repressive histone modifications such as trimethylated histone 4 lysine 20 (H4K20me3) in pluripotency and development are largely unknown. Results Here, we show that the histone lysine methyltransferase SMYD5 mediates H4K20me3 at heterochromatin regions. Depletion of SMYD5 leads to compromised self-renewal, including dysregulated expression of OCT4 targets, and perturbed differentiation. SMYD5-bound regions are enriched with repetitive DNA elements. Knockdown of SMYD5 results in a global decrease of H4K20me3 levels, a redistribution of heterochromatin constituents including H3K9me3/2, G9a, and HP1α, and de-repression of endogenous retroelements. A loss of SMYD5-dependent silencing of heterochromatin nearby genic regions leads to upregulated expression of lineage-specific genes, thus contributing to the decreased self-renewal and perturbed differentiation of SMYD5-depleted ES cells. Conclusions Altogether, these findings implicate a role for SMYD5 in regulating ES cell self-renewal and H4K20me3-marked heterochromatin. Electronic supplementary material The online version of this article (doi:10.1186/s13072-017-0115-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Benjamin L Kidder
- Department of Oncology, Wayne State University School of Medicine, Detroit, MI USA.,Karmanos Cancer Institute, Wayne State University School of Medicine, Detroit, MI USA.,Systems Biology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD USA
| | - Gangqing Hu
- Systems Biology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD USA
| | - Kairong Cui
- Systems Biology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD USA
| | - Keji Zhao
- Systems Biology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD USA
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30
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Epigenetic origin of evolutionary novel centromeres. Sci Rep 2017; 7:41980. [PMID: 28155877 PMCID: PMC5290474 DOI: 10.1038/srep41980] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Accepted: 01/04/2017] [Indexed: 01/10/2023] Open
Abstract
Most evolutionary new centromeres (ENC) are composed of large arrays of satellite DNA and surrounded by segmental duplications. However, the hypothesis is that ENCs are seeded in an anonymous sequence and only over time have acquired the complexity of "normal" centromeres. Up to now evidence to test this hypothesis was lacking. We recently discovered that the well-known polymorphism of orangutan chromosome 12 was due to the presence of an ENC. We sequenced the genome of an orangutan homozygous for the ENC, and we focused our analysis on the comparison of the ENC domain with respect to its wild type counterpart. No significant variations were found. This finding is the first clear evidence that ENC seedings are epigenetic in nature. The compaction of the ENC domain was found significantly higher than the corresponding WT region and, interestingly, the expression of the only gene embedded in the region was significantly repressed.
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Alberro N, Torrent-Sucarrat M, Arrastia I, Arrieta A, Cossío FP. Two-State Reactivity of Histone Demethylases Containing Jumonji-C Active Sites: Different Mechanisms for Different Methylation Degrees. Chemistry 2016; 23:137-148. [DOI: 10.1002/chem.201604219] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Indexed: 01/08/2023]
Affiliation(s)
- Nerea Alberro
- Department of Organic Chemistry I; Universidad del País Vasco/Euskal Herriko Unibertsitatea (UPV/EHU); Centro de Innovación en Química Avanzada (ORFEO-CINQA); Manuel Lardizabal Ibilbidea 3 20018 San Sebastián/Donostia Spain
| | - Miquel Torrent-Sucarrat
- Department of Organic Chemistry I; Universidad del País Vasco/Euskal Herriko Unibertsitatea (UPV/EHU); Centro de Innovación en Química Avanzada (ORFEO-CINQA); Manuel Lardizabal Ibilbidea 3 20018 San Sebastián/Donostia Spain
- Donostia International Physics Center (DIPC); Manuel Lardizabal Ibilbidea 4 20018 San Sebastián/Donostia Spain
- Ikerbasque; Basque Foundation for Science; María Díaz de Haro 3, 6 floor 48013 Bilbao Spain
| | - Iosune Arrastia
- Donostia International Physics Center (DIPC); Manuel Lardizabal Ibilbidea 4 20018 San Sebastián/Donostia Spain
| | - Ana Arrieta
- Department of Organic Chemistry I; Universidad del País Vasco/Euskal Herriko Unibertsitatea (UPV/EHU); Centro de Innovación en Química Avanzada (ORFEO-CINQA); Manuel Lardizabal Ibilbidea 3 20018 San Sebastián/Donostia Spain
| | - Fernando P. Cossío
- Department of Organic Chemistry I; Universidad del País Vasco/Euskal Herriko Unibertsitatea (UPV/EHU); Centro de Innovación en Química Avanzada (ORFEO-CINQA); Manuel Lardizabal Ibilbidea 3 20018 San Sebastián/Donostia Spain
- Donostia International Physics Center (DIPC); Manuel Lardizabal Ibilbidea 4 20018 San Sebastián/Donostia Spain
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32
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Muramatsu D, Kimura H, Kotoshiba K, Tachibana M, Shinkai Y. Pericentric H3K9me3 Formation by HP1 Interaction-defective Histone Methyltransferase Suv39h1. Cell Struct Funct 2016; 41:145-152. [PMID: 27733730 DOI: 10.1247/csf.16013] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Pericentric regions form epigenetically organized, silent heterochromatin structures that accumulate histone H3 lysine 9 tri-methylation (H3K9me3) and heterochromatin protein 1 (HP1), a methylated H3K9-binding protein. At pericentric regions, Suv39h is the major enzyme that generates H3K9me3. Suv39h also interacts directly with HP1. However, the importance of HP1 interaction for Suv39h-mediated H3K9me3 formation at the pericentromere is not well characterized. To address this question, we introduced HP1 binding-defective, N-terminally truncated mouse Suv39h1 (ΔN) into Suv39h-deficient cells. Pericentric H3K9me3-positive cells were not detected by endogenous-level expression of ΔN. Notably, ΔN could induce pericentric accumulation of H3K9me3 as wild type Suv39h1 did if it was overexpressed. These findings demonstrate that the N-terminal region of Suv39h1, presumably via HP1-Suv39h1 interaction, is required for Suv39h1-mediated pericentric H3K9me3 formation, but can be overridden if Suv39h1 is overproduced, indicating that Suv39h1-mediated heterochromatin formation is controlled by multiple modules, including HP1.
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Abstract
Trans-inactivation is the repression of genes on a normal chromosome under the influence of a rearranged homologous chromosome demonstrating the position effect variegation (PEV). This phenomenon was studied in detail on the example of brownDominant allele causing the repression of wild-type brown gene on the opposite chromosome. We have investigated another trans-inactivation-inducing chromosome rearrangement, In(2)A4 inversion. In both cases, brownDominant and In(2)A4, the repression seems to be the result of dragging of the euchromatic region of the normal chromosome into the heterochromatic environment. It was found that cis-inactivation (classical PEV) and trans-inactivation show different patterns of distribution along the chromosome and respond differently to PEV modifying genes. It appears that the causative mechanism of trans-inactivation is de novo heterochromatin assembly on euchromatic sequences dragged into the heterochromatic nuclear compartment. Trans-inactivation turns out to be the result of a combination of heterochromatin-induced position effect and the somatic interphase chromosome pairing that is widespread in Diptera.
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Affiliation(s)
- Aleksei S Shatskikh
- a Department of Molecular Genetics of the Cell , Institute of Molecular Genetics, Russian Academy of Science , Moscow , Russia
| | - Yuriy A Abramov
- a Department of Molecular Genetics of the Cell , Institute of Molecular Genetics, Russian Academy of Science , Moscow , Russia
| | - Sergey A Lavrov
- a Department of Molecular Genetics of the Cell , Institute of Molecular Genetics, Russian Academy of Science , Moscow , Russia
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34
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Gong L, Govan JM, Evans EB, Dai H, Wang E, Lee SW, Lin HK, Lazar AJ, Mills GB, Lin SY. Nuclear PTEN tumor-suppressor functions through maintaining heterochromatin structure. Cell Cycle 2016; 14:2323-32. [PMID: 25946202 DOI: 10.1080/15384101.2015.1044174] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The tumor suppressor, PTEN, is one of the most commonly mutated genes in cancer. Recently, PTEN has been shown to localize in the nucleus and is required to maintain genomic stability. Here, we show that nuclear PTEN, independent of its phosphatase activity, is essential for maintaining heterochromatin structure. Depletion of PTEN leads to loss of heterochromatic foci, decreased chromatin compaction, overexpression of heterochromatic genes, and reduced protein stability of heterochromatin protein 1 α. We found that the C-terminus of PTEN is required to maintain heterochromatin structure. Additionally, cancer-associated PTEN mutants lost their tumor-suppressor function when their heterochromatin structure was compromised. We propose that this novel role of PTEN accounts for its function in guarding genomic stability and suppressing tumor development.
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Affiliation(s)
- Lili Gong
- a Department of Systems Biology ; The University of Texas MD Anderson Cancer Center ; Houston , TX USA
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35
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Matsumura Y, Nakaki R, Inagaki T, Yoshida A, Kano Y, Kimura H, Tanaka T, Tsutsumi S, Nakao M, Doi T, Fukami K, Osborne TF, Kodama T, Aburatani H, Sakai J. H3K4/H3K9me3 Bivalent Chromatin Domains Targeted by Lineage-Specific DNA Methylation Pauses Adipocyte Differentiation. Mol Cell 2016; 60:584-96. [PMID: 26590716 DOI: 10.1016/j.molcel.2015.10.025] [Citation(s) in RCA: 152] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Revised: 08/11/2015] [Accepted: 10/12/2015] [Indexed: 12/29/2022]
Abstract
Bivalent H3K4me3 and H3K27me3 chromatin domains in embryonic stem cells keep active developmental regulatory genes expressed at very low levels and poised for activation. Here, we show an alternative and previously unknown bivalent modified histone signature in lineage-committed mesenchymal stem cells and preadipocytes that pairs H3K4me3 with H3K9me3 to maintain adipogenic master regulatory genes (Cebpa and Pparg) expressed at low levels yet poised for activation when differentiation is required. We show lineage-specific gene-body DNA methylation recruits H3K9 methyltransferase SETDB1, which methylates H3K9 immediately downstream of transcription start sites marked with H3K4me3 to establish the bivalent domain. At the Cebpa locus, this prevents transcription factor C/EBPβ binding, histone acetylation, and further H3K4me3 deposition and is associated with pausing of RNA polymerase II, which limits Cebpa gene expression and adipogenesis.
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Affiliation(s)
- Yoshihiro Matsumura
- Division of Metabolic Medicine, The University of Tokyo, 4-6-1, Komaba, Meguro-ku, Tokyo 153-8904, Japan; The Translational Systems Biology and Medicine Initiative (TSBMI), Center for Disease Biology and Integrative Medicine, Faculty of Medicine, The University of Tokyo, Tokyo 113-8655, Japan.
| | - Ryo Nakaki
- Genome Science Division, The University of Tokyo, 4-6-1, Komaba, Meguro-ku, Tokyo 153-8904, Japan
| | - Takeshi Inagaki
- Division of Metabolic Medicine, The University of Tokyo, 4-6-1, Komaba, Meguro-ku, Tokyo 153-8904, Japan; The Translational Systems Biology and Medicine Initiative (TSBMI), Center for Disease Biology and Integrative Medicine, Faculty of Medicine, The University of Tokyo, Tokyo 113-8655, Japan
| | - Ayano Yoshida
- Division of Metabolic Medicine, The University of Tokyo, 4-6-1, Komaba, Meguro-ku, Tokyo 153-8904, Japan; Laboratory of Genome and Biosignals, Tokyo University of Pharmacy and Life Science, Tokyo 192-0392, Japan
| | - Yuka Kano
- Division of Metabolic Medicine, The University of Tokyo, 4-6-1, Komaba, Meguro-ku, Tokyo 153-8904, Japan
| | - Hiroshi Kimura
- Department of Biological Sciences, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Yokohama 226-8501, Japan
| | - Toshiya Tanaka
- Division of Metabolic Medicine, The University of Tokyo, 4-6-1, Komaba, Meguro-ku, Tokyo 153-8904, Japan; Laboratory for Systems Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, 4-6-1, Komaba, Meguro-ku, Tokyo 153-8904, Japan; The Translational Systems Biology and Medicine Initiative (TSBMI), Center for Disease Biology and Integrative Medicine, Faculty of Medicine, The University of Tokyo, Tokyo 113-8655, Japan
| | - Shuichi Tsutsumi
- Genome Science Division, The University of Tokyo, 4-6-1, Komaba, Meguro-ku, Tokyo 153-8904, Japan
| | - Mitsuyoshi Nakao
- Department of Medical Cell Biology, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto 860-0811, Japan
| | - Takefumi Doi
- Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka 565-0871, Japan
| | - Kiyoko Fukami
- Laboratory of Genome and Biosignals, Tokyo University of Pharmacy and Life Science, Tokyo 192-0392, Japan
| | - Timothy F Osborne
- Metabolic Disease Program, Sanford-Burnham Medical Research Institute, Orlando, FL 32827, USA
| | - Tatsuhiko Kodama
- Laboratory for Systems Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, 4-6-1, Komaba, Meguro-ku, Tokyo 153-8904, Japan
| | - Hiroyuki Aburatani
- Genome Science Division, The University of Tokyo, 4-6-1, Komaba, Meguro-ku, Tokyo 153-8904, Japan; The Translational Systems Biology and Medicine Initiative (TSBMI), Center for Disease Biology and Integrative Medicine, Faculty of Medicine, The University of Tokyo, Tokyo 113-8655, Japan
| | - Juro Sakai
- Division of Metabolic Medicine, The University of Tokyo, 4-6-1, Komaba, Meguro-ku, Tokyo 153-8904, Japan; The Translational Systems Biology and Medicine Initiative (TSBMI), Center for Disease Biology and Integrative Medicine, Faculty of Medicine, The University of Tokyo, Tokyo 113-8655, Japan.
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36
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Shimojo H, Kawaguchi A, Oda T, Hashiguchi N, Omori S, Moritsugu K, Kidera A, Hiragami-Hamada K, Nakayama JI, Sato M, Nishimura Y. Extended string-like binding of the phosphorylated HP1α N-terminal tail to the lysine 9-methylated histone H3 tail. Sci Rep 2016; 6:22527. [PMID: 26934956 PMCID: PMC4776139 DOI: 10.1038/srep22527] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Accepted: 02/15/2016] [Indexed: 11/09/2022] Open
Abstract
The chromodomain of HP1α binds directly to lysine 9-methylated histone H3 (H3K9me). This interaction is enhanced by phosphorylation of serine residues in the N-terminal tail of HP1α by unknown mechanism. Here we show that phosphorylation modulates flexibility of HP1α's N-terminal tail, which strengthens the interaction with H3. NMR analysis of HP1α's chromodomain with N-terminal tail reveals that phosphorylation does not change the overall tertiary structure, but apparently reduces the tail dynamics. Small angle X-ray scattering confirms that phosphorylation contributes to extending HP1α's N-terminal tail. Systematic analysis using deletion mutants and replica exchange molecular dynamics simulations indicate that the phosphorylated serines and following acidic segment behave like an extended string and dynamically bind to H3 basic residues; without phosphorylation, the most N-terminal basic segment of HP1α inhibits interaction of the acidic segment with H3. Thus, the dynamic string-like behavior of HP1α's N-terminal tail underlies the enhancement in H3 binding due to phosphorylation.
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Affiliation(s)
- Hideaki Shimojo
- Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
| | - Ayumi Kawaguchi
- Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
| | - Takashi Oda
- Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
| | - Nobuto Hashiguchi
- Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
| | - Satoshi Omori
- Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
| | - Kei Moritsugu
- Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
| | - Akinori Kidera
- Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
| | - Kyoko Hiragami-Hamada
- Division of Genome Technologies, RIKEN Center for Life Science Technologies, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
| | - Jun-Ichi Nakayama
- Graduate School of Natural Sciences, Nagoya City University, 1 Yamanohata, Mizuho, Nagoya, Aichi 467-8501, Japan
| | - Mamoru Sato
- Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
| | - Yoshifumi Nishimura
- Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
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Fu W, Liu N, Qiao Q, Wang M, Min J, Zhu B, Xu RM, Yang N. Structural Basis for Substrate Preference of SMYD3, a SET Domain-containing Protein Lysine Methyltransferase. J Biol Chem 2016; 291:9173-80. [PMID: 26929412 DOI: 10.1074/jbc.m115.709832] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Indexed: 01/05/2023] Open
Abstract
SMYD3 is a SET domain-containing N-lysine methyltransferase associated with multiple cancers. Its reported substrates include histones (H3K4 and H4K5), vascular endothelial growth factor receptor 1 (VEGFR1 Lys(831)) and MAP3 kinase kinase (MAP3K2 Lys(260)). To reveal the structural basis for substrate preference and the catalytic mechanism of SMYD3, we have solved its co-crystal structures with VEGFR1 and MAP3K2 peptides. Our structural and biochemical analyses show that MAP3K2 serves as a robust substrate of SMYD3 because of the presence of a phenylalanine residue at the -2 position. A shallow hydrophobic pocket on SMYD3 accommodates the binding of the phenylalanine and promotes efficient catalytic activities of SMYD3. By contrast, SMYD3 displayed a weak activity toward a VEGFR1 peptide, and the location of the acceptor lysine in the folded kinase domain of VEGFR1 requires drastic conformational rearrangements for juxtaposition of the acceptor lysine with the enzymatic active site. Our results clearly revealed structural determinants for the substrate preference of SMYD3 and provided mechanistic insights into lysine methylation of MAP3K2. The knowledge should be useful for the development of SMYD3 inhibitors in the fight against MAP3K2 and Ras-driven cancer.
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Affiliation(s)
- Weiqi Fu
- From the National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China, the University of Chinese Academy of Sciences, Beijing 100049, China, and
| | - Nan Liu
- From the National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Qi Qiao
- From the National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China, the University of Chinese Academy of Sciences, Beijing 100049, China, and
| | - Mingzhu Wang
- From the National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Jinrong Min
- the Structural Genomics Consortium, University of Toronto, Toronto, Ontario M5G 1L7, Canada
| | - Bing Zhu
- From the National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China, the University of Chinese Academy of Sciences, Beijing 100049, China, and
| | - Rui-Ming Xu
- From the National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China, the University of Chinese Academy of Sciences, Beijing 100049, China, and
| | - Na Yang
- From the National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China, the University of Chinese Academy of Sciences, Beijing 100049, China, and
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38
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Heterochromatin components in germline stem cell maintenance. Sci Rep 2015; 5:17463. [PMID: 26626305 PMCID: PMC4667240 DOI: 10.1038/srep17463] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Accepted: 10/30/2015] [Indexed: 01/23/2023] Open
Abstract
Stem cell maintenance requires expression of genes essential for stemness and repression of differentiation genes. How this is achieved remains incompletely understood. Here we investigate the requirement for central components of heterochromatin, Heterochromatin Protein 1 (HP1) and the histone H3 lys9 methyltransferase Su(var)3-9, in the Drosophila male germline stem cell (GSC) self-renewal, a paradigm for studying adult stem cell behavior. We found that mutations or RNAi knock down of HP1 or Su(var)3-9 cause loss of GSCs, accompanied by defects in cell division or survival and premature expression of the differentiation gene bag of marbles (bam). Conversely, over-expressing HP1 increases GSC number in wildtype flies and, strikingly, restores fertility to the sterile hopscotch (hop) mutant flies that lack niche signals. These results suggest that the central components of heterochromatin play roles including repressing differentiation genes in Drosophila male GSC maintenance.
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The Differences Between Cis- and Trans-Gene Inactivation Caused by Heterochromatin in Drosophila. Genetics 2015; 202:93-106. [PMID: 26500261 DOI: 10.1534/genetics.115.181693] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Accepted: 10/13/2015] [Indexed: 11/18/2022] Open
Abstract
Position-effect variegation (PEV) is the epigenetic disruption of gene expression near the de novo-formed euchromatin-heterochromatin border. Heterochromatic cis-inactivation may be accompanied by the trans-inactivation of genes on a normal homologous chromosome in trans-heterozygous combination with a PEV-inducing rearrangement. We characterize a new genetic system, inversion In(2)A4, demonstrating cis-acting PEV as well as trans-inactivation of the reporter transgenes on the homologous nonrearranged chromosome. The cis-effect of heterochromatin in the inversion results not only in repression but also in activation of genes, and it varies at different developmental stages. While cis-actions affect only a few juxtaposed genes, trans-inactivation is observed in a 500-kb region and demonstrates а nonuniform pattern of repression with intermingled regions where no transgene repression occurs. There is no repression around the histone gene cluster and in some other euchromatic sites. trans-Inactivation is accompanied by dragging of euchromatic regions into the heterochromatic compartment, but the histone gene cluster, located in the middle of the trans-inactivated region, was shown to be evicted from the heterochromatin. We demonstrate that trans-inactivation is followed by de novo HP1a accumulation in the affected transgene; trans-inactivation is specifically favored by the chromatin remodeler SAYP and prevented by Argonaute AGO2.
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40
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Rapkin LM, Ahmed K, Dulev S, Li R, Kimura H, Ishov AM, Bazett-Jones DP. The histone chaperone DAXX maintains the structural organization of heterochromatin domains. Epigenetics Chromatin 2015; 8:44. [PMID: 26500702 PMCID: PMC4617904 DOI: 10.1186/s13072-015-0036-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Accepted: 10/07/2015] [Indexed: 12/20/2022] Open
Abstract
Background The death domain-associated protein (DAXX) collaborates with accessory proteins to deposit the histone variant H3.3 into mouse telomeric and pericentromeric repeat DNA. Pericentromeric repeats are the main genetic contributor to spatially discrete, compact, constitutive heterochromatic structures called chromocentres. Chromocentres are enriched in the H3K9me3 histone modification and serve as integral, functionally important components of nuclear organization. To date, the role of DAXX as an H3.3-specific histone chaperone has been investigated primarily using biochemical approaches which provide genome-wide views on cell populations and information on changes in local chromatin structures. However, the global chromatin and subnuclear reorganization events that coincide with these changes remain to be investigated. Results Using electron spectroscopic imagine (ESI), a specialized form of energy-filtered transmission electron microscopy that allows us to visualize chromatin domains in situ with high contrast and spatial resolution, we show that in the absence of DAXX, H3K9me3-enriched domains are structurally altered and become uncoupled from major satellite DNA. In addition, the structural integrity of nucleoli and the organization of ribosomal DNA (rDNA) are disrupted. Moreover, the absence of DAXX leads to chromatin that is more sensitive, on a global level, to micrococcal nuclease digestion. Conclusions We identify a novel role of DAXX as a major regulator of subnuclear organization through the maintenance of the global heterochromatin structural landscape. As well, we show, for the first time, that the loss of a histone chaperone can have severe consequences for global nuclear organization. Electronic supplementary material The online version of this article (doi:10.1186/s13072-015-0036-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Lindsy M Rapkin
- Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON M5G 0A4 Canada ; Department of Biochemistry, The University of Toronto, Toronto, ON M5S 1A8 Canada
| | - Kashif Ahmed
- Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON M5G 0A4 Canada
| | - Stanimir Dulev
- Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON M5G 0A4 Canada
| | - Ren Li
- Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON M5G 0A4 Canada
| | - Hiroshi Kimura
- Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-Ku, Yokohama 226-8501 Japan
| | - Alexander M Ishov
- Department of Anatomy and Cell Biology, University of Florida College of Medicine, and University of Florida Cancer Center, Gainesville, FL 32610 USA
| | - David P Bazett-Jones
- Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON M5G 0A4 Canada ; Department of Biochemistry, The University of Toronto, Toronto, ON M5S 1A8 Canada
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41
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Guo J, He H, Liu Q, Zhang F, Lv J, Zeng T, Gu N, Wu Q. Identification and Epigenetic Analysis of a Maternally Imprinted Gene Qpct. Mol Cells 2015; 38:859-65. [PMID: 26447138 PMCID: PMC4625067 DOI: 10.14348/molcells.2015.0098] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Revised: 07/09/2015] [Accepted: 07/13/2015] [Indexed: 11/27/2022] Open
Abstract
Most imprinted genes are concerned with embryonic development, especially placental development. Here, we identified a placenta-specific imprinted gene Qpct. Our results show that Qpct is widely expressed during early embryonic development and can be detected in the telecephalon, midbrain, and rhombencephalon at E9.5b-E11.5. Moreover, Qpct is strikingly expressed in the brain, lung and liver in E15.5. Expression signals for Qpct achieved a peak at E15.5 during placental development and were only detected in the labyrinth layer in E15.5 placenta. ChIP assay results suggest that the modification of histone H3K4me3 can result in maternal activating of Qpct.
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Affiliation(s)
- Jing Guo
- School of Life Science and Technology, State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, 150001, Heilongjiang,
China
| | - Hongjuan He
- School of Life Science and Technology, State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, 150001, Heilongjiang,
China
| | - Qi Liu
- School of Life Science and Technology, State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, 150001, Heilongjiang,
China
| | - Fengwei Zhang
- School of Life Science and Technology, State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, 150001, Heilongjiang,
China
| | - Jie Lv
- School of Life Science and Technology, State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, 150001, Heilongjiang,
China
| | - Tiebo Zeng
- School of Life Science and Technology, State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, 150001, Heilongjiang,
China
| | - Ning Gu
- School of Life Science and Technology, State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, 150001, Heilongjiang,
China
| | - Qiong Wu
- School of Life Science and Technology, State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, 150001, Heilongjiang,
China
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42
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Rajeevkumar S, Anunanthini P, Sathishkumar R. Epigenetic silencing in transgenic plants. FRONTIERS IN PLANT SCIENCE 2015; 6:693. [PMID: 26442010 PMCID: PMC4564723 DOI: 10.3389/fpls.2015.00693] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Accepted: 08/21/2015] [Indexed: 05/18/2023]
Abstract
Epigenetic silencing is a natural phenomenon in which the expression of genes is regulated through modifications of DNA, RNA, or histone proteins. It is a mechanism for defending host genomes against the effects of transposable elements and viral infection, and acts as a modulator of expression of duplicated gene family members and as a silencer of transgenes. A major breakthrough in understanding the mechanism of epigenetic silencing was the discovery of silencing in transgenic tobacco plants due to the interaction between two homologous promoters. The molecular mechanism of epigenetic mechanism is highly complicated and it is not completely understood yet. Two different molecular routes have been proposed for this, that is, transcriptional gene silencing, which is associated with heavy methylation of promoter regions and blocks the transcription of transgenes, and post-transcriptional gene silencing (PTGS), the basic mechanism is degradation of the cytosolic mRNA of transgenes or endogenous genes. Undesired transgene silencing is of major concern in the transgenic technologies used in crop improvement. A complete understanding of this phenomenon will be very useful for transgenic applications, where silencing of specific genes is required. The current status of epigenetic silencing in transgenic technology is discussed and summarized in this mini-review.
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Affiliation(s)
- Sarma Rajeevkumar
- Molecular Plant Biology and Biotechnology Division, Central Institute of Medicinal and Aromatic Plants Research Centre, BangaloreIndia
| | - Pushpanathan Anunanthini
- Plant Genetic Engineering Laboratory, Department of Biotechnology, Bharathiar University, CoimbatoreIndia
| | - Ramalingam Sathishkumar
- Plant Genetic Engineering Laboratory, Department of Biotechnology, Bharathiar University, CoimbatoreIndia
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43
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Zhao Y, Garcia BA. Comprehensive Catalog of Currently Documented Histone Modifications. Cold Spring Harb Perspect Biol 2015; 7:a025064. [PMID: 26330523 DOI: 10.1101/cshperspect.a025064] [Citation(s) in RCA: 257] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Modern techniques in molecular biology, genomics, and mass spectrometry-based proteomics have identified a large number of novel histone posttranslational modifications (PTMs), many of whose functions are still under intense investigation. Here, we catalog histone PTMs under two classes: first, those whose functions have been fairly well studied and, second, those PTMs that have been more recently identified but whose functions remain unclear. We hope that this will be a useful resource for researchers from all biological or technical backgrounds, aiding in their chromatin and epigenetic pursuits.
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Affiliation(s)
- Yingming Zhao
- Ben May Department for Cancer Research, The University of Chicago, Chicago, Illinois 60637
| | - Benjamin A Garcia
- Epigenetics Program, Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
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44
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Matsuda A, Chikashige Y, Ding DQ, Ohtsuki C, Mori C, Asakawa H, Kimura H, Haraguchi T, Hiraoka Y. Highly condensed chromatins are formed adjacent to subtelomeric and decondensed silent chromatin in fission yeast. Nat Commun 2015; 6:7753. [PMID: 26205977 PMCID: PMC4525289 DOI: 10.1038/ncomms8753] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Accepted: 06/08/2015] [Indexed: 11/09/2022] Open
Abstract
It is generally believed that silent chromatin is condensed and transcriptionally active chromatin is decondensed. However, little is known about the relationship between the condensation levels and gene expression. Here we report the condensation levels of interphase chromatin in the fission yeast Schizosaccharomyces pombe examined by super-resolution fluorescence microscopy. Unexpectedly, silent chromatin is less condensed than the euchromatin. Furthermore, the telomeric silent regions are flanked by highly condensed chromatin bodies, or 'knobs'. Knob regions span ∼50 kb of sequence devoid of methylated histones. Knob condensation is independent of HP1 homologue Swi6 and other gene silencing factors. Disruption of methylation at lysine 36 of histone H3 (H3K36) eliminates knob formation and gene repression at the subtelomeric and adjacent knob regions. Thus, epigenetic marks at H3K36 play crucial roles in the formation of a unique chromatin structure and in gene regulation at those regions in S. pombe.
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Affiliation(s)
- Atsushi Matsuda
- Advanced ICT Research Institute Kobe, National Institute of Information and Communications Technology, 588-2, Iwaoka, Iwaoka-cho, Kobe 651-2492, Japan
- Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka, Suita 565-0871, Japan
| | - Yuji Chikashige
- Advanced ICT Research Institute Kobe, National Institute of Information and Communications Technology, 588-2, Iwaoka, Iwaoka-cho, Kobe 651-2492, Japan
| | - Da-Qiao Ding
- Advanced ICT Research Institute Kobe, National Institute of Information and Communications Technology, 588-2, Iwaoka, Iwaoka-cho, Kobe 651-2492, Japan
| | - Chizuru Ohtsuki
- Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka, Suita 565-0871, Japan
| | - Chie Mori
- Advanced ICT Research Institute Kobe, National Institute of Information and Communications Technology, 588-2, Iwaoka, Iwaoka-cho, Kobe 651-2492, Japan
| | - Haruhiko Asakawa
- Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka, Suita 565-0871, Japan
| | - Hiroshi Kimura
- Department of Biological Sciences, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, 4259-B, Nagatsuda, Yokohama 226-8501, Japan
| | - Tokuko Haraguchi
- Advanced ICT Research Institute Kobe, National Institute of Information and Communications Technology, 588-2, Iwaoka, Iwaoka-cho, Kobe 651-2492, Japan
- Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka, Suita 565-0871, Japan
| | - Yasushi Hiraoka
- Advanced ICT Research Institute Kobe, National Institute of Information and Communications Technology, 588-2, Iwaoka, Iwaoka-cho, Kobe 651-2492, Japan
- Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka, Suita 565-0871, Japan
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45
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Robinson SR, Oliver AW, Chevassut TJ, Newbury SF. The 3' to 5' Exoribonuclease DIS3: From Structure and Mechanisms to Biological Functions and Role in Human Disease. Biomolecules 2015; 5:1515-39. [PMID: 26193331 PMCID: PMC4598762 DOI: 10.3390/biom5031515] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Revised: 07/01/2015] [Accepted: 07/06/2015] [Indexed: 12/03/2022] Open
Abstract
DIS3 is a conserved exoribonuclease and catalytic subunit of the exosome, a protein complex involved in the 3' to 5' degradation and processing of both nuclear and cytoplasmic RNA species. Recently, aberrant expression of DIS3 has been found to be implicated in a range of different cancers. Perhaps most striking is the finding that DIS3 is recurrently mutated in 11% of multiple myeloma patients. Much work has been done to elucidate the structural and biochemical characteristics of DIS3, including the mechanistic details of its role as an effector of RNA decay pathways. Nevertheless, we do not understand how DIS3 mutations can lead to cancer. There are a number of studies that pertain to the function of DIS3 at the organismal level. Mutant phenotypes in S. pombe, S. cerevisiae and Drosophila suggest DIS3 homologues have a common role in cell-cycle progression and microtubule assembly. DIS3 has also recently been implicated in antibody diversification of mouse B-cells. This article aims to review current knowledge of the structure, mechanisms and functions of DIS3 as well as highlighting the genetic patterns observed within myeloma patients, in order to yield insight into the putative role of DIS3 mutations in oncogenesis.
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Affiliation(s)
- Sophie R Robinson
- Medical Research Building, Brighton and Sussex Medical School, University of Sussex, Falmer, Brighton BN1 9PS, UK.
| | - Antony W Oliver
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9RQ, UK.
| | - Timothy J Chevassut
- Medical Research Building, Brighton and Sussex Medical School, University of Sussex, Falmer, Brighton BN1 9PS, UK.
| | - Sarah F Newbury
- Medical Research Building, Brighton and Sussex Medical School, University of Sussex, Falmer, Brighton BN1 9PS, UK.
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46
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Naumov GI, Kondratieva VI, Naumova ES. Hybrid sterility of the yeast Schizosaccharomyces pombe: Genetic genus and many species in statu nascendi? Microbiology (Reading) 2015. [DOI: 10.1134/s0026261715010099] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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47
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Chromatin function modifying elements in an industrial antibody production platform--comparison of UCOE, MAR, STAR and cHS4 elements. PLoS One 2015; 10:e0120096. [PMID: 25849659 PMCID: PMC4388700 DOI: 10.1371/journal.pone.0120096] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Accepted: 02/02/2015] [Indexed: 01/02/2023] Open
Abstract
The isolation of stably transfected cell lines suitable for the manufacture of biotherapeutic protein products can be an arduous process relying on the identification of a high expressing clone; this frequently involves transgene amplification and maintenance of the clones' expression over at least 60 generations. Maintenance of expression, or cell line stability, is highly dependent upon the nature of the genomic environment at the site of transgene integration, where epigenetic mechanisms lead to variable expression and silencing in the vast majority of cases. We have assessed four chromatin function modifying elements (A2UCOE, MAR X_S29, STAR40 and cHS4) for their ability to negate chromatin insertion site position effects and their ability to express and maintain monoclonal antibody expression. Each element was analysed by insertion into different positions within a vector, either flanking or between heavy chain (HC) and light chain (LC) antibody expression cassettes. Our results clearly show that the A2UCOE is the most beneficial element in this system, with stable cell pools and clones increasing antibody yields 6.5-fold and 6.75-fold respectively. Stability analysis demonstrated that the reduction in antibody expression, seen with cells transfected with the control vector over 120 generations, was mitigated in the clones containing A2UCOE-augmented transgenes. Analysis also showed that the A2UCOE reduced the amount of transgene promoter DNA methylation, which contributed to the maintenance of starting levels of expression.
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48
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Liu Z, Legant WR, Chen BC, Li L, Grimm JB, Lavis LD, Betzig E, Tjian R. 3D imaging of Sox2 enhancer clusters in embryonic stem cells. eLife 2014; 3:e04236. [PMID: 25537195 PMCID: PMC4381973 DOI: 10.7554/elife.04236] [Citation(s) in RCA: 163] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2014] [Accepted: 11/26/2014] [Indexed: 12/19/2022] Open
Abstract
Combinatorial cis-regulatory networks encoded in animal genomes represent the foundational gene expression mechanism for directing cell-fate commitment and maintenance of cell identity by transcription factors (TFs). However, the 3D spatial organization of cis-elements and how such sub-nuclear structures influence TF activity remain poorly understood. Here, we combine lattice light-sheet imaging, single-molecule tracking, numerical simulations, and ChIP-exo mapping to localize and functionally probe Sox2 enhancer-organization in living embryonic stem cells. Sox2 enhancers form 3D-clusters that are segregated from heterochromatin but overlap with a subset of Pol II enriched regions. Sox2 searches for specific binding targets via a 3D-diffusion dominant mode when shuttling long-distances between clusters while chromatin-bound states predominate within individual clusters. Thus, enhancer clustering may reduce global search efficiency but enables rapid local fine-tuning of TF search parameters. Our results suggest an integrated model linking cis-element 3D spatial distribution to local-versus-global target search modalities essential for regulating eukaryotic gene transcription.
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Affiliation(s)
- Zhe Liu
- Junior Fellow Program, Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, United States
| | - Wesley R Legant
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, United States
| | - Bi-Chang Chen
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, United States
| | - Li Li
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, United States
| | - Jonathan B Grimm
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, United States
| | - Luke D Lavis
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, United States
| | - Eric Betzig
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, United States
| | - Robert Tjian
- Transcription Imaging Consortium, Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, United States
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49
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Garrigues JM, Sidoli S, Garcia BA, Strome S. Defining heterochromatin in C. elegans through genome-wide analysis of the heterochromatin protein 1 homolog HPL-2. Genome Res 2014; 25:76-88. [PMID: 25467431 PMCID: PMC4317175 DOI: 10.1101/gr.180489.114] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Formation of heterochromatin serves a critical role in organizing the genome and regulating gene expression. In most organisms, heterochromatin flanks centromeres and telomeres. To identify heterochromatic regions in the heavily studied model C. elegans, which possesses holocentric chromosomes with dispersed centromeres, we analyzed the genome-wide distribution of the heterochromatin protein 1 (HP1) ortholog HPL-2 and compared its distribution to other features commonly associated with heterochromatin. HPL-2 binding highly correlates with histone H3 mono- and dimethylated at lysine 9 (H3K9me1 and H3K9me2) and forms broad domains on autosomal arms. Although HPL-2, like other HP1 orthologs, binds H3K9me peptides in vitro, the distribution of HPL-2 in vivo appears relatively normal in mutant embryos that lack H3K9me, demonstrating that the chromosomal distribution of HPL-2 can be achieved in an H3K9me-independent manner. Consistent with HPL-2 serving roles independent of H3K9me, hpl-2 mutant worms display more severe defects than mutant worms lacking H3K9me. HPL-2 binding is enriched for repetitive sequences, and on chromosome arms is anticorrelated with centromeres. At the genic level, HPL-2 preferentially associates with well-expressed genes, and loss of HPL-2 results in up-regulation of some binding targets and down-regulation of others. Our work defines heterochromatin in an important model organism and uncovers both shared and distinctive properties of heterochromatin relative to other systems.
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Affiliation(s)
- Jacob M Garrigues
- Department of Molecular, Cell, and Developmental Biology, University of California Santa Cruz, Santa Cruz, California 95064, USA
| | - Simone Sidoli
- Epigenetics Program, Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Benjamin A Garcia
- Epigenetics Program, Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Susan Strome
- Department of Molecular, Cell, and Developmental Biology, University of California Santa Cruz, Santa Cruz, California 95064, USA;
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50
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Nishibuchi G, Machida S, Osakabe A, Murakoshi H, Hiragami-Hamada K, Nakagawa R, Fischle W, Nishimura Y, Kurumizaka H, Tagami H, Nakayama JI. N-terminal phosphorylation of HP1α increases its nucleosome-binding specificity. Nucleic Acids Res 2014; 42:12498-511. [PMID: 25332400 PMCID: PMC4227797 DOI: 10.1093/nar/gku995] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Revised: 09/09/2014] [Accepted: 10/06/2014] [Indexed: 01/08/2023] Open
Abstract
Heterochromatin protein 1 (HP1) is an evolutionarily conserved chromosomal protein that binds to lysine 9-methylated histone H3 (H3K9me), a hallmark of heterochromatin. Although HP1 phosphorylation has been described in several organisms, the biological implications of this modification remain largely elusive. Here we show that HP1's phosphorylation has a critical effect on its nucleosome binding properties. By in vitro phosphorylation assays and conventional chromatography, we demonstrated that casein kinase II (CK2) is the kinase primarily responsible for phosphorylating the N-terminus of human HP1α. Pull-down assays using in vitro-reconstituted nucleosomes showed that unmodified HP1α bound H3K9-methylated and H3K9-unmethylated nucleosomes with comparable affinity, whereas CK2-phosphorylated HP1α showed a high specificity for H3K9me3-modified nucleosomes. Electrophoretic mobility shift assays showed that CK2-mediated phosphorylation diminished HP1α's intrinsic DNA binding, which contributed to its H3K9me-independent nucleosome binding. CK2-mediated phosphorylation had a similar effect on the nucleosome-binding specificity of fly HP1a and S. pombe Swi6. These results suggested that HP1 phosphorylation has an evolutionarily conserved role in HP1's recognition of H3K9me-marked nucleosomes.
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Affiliation(s)
- Gohei Nishibuchi
- Graduate School of Natural Sciences, Nagoya City University, Nagoya 467-8501, Japan
| | - Shinichi Machida
- Laboratory of Structural Biology, Graduate School of Advanced Science and Engineering, Waseda University, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Akihisa Osakabe
- Laboratory of Structural Biology, Graduate School of Advanced Science and Engineering, Waseda University, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Hiromu Murakoshi
- Laboratory of Structural Biology, Graduate School of Advanced Science and Engineering, Waseda University, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Kyoko Hiragami-Hamada
- Laboratory of Chromatin Biochemistry, Max Planck Institute for Biophysical Chemistry, 37077 Göttingen, Germany
| | - Reiko Nakagawa
- Proteomics Support Unit, RIKEN Center for Developmental Biology, Kobe 650-0047, Japan
| | - Wolfgang Fischle
- Laboratory of Chromatin Biochemistry, Max Planck Institute for Biophysical Chemistry, 37077 Göttingen, Germany
| | - Yoshifumi Nishimura
- Graduate School of Medical Life Science, Yokohama City University, 1-7-29, Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan
| | - Hitoshi Kurumizaka
- Laboratory of Structural Biology, Graduate School of Advanced Science and Engineering, Waseda University, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Hideaki Tagami
- Graduate School of Natural Sciences, Nagoya City University, Nagoya 467-8501, Japan
| | - Jun-ichi Nakayama
- Graduate School of Natural Sciences, Nagoya City University, Nagoya 467-8501, Japan
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