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Meiotic CENP-C is a shepherd: bridging the space between the centromere and the kinetochore in time and space. Essays Biochem 2020; 64:251-261. [PMID: 32794572 DOI: 10.1042/ebc20190080] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 07/15/2020] [Accepted: 07/20/2020] [Indexed: 01/10/2023]
Abstract
While many of the proteins involved in the mitotic centromere and kinetochore are conserved in meiosis, they often gain a novel function due to the unique needs of homolog segregation during meiosis I (MI). CENP-C is a critical component of the centromere for kinetochore assembly in mitosis. Recent work, however, has highlighted the unique features of meiotic CENP-C. Centromere establishment and stability require CENP-C loading at the centromere for CENP-A function. Pre-meiotic loading of proteins necessary for homolog recombination as well as cohesion also rely on CENP-C, as do the main scaffolding components of the kinetochore. Much of this work relies on new technologies that enable in vivo analysis of meiosis like never before. Here, we strive to highlight the unique role of this highly conserved centromere protein that loads on to centromeres prior to M-phase onset, but continues to perform critical functions through chromosome segregation. CENP-C is not merely a structural link between the centromere and the kinetochore, but also a functional one joining the processes of early prophase homolog synapsis to late metaphase kinetochore assembly and signaling.
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2
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Jing R, Xi J, Leng Y, Chen W, Wang G, Jia W, Kang J, Zhu S. Motifs in the amino-terminus of CENP-A are required for its accumulation within the nucleus and at the centromere. Oncotarget 2017; 8:40654-40667. [PMID: 28489565 PMCID: PMC5522188 DOI: 10.18632/oncotarget.17204] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Accepted: 04/07/2017] [Indexed: 11/25/2022] Open
Abstract
Centromere protein A (CENP-A) is a variant of core histone H3 that marks the centromere's location on the chromosome. The mechanisms that target the protein to the nucleus and the centromere have not been defined. In this study, we found that deletion of the first 53 but not the first 29 residues of CENP-A from the amino-terminus, resulted in its cytoplasmic localization. Two motifs, R42R43R44 and K49R52K53K56, which are reported to be required for DNA contact in the centromere nucleosome, were found to be critical for CENP-A nuclear accumulation. These two motifs potentially mediated its interaction with Importin-β but were not involved in CENP-A centromeric localization. A third novel motif, L60L61I62R63K64, was found to be essential for the centromeric accumulation of CENP-A. The nonpolar hydrophobic residues L60L61I62, but not the basic residues R63K64, were found to be the most important residues. A protein interaction assay suggested that this motif is not involved in the interaction of CENP-A with its deposition factors but potentially mediates its interaction with core histone H4 and CENP-B. Our study uncovered the role of the amino-terminus of CENP-A in localization.
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Affiliation(s)
- Ruiqi Jing
- Clinical and Translational Research Center of Shanghai First Maternity and Infant Health Hospital, Shanghai Key Laboratory of Signaling and Disease Research, Collaborative Innovation Center for Brain Science, School of Life Science and Technology, Tongji University, Shanghai, 200092, China
| | - Jiajie Xi
- Clinical and Translational Research Center of Shanghai First Maternity and Infant Health Hospital, Shanghai Key Laboratory of Signaling and Disease Research, Collaborative Innovation Center for Brain Science, School of Life Science and Technology, Tongji University, Shanghai, 200092, China
| | - Ye Leng
- Clinical and Translational Research Center of Shanghai First Maternity and Infant Health Hospital, Shanghai Key Laboratory of Signaling and Disease Research, Collaborative Innovation Center for Brain Science, School of Life Science and Technology, Tongji University, Shanghai, 200092, China
| | - Wen Chen
- Clinical and Translational Research Center of Shanghai First Maternity and Infant Health Hospital, Shanghai Key Laboratory of Signaling and Disease Research, Collaborative Innovation Center for Brain Science, School of Life Science and Technology, Tongji University, Shanghai, 200092, China
| | - Guiying Wang
- Clinical and Translational Research Center of Shanghai First Maternity and Infant Health Hospital, Shanghai Key Laboratory of Signaling and Disease Research, Collaborative Innovation Center for Brain Science, School of Life Science and Technology, Tongji University, Shanghai, 200092, China
| | - Wenwen Jia
- Clinical and Translational Research Center of Shanghai First Maternity and Infant Health Hospital, Shanghai Key Laboratory of Signaling and Disease Research, Collaborative Innovation Center for Brain Science, School of Life Science and Technology, Tongji University, Shanghai, 200092, China
| | - Jiuhong Kang
- Clinical and Translational Research Center of Shanghai First Maternity and Infant Health Hospital, Shanghai Key Laboratory of Signaling and Disease Research, Collaborative Innovation Center for Brain Science, School of Life Science and Technology, Tongji University, Shanghai, 200092, China
| | - Songcheng Zhu
- Clinical and Translational Research Center of Shanghai First Maternity and Infant Health Hospital, Shanghai Key Laboratory of Signaling and Disease Research, Collaborative Innovation Center for Brain Science, School of Life Science and Technology, Tongji University, Shanghai, 200092, China
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Hemmerich P, Weidtkamp-Peters S, Hoischen C, Schmiedeberg L, Erliandri I, Diekmann S. Dynamics of inner kinetochore assembly and maintenance in living cells. ACTA ACUST UNITED AC 2008; 180:1101-14. [PMID: 18347072 PMCID: PMC2290840 DOI: 10.1083/jcb.200710052] [Citation(s) in RCA: 147] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
To investigate the dynamics of centromere organization, we have assessed the exchange rates of inner centromere proteins (CENPs) by quantitative microscopy throughout the cell cycle in human cells. CENP-A and CENP-I are stable centromere components that are incorporated into centromeres via a “loading-only” mechanism in G1 and S phase, respectively. A subfraction of CENP-H also stays stably bound to centromeres. In contrast, CENP-B, CENP-C, and some CENP-H and hMis12 exhibit distinct and cell cycle–specific centromere binding stabilities, with residence times ranging from seconds to hours. CENP-C and CENP-H are immobilized at centromeres specifically during replication. In mitosis, all inner CENPs become completely immobilized. CENPs are highly mobile throughout bulk chromatin, which is consistent with a binding-diffusion behavior as the mechanism to scan for vacant high-affinity binding sites at centromeres. Our data reveal a wide range of cell cycle–specific assembly plasticity of the centromere that provides both stability through sustained binding of some components and flexibility through dynamic exchange of other components.
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Affiliation(s)
- Peter Hemmerich
- Leibniz Institute for Age Research, Fritz Lipmann Institute, 07745 Jena, Germany. phemmer@fl i-leibniz.de
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Thaminy S, Newcomb B, Kim J, Gatbonton T, Foss E, Simon J, Bedalov A. Hst3 Is Regulated by Mec1-dependent Proteolysis and Controls the S Phase Checkpoint and Sister Chromatid Cohesion by Deacetylating Histone H3 at Lysine 56. J Biol Chem 2007; 282:37805-14. [DOI: 10.1074/jbc.m706384200] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
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5
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Han J, Zhou H, Li Z, Xu RM, Zhang Z. Acetylation of lysine 56 of histone H3 catalyzed by RTT109 and regulated by ASF1 is required for replisome integrity. J Biol Chem 2007; 282:28587-28596. [PMID: 17690098 DOI: 10.1074/jbc.m702496200] [Citation(s) in RCA: 141] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
In budding yeast, acetylation of histone H3 lysine 56 (H3-K56) is catalyzed by the Rtt109-Vps75 histone acetyltransferase (HAT) complex, with Rtt109 being the catalytic subunit, and histone chaperone Asf1 is required for this modification. Cells lacking Rtt109 are susceptible to perturbations in DNA replication. However, how Asf1 regulates acetylation of H3-K56 and how loss of H3-K56 acetylation affects DNA replication are unclear. We show that at low concentrations the Rtt109-Vps75 HAT complex acetylates H3-K56 in vitro when H3/H4 is complexed with Asf1, but not H3/H4 tetramers, recapitulating the in vivo requirement of Asf1 for H3-K56 acetylation using recombinant proteins. Moreover, the Rtt109-Vps75 complex interacts with Asf1-H3/H4 but not Asf1. In vivo, the Rtt109-Asf1 interaction is also dependent on the ability of Asf1 to bind H3/H4. Furthermore, the Rtt109 homolog in Schizosaccharomyces pombe (SpRtt109) also displayed an Asf1-dependent H3-K56 HAT activity in vitro. These results indicate that Asf1 regulates H3-K56 acetylation by presenting histones H3 and H4 to Rtt109-Vps575 for acetylation, and this mechanism is likely to be conserved. Finally, we have shown that cells lacking Rtt109 or expressing H3-K56 mutants exhibited significant reduction in the association of three proteins with stalled DNA replication forks and hyper-recombination of replication forks stalled at replication fork barriers of the ribosomal DNA locus compared with wild-type cells. Taken together, these studies provide novel insight into the role of Asf1 in the regulation of H3-K56 acetylation and the function of this modification in DNA replication.
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Affiliation(s)
- Junhong Han
- Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine, Rochester, Minnesota 55905
| | - Hui Zhou
- Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine, Rochester, Minnesota 55905
| | - Zhizhong Li
- Structural Biology Program, Helen L. and Martin S. Kimmel Center for Biology and Medicine, Skirball Institute of Biomedicine and Department of Pharmacology, New York University School of Medicine, New York, New York 10016
| | - Rui-Ming Xu
- Structural Biology Program, Helen L. and Martin S. Kimmel Center for Biology and Medicine, Skirball Institute of Biomedicine and Department of Pharmacology, New York University School of Medicine, New York, New York 10016
| | - Zhiguo Zhang
- Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine, Rochester, Minnesota 55905.
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Endo M, Ishikawa Y, Osakabe K, Nakayama S, Kaya H, Araki T, Shibahara KI, Abe K, Ichikawa H, Valentine L, Hohn B, Toki S. Increased frequency of homologous recombination and T-DNA integration in Arabidopsis CAF-1 mutants. EMBO J 2006; 25:5579-90. [PMID: 17110925 PMCID: PMC1679757 DOI: 10.1038/sj.emboj.7601434] [Citation(s) in RCA: 139] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2006] [Accepted: 10/11/2006] [Indexed: 11/08/2022] Open
Abstract
Chromatin assembly factor 1 (CAF-1) is involved in nucleo some assembly following DNA replication and nucleotide excision repair. In Arabidopsis thaliana, the three CAF-1 subunits are encoded by FAS1, FAS2 and, most likely, MSI1, respectively. In this study, we asked whether genomic stability is altered in fas1 and fas2 mutants that are lacking CAF-1 activity. Depletion of either subunit increased the frequency of somatic homologous recombination (HR) in planta approximately 40-fold. The frequency of transferred DNA (T-DNA) integration was also elevated. A delay in loading histones onto newly replicated or repaired DNA might make these DNA stretches more accessible, both to repair enzymes and to foreign DNA. Furthermore, fas mutants exhibited increased levels of DNA double-strand breaks, a G2-phase retardation that accelerates endoreduplication, and elevated levels of mRNAs coding for proteins involved in HR-all factors that could also contribute to upregulation of HR frequency in fas mutants.
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Affiliation(s)
- Masaki Endo
- Division of Plant Sciences, National Institute of Agrobiological Sciences, Kannondai, Tsukuba, Ibaraki, Japan
- Graduate School of Life Environmental Sciences, University of Tsukuba, Tennodai, Tsukuba, Ibaraki, Japan
| | - Yuichi Ishikawa
- Division of Plant Sciences, National Institute of Agrobiological Sciences, Kannondai, Tsukuba, Ibaraki, Japan
- Graduate School of Life Sciences, Tohoku University, Aoba-ku, Sendai, Miyagi, Japan
| | - Keishi Osakabe
- Division of Plant Sciences, National Institute of Agrobiological Sciences, Kannondai, Tsukuba, Ibaraki, Japan
| | - Shigeki Nakayama
- Division of Plant Sciences, National Institute of Agrobiological Sciences, Kannondai, Tsukuba, Ibaraki, Japan
| | - Hidetaka Kaya
- Department of Botany, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto, Japan
| | - Takashi Araki
- Department of Botany, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto, Japan
| | - Kei-ichi Shibahara
- Department of Integrated Genetics, National Institute of Genetics, Mishima, Shizuoka, Japan
| | - Kiyomi Abe
- Division of Plant Sciences, National Institute of Agrobiological Sciences, Kannondai, Tsukuba, Ibaraki, Japan
| | - Hiroaki Ichikawa
- Division of Plant Sciences, National Institute of Agrobiological Sciences, Kannondai, Tsukuba, Ibaraki, Japan
| | - Lisa Valentine
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Barbara Hohn
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Seiichi Toki
- Division of Plant Sciences, National Institute of Agrobiological Sciences, Kannondai, Tsukuba, Ibaraki, Japan
- Division of Plant Sciences, National Institute of Agrobiological Sciences, 2-1-2 Kannondai, Tsukuba, Ibaraki 305-8602, Japan. Tel.: +81 29 838 8450; Fax: +81 29 838 8450; E-mail:
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7
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Takami Y, Ono T, Fukagawa T, Shibahara KI, Nakayama T. Essential role of chromatin assembly factor-1-mediated rapid nucleosome assembly for DNA replication and cell division in vertebrate cells. Mol Biol Cell 2006; 18:129-41. [PMID: 17065558 PMCID: PMC1751324 DOI: 10.1091/mbc.e06-05-0426] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Chromatin assembly factor-1 (CAF-1), a complex consisting of p150, p60, and p48 subunits, is highly conserved from yeast to humans and facilitates nucleosome assembly of newly replicated DNA in vitro. To investigate roles of CAF-1 in vertebrates, we generated two conditional DT40 mutants, respectively, devoid of CAF-1p150 and p60. Depletion of each of these CAF-1 subunits led to delayed S-phase progression concomitant with slow DNA synthesis, followed by accumulation in late S/G2 phase and aberrant mitosis associated with extra centrosomes, and then the final consequence was cell death. We demonstrated that CAF-1 is necessary for rapid nucleosome formation during DNA replication in vivo as well as in vitro. Loss of CAF-1 was not associated with the apparent induction of phosphorylations of S-checkpoint kinases Chk1 and Chk2. To elucidate the precise role of domain(s) in CAF-1p150, functional dissection analyses including rescue assays were preformed. Results showed that the binding abilities of CAF-1p150 with CAF-1p60 and DNA polymerase sliding clamp proliferating cell nuclear antigen (PCNA) but not with heterochromatin protein HP1-gamma are required for cell viability. These observations highlighted the essential role of CAF-1-dependent nucleosome assembly in DNA replication and cell proliferation through its interaction with PCNA.
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Affiliation(s)
- Yasunari Takami
- *Section of Biochemistry and Molecular Biology, Department of Medical Sciences, Miyazaki Medical College, University of Miyazaki, Miyazaki 889-1692, Japan
| | | | - Tatsuo Fukagawa
- Molecular Genetics, National Institute of Genetics, Shizuoka 411-8540, Japan
| | | | - Tatsuo Nakayama
- *Section of Biochemistry and Molecular Biology, Department of Medical Sciences, Miyazaki Medical College, University of Miyazaki, Miyazaki 889-1692, Japan
- Department of Life Science, Frontier Science Research Center, University of Miyazaki, Miyazaki 889-1692, Japan; and
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8
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Budd ME, Tong AHY, Polaczek P, Peng X, Boone C, Campbell JL. A network of multi-tasking proteins at the DNA replication fork preserves genome stability. PLoS Genet 2005; 1:e61. [PMID: 16327883 PMCID: PMC1298934 DOI: 10.1371/journal.pgen.0010061] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2005] [Accepted: 10/12/2005] [Indexed: 11/18/2022] Open
Abstract
To elucidate the network that maintains high fidelity genome replication, we have introduced two conditional mutant alleles of DNA2, an essential DNA replication gene, into each of the approximately 4,700 viable yeast deletion mutants and determined the fitness of the double mutants. Fifty-six DNA2-interacting genes were identified. Clustering analysis of genomic synthetic lethality profiles of each of 43 of the DNA2-interacting genes defines a network (consisting of 322 genes and 876 interactions) whose topology provides clues as to how replication proteins coordinate regulation and repair to protect genome integrity. The results also shed new light on the functions of the query gene DNA2, which, despite many years of study, remain controversial, especially its proposed role in Okazaki fragment processing and the nature of its in vivo substrates. Because of the multifunctional nature of virtually all proteins at the replication fork, the meaning of any single genetic interaction is inherently ambiguous. The multiplexing nature of the current studies, however, combined with follow-up supporting experiments, reveals most if not all of the unique pathways requiring Dna2p. These include not only Okazaki fragment processing and DNA repair but also chromatin dynamics.
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Affiliation(s)
- Martin E Budd
- Braun Laboratories, California Institute of Technology, Pasadena, California, United States of America
| | - Amy Hin Yan Tong
- Banting and Best Department of Medical Research, University of Toronto, Toronto, Ontario, Canada
- Department of Medical Genetics and Microbiology, University of Toronto, Toronto, Ontario, Canada
| | - Piotr Polaczek
- Braun Laboratories, California Institute of Technology, Pasadena, California, United States of America
| | - Xiao Peng
- Braun Laboratories, California Institute of Technology, Pasadena, California, United States of America
| | - Charles Boone
- Banting and Best Department of Medical Research, University of Toronto, Toronto, Ontario, Canada
- Department of Medical Genetics and Microbiology, University of Toronto, Toronto, Ontario, Canada
| | - Judith L Campbell
- Braun Laboratories, California Institute of Technology, Pasadena, California, United States of America
- * To whom correspondence should be addressed. E-mail:
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9
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Zeitlin SG, Patel S, Kavli B, Slupphaug G. Xenopus CENP-A assembly into chromatin requires base excision repair proteins. DNA Repair (Amst) 2005; 4:760-72. [PMID: 15964249 DOI: 10.1016/j.dnarep.2005.02.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2005] [Revised: 02/25/2005] [Accepted: 02/25/2005] [Indexed: 01/11/2023]
Abstract
CENP-A is an essential histone H3 variant found in all eukaryotes examined to date. To begin to determine how CENP-A is assembled into chromatin, we developed a binding assay using sperm chromatin in cell-free extract derived from Xenopus eggs. Our data suggest that the catalytic activities of an unidentified deoxycytidine deaminase and UNG2, a uracil DNA glycosylase, are involved in CENP-A assembly. In support of this model, inhibiting deoxycytidine deaminase with zebularine, or uracil DNA glycosylase with Ugi, uracil or UTP results in a lack of detectable CENP-A on sperm DNA. Conversely, inducing DNA damage increases the level of CENP-A detected on sperm chromatin. Our data suggest that base excision repair may be involved in assembly of this histone H3 variant.
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Affiliation(s)
- Samantha G Zeitlin
- Department of Biological Sciences, University of California San Diego, Mail Code 0322, La Jolla, CA 92093, USA.
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10
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Wagner G, Bancaud A, Quivy JP, Clapier C, Almouzni G, Viovy JL. Compaction kinetics on single DNAs: purified nucleosome reconstitution systems versus crude extract. Biophys J 2005; 89:3647-59. [PMID: 16100259 PMCID: PMC1366857 DOI: 10.1529/biophysj.105.062786] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Kinetics of compaction on single DNA molecules are studied by fluorescence videomicroscopy in the presence of 1), Xenopus egg extracts and 2), purified nucleosome reconstitution systems using a combination of histones with either the histone chaperone Nucleosome Assembly Protein (NAP-1) or negatively charged macromolecules such as polyglutamic acid and RNA. The comparison shows that the compaction rates can differ by a factor of up to 1000 for the same amount of histones, depending on the system used and on the presence of histone tails, which can be subjected to post-translational modifications. Reactions with purified reconstitution systems follow a slow and sequential mechanism, compatible with the deposition of one (H3-H4)(2) tetramer followed by two (H2A-H2B) dimers. Addition of the histone chaperone NAP-1 increases both the rate of the reaction and the packing ratio of the final product. These stimulatory effects cannot be obtained with polyglutamic acid or RNA, suggesting that yNAP-1 impact on the reaction cannot simply be explained in terms of charge screening. Faster compaction kinetics and higher packing ratios are reproducibly reached with extracts, indicating a role of additional components present in this system. Data are discussed and models proposed to account for the kinetics obtained in our single-molecule assay.
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Affiliation(s)
- Gaudeline Wagner
- Laboratoire PhysicoChimie Curie, Institut Curie, CNRS UMR 168, 75248 Paris, France
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11
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Zhou J, Chau CM, Deng Z, Shiekhattar R, Spindler MP, Schepers A, Lieberman PM. Cell cycle regulation of chromatin at an origin of DNA replication. EMBO J 2005; 24:1406-17. [PMID: 15775975 PMCID: PMC1142536 DOI: 10.1038/sj.emboj.7600609] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2004] [Accepted: 02/08/2005] [Indexed: 01/01/2023] Open
Abstract
Selection and licensing of mammalian DNA replication origins may be regulated by epigenetic changes in chromatin structure. The Epstein-Barr virus (EBV) origin of plasmid replication (OriP) uses the cellular licensing machinery to regulate replication during latent infection of human cells. We found that the minimal replicator sequence of OriP, referred to as the dyad symmetry (DS), is flanked by nucleosomes. These nucleosomes were subject to cell cycle-dependent chromatin remodeling and histone modifications. Restriction enzyme accessibility assay indicated that the DS-bounded nucleosomes were remodeled in late G1. Remarkably, histone H3 acetylation of DS-bounded nucleosomes decreased during late G1, coinciding with nucleosome remodeling and MCM3 loading, and preceding the onset of DNA replication. The ATP-dependent chromatin-remodeling factor SNF2h was also recruited to DS in late G1, and formed a stable complex with HDAC2 at DS. siRNA depletion of SNF2h reduced G1-specific nucleosome remodeling, histone deacetylation, and MCM3 loading at DS. We conclude that an SNF2h-HDAC1/2 complex coordinates G1-specific chromatin remodeling and histone deacetylation with the DNA replication initiation process at OriP.
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Affiliation(s)
- Jing Zhou
- The Wistar Institute, Philadelphia, PA, USA
| | | | - Zhong Deng
- The Wistar Institute, Philadelphia, PA, USA
| | | | - Mark-Peter Spindler
- Department of Gene Vectors, GSF-National Research Center for Environment and Health, Munich, Germany
| | - Aloys Schepers
- Department of Gene Vectors, GSF-National Research Center for Environment and Health, Munich, Germany
| | - Paul M Lieberman
- The Wistar Institute, Philadelphia, PA, USA
- The Wistar Institute, 3601 Spruce Street, Philadelphia, PA 19104, USA. Tel.: +1 215 898 9491; Fax: +1 215 898 0663; E-mail:
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12
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Green BM, Li JJ. Loss of rereplication control in Saccharomyces cerevisiae results in extensive DNA damage. Mol Biol Cell 2004; 16:421-32. [PMID: 15537702 PMCID: PMC539184 DOI: 10.1091/mbc.e04-09-0833] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
To maintain genome stability, the entire genome of a eukaryotic cell must be replicated once and only once per cell cycle. In many organisms, multiple overlapping mechanisms block rereplication, but the consequences of deregulating these mechanisms are poorly understood. Here, we show that disrupting these controls in the budding yeast Saccharomyces cerevisiae rapidly blocks cell proliferation. Rereplicating cells activate the classical DNA damage-induced checkpoint response, which depends on the BRCA1 C-terminus checkpoint protein Rad9. In contrast, Mrc1, a checkpoint protein required for recognition of replication stress, does not play a role in the response to rereplication. Strikingly, rereplicating cells accumulate subchromosomal DNA breakage products. These rapid and severe consequences suggest that even limited and sporadic rereplication could threaten the genome with significant damage. Hence, even subtle disruptions in the cell cycle regulation of DNA replication may predispose cells to the genomic instability associated with tumorigenesis.
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Affiliation(s)
- Brian M Green
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94143-2200, USA
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13
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Nabatiyan A, Krude T. Silencing of chromatin assembly factor 1 in human cells leads to cell death and loss of chromatin assembly during DNA synthesis. Mol Cell Biol 2004; 24:2853-62. [PMID: 15024074 PMCID: PMC371118 DOI: 10.1128/mcb.24.7.2853-2862.2004] [Citation(s) in RCA: 95] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In eukaryotic cells, chromatin serves as the physiological template for gene transcription, DNA replication, and repair. Chromatin assembly factor 1 (CAF-1) is the prime candidate protein to mediate assembly of newly replicated DNA into chromatin. To investigate the physiological role of CAF-1 in vivo, we used RNA interference (RNAi) to silence the 60-kDa subunit of CAF-1 (p60) in human cells. Transfection of a small interfering RNA (siRNA) directed against p60 resulted in efficient silencing of p60 expression within 24 h. This silencing led to an induction of programmed cell death in proliferating but not in quiescent human cells. Concomitantly, proliferating cells lacking p60 accumulated DNA double-strand breaks and increased levels of the phosphorylated histone H2A.X. Nuclear extracts from cells lacking p60 exhibited a 10-fold reduction of nucleosome assembly activity during DNA synthesis, which was restored upon addition of recombinant p60 protein. Nascent chromatin in cell nuclei lacking p60 showed significantly increased nuclease sensitivity, indicating chromatin assembly defects during DNA synthesis in vivo. Collectively, these data identify CAF-1 as an essential factor not only for S-phase-specific chromatin assembly but also for proliferating cell viability.
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Affiliation(s)
- Arman Nabatiyan
- Department of Zoology, University of Cambridge, Cambridge CB2 3EJ, United Kingdom
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14
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Prasanth SG, Méndez J, Prasanth KV, Stillman B. Dynamics of pre-replication complex proteins during the cell division cycle. Philos Trans R Soc Lond B Biol Sci 2004; 359:7-16. [PMID: 15065651 PMCID: PMC1693299 DOI: 10.1098/rstb.2003.1360] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Replication of the human genome every time a cell divides is a highly coordinated process that ensures accurate and efficient inheritance of the genetic information. The molecular mechanism that guarantees that many origins of replication fire only once per cell-cycle has been the area of intense research. The origin recognition complex (ORC) marks the position of replication origins in the genome and serves as the landing pad for the assembly of a multiprotein, pre-replicative complex (pre-RC) at the origins, consisting of ORC, cell division cycle 6 (Cdc6), Cdc10-dependent transcript (Cdt1) and mini-chromosome maintenance (MCM) proteins. The MCM proteins serve as key participants in the mechanism that limits eukaryotic DNA replication to once-per-cell-cycle and its binding to the chromatin marks the final step of pre-RC formation, a process referred to as 'replication licensing'. We present data demonstrating how the MCM proteins associate with the chromatin during the G1 phase, probably defining pre-RCs and then anticipate replication fork movement in a precisely coordinated manner during the S phase of the cell cycle. The process of DNA replication must also be carefully coordinated with other cell-cycle processes including mitosis and cytokinesis. Some of the proteins that control initiation of DNA replication are likely to interact with the pathways that control these important cell-cycle transitions. Herein, we discuss the participation of human ORC proteins in other vital functions, in addition to their bona fide roles in replication.
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Affiliation(s)
- Supriya G Prasanth
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724, USA
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