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Lai PM, Chan KM. Roles of Histone H2A Variants in Cancer Development, Prognosis, and Treatment. Int J Mol Sci 2024; 25:3144. [PMID: 38542118 PMCID: PMC10969971 DOI: 10.3390/ijms25063144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 02/09/2024] [Accepted: 02/09/2024] [Indexed: 07/16/2024] Open
Abstract
Histones are nuclear proteins essential for packaging genomic DNA and epigenetic gene regulation. Paralogs that can substitute core histones (H2A, H2B, H3, and H4), named histone variants, are constitutively expressed in a replication-independent manner throughout the cell cycle. With specific chaperones, they can be incorporated to chromatin to modify nucleosome stability by modulating interactions with nucleosomal DNA. This allows the regulation of essential fundamental cellular processes for instance, DNA damage repair, chromosomal segregation, and transcriptional regulation. Among all the histone families, histone H2A family has the largest number of histone variants reported to date. Each H2A variant has multiple functions apart from their primary role and some, even be further specialized to perform additional tasks in distinct lineages, such as testis specific shortH2A (sH2A). In the past decades, the discoveries of genetic alterations and mutations in genes encoding H2A variants in cancer had revealed variants' potentiality in driving carcinogenesis. In addition, there is growing evidence that H2A variants may act as novel prognostic indicators or biomarkers for both early cancer detection and therapeutic treatments. Nevertheless, no studies have ever concluded all identified variants in a single report. Here, in this review, we summarize the respective functions for all the 19 mammalian H2A variants and their roles in cancer biology whilst potentiality being used in clinical setting.
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Affiliation(s)
| | - Kui Ming Chan
- Department of Biomedical Sciences, City University of Hong Kong, Hong Kong SAR, China;
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2
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Zhang S, Wang Y, Cui X, Hu J, Kang X, Liu Y, Pan Y. MoNap1, a Nucleosome Assemble Protein 1, Regulates Growth, Development, and Pathogenicity in Magnaporthe oryzae. J Fungi (Basel) 2022; 9:jof9010050. [PMID: 36675871 PMCID: PMC9862126 DOI: 10.3390/jof9010050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 12/24/2022] [Accepted: 12/25/2022] [Indexed: 12/30/2022] Open
Abstract
Nap1 is an evolutionarily conserved protein from yeast to human and is involved in diverse physiological processes, such as nucleosome assembly, histone shuttling between the nucleus and cytoplasm, transcriptional regulation, and the cell cycle regulation. In this paper, we identified nucleosome assemble protein MoNap1 in Magnaporthe oryzae and investigated its function in pathogenicity. Deletion of MoNAP1 resulted in reduced growth and conidiation, decreased appressorium formation rate, and impaired virulence. MoNap1 affects appressorium turgor and utilization of glycogen and lipid droplets. In addition, MoNap1 is involved in the regulation of cell wall, oxidation, and hyperosmotic stress. The subcellular localization experiments showed that MoNap1 is located in the cytoplasm. MoNap1 interacts with MoNbp2, MoClb3, and MoClb1 in M. oryzae. Moreover, deletion of MoNBP2 and MoCLB3 has no effects on vegetative growth, conidiation, and pathogenicity. Transcriptome analysis reveals that MoNAP1 is involved in regulating pathogenicity, the melanin biosynthetic process. Taken together, our results showed that MoNap1 plays a crucial role in growth, conidiation, and pathogenicity of M. oryzae.
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Affiliation(s)
- Shulin Zhang
- Department of Plant Pathology, College of Plant Protection, Anhui Agricultural University, Hefei 230036, China
- Anhui Province Key Laboratory of Crop Integrated Pest Management, Anhui Agricultural University, Hefei 230036, China
- Correspondence: (S.Z.); (Y.P.)
| | - Yu Wang
- Department of Plant Pathology, College of Plant Protection, Anhui Agricultural University, Hefei 230036, China
- Anhui Province Key Laboratory of Crop Integrated Pest Management, Anhui Agricultural University, Hefei 230036, China
| | - Xinyue Cui
- Department of Plant Pathology, College of Plant Protection, Anhui Agricultural University, Hefei 230036, China
- Anhui Province Key Laboratory of Crop Integrated Pest Management, Anhui Agricultural University, Hefei 230036, China
| | - Jinmei Hu
- Department of Plant Pathology, College of Plant Protection, Anhui Agricultural University, Hefei 230036, China
- Anhui Province Key Laboratory of Crop Integrated Pest Management, Anhui Agricultural University, Hefei 230036, China
| | - Xiaoru Kang
- Department of Plant Pathology, College of Plant Protection, Anhui Agricultural University, Hefei 230036, China
- Anhui Province Key Laboratory of Crop Integrated Pest Management, Anhui Agricultural University, Hefei 230036, China
| | - Yuyan Liu
- Department of Plant Pathology, College of Plant Protection, Anhui Agricultural University, Hefei 230036, China
- Anhui Province Key Laboratory of Crop Integrated Pest Management, Anhui Agricultural University, Hefei 230036, China
| | - Yuemin Pan
- Department of Plant Pathology, College of Plant Protection, Anhui Agricultural University, Hefei 230036, China
- Anhui Province Key Laboratory of Crop Integrated Pest Management, Anhui Agricultural University, Hefei 230036, China
- Correspondence: (S.Z.); (Y.P.)
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Di Mambro A, Esposito M. Thirty years of SET/TAF1β/I2PP2A: from the identification of the biological functions to its implications in cancer and Alzheimer's disease. Biosci Rep 2022; 42:BSR20221280. [PMID: 36345878 PMCID: PMC9679398 DOI: 10.1042/bsr20221280] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 10/17/2022] [Accepted: 11/07/2022] [Indexed: 10/29/2023] Open
Abstract
The gene encoding for the protein SE translocation (SET) was identified for the first time 30 years ago as part of a chromosomal translocation in a patient affected by leukemia. Since then, accumulating evidence have linked overexpression of SET, aberrant SET splicing, and cellular localization to cancer progression and development of neurodegenerative tauopathies such as Alzheimer's disease. Molecular biology tools, such as targeted genetic deletion, and pharmacological approaches based on SET antagonist peptides, have contributed to unveil the molecular functions of SET and its implications in human pathogenesis. In this review, we provide an overview of the functions of SET as inhibitor of histone and non-histone protein acetylation and as a potent endogenous inhibitor of serine-threonine phosphatase PP2A. We discuss the role of SET in multiple cellular processes, including chromatin remodelling and gene transcription, DNA repair, oxidative stress, cell cycle, apoptosis cell migration and differentiation. We review the molecular mechanisms linking SET dysregulation to tumorigenesis and discuss how SET commits neurons to progressive cell death in Alzheimer's disease, highlighting the rationale of exploiting SET as a therapeutic target for cancer and neurodegenerative tauopathies.
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Affiliation(s)
- Antonella Di Mambro
- The Centre for Integrated Research in Life and Health Sciences, School of Health and Life Science, University of Roehampton, London, U.K
| | - Maria Teresa Esposito
- The Centre for Integrated Research in Life and Health Sciences, School of Health and Life Science, University of Roehampton, London, U.K
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Herchenröther A, Wunderlich TM, Lan J, Hake SB. Spotlight on histone H2A variants: From B to X to Z. Semin Cell Dev Biol 2022; 135:3-12. [PMID: 35365397 DOI: 10.1016/j.semcdb.2022.03.025] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 03/18/2022] [Accepted: 03/20/2022] [Indexed: 12/30/2022]
Abstract
Chromatin, the functional organization of DNA with histone proteins in eukaryotic nuclei, is the tightly-regulated template for several biological processes, such as transcription, replication, DNA damage repair, chromosome stability and sister chromatid segregation. In order to achieve a reversible control of local chromatin structure and DNA accessibility, various interconnected mechanisms have evolved. One of such processes includes the deposition of functionally-diverse variants of histone proteins into nucleosomes, the building blocks of chromatin. Among core histones, the family of H2A histone variants exhibits the largest number of members and highest sequence-divergence. In this short review, we report and discuss recent discoveries concerning the biological functions of the animal histone variants H2A.B, H2A.X and H2A.Z and how dysregulation or mutation of the latter impacts the development of disease.
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Affiliation(s)
| | - Tim M Wunderlich
- Institute for Genetics, Justus Liebig University, 35390 Giessen, Germany
| | - Jie Lan
- Institute for Genetics, Justus Liebig University, 35390 Giessen, Germany.
| | - Sandra B Hake
- Institute for Genetics, Justus Liebig University, 35390 Giessen, Germany.
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Guo N, Zheng D, Sun J, Lv J, Wang S, Fang Y, Zhao Z, Zeng S, Guo Q, Tong J, Wang Z. NAP1L5 Promotes Nucleolar Hypertrophy and Is Required for Translation Activation During Cardiomyocyte Hypertrophy. Front Cardiovasc Med 2021; 8:791501. [PMID: 34977198 PMCID: PMC8718910 DOI: 10.3389/fcvm.2021.791501] [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: 10/08/2021] [Accepted: 11/29/2021] [Indexed: 11/13/2022] Open
Abstract
Pathological growth of cardiomyocytes during hypertrophy is characterized by excess protein synthesis; however, the regulatory mechanism remains largely unknown. Using a neonatal rat ventricular myocytes (NRVMs) model, here we find that the expression of nucleosome assembly protein 1 like 5 (Nap1l5) is upregulated in phenylephrine (PE)-induced hypertrophy. Knockdown of Nap1l5 expression by siRNA significantly blocks cell size enlargement and pathological gene induction after PE treatment. In contrast, Adenovirus-mediated Nap1l5 overexpression significantly aggravates the pro-hypertrophic effects of PE on NRVMs. RNA-seq analysis reveals that Nap1l5 knockdown reverses the pro-hypertrophic transcriptome reprogramming after PE treatment. Whereas, immune response is dominantly enriched in the upregulated genes, oxidative phosphorylation, cardiac muscle contraction and ribosome-related pathways are remarkably enriched in the down-regulated genes. Although Nap1l5-mediated gene regulation is correlated with PRC2 and PRC1, Nap1l5 does not directly alter the levels of global histone methylations at K4, K9, K27 or K36. However, puromycin incorporation assay shows that Nap1l5 is both necessary and sufficient to promote protein synthesis in cardiomyocyte hypertrophy. This is attributable to a direct regulation of nucleolus hypertrophy and subsequent ribosome assembly. Our findings demonstrate a previously unrecognized role of Nap1l5 in translation control during cardiac hypertrophy.
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Affiliation(s)
- Ningning Guo
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, China
- Shenzhen Key Laboratory of Cardiovascular Disease, Fuwai Hospital, Chinese Academy of Medical Sciences, Shenzhen, China
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Disease, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Di Zheng
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Jiaxin Sun
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Jian Lv
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, China
- Shenzhen Key Laboratory of Cardiovascular Disease, Fuwai Hospital, Chinese Academy of Medical Sciences, Shenzhen, China
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Disease, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Shun Wang
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Yu Fang
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, China
- Shenzhen Key Laboratory of Cardiovascular Disease, Fuwai Hospital, Chinese Academy of Medical Sciences, Shenzhen, China
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Disease, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Zhenyi Zhao
- Shenzhen Key Laboratory of Cardiovascular Disease, Fuwai Hospital, Chinese Academy of Medical Sciences, Shenzhen, China
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Disease, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
- Health Science Center, School of Pharmacy, Shenzhen University, Shenzhen, China
| | - Sai Zeng
- Shenzhen Key Laboratory of Cardiovascular Disease, Fuwai Hospital, Chinese Academy of Medical Sciences, Shenzhen, China
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Disease, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Qiuxiao Guo
- Shenzhen Key Laboratory of Cardiovascular Disease, Fuwai Hospital, Chinese Academy of Medical Sciences, Shenzhen, China
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Disease, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Jingjing Tong
- School of Life Sciences, Central China Normal University, Wuhan, China
- *Correspondence: Jingjing Tong
| | - Zhihua Wang
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, China
- Shenzhen Key Laboratory of Cardiovascular Disease, Fuwai Hospital, Chinese Academy of Medical Sciences, Shenzhen, China
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Disease, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
- Zhihua Wang
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Mutual dependency between lncRNA LETN and protein NPM1 in controlling the nucleolar structure and functions sustaining cell proliferation. Cell Res 2021; 31:664-683. [PMID: 33432115 PMCID: PMC8169757 DOI: 10.1038/s41422-020-00458-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Accepted: 11/30/2020] [Indexed: 02/06/2023] Open
Abstract
Fundamental processes such as ribosomal RNA synthesis and chromatin remodeling take place in the nucleolus, which is hyperactive in fast-proliferating cells. The sophisticated regulatory mechanism underlying the dynamic nucleolar structure and functions is yet to be fully explored. The present study uncovers the mutual functional dependency between a previously uncharacterized human long non-coding RNA, which we renamed LETN, and a key nucleolar protein, NPM1. Specifically, being upregulated in multiple types of cancer, LETN resides in the nucleolus via direct binding with NPM1. LETN plays a critical role in facilitating the formation of NPM1 pentamers, which are essential building blocks of the nucleolar granular component and control the nucleolar functions. Repression of LETN or NPM1 led to similar and profound changes of the nucleolar morphology and arrest of the nucleolar functions, which led to proliferation inhibition of human cancer cells and neural progenitor cells. Interestingly, this inter-dependency between LETN and NPM1 is associated with the evolutionarily new variations of NPM1 and the coincidental emergence of LETN in higher primates. We propose that this human-specific protein-lncRNA axis renders an additional yet critical layer of regulation with high physiological relevance in both cancerous and normal developmental processes that require hyperactive nucleoli.
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Lai X, Blanc-Mathieu R, GrandVuillemin L, Huang Y, Stigliani A, Lucas J, Thévenon E, Loue-Manifel J, Turchi L, Daher H, Brun-Hernandez E, Vachon G, Latrasse D, Benhamed M, Dumas R, Zubieta C, Parcy F. The LEAFY floral regulator displays pioneer transcription factor properties. MOLECULAR PLANT 2021; 14:829-837. [PMID: 33684542 DOI: 10.1016/j.molp.2021.03.004] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 01/28/2021] [Accepted: 03/02/2021] [Indexed: 05/23/2023]
Abstract
Pioneer transcription factors (TFs) are a special category of TFs with the capacity to bind to closed chromatin regions in which DNA is wrapped around histones and may be highly methylated. Subsequently, pioneer TFs are able to modify the chromatin state to initiate gene expression. In plants, LEAFY (LFY) is a master floral regulator and has been suggested to act as a pioneer TF in Arabidopsis. Here, we demonstrate that LFY is able to bind both methylated and non-methylated DNA using a combination of in vitro genome-wide binding experiments and structural modeling. Comparisons between regions bound by LFY in vivo and chromatin accessibility data suggest that a subset of LFY bound regions is occupied by nucleosomes. We confirm that LFY is able to bind nucleosomal DNA in vitro using reconstituted nucleosomes. Finally, we show that constitutive LFY expression in seedling tissues is sufficient to induce chromatin accessibility in the LFY direct target genes APETALA1 and AGAMOUS. Taken together, our study suggests that LFY possesses key pioneer TF features that contribute to launching the floral gene expression program.
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Affiliation(s)
- Xuelei Lai
- Laboratoire Physiologie Cellulaire et Végétale, Université Grenoble Alpes, CNRS, CEA, INRAE, IRIG-DBSCI-LPCV, 17 avenue des martyrs, 38054, Grenoble, France
| | - Romain Blanc-Mathieu
- Laboratoire Physiologie Cellulaire et Végétale, Université Grenoble Alpes, CNRS, CEA, INRAE, IRIG-DBSCI-LPCV, 17 avenue des martyrs, 38054, Grenoble, France
| | - Loïc GrandVuillemin
- Laboratoire Physiologie Cellulaire et Végétale, Université Grenoble Alpes, CNRS, CEA, INRAE, IRIG-DBSCI-LPCV, 17 avenue des martyrs, 38054, Grenoble, France
| | - Ying Huang
- Université Paris-Saclay, CNRS, INRAE, Université d'Evry, Institute of Plant Sciences Paris-Saclay (IPS2), 91405, Orsay, France
| | - Arnaud Stigliani
- Laboratoire Physiologie Cellulaire et Végétale, Université Grenoble Alpes, CNRS, CEA, INRAE, IRIG-DBSCI-LPCV, 17 avenue des martyrs, 38054, Grenoble, France; The Bioinformatics Centre, Department of Biology and Biotech and Research Innovation Centre, University of Copenhagen, Ole Maaløes Vej 5, DK2200 Copenhagen N, Denmark
| | - Jérémy Lucas
- Laboratoire Physiologie Cellulaire et Végétale, Université Grenoble Alpes, CNRS, CEA, INRAE, IRIG-DBSCI-LPCV, 17 avenue des martyrs, 38054, Grenoble, France
| | - Emmanuel Thévenon
- Laboratoire Physiologie Cellulaire et Végétale, Université Grenoble Alpes, CNRS, CEA, INRAE, IRIG-DBSCI-LPCV, 17 avenue des martyrs, 38054, Grenoble, France
| | - Jeanne Loue-Manifel
- Laboratoire Physiologie Cellulaire et Végétale, Université Grenoble Alpes, CNRS, CEA, INRAE, IRIG-DBSCI-LPCV, 17 avenue des martyrs, 38054, Grenoble, France; Laboratoire Reproduction et Développement des Plantes, Université de Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRA, 69342 Lyon, France
| | - Laura Turchi
- Laboratoire Physiologie Cellulaire et Végétale, Université Grenoble Alpes, CNRS, CEA, INRAE, IRIG-DBSCI-LPCV, 17 avenue des martyrs, 38054, Grenoble, France
| | - Hussein Daher
- Laboratoire Physiologie Cellulaire et Végétale, Université Grenoble Alpes, CNRS, CEA, INRAE, IRIG-DBSCI-LPCV, 17 avenue des martyrs, 38054, Grenoble, France; Institut de Biologie Structurale, Université Grenoble Alpes, CEA, CNRS, Grenoble, France
| | - Eugenia Brun-Hernandez
- Laboratoire Physiologie Cellulaire et Végétale, Université Grenoble Alpes, CNRS, CEA, INRAE, IRIG-DBSCI-LPCV, 17 avenue des martyrs, 38054, Grenoble, France
| | - Gilles Vachon
- Laboratoire Physiologie Cellulaire et Végétale, Université Grenoble Alpes, CNRS, CEA, INRAE, IRIG-DBSCI-LPCV, 17 avenue des martyrs, 38054, Grenoble, France
| | - David Latrasse
- Université Paris-Saclay, CNRS, INRAE, Université d'Evry, Institute of Plant Sciences Paris-Saclay (IPS2), 91405, Orsay, France
| | - Moussa Benhamed
- Université Paris-Saclay, CNRS, INRAE, Université d'Evry, Institute of Plant Sciences Paris-Saclay (IPS2), 91405, Orsay, France; Université de Paris, Institute of Plant Sciences Paris-Saclay (IPS2), 75006 Paris, France
| | - Renaud Dumas
- Laboratoire Physiologie Cellulaire et Végétale, Université Grenoble Alpes, CNRS, CEA, INRAE, IRIG-DBSCI-LPCV, 17 avenue des martyrs, 38054, Grenoble, France
| | - Chloe Zubieta
- Laboratoire Physiologie Cellulaire et Végétale, Université Grenoble Alpes, CNRS, CEA, INRAE, IRIG-DBSCI-LPCV, 17 avenue des martyrs, 38054, Grenoble, France
| | - François Parcy
- Laboratoire Physiologie Cellulaire et Végétale, Université Grenoble Alpes, CNRS, CEA, INRAE, IRIG-DBSCI-LPCV, 17 avenue des martyrs, 38054, Grenoble, France.
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Histone variant H2A.B-H2B dimers are spontaneously exchanged with canonical H2A-H2B in the nucleosome. Commun Biol 2021; 4:191. [PMID: 33580188 PMCID: PMC7881002 DOI: 10.1038/s42003-021-01707-z] [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: 08/21/2020] [Accepted: 01/11/2021] [Indexed: 01/07/2023] Open
Abstract
H2A.B is an evolutionarily distant histone H2A variant that accumulates on DNA repair sites, DNA replication sites, and actively transcribing regions in genomes. In cells, H2A.B exchanges rapidly in chromatin, but the mechanism has remained enigmatic. In the present study, we found that the H2A.B-H2B dimer incorporated within the nucleosome exchanges with the canonical H2A-H2B dimer without assistance from additional factors, such as histone chaperones and nucleosome remodelers. High-speed atomic force microscopy revealed that the H2A.B nucleosome, but not the canonical H2A nucleosome, transiently forms an intermediate "open conformation", in which two H2A.B-H2B dimers may be detached from the H3-H4 tetramer and bind to the DNA regions near the entry/exit sites. Mutational analyses revealed that the H2A.B C-terminal region is responsible for the adoption of the open conformation and the H2A.B-H2B exchange in the nucleosome. These findings provide mechanistic insights into the histone exchange of the H2A.B nucleosome.
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Martire S, Banaszynski LA. The roles of histone variants in fine-tuning chromatin organization and function. Nat Rev Mol Cell Biol 2020; 21:522-541. [PMID: 32665685 PMCID: PMC8245300 DOI: 10.1038/s41580-020-0262-8] [Citation(s) in RCA: 194] [Impact Index Per Article: 48.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/28/2020] [Indexed: 12/15/2022]
Abstract
Histones serve to both package and organize DNA within the nucleus. In addition to histone post-translational modification and chromatin remodelling complexes, histone variants contribute to the complexity of epigenetic regulation of the genome. Histone variants are characterized by a distinct protein sequence and a selection of designated chaperone systems and chromatin remodelling complexes that regulate their localization in the genome. In addition, histone variants can be enriched with specific post-translational modifications, which in turn can provide a scaffold for recruitment of variant-specific interacting proteins to chromatin. Thus, through these properties, histone variants have the capacity to endow specific regions of chromatin with unique character and function in a regulated manner. In this Review, we provide an overview of recent advances in our understanding of the contribution of histone variants to chromatin function in mammalian systems. First, we discuss new molecular insights into chaperone-mediated histone variant deposition. Next, we discuss mechanisms by which histone variants influence chromatin properties such as nucleosome stability and the local chromatin environment both through histone variant sequence-specific effects and through their role in recruiting different chromatin-associated complexes. Finally, we focus on histone variant function in the context of both embryonic development and human disease, specifically developmental syndromes and cancer.
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Affiliation(s)
- Sara Martire
- Green Center for Reproductive Biology Sciences, Department of Obstetrics and Gynecology, Children's Research Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Laura A Banaszynski
- Green Center for Reproductive Biology Sciences, Department of Obstetrics and Gynecology, Children's Research Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA.
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Histone H2A variants alpha1-extension helix directs RNF168-mediated ubiquitination. Nat Commun 2020; 11:2462. [PMID: 32424115 PMCID: PMC7235047 DOI: 10.1038/s41467-020-16307-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Accepted: 04/27/2020] [Indexed: 01/28/2023] Open
Abstract
Histone ubiquitination plays an important role in the DNA damage response (DDR) pathway. RNF168 catalyzes H2A and H2AX ubiquitination on lysine 13/15 (K13/K15) upon DNA damage and promotes the accrual of downstream repair factors at damaged chromatin. Here, we report that RNF168 ubiquitinates the non-canonical H2A variants H2AZ and macroH2A1/2 at the divergent N-terminal tail lysine residue. In addition to their evolutionarily conserved nucleosome acidic patch, we identify the positively charged alpha1-extension helix as essential for RNF168-mediated ubiquitination of H2A variants. Moreover, mutation of the RNF168 UMI (UIM- and MIU-related UBD) hydrophilic acidic residues abolishes RNF168-mediated ubiquitination as well as 53BP1 and BRCA1 ionizing radiation-induced foci formation. Our results reveal a juxtaposed bipartite electrostatic interaction utilized by the nucleosome to direct RNF168 orientation towards the target lysine residues in proximity to the H2A alpha1-extension helix, which plays an important role in the DDR pathway.
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Short Histone H2A Variants: Small in Stature but not in Function. Cells 2020; 9:cells9040867. [PMID: 32252453 PMCID: PMC7226823 DOI: 10.3390/cells9040867] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Revised: 03/24/2020] [Accepted: 03/31/2020] [Indexed: 12/19/2022] Open
Abstract
The dynamic packaging of DNA into chromatin regulates all aspects of genome function by altering the accessibility of DNA and by providing docking pads to proteins that copy, repair and express the genome. Different epigenetic-based mechanisms have been described that alter the way DNA is organised into chromatin, but one fundamental mechanism alters the biochemical composition of a nucleosome by substituting one or more of the core histones with their variant forms. Of the core histones, the largest number of histone variants belong to the H2A class. The most divergent class is the designated “short H2A variants” (H2A.B, H2A.L, H2A.P and H2A.Q), so termed because they lack a H2A C-terminal tail. These histone variants appeared late in evolution in eutherian mammals and are lineage-specific, being expressed in the testis (and, in the case of H2A.B, also in the brain). To date, most information about the function of these peculiar histone variants has come from studies on the H2A.B and H2A.L family in mice. In this review, we describe their unique protein characteristics, their impact on chromatin structure, and their known functions plus other possible, even non-chromatin, roles in an attempt to understand why these peculiar histone variants evolved in the first place.
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Liu Y, Xu L, Xie C, Hong J, Li F, Ruan K, Chen J, Wu J, Shi Y. Structural Insights into ceNAP1 Chaperoning Activity toward ceH2A-H2B. Structure 2019; 27:1798-1810.e3. [DOI: 10.1016/j.str.2019.10.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2019] [Revised: 09/11/2019] [Accepted: 09/30/2019] [Indexed: 10/25/2022]
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Zhang Y, Tao H, Huang SY. Dynamics and Mechanisms in the Recruitment and Transference of Histone Chaperone CIA/ASF1. Int J Mol Sci 2019; 20:ijms20133325. [PMID: 31284555 PMCID: PMC6651421 DOI: 10.3390/ijms20133325] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 06/21/2019] [Accepted: 06/28/2019] [Indexed: 12/14/2022] Open
Abstract
The recruitment and transference of proteins through protein-protein interactions is a general process involved in various biological functions in cells. Despite the importance of this general process, the dynamic mechanism of how proteins are recruited and transferred from one interacting partner to another remains unclear. In this study, we investigated the dynamic mechanisms of recruitment and translocation of histone chaperone CIA/ASF1 for nucleosome disassembly by exploring the conformational space and the free energy profile of unbound DBD(CCG1) and CIA/ASF1-bound DBD(CCG1) systems through extensive molecular dynamics simulations. It was found that there exists three metastable conformational states for DBD(CCG1), an unbound closed state, a CIA/ASF1-bound half-open state, and an open state. The free energy landscape shows that the closed state and the half-open state are separated by a high free energy barrier, while the half-open state and the open state are connected with a moderate free energy increase. The high free energy barrier between the closed and half-open states explains why DBD(CCG1) can recruit CIA/ASF1 and remain in the binding state during the transportation. In addition, the asymmetric binding of CIA/ASF1 on DBD(CCG1) allows DBD(CCG1) to adopt the open state by moving one of its two domains, such that the exposed domain of DBD(CCG1) is able to recognize the acetylated histone H4 tails. As such, CIA/ASF1 has a chance to translocate from DBD(CCG1) to histone, which is also facilitated by the moderate energy increase from the bound half-open state to the open state of DBD(CCG1). These findings suggest that the recruitment and transference of histone chaperone CIA/ASF1 is highly favored by its interaction with DBD(CCG1) via conformational selection and asymmetric binding, which may represent a general mechanism of similar biological processes.
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Affiliation(s)
- Yanjun Zhang
- School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Huanyu Tao
- School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Sheng-You Huang
- School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China.
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Reddy D, Bhattacharya S, Jani V, Sonavane U, Joshi R, Gupta S. Biochemical and Biophysical Characterisation of Higher Oligomeric Structure of Rat Nucleosome Assembly Protein 1. Protein J 2018; 37:58-69. [PMID: 29209909 DOI: 10.1007/s10930-017-9751-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Nucleosome assembly protein 1 (NAP1) is a histone chaperone that exchanges histone H2A-H2B dimer from chromatin templates. Studies with yeast NAP1 (yNAP1) have revealed its existence as multiple oligomeric species in solution. Here, rat NAP1 (rNAP1), which is 98% identical to the human NAP1 (hNAP1) was used as a model to characterize the oligomeric structures of this protein in higher eukaryotes. Gel filtration chromatography and Dynamic light scattering of recombinant rNAP1 indicated that the protein exists as a complex mixture of multimeric species even at 500 mM ionic strength. The solution-state complexity remains unchanged even at higher ionic strengths. Equilibrium unfolding (ΔG 14.6 kcal mol- 1) shows that rNAP1, both dimeric and oligomeric, follow the two-state model of unfolding with no detectable intermediates. Homology modelling suggests that rat and yeast NAP1 share an overall similar structure with conserved domains. However, dissimilar substitutions like threonine and lysine with glycine in the β-hairpin involved in oligomerization, possibly leads to the observed differences in the oligomerization propensity of the two proteins. Molecular dynamic simulation (MDS) of the two structures also revealed that rNAP1 dimer is more stable owing to the extensive hydrogen bonding in comparison to yNAP1. Further, in vitro kinase assay showed that the phosphorylation of rNAP1 favors oligomerization with no effect on its histone binding capacity. Our results clearly suggest that there are differences in the in-solution behavior of rNAP1 compared to yNAP1 which may have in vivo functional implications for the regulation of these complexes during chromatin assembly and rearrangement.
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Affiliation(s)
- Divya Reddy
- Epigenetics and Chromatin Biology Group, Gupta Lab, Cancer Research Institute, Advanced Centre for Treatment, Research and Education in Cancer (ACTREC), Tata Memorial Centre, Kharghar, Navi Mumbai, Maharashtra, 410210, India.,Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai, Maharashtra, 400085, India
| | - Saikat Bhattacharya
- Epigenetics and Chromatin Biology Group, Gupta Lab, Cancer Research Institute, Advanced Centre for Treatment, Research and Education in Cancer (ACTREC), Tata Memorial Centre, Kharghar, Navi Mumbai, Maharashtra, 410210, India.,Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai, Maharashtra, 400085, India.,Workman Lab, Stowers Institute for Medical Research, 1000 E 50th Street, Kansas City, MO, 64110, USA
| | - Vinod Jani
- Bioinformatics Group, Centre for Development of Advanced Computing (C-DAC), University of Pune Campus, Pune, Maharashtra, 411007, India
| | - Uddhavesh Sonavane
- Bioinformatics Group, Centre for Development of Advanced Computing (C-DAC), University of Pune Campus, Pune, Maharashtra, 411007, India
| | - Rajendra Joshi
- Bioinformatics Group, Centre for Development of Advanced Computing (C-DAC), University of Pune Campus, Pune, Maharashtra, 411007, India
| | - Sanjay Gupta
- Epigenetics and Chromatin Biology Group, Gupta Lab, Cancer Research Institute, Advanced Centre for Treatment, Research and Education in Cancer (ACTREC), Tata Memorial Centre, Kharghar, Navi Mumbai, Maharashtra, 410210, India. .,Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai, Maharashtra, 400085, India.
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15
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The histone chaperone NAP1L3 is required for haematopoietic stem cell maintenance and differentiation. Sci Rep 2018; 8:11202. [PMID: 30046127 PMCID: PMC6060140 DOI: 10.1038/s41598-018-29518-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Accepted: 07/12/2018] [Indexed: 01/04/2023] Open
Abstract
Nucleosome assembly proteins (NAPs) are histone chaperones with an important role in chromatin structure and epigenetic regulation of gene expression. We find that high gene expression levels of mouse Nap1l3 are restricted to haematopoietic stem cells (HSCs) in mice. Importantly, with shRNA or CRISPR-Cas9 mediated loss of function of mouse Nap1l3 and with overexpression of the gene, the number of colony-forming cells and myeloid progenitor cells in vitro are reduced. This manifests as a striking decrease in the number of HSCs, which reduces their reconstituting activities in vivo. Downregulation of human NAP1L3 in umbilical cord blood (UCB) HSCs impairs the maintenance and proliferation of HSCs both in vitro and in vivo. NAP1L3 downregulation in UCB HSCs causes an arrest in the G0 phase of cell cycle progression and induces gene expression signatures that significantly correlate with downregulation of gene sets involved in cell cycle regulation, including E2F and MYC target genes. Moreover, we demonstrate that HOXA3 and HOXA5 genes are markedly upregulated when NAP1L3 is suppressed in UCB HSCs. Taken together, our findings establish an important role for NAP1L3 in HSC homeostasis and haematopoietic differentiation.
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16
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Bayarkhangai B, Noureldin S, Yu L, Zhao N, Gu Y, Xu H, Guo C. A comprehensive and perspective view of oncoprotein SET in cancer. Cancer Med 2018; 7:3084-3094. [PMID: 29749127 PMCID: PMC6051184 DOI: 10.1002/cam4.1526] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2017] [Revised: 03/25/2018] [Accepted: 04/05/2018] [Indexed: 12/16/2022] Open
Abstract
SET is a multifunctional oncoprotein which is ubiquitously expressed in all kinds of cells. The SET protein participates in many cellular processes including cell cycle, cell migration, apoptosis, transcription, and DNA repair. Accumulating evidence demonstrates that the expression and activity of SET correlate with cancer occurrence, metastasis, and prognosis. Therefore, the SET protein is regarded as a potential target for cancer therapy and several inhibitors are being developed for clinical use. Herein, we comprehensively review the physiological and pathological functions of SET as well as its structure-function relationship. Additionally, the regulatory mechanisms of SET at both transcriptional and posttranslational levels are also discussed.
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Affiliation(s)
- Buuvee Bayarkhangai
- State Key of Natural Medicine, China Pharmaceutical University, Nanjing, China
| | - Suzan Noureldin
- State Key of Natural Medicine, China Pharmaceutical University, Nanjing, China
| | - Liting Yu
- State Key of Natural Medicine, China Pharmaceutical University, Nanjing, China
| | - Na Zhao
- State Key of Natural Medicine, China Pharmaceutical University, Nanjing, China
| | - Yaru Gu
- State Key of Natural Medicine, China Pharmaceutical University, Nanjing, China
| | - Hanmei Xu
- State Key of Natural Medicine, China Pharmaceutical University, Nanjing, China
| | - Changying Guo
- State Key of Natural Medicine, China Pharmaceutical University, Nanjing, China
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17
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Quénet D. Histone Variants and Disease. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2018; 335:1-39. [DOI: 10.1016/bs.ircmb.2017.07.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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18
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Assembly and remodeling of viral DNA and RNA replicons regulated by cellular molecular chaperones. Biophys Rev 2017; 10:445-452. [PMID: 29170971 DOI: 10.1007/s12551-017-0333-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2017] [Accepted: 11/07/2017] [Indexed: 12/12/2022] Open
Abstract
A variety of cellular reactions mediated by interactions among proteins and nucleic acids requires a series of proteins called molecular chaperones. The viral genome encodes relatively few kinds of viral proteins and, therefore, host-derived cellular factors are required for virus proliferation. Here we discuss those cellular proteins known as molecular chaperones, which are essential for the assembly of functional viral DNA/RNA replicons. The function of these molecular chaperones in the cellular context is also discussed.
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19
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NAP1L1 regulates NF-κB signaling pathway acting on anti-apoptotic Mcl-1 gene expression. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2017; 1864:1759-1768. [DOI: 10.1016/j.bbamcr.2017.06.021] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Revised: 06/28/2017] [Accepted: 06/30/2017] [Indexed: 01/20/2023]
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20
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Lee J, Lee TH. Single-Molecule Investigations on Histone H2A-H2B Dynamics in the Nucleosome. Biochemistry 2017; 56:977-985. [PMID: 28128545 DOI: 10.1021/acs.biochem.6b01252] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Nucleosomes impose physical barriers to DNA-templated processes, playing important roles in eukaryotic gene regulation. DNA is packaged into nucleosomes by histone proteins mainly through strong electrostatic interactions that can be modulated by various post-translational histone modifications. Investigating the dynamics of histone dissociation from the nucleosome and how it is altered upon histone modifications is important for understanding eukaryotic gene regulation mechanisms. In particular, histone H2A-H2B dimer displacement in the nucleosome is one of the most important and earliest steps of histone dissociation. Two conflicting hypotheses on the requirement for dimer displacement are that nucleosomal DNA needs to be unwrapped before a dimer can displace and that a dimer can displace without DNA unwrapping. In order to test the hypotheses, we employed three-color single-molecule FRET and monitored in a time-resolved manner the early kinetics of H2A-H2B dimer dissociation triggered by high salt concentration and by histone chaperone Nap1. The results reveal that dimer displacement requires DNA unwrapping in the vast majority of the nucleosomes in the salt-induced case, while dimer displacement precedes DNA unwrapping in >60% of the nucleosomes in the Nap1-mediated case. We also found that acetylation at histone H4K16 or H3K56 affects the kinetics of Nap1-mediated dimer dissociation and facilitates the process both kinetically and thermodynamically. On the basis of these results, we suggest a mechanism by which histone chaperone facilitates H2A-H2B dimer displacement from the histone core without requiring another factor to unwrap the nucleosomal DNA.
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Affiliation(s)
- Jaehyoun Lee
- Department of Chemistry, The Pennsylvania State University , University Park, Pennsylvania 16802, United States
| | - Tae-Hee Lee
- Department of Chemistry, The Pennsylvania State University , University Park, Pennsylvania 16802, United States
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21
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Buschbeck M, Hake SB. Variants of core histones and their roles in cell fate decisions, development and cancer. Nat Rev Mol Cell Biol 2017; 18:299-314. [DOI: 10.1038/nrm.2016.166] [Citation(s) in RCA: 217] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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22
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Regulation of Cellular Dynamics and Chromosomal Binding Site Preference of Linker Histones H1.0 and H1.X. Mol Cell Biol 2016; 36:2681-2696. [PMID: 27528617 DOI: 10.1128/mcb.00200-16] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2016] [Accepted: 08/08/2016] [Indexed: 01/01/2023] Open
Abstract
Linker histones play important roles in the genomic organization of mammalian cells. Of the linker histone variants, H1.X shows the most dynamic behavior in the nucleus. Recent research has suggested that the linker histone variants H1.X and H1.0 have different chromosomal binding site preferences. However, it remains unclear how the dynamics and binding site preferences of linker histones are determined. Here, we biochemically demonstrated that the DNA/nucleosome and histone chaperone binding activities of H1.X are significantly lower than those of other linker histones. This explains why H1.X moves more rapidly than other linker histones in vivo Domain swapping between H1.0 and H1.X suggests that the globular domain (GD) and C-terminal domain (CTD) of H1.X independently contribute to the dynamic behavior of H1.X. Our results also suggest that the N-terminal domain (NTD), GD, and CTD cooperatively determine the preferential binding sites, and the contribution of each domain for this determination is different depending on the target genes. We also found that linker histones accumulate in the nucleoli when the nucleosome binding activities of the GDs are weak. Our results contribute to understanding the molecular mechanisms of dynamic behaviors, binding site selection, and localization of linker histones.
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23
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Gupta N, Thakker S, Verma SC. KSHV encoded LANA recruits Nucleosome Assembly Protein NAP1L1 for regulating viral DNA replication and transcription. Sci Rep 2016; 6:32633. [PMID: 27599637 PMCID: PMC5013526 DOI: 10.1038/srep32633] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Accepted: 08/11/2016] [Indexed: 11/17/2022] Open
Abstract
The establishment of latency is an essential for lifelong persistence and pathogenesis of Kaposi’s sarcoma-associated herpesvirus (KSHV). Latency-associated nuclear antigen (LANA) is the most abundantly expressed protein during latency and is important for viral genome replication and transcription. Replication-coupled nucleosome assembly is a major step in packaging the newly synthesized DNA into chromatin, but the mechanism of KSHV genome chromatinization post-replication is not understood. Here, we show that nucleosome assembly protein 1-like protein 1 (NAP1L1) associates with LANA. Our binding assays revealed an association of LANA with NAP1L1 in KSHV-infected cells, which binds through its amino terminal domain. Association of these proteins confirmed their localization in specific nuclear compartments of the infected cells. Chromatin immunoprecipitation assays from NAP1L1-depleted cells showed LANA-mediated recruitment of NAP1L1 at the terminal repeat (TR) region of the viral genome. Presence of NAP1L1 stimulated LANA-mediated DNA replication and persistence of a TR-containing plasmid. Depletion of NAP1L1 led to a reduced nucleosome positioning on the viral genome. Furthermore, depletion of NAP1L1 increased the transcription of viral lytic genes and overexpression decreased the promoter activities of LANA-regulated genes. These results confirmed that LANA recruitment of NAP1L1 helps in assembling nucleosome for the chromatinization of newly synthesized viral DNA.
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Affiliation(s)
- Namrata Gupta
- Department of Microbiology and Immunology, School of Medicine, University of Nevada, Reno, NV 89557, USA
| | - Suhani Thakker
- Department of Microbiology and Immunology, School of Medicine, University of Nevada, Reno, NV 89557, USA
| | - Subhash C Verma
- Department of Microbiology and Immunology, School of Medicine, University of Nevada, Reno, NV 89557, USA
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24
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Aizawa M, Sugimoto N, Watanabe S, Yoshida K, Fujita M. Nucleosome assembly and disassembly activity of GRWD1, a novel Cdt1-binding protein that promotes pre-replication complex formation. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2016; 1863:2739-2748. [PMID: 27552915 DOI: 10.1016/j.bbamcr.2016.08.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Revised: 08/12/2016] [Accepted: 08/16/2016] [Indexed: 01/08/2023]
Abstract
GRWD1 was previously identified as a novel Cdt1-binding protein that possesses histone-binding and nucleosome assembly activities and promotes MCM loading, probably by maintaining chromatin openness at replication origins. However, the molecular mechanisms underlying these activities remain unknown. We prepared reconstituted mononucleosomes from recombinant histones and a DNA fragment containing a nucleosome positioning sequence, and investigated the effects of GRWD1 on them. GRWD1 could disassemble these preformed mononucleosomes in vitro in an ATP-independent manner. Thus, our data suggest that GRWD1 facilitates removal of H2A-H2B dimers from nucleosomes, resulting in formation of hexasomes. The activity was compromised by deletion of the acidic domain, which is required for efficient histone binding. In contrast, nucleosome assembly activity of GRWD1 was not affected by deletion of the acidic domain. In HeLa cells, the acidic domain of GRWD1 was necessary to maintain chromatin openness and promote MCM loading at replication origins. Taken together, our results suggest that GRWD1 promotes chromatin fluidity by influencing nucleosome structures, e.g., by transient eviction of H2A-H2B, and thereby promotes efficient MCM loading at replication origins.
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Affiliation(s)
- Masahiro Aizawa
- Department of Cellular Biochemistry, Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashiku, Fukuoka 812-8582, Japan
| | - Nozomi Sugimoto
- Department of Cellular Biochemistry, Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashiku, Fukuoka 812-8582, Japan
| | - Shinya Watanabe
- Department of Cellular Biochemistry, Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashiku, Fukuoka 812-8582, Japan
| | - Kazumasa Yoshida
- Department of Cellular Biochemistry, Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashiku, Fukuoka 812-8582, Japan
| | - Masatoshi Fujita
- Department of Cellular Biochemistry, Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashiku, Fukuoka 812-8582, Japan.
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25
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Melters DP, Nye J, Zhao H, Dalal Y. Chromatin Dynamics in Vivo: A Game of Musical Chairs. Genes (Basel) 2015; 6:751-76. [PMID: 26262644 PMCID: PMC4584328 DOI: 10.3390/genes6030751] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Revised: 07/17/2015] [Accepted: 07/28/2015] [Indexed: 01/30/2023] Open
Abstract
Histones are a major component of chromatin, the nucleoprotein complex fundamental to regulating transcription, facilitating cell division, and maintaining genome integrity in almost all eukaryotes. In addition to canonical, replication-dependent histones, replication-independent histone variants exist in most eukaryotes. In recent years, steady progress has been made in understanding how histone variants assemble, their involvement in development, mitosis, transcription, and genome repair. In this review, we will focus on the localization of the major histone variants H3.3, CENP-A, H2A.Z, and macroH2A, as well as how these variants have evolved, their structural differences, and their functional significance in vivo.
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Affiliation(s)
- Daniël P Melters
- Chromatin Structure and Epigenetics Mechanisms Unit, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 41 Library Drive, Bethesda, MD 20892, USA.
| | - Jonathan Nye
- Chromatin Structure and Epigenetics Mechanisms Unit, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 41 Library Drive, Bethesda, MD 20892, USA.
| | - Haiqing Zhao
- Chromatin Structure and Epigenetics Mechanisms Unit, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 41 Library Drive, Bethesda, MD 20892, USA.
- Biophysics Graduate Program, University of Maryland, College Park, MD 20742, USA.
| | - Yamini Dalal
- Chromatin Structure and Epigenetics Mechanisms Unit, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 41 Library Drive, Bethesda, MD 20892, USA.
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26
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Nishie T, Nagata K. Measles virus C protein facilitates transcription by the control of N protein-viral genomic RNA interaction in early phases of infection. Biochem Biophys Res Commun 2015; 463:1262-6. [PMID: 26093303 DOI: 10.1016/j.bbrc.2015.06.099] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2015] [Accepted: 06/14/2015] [Indexed: 01/09/2023]
Abstract
Measles virus (MV) C protein has been known a multifunctional protein involved in anti-IFN response, viral RNA synthesis, and so on. Recent studies have clarified that double-stranded RNA (dsRNA) is derived from viral genomic RNA (vRNA), and the amount of dsRNA was increased in an MV lacking C protein (MV(C-))-infected cells, suggesting that C protein blocks viral RNA synthesis. However, detailed roles of C protein in viral RNA synthesis remain unknown. Here, we have confirmed through time course experiments using Vero/hSLAM cells that as reported previously, the amount of mRNA is increased in MV(C-)-infected cells at 36 h post infection (hpi). In contrast, we found that the transcription level is lower in MV(C-)-infected cells than wild-type MV-infected cells in early phases of infection. Immunoprecipitation assays were performed to find an interactor(s) of C protein, revealed that C protein interacts with N protein in the absence of vRNA and P protein. RNA immunoprecipitation (RIP) assays showed that the interaction between N protein and vRNA was increased in MV(C-)-infected cells. These results suggest that in early phases of infection C protein facilitates viral transcription to control the formation of nascent nucleocapsid composed of N protein and vRNA.
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Affiliation(s)
- Tomomi Nishie
- Department of Infection Biology, Graduate School of Comprehensive Human Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575, Japan; Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575, Japan
| | - Kyosuke Nagata
- Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575, Japan.
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27
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Chiu YF, Sugden AU, Sugden B. Epstein-Barr viral productive amplification reprograms nuclear architecture, DNA replication, and histone deposition. Cell Host Microbe 2014; 14:607-18. [PMID: 24331459 DOI: 10.1016/j.chom.2013.11.009] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Revised: 10/14/2013] [Accepted: 11/15/2013] [Indexed: 12/16/2022]
Abstract
The spontaneous transition of Epstein-Barr virus (EBV) from latency to productive infection is infrequent, making its analysis in the resulting mixed cell populations difficult. We engineered cells to support this transition efficiently and developed EBV DNA variants that could be visualized and measured as fluorescent signals over multiple cell cycles. This approach revealed that EBV's productive replication began synchronously for viral DNAs within a cell but asynchronously between cells. EBV DNA amplification was delayed until early S phase and occurred in factories characterized by the absence of cellular DNA and histones, by a sequential redistribution of PCNA, and by localization away from the nuclear periphery. The earliest amplified DNAs lacked histones accompanying a decline in four histone chaperones. Thus, EBV transits from being dependent on the cellular replication machinery during latency to commandeering both that machinery and nuclear structure for its own reproductive needs.
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Affiliation(s)
- Ya-Fang Chiu
- McArdle Laboratory for Cancer Research, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Arthur U Sugden
- Department of Neuroscience, Brown University, Providence, RI 02912, USA
| | - Bill Sugden
- McArdle Laboratory for Cancer Research, University of Wisconsin-Madison, Madison, WI 53706, USA.
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28
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Schimmack S, Taylor A, Lawrence B, Alaimo D, Schmitz-Winnenthal H, Büchler MW, Modlin IM, Kidd M. A mechanistic role for the chromatin modulator, NAP1L1, in pancreatic neuroendocrine neoplasm proliferation and metastases. Epigenetics Chromatin 2014; 7:15. [PMID: 25071868 PMCID: PMC4112619 DOI: 10.1186/1756-8935-7-15] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2013] [Accepted: 07/08/2014] [Indexed: 12/15/2022] Open
Abstract
Background The chromatin remodeler NAP1L1, which is upregulated in small intestinal neuroendocrine neoplasms (NENs), has been implicated in cell cycle progression. As p57Kip2 (CDKN1C), a negative regulator of proliferation and a tumor suppressor, is controlled by members of the NAP1 family, we tested the hypothesis that NAP1L1 may have a mechanistic role in regulating pancreatic NEN proliferation through regulation of p57Kip2. Results NAP1L1 silencing (siRNA and shRNA/lipofectamine approach) decreased proliferation through inhibition of mechanistic (mammalian) target of rapamycin pathway proteins and their phosphorylation (p < 0.05) in the pancreatic neuroendocrine neoplasm cell line BON in vitro (p < 0.0001) and resulted in significantly smaller (p < 0.05) and lighter (p < 0.05) tumors in the orthotopic pancreatic NEN mouse model. Methylation of the p57Kip2 promoter was decreased by NAP1L1 silencing (p < 0.05), and expression of p57Kip2 (transcript and protein) was upregulated. For methylation of the p57Kip2 promoter, NAP1L1 bound directly to the promoter (−164 to +21, chromatin immunoprecipitation). In 43 pancreatic NEN samples (38 primaries and 5 metastasis), NAP1L1 was over-expressed in metastasis (p < 0.001), expression which was inversely correlated with p57Kip2 (p < 0.01) on mRNA and protein levels. Menin was not differentially expressed. Conclusion NAP1L1 is over-expressed in pancreatic neuroendocrine neoplasm metastases and epigenetically promotes cell proliferation through regulation of p57Kip2 promoter methylation.
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Affiliation(s)
- Simon Schimmack
- Gastrointestinal Pathobiology Research Group, Yale University School of Medicine, PO Box 208602, New Haven, CT 06510, USA ; Department of General, Visceral and Transplantation Surgery, University Hospital Heidelberg, Im Neuenheimer Feld 110, Heidelberg 69120, Germany
| | - Andrew Taylor
- Gastrointestinal Pathobiology Research Group, Yale University School of Medicine, PO Box 208602, New Haven, CT 06510, USA
| | - Ben Lawrence
- Gastrointestinal Pathobiology Research Group, Yale University School of Medicine, PO Box 208602, New Haven, CT 06510, USA
| | - Daniele Alaimo
- Gastrointestinal Pathobiology Research Group, Yale University School of Medicine, PO Box 208602, New Haven, CT 06510, USA
| | - Hubertus Schmitz-Winnenthal
- Department of General, Visceral and Transplantation Surgery, University Hospital Heidelberg, Im Neuenheimer Feld 110, Heidelberg 69120, Germany
| | - Markus W Büchler
- Department of General, Visceral and Transplantation Surgery, University Hospital Heidelberg, Im Neuenheimer Feld 110, Heidelberg 69120, Germany
| | - Irvin M Modlin
- Gastrointestinal Pathobiology Research Group, Yale University School of Medicine, PO Box 208602, New Haven, CT 06510, USA
| | - Mark Kidd
- Gastrointestinal Pathobiology Research Group, Yale University School of Medicine, PO Box 208602, New Haven, CT 06510, USA
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29
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Abstract
Eukaryotic gene regulation involves a balance between packaging of the genome into nucleosomes and enabling access to regulatory proteins and RNA polymerase. Nucleosomes, consisting of DNA wrapped around a core of histone proteins, are integral components of gene regulation that restrict access to both regulatory sequences and the underlying template. In this review, Weber and Henikoff consider how histone variants and their interacting partners are involved in transcriptional regulation through the creation of unique chromatin states. Eukaryotic gene regulation involves a balance between packaging of the genome into nucleosomes and enabling access to regulatory proteins and RNA polymerase. Nucleosomes are integral components of gene regulation that restrict access to both regulatory sequences and the underlying template. Whereas canonical histones package the newly replicated genome, they can be replaced with histone variants that alter nucleosome structure, stability, dynamics, and, ultimately, DNA accessibility. Here we consider how histone variants and their interacting partners are involved in transcriptional regulation through the creation of unique chromatin states.
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Affiliation(s)
- Christopher M Weber
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, USA
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Arimura Y, Kimura H, Oda T, Sato K, Osakabe A, Tachiwana H, Sato Y, Kinugasa Y, Ikura T, Sugiyama M, Sato M, Kurumizaka H. Structural basis of a nucleosome containing histone H2A.B/H2A.Bbd that transiently associates with reorganized chromatin. Sci Rep 2013; 3:3510. [PMID: 24336483 PMCID: PMC3863819 DOI: 10.1038/srep03510] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2013] [Accepted: 11/29/2013] [Indexed: 01/26/2023] Open
Abstract
Human histone H2A.B (formerly H2A.Bbd), a non-allelic H2A variant, exchanges rapidly as compared to canonical H2A, and preferentially associates with actively transcribed genes. We found that H2A.B transiently accumulated at DNA replication and repair foci in living cells. To explore the biochemical function of H2A.B, we performed nucleosome reconstitution analyses using various lengths of DNA. Two types of H2A.B nucleosomes, octasome and hexasome, were formed with 116, 124, or 130 base pairs (bp) of DNA, and only the octasome was formed with 136 or 146 bp DNA. In contrast, only hexasome formation was observed by canonical H2A with 116 or 124 bp DNA. A small-angle X-ray scattering analysis revealed that the H2A.B octasome is more extended, due to the flexible detachment of the DNA regions at the entry/exit sites from the histone surface. These results suggested that H2A.B rapidly and transiently forms nucleosomes with short DNA segments during chromatin reorganization.
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Affiliation(s)
- Yasuhiro Arimura
- Laboratory of Structural Biology, Graduate School of Advanced Science and Engineering, Waseda University, 2-2 wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Hiroshi Kimura
- Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka, Suita, Osaka 565-0871, Japan
- JST, CREST, 1-3 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Takashi Oda
- Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi, Yokohama 230-0045, Japan
| | - Koichi Sato
- Laboratory of Structural Biology, Graduate School of Advanced Science and Engineering, Waseda University, 2-2 wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Akihisa Osakabe
- Laboratory of Structural Biology, Graduate School of Advanced Science and Engineering, Waseda University, 2-2 wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Hiroaki Tachiwana
- Laboratory of Structural Biology, Graduate School of Advanced Science and Engineering, Waseda University, 2-2 wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Yuko Sato
- Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka, Suita, Osaka 565-0871, Japan
- JST, CREST, 1-3 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Yasuha Kinugasa
- Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Tsuyoshi Ikura
- Department of Mutagenesis, Division of Chromatin Regulatory Network, Radiation Biology Center, Kyoto University, Yoshidakonoe, Sakyo-ku, Kyoto 606-8501, Japan
| | - Masaaki Sugiyama
- Research Reactor Institute, Kyoto University, Kumatori, Osaka, 590-0494, Japan
| | - Mamoru Sato
- Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi, Yokohama 230-0045, Japan
- RIKEN SPring-8 Center, 1-1-1 koto, Sayo, Hyogo 679-5148, Japan
| | - Hitoshi Kurumizaka
- Laboratory of Structural Biology, Graduate School of Advanced Science and Engineering, Waseda University, 2-2 wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
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Attia M, Rachez C, Avner P, Rogner UC. Nucleosome assembly proteins and their interacting proteins in neuronal differentiation. Arch Biochem Biophys 2013; 534:20-6. [DOI: 10.1016/j.abb.2012.09.011] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2012] [Revised: 09/21/2012] [Accepted: 09/22/2012] [Indexed: 12/21/2022]
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32
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Abstract
Chromatin acts as an organizer and indexer of genomic DNA and is a highly dynamic and regulated structure with properties directly related to its constituent parts. Histone variants are abundant components of chromatin that replace canonical histones in a subset of nucleosomes, thereby altering nucleosomal characteristics. The present review focuses on the H2A variant histones, summarizing current knowledge of how H2A variants can introduce chemical and functional heterogeneity into chromatin, the positions that nucleosomes containing H2A variants occupy in eukaryotic genomes, and the regulation of these localization patterns.
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White RH, Keberlein M, Jackson V. A mutational mimic analysis of histone H3 post-translational modifications: specific sites influence the conformational state of H3/H4, causing either positive or negative supercoiling of DNA. Biochemistry 2012; 51:8173-88. [PMID: 23003102 DOI: 10.1021/bi300872t] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Histone H3 has specific sites of post-translational modifications that serve as epigenetic signals to cellular machinery to direct various processes. Mutational mimics of these modifications (glutamine for acetylation, methionine and leucine for methylation, and glutamic acid for phosphorylation) were constructed at the relevant sites of the major histone variant, H3.2, and their effects on the conformational equilibrium of the H3/H4 tetramer at physiological ionic strength were determined when bound to or free of DNA. The deposition vehicle used for this analysis was NAP1, nucleosome assembly protein 1. Acetylation mimics in the N-terminus preferentially stabilized the left-handed conformer (DNA negatively supercoiled), and mutations within the globular region preferred the right-handed conformer (DNA positively supercoiled). The methylation mimics in the N-terminus tended to maintain characteristics similar to those of wild-type H3/H4; i.e., the conformational equilibrium maintains similar levels of both left- and right-handed conformers. Phosphorylation mimics facilitated a mixed effect, i.e., when at serines, the left-handed conformer, and at threonines, a mixture of both conformers. When double mutations were present, the conformational equilibrium was shifted dramatically, either leftward or rightward depending on the specific sites. In contrast, these mutations tended not to affect the direction and extent of supercoiling for variants H3.1 and H3.3. Variant H3.3 promoted only the left-handed conformer, and H3.1 tended to maintain both conformers. Additional experiments indicate the importance of a propagation mechanism for ensuring the formation of a particular superhelical state over an extended region of the DNA. The potential relevance of these results to the maintenance of epigenetic information on a gene is discussed.
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Affiliation(s)
- Rachel H White
- Department of Biochemistry, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
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34
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Bönisch C, Hake SB. Histone H2A variants in nucleosomes and chromatin: more or less stable? Nucleic Acids Res 2012; 40:10719-41. [PMID: 23002134 PMCID: PMC3510494 DOI: 10.1093/nar/gks865] [Citation(s) in RCA: 210] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
In eukaryotes, DNA is organized together with histones and non-histone proteins into a highly complex nucleoprotein structure called chromatin, with the nucleosome as its monomeric subunit. Various interconnected mechanisms regulate DNA accessibility, including replacement of canonical histones with specialized histone variants. Histone variant incorporation can lead to profound chromatin structure alterations thereby influencing a multitude of biological processes ranging from transcriptional regulation to genome stability. Among core histones, the H2A family exhibits highest sequence divergence, resulting in the largest number of variants known. Strikingly, H2A variants differ mostly in their C-terminus, including the docking domain, strategically placed at the DNA entry/exit site and implicated in interactions with the (H3–H4)2-tetramer within the nucleosome and in the L1 loop, the interaction interface of H2A–H2B dimers. Moreover, the acidic patch, important for internucleosomal contacts and higher-order chromatin structure, is altered between different H2A variants. Consequently, H2A variant incorporation has the potential to strongly regulate DNA organization on several levels resulting in meaningful biological output. Here, we review experimental evidence pinpointing towards outstanding roles of these highly variable regions of H2A family members, docking domain, L1 loop and acidic patch, and close by discussing their influence on nucleosome and higher-order chromatin structure and stability.
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Affiliation(s)
- Clemens Bönisch
- Department of Molecular Biology, Center for Integrated Protein Science Munich, Adolf-Butenandt-Institute, Ludwig-Maximilians-University Munich, 80336 Munich, Germany.
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35
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Okuwaki M, Sumi A, Hisaoka M, Saotome-Nakamura A, Akashi S, Nishimura Y, Nagata K. Function of homo- and hetero-oligomers of human nucleoplasmin/nucleophosmin family proteins NPM1, NPM2 and NPM3 during sperm chromatin remodeling. Nucleic Acids Res 2012; 40:4861-78. [PMID: 22362753 PMCID: PMC3367197 DOI: 10.1093/nar/gks162] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Sperm chromatin remodeling after oocyte entry is the essential step that initiates embryogenesis. This reaction involves the removal of sperm-specific basic proteins and chromatin assembly with histones. In mammals, three nucleoplasmin/nucleophosmin (NPM) family proteins-NPM1, NPM2 and NPM3-expressed in oocytes are presumed to cooperatively regulate sperm chromatin remodeling. We characterized the sperm chromatin decondensation and nucleosome assembly activities of three human NPM proteins. NPM1 and NPM2 mediated nucleosome assembly independently of other NPM proteins, whereas the function of NPM3 was largely dependent on formation of a complex with NPM1. Maximal sperm chromatin remodeling activity of NPM2 required the inhibition of its non-specific nucleic acid-binding activity by phosphorylation. Furthermore, the oligomer formation with NPM1 elicited NPM3 nucleosome assembly and sperm chromatin decondensation activity. NPM3 also suppressed the RNA-binding activity of NPM1, which enhanced the nucleoplasm-nucleolus shuttling of NPM1 in somatic cell nuclei. Our results proposed a novel mechanism whereby three NPM proteins cooperatively regulate chromatin disassembly and assembly in the early embryo and in somatic cells.
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Affiliation(s)
- Mitsuru Okuwaki
- Faculty of Medicine and Graduate School of Comprehensive Human Sciences, Initiative for Promotion of Young Scientists' Independent Research, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8577, Japan.
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36
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Samad MA, Komatsu T, Okuwaki M, Nagata K. B23/nucleophosmin is involved in regulation of adenovirus chromatin structure at late infection stages, but not in virus replication and transcription. J Gen Virol 2012; 93:1328-1338. [PMID: 22337638 DOI: 10.1099/vir.0.036665-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
B23/nucleophosmin has been identified in vitro as a stimulatory factor for replication of adenovirus DNA complexed with viral basic core proteins. In the present study, the in vivo function of B23 in the adenovirus life cycle was studied. It was found that both the expression of a decoy mutant derived from adenovirus core protein V that tightly associates with B23 and small interfering RNA-mediated depletion of B23 impeded the production of progeny virions. However, B23 depletion did not significantly affect the replication and transcription of the virus genome. Chromatin immunoprecipitation analyses revealed that B23 depletion significantly increased the association of viral DNA with viral core proteins and cellular histones. These results suggest that B23 is involved in the regulation of association and/or dissociation of core proteins and cellular histones with the virus genome. In addition, these results suggest that proper viral chromatin assembly, regulated in part by B23, is crucial for the maturation of infectious virus particles.
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Affiliation(s)
- Mohammad Abdus Samad
- Department of Applied Nutrition and Food Technology, Faculty of Applied Science and Technology, Islamic University, Kushtia, Bangladesh.,Graduate School of Comprehensive Human Sciences and Faculty of Medicine, University of Tsukuba, 1-1-1 Tennohdai, Tsukuba 305-8575, Japan
| | - Tetsuro Komatsu
- Graduate School of Comprehensive Human Sciences and Faculty of Medicine, University of Tsukuba, 1-1-1 Tennohdai, Tsukuba 305-8575, Japan
| | - Mitsuru Okuwaki
- Initiatives for the Promotion of Young Scientists' Independent Research, University of Tsukuba, 1-1-1 Tennohdai, Tsukuba 305-8577, Japan.,Graduate School of Comprehensive Human Sciences and Faculty of Medicine, University of Tsukuba, 1-1-1 Tennohdai, Tsukuba 305-8575, Japan
| | - Kyosuke Nagata
- Graduate School of Comprehensive Human Sciences and Faculty of Medicine, University of Tsukuba, 1-1-1 Tennohdai, Tsukuba 305-8575, Japan
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Kato K, Okuwaki M, Nagata K. Role of Template Activating Factor-I as a chaperone in linker histone dynamics. J Cell Sci 2012; 124:3254-65. [PMID: 21940793 DOI: 10.1242/jcs.083139] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Linker histone H1 is a fundamental chromosomal protein involved in the maintenance of higher-ordered chromatin organization. The exchange dynamics of histone H1 correlates well with chromatin plasticity. A variety of core histone chaperones involved in core histone dynamics has been identified, but the identity of the linker histone chaperone in the somatic cell nucleus has been a long-standing unanswered question. Here we show that Template Activating Factor-I (TAF-I, also known as protein SET) is involved in histone H1 dynamics as a linker histone chaperone. Among previously identified core histone chaperones and linker histone chaperone candidates, only TAF-I was found to be associated specifically with histone H1 in mammalian somatic cell nuclei. TAF-I showed linker histone chaperone activity in vitro. Fluorescence recovery after photobleaching analyses revealed that TAF-I is involved in the regulation of histone H1 dynamics in the nucleus. Therefore, we propose that TAF-I is a key molecule that regulates linker histone-mediated chromatin assembly and disassembly.
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Affiliation(s)
- Kohsuke Kato
- Department of Infection Biology, Graduate School of Comprehensive Human Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575, Japan
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38
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Fujimoto S, Seebart C, Guastafierro T, Prenni J, Caiafa P, Zlatanova J. Proteome analysis of protein partners to nucleosomes containing canonical H2A or the variant histones H2A.Z or H2A.X. Biol Chem 2012; 393:47-61. [DOI: 10.1515/bc-2011-216] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2011] [Accepted: 11/21/2011] [Indexed: 12/14/2022]
Abstract
Abstract
Although the existence of histone variants has been known for quite some time, only recently are we grasping the breadth and diversity of the cellular processes in which they are involved. Of particular interest are the two variants of histone H2A, H2A.Z and H2A.X because of their roles in regulation of gene expression and in DNA double-strand break repair, respectively. We hypothesize that nucleosomes containing these variants may perform their distinct functions by interacting with different sets of proteins. Here, we present our proteome analysis aimed at identifying protein partners that interact with nucleosomes containing H2A.Z, H2A.X or their canonical H2A counterpart. Our development of a nucleosome-pull down assay and analysis of the recovered nucleosome-interacting proteins by mass spectrometry allowed us to directly compare nuclear partners of these variant-containing nucleosomes to those containing canonical H2A. To our knowledge, our data represent the first systematic analysis of the H2A.Z and H2A.X interactome in the context of nucleosome structure.
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39
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Assembly states of the nucleosome assembly protein 1 (NAP-1) revealed by sedimentation velocity and non-denaturing MS. Biochem J 2011; 436:101-12. [DOI: 10.1042/bj20102063] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Proteins often exist as ensembles of interconverting states in solution which are often difficult to quantify. In the present manuscript we show that the combination of MS under nondenaturing conditions and AUC-SV (analytical ultracentrifugation sedimentation velocity) unambiguously clarifies a distribution of states and hydrodynamic shapes of assembled oligomers for the NAP-1 (nucleosome assembly protein 1). MS established the number of associated units, which was utilized as input for the numerical analysis of AUC-SV profiles. The AUC-SV analysis revealed that less than 1% of NAP-1 monomer exists at the micromolar concentration range and that the basic assembly unit consists of dimers of yeast or human NAP-1. These dimers interact non-covalently to form even-numbered higher-assembly states, such as tetramers, hexamers, octamers and decamers. MS and AUC-SV consistently showed that the formation of the higher oligomers was suppressed with increasing ionic strength, implicating electrostatic interactions in the formation of higher oligomers. The hydrodynamic shapes of the NAP-1 tetramer estimated from AUC-SV agreed with the previously proposed assembly models built using the known three-dimensional structure of yeast NAP-1. Those of the hexamer and octamer could be represented by new models shown in the present study. Additionally, MS was used to measure the stoichiometry of the interaction between the human NAP-1 dimer and the histone H2A–H2B dimer or H3–H4 tetramer. The present study illustrates a rigorous procedure for the analysis of protein assembly and protein–protein interactions in solution.
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Seebart C, Prenni J, Tomschik M, Zlatanova J. New nuclear partners for nucleosome assembly protein 1: unexpected associations. Biochem Cell Biol 2011; 88:927-36. [PMID: 21102655 DOI: 10.1139/o10-115] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Histone chaperones are important players in chromatin dynamics. They are instrumental in nucleosome assembly and disassembly and in histone variant exchange reactions that occur during DNA transactions. The molecular mechanisms of their action are not well understood and may involve interactions with various protein partners in the context of the nucleus. In an attempt to further elucidate nuclear roles of histone chaperones, we performed a proteomic search for nuclear partners of a particular histone chaperone, nucleosome assembly protein 1 (Nap1). Proteins recognized as Nap1 partners by immuno-affinity capture and Far Western blots were identified by mass spectrometry. The identified partners are known to participate in a number of nuclear processes, including DNA replication, recombination, and repair as well as RNA transcription and splicing. Finding nuclear actin among the Nap1 partners may be of particular significance, in view of actin's role in transcription, transcription regulation, and RNA splicing. We are proposing a model of how actin-Nap1 interaction may be involved in transcription elongation through chromatin. In addition, awareness of the interactions between Nap1 and Hsp70, another identified partner, may help to understand nucleosome dynamics around sites of single-strand DNA break repair. These studies represent a starting point for further investigation of Nap1 associations in human cells.
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Affiliation(s)
- Corrine Seebart
- Department of Molecular Biology, University of Wyoming, Laramie, WY 82071, USA
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41
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Regulation of nucleolar chromatin by B23/nucleophosmin jointly depends upon its RNA binding activity and transcription factor UBF. Mol Cell Biol 2010; 30:4952-64. [PMID: 20713446 DOI: 10.1128/mcb.00299-10] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Histone chaperones regulate the density of incorporated histone proteins around DNA transcription sites and therefore constitute an important site-specific regulatory mechanism for the control of gene expression. At present, the targeting mechanism conferring this site specificity is unknown. We previously reported that the histone chaperone B23/nucleophosmin associates with rRNA chromatin (r-chromatin) to stimulate rRNA transcription. Here, we report on the mechanism for site-specific targeting of B23 to the r-chromatin. We observed that, during mitosis, B23 was released from chromatin upon inactivation of its RNA binding activity by cdc2 kinase-mediated phosphorylation. The phosphorylation status of B23 was also shown to strongly affect its chromatin binding activity. We further found that r-chromatin binding of B23 was a necessary condition for B23 histone chaperone activity in vivo. In addition, we found that depletion of upstream binding factor (UBF; an rRNA transcription factor) decreased the chromatin binding affinity of B23, which in turn led to an increase in histone density at the r-chromatin. These two major strands of evidence suggest a novel cell cycle-dependent mechanism for the site-specific regulation of histone density via joint RNA- and transcription factor-mediated recruitment of histone chaperones to specific chromosome loci.
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42
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Hansen JC, Nyborg JK, Luger K, Stargell LA. Histone chaperones, histone acetylation, and the fluidity of the chromogenome. J Cell Physiol 2010; 224:289-99. [PMID: 20432449 DOI: 10.1002/jcp.22150] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The "chromogenome" is defined as the structural and functional status of the genome at any given moment within a eukaryotic cell. This article focuses on recently uncovered relationships between histone chaperones, post-translational acetylation of histones, and modulation of the chromogenome. We emphasize those chaperones that function in a replication-independent manner, and for which three-dimensional structural information has been obtained. The emerging links between histone acetylation and chaperone function in both yeast and higher metazoans are discussed, including the importance of nucleosome-free regions. We close by posing many questions pertaining to how the coupled action of histone chaperones and acetylation influences chromogenome structure and function.
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Affiliation(s)
- Jeffrey C Hansen
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, Colorado 80523, USA.
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43
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Abstract
Histones wrap DNA to form nucleosome particles that compact eukaryotic genomes. Variant histones have evolved crucial roles in chromosome segregation, transcriptional regulation, DNA repair, sperm packaging and other processes. 'Universal' histone variants emerged early in eukaryotic evolution and were later displaced for bulk packaging roles by the canonical histones (H2A, H2B, H3 and H4), the synthesis of which is coupled to DNA replication. Further specializations of histone variants have evolved in some lineages to perform additional tasks. Differences among histone variants in their stability, DNA wrapping, specialized domains that regulate access to DNA, and post-translational modifications, underlie the diverse functions that histones have acquired in evolution.
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Osakabe A, Tachiwana H, Matsunaga T, Shiga T, Nozawa RS, Obuse C, Kurumizaka H. Nucleosome formation activity of human somatic nuclear autoantigenic sperm protein (sNASP). J Biol Chem 2010; 285:11913-21. [PMID: 20167597 DOI: 10.1074/jbc.m109.083238] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
NASP (nuclear autoantigenic sperm protein) is a member of the N1/N2 family, which is widely conserved among eukaryotes. Human NASP reportedly prefers to bind to histones H3.H4 and the linker histone H1, as compared with H2A.H2B, and is anticipated to function as an H3.H4 chaperone for nucleosome assembly. However, the direct nucleosome assembly activity of human NASP has not been reported so far. In humans, two spliced isoforms, somatic and testicular NASPs (sNASP and tNASP, respectively) were identified. In the present study we purified human sNASP and found that sNASP efficiently promoted the assembly of nucleosomes containing the conventional H3.1, H3.2, H3.3, or centromere-specific CENP-A. On the other hand, sNASP inefficiently promoted nucleosome assembly with H3T, a testis-specific H3 variant. Mutational analyses revealed that the Met-71 residue of H3T is responsible for this inefficient nucleosome formation by sNASP. Tetrasomes, composed of the H3.H4 tetramer and DNA without H2A.H2B, were efficiently formed by the sNASP-mediated nucleosome-assembly reaction. A deletion analysis of sNASP revealed that the central region, amino acid residues 26-325, of sNASP is responsible for nucleosome assembly in vitro. These experiments are the first demonstration that human NASP directly promotes nucleosome assembly and provide compelling evidence that sNASP is a bona fide histone chaperone for H3.H4.
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Affiliation(s)
- Akihisa Osakabe
- Laboratory of Structural Biology, Graduate School of Advanced Science and Engineering, Waseda University, Shinjuku-ku, Tokyo 162-8480, Japan
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New insights into two distinct nucleosome distributions: comparison of cross-platform positioning datasets in the yeast genome. BMC Genomics 2010; 11:33. [PMID: 20078849 PMCID: PMC2824721 DOI: 10.1186/1471-2164-11-33] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2009] [Accepted: 01/15/2010] [Indexed: 11/30/2022] Open
Abstract
Background Recently, a number of high-resolution genome-wide maps of nucleosome locations in S. cerevisiae have been derived experimentally. However, nucleosome positions are determined in vivo by the combined effects of numerous factors. Consequently, nucleosomes are not simple static units, which may explain the discrepancies in reported nucleosome positions as measured by different experiments. In order to more accurately depict the genome-wide nucleosome distribution, we integrated multiple nucleosomal positioning datasets using a multi-angle analysis strategy. Results To evaluate the contribution of chromatin structure to transcription, we used the vast amount of available nucleosome analyzed data. Analysis of this data allowed for the comprehensive identification of the connections between promoter nucleosome positioning patterns and various transcription-dependent properties. Further, we characterised the function of nucleosome destabilisation in the context of transcription regulation. Our results indicate that genes with similar nucleosome occupancy patterns share general transcription attributes. We identified the local regulatory correlation (LRC) regions for two distinct types of nucleosomes and we assessed their regulatory properties. We also estimated the nucleosome reproducibility and measurement accuracy for high-confidence transcripts. We found that by maintaining a distance of ~13 bp between the upstream border of the +1 nucleosome and the transcription start sites (TSSs), the stable +1 nucleosome may form a barrier against the accessibility of the TSS and shape an optimum chromatin conformation for gene regulation. An in-depth analysis of nucleosome positioning in normally growing and heat shock cells suggested that the extent and patterns of nucleosome sliding are associated with gene activation. Conclusions Our results, which combine different types of data, suggest that cross-platform information, including discrepancy and consistency, reflects the mechanisms of nucleosome packaging in vivo more faithfully than individual studies. Furthermore, nucleosomes can be divided into two classes according to their stable and dynamic characteristics. We found that two different nucleosome-positioning characteristics may significantly impact transcription programs. Besides, some positioned-nucleosomes are involved in the transition from stable state to dynamic state in response to abrupt environmental changes.
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Okuwaki M, Kato K, Nagata K. Functional characterization of human nucleosome assembly protein 1-like proteins as histone chaperones. Genes Cells 2010; 15:13-27. [DOI: 10.1111/j.1365-2443.2009.01361.x] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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Ishibashi T, Li A, Eirín-López JM, Zhao M, Missiaen K, Abbott DW, Meistrich M, Hendzel MJ, Ausió J. H2A.Bbd: an X-chromosome-encoded histone involved in mammalian spermiogenesis. Nucleic Acids Res 2009; 38:1780-9. [PMID: 20008104 PMCID: PMC2847216 DOI: 10.1093/nar/gkp1129] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Despite the identification of H2A.Bbd as a new vertebrate-specific replacement histone variant several years ago, and despite the many in vitro structural characterizations using reconstituted chromatin complexes consisting of this variant, the existence of H2A.Bbd in the cell and its location has remained elusive. Here, we report that the native form of this variant is present in highly advanced spermiogenic fractions of mammalian testis at the time when histones are highly acetylated and being replaced by protamines. It is also present in the nucleosomal chromatin fraction of mature human sperm. The ectopically expressed non-tagged version of the protein is associated with micrococcal nuclease-refractory insoluble fractions of chromatin and in mouse (20T1/2) cell line, H2A.Bbd is enriched at the periphery of chromocenters. The exceedingly rapid evolution of this unique X-chromosome-linked histone variant is shared with other reproductive proteins including those associated with chromatin in the mature sperm (protamines) of many vertebrates. This common rate of evolution provides further support for the functional and structural involvement of this protein in male gametogenesis in mammals.
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Affiliation(s)
- Toyotaka Ishibashi
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC V8W 3P6, Canada
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Subcellular localization of the interaction between the human immunodeficiency virus transactivator Tat and the nucleosome assembly protein 1. Amino Acids 2009; 38:1583-93. [DOI: 10.1007/s00726-009-0378-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2009] [Accepted: 10/14/2009] [Indexed: 10/20/2022]
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Nucleosome assembly proteins bind to Epstein-Barr virus nuclear antigen 1 and affect its functions in DNA replication and transcriptional activation. J Virol 2009; 83:11704-14. [PMID: 19726498 DOI: 10.1128/jvi.00931-09] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The EBNA1 protein of Epstein-Barr virus (EBV) plays several important roles in EBV latent infection, including activating DNA replication from the latent origin of replication (oriP) and activating the transcription of other latency genes within the EBV chromatin. These functions require EBNA1 binding to the DS and FR elements within oriP, respectively, although how these interactions activate these processes is not clear. We previously identified interactions of EBNA1 with the related nucleosome assembly proteins NAP1 and TAF-I, known to affect the replication and transcription of other chromatinized templates. We have further investigated these interactions, showing that EBNA1 binds directly to NAP1 and to the beta isoform of TAF-I (also called SET) and that these interactions greatly increase the solubility of EBNA1 in vitro. These interactions were confirmed in EBV-infected cells, and chromatin immunoprecipitation with these cells showed that NAP1 and TAF-I both localized with EBNA1 to the FR element, while only TAF-I was detected with EBNA1 at the DS element. In keeping with these observations, alteration of the NAP1 or TAF-Ibeta level by RNA interference and overexpression inhibited transcriptional activation by EBNA1 in FR reporter assays. In addition, EBNA1-mediated DNA replication was stimulated when TAF-I (but not NAP1) was downregulated and was inhibited by TAF-Ibeta overexpression. The results indicate that the interaction of EBNA1 with NAP1 and TAF-I is important for transcriptional activation and that EBNA1 recruits TAF-I to the DS element, where it negatively regulates DNA replication.
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Karetsou Z, Emmanouilidou A, Sanidas I, Liokatis S, Nikolakaki E, Politou AS, Papamarcaki T. Identification of distinct SET/TAF-Ibeta domains required for core histone binding and quantitative characterisation of the interaction. BMC BIOCHEMISTRY 2009; 10:10. [PMID: 19358706 PMCID: PMC2676315 DOI: 10.1186/1471-2091-10-10] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/24/2008] [Accepted: 04/09/2009] [Indexed: 11/10/2022]
Abstract
BACKGROUND The assembly of nucleosomes to higher-order chromatin structures is finely tuned by the relative affinities of histones for chaperones and nucleosomal binding sites. The myeloid leukaemia protein SET/TAF-Ibeta belongs to the NAP1 family of histone chaperones and participates in several chromatin-based mechanisms, such as chromatin assembly, nucleosome reorganisation and transcriptional activation. To better understand the histone chaperone function of SET/TAF-Ibeta, we designed several SET/TAF-Ibeta truncations, examined their structural integrity by circular Dichroism and assessed qualitatively and quantitatively the histone binding properties of wild-type protein and mutant forms using GST-pull down experiments and fluorescence spectroscopy-based binding assays. RESULTS Wild type SET/TAF-Ibeta binds to histones H2B and H3 with Kd values of 2.87 and 0.15 microM, respectively. The preferential binding of SET/TAF-Ibeta to histone H3 is mediated by its central region and the globular part of H3. On the contrary, the acidic C-terminal tail and the amino-terminal dimerisation domain of SET/TAF-Ibeta, as well as the H3 amino-terminal tail, are dispensable for this interaction. CONCLUSION This type of analysis allowed us to assess the relative affinities of SET/TAF-Ibeta for different histones and identify the domains of the protein required for effective histone recognition. Our findings are consistent with recent structural studies of SET/TAF-Ibeta and can be valuable to understand the role of SET/TAF-Ibeta in chromatin function.
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Affiliation(s)
- Zoe Karetsou
- Laboratory of Biological Chemistry, Medical School, University of Ioannina, 451 10 Ioannina, Greece.
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