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Nuclear Chaperone ASF1 is Required for Gametogenesis in Arabidopsis thaliana. Sci Rep 2019; 9:13959. [PMID: 31562367 PMCID: PMC6764951 DOI: 10.1038/s41598-019-50450-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Accepted: 09/11/2019] [Indexed: 12/31/2022] Open
Abstract
Sexual reproduction in flowering plants is distinct from that in animals since gametogenesis requires production of haploid spores, which divide and differentiate into specialised gametophyte structures. Anti-Silencing Function 1 (ASF1) is a histone H3/H4 chaperone involved in chromatin remodeling during cell division, which we have found plays a critical role in gametophyte development in Arabidopsis thaliana. Using mutant alleles for the two ASF1 homologs, asf1a and asf1b, we show that ASF1 is required for successful development of gametophytes and acquisition of fertilisation competency. On the female side, reproductive failure is caused by aberrant development of ovules, leading to gamete degeneration. On the male side, we show both in vitro and in vivo that asf1 mutant pollen tube growth is stunted, limiting fertilisation to ovules nearest the stigma. Consistent with ASF1 importance in gametogenesis, we show that ASF1A and ASF1B are expressed throughout female and male gametogenesis. We show that the gametogenesis defects can be corrected by ASF1A and ASF1B transgenes, and that ASF1A and ASF1B act redundantly. Thus, in contrast to the role of ASF1 in sporophytic cell cycle progression, our data indicate that during reproduction, ASF1 is required for the precise nuclei differentiation necessary for gametophyte maturation and fertilisation.
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2
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Asf1a resolves bivalent chromatin domains for the induction of lineage-specific genes during mouse embryonic stem cell differentiation. Proc Natl Acad Sci U S A 2018; 115:E6162-E6171. [PMID: 29915027 DOI: 10.1073/pnas.1801909115] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Bivalent chromatin domains containing repressive H3K27me3 and active H3K4me3 modifications are barriers for the expression of lineage-specific genes in ES cells and must be resolved for the transcription induction of these genes during differentiation, a process that remains largely unknown. Here, we show that Asf1a, a histone chaperone involved in nucleosome assembly and disassembly, regulates the resolution of bivalent domains and activation of lineage-specific genes during mouse ES cell differentiation. Deletion of Asf1a does not affect the silencing of pluripotent genes, but compromises the expression of lineage-specific genes during ES cell differentiation. Mechanistically, the Asf1a-histone interaction, but not the role of Asf1a in nucleosome assembly, is required for gene transcription. Asf1a is recruited to several bivalent promoters, partially through association with transcription factors, and mediates nucleosome disassembly during differentiation. We suggest that Asf1a-mediated nucleosome disassembly provides a means for resolution of bivalent domain barriers for induction of lineage-specific genes during differentiation.
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3
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González-Arzola K, Díaz-Quintana A, Rivero-Rodríguez F, Velázquez-Campoy A, De la Rosa MA, Díaz-Moreno I. Histone chaperone activity of Arabidopsis thaliana NRP1 is blocked by cytochrome c. Nucleic Acids Res 2017; 45:2150-2165. [PMID: 27924001 PMCID: PMC5389710 DOI: 10.1093/nar/gkw1215] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Accepted: 11/22/2016] [Indexed: 12/21/2022] Open
Abstract
Higher-order plants and mammals use similar mechanisms to repair and tolerate oxidative DNA damage. Most studies on the DNA repair process have focused on yeast and mammals, in which histone chaperone-mediated nucleosome disassembly/reassembly is essential for DNA to be accessible to repair machinery. However, little is known about the specific role and modulation of histone chaperones in the context of DNA damage in plants. Here, the histone chaperone NRP1, which is closely related to human SET/TAF-Iβ, was found to exhibit nucleosome assembly activity in vitro and to accumulate in the chromatin of Arabidopsis thaliana after DNA breaks. In addition, this work establishes that NRP1 binds to cytochrome c, thereby preventing the former from binding to histones. Since NRP1 interacts with cytochrome c at its earmuff domain, that is, its histone-binding domain, cytochrome c thus competes with core histones and hampers the activity of NRP1 as a histone chaperone. Altogether, the results obtained indicate that the underlying molecular mechanisms in nucleosome disassembly/reassembly are highly conserved throughout evolution, as inferred from the similar inhibition of plant NRP1 and human SET/TAF-Iβ by cytochrome c during DNA damage response.
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Affiliation(s)
- Katiuska González-Arzola
- Institute for Chemical Research (IIQ), Isla de la Cartuja Scientific Research Centre (cicCartuja), University of Seville-Spanish National Research Council (CSIC), Avda. Américo Vespucio 49, 41092 Sevilla, Spain
| | - Antonio Díaz-Quintana
- Institute for Chemical Research (IIQ), Isla de la Cartuja Scientific Research Centre (cicCartuja), University of Seville-Spanish National Research Council (CSIC), Avda. Américo Vespucio 49, 41092 Sevilla, Spain
| | - Francisco Rivero-Rodríguez
- Institute for Chemical Research (IIQ), Isla de la Cartuja Scientific Research Centre (cicCartuja), University of Seville-Spanish National Research Council (CSIC), Avda. Américo Vespucio 49, 41092 Sevilla, Spain
| | - Adrián Velázquez-Campoy
- Institute for Biocomputation and Physics of Complex Systems (BIFI), Joint Unit Institute of Physical Chemistry Rocasolano (IQFR)-BIFI-Spanish National Research Council (CSIC), University of Zaragoza, Mariano Esquillor s/n, 50018 Zaragoza, Spain.,Department of Biochemistry and Molecular and Cellular Biology, University of Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza (Spain); and Aragon Agency for Research and Development (ARAID), Regional Government of Aragon, Maria de Luna 11, 50018 Zaragoza, Spain
| | - Miguel A De la Rosa
- Institute for Chemical Research (IIQ), Isla de la Cartuja Scientific Research Centre (cicCartuja), University of Seville-Spanish National Research Council (CSIC), Avda. Américo Vespucio 49, 41092 Sevilla, Spain
| | - Irene Díaz-Moreno
- Institute for Chemical Research (IIQ), Isla de la Cartuja Scientific Research Centre (cicCartuja), University of Seville-Spanish National Research Council (CSIC), Avda. Américo Vespucio 49, 41092 Sevilla, Spain
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Warren C, Shechter D. Fly Fishing for Histones: Catch and Release by Histone Chaperone Intrinsically Disordered Regions and Acidic Stretches. J Mol Biol 2017; 429:2401-2426. [PMID: 28610839 DOI: 10.1016/j.jmb.2017.06.005] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 06/05/2017] [Accepted: 06/06/2017] [Indexed: 01/21/2023]
Abstract
Chromatin is the complex of eukaryotic DNA and proteins required for the efficient compaction of the nearly 2-meter-long human genome into a roughly 10-micron-diameter cell nucleus. The fundamental repeating unit of chromatin is the nucleosome: 147bp of DNA wrapped about an octamer of histone proteins. Nucleosomes are stable enough to organize the genome yet must be dynamically displaced and reassembled to allow access to the underlying DNA for transcription, replication, and DNA damage repair. Histone chaperones are a non-catalytic group of proteins that are central to the processes of nucleosome assembly and disassembly and thus the fluidity of the ever-changing chromatin landscape. Histone chaperones are responsible for binding the highly basic histone proteins, shielding them from non-specific interactions, facilitating their deposition onto DNA, and aiding in their eviction from DNA. Although most histone chaperones perform these common functions, recent structural studies of many different histone chaperones reveal that there are few commonalities in their folds. Importantly, sequence-based predictions show that histone chaperones are highly enriched in intrinsically disordered regions (IDRs) and acidic stretches. In this review, we focus on the molecular mechanisms underpinning histone binding, selectivity, and regulation of these highly dynamic protein regions. We highlight new evidence suggesting that IDRs are often critical for histone chaperone function and play key roles in chromatin assembly and disassembly pathways.
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Affiliation(s)
- Christopher Warren
- Department of Biochemistry, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA
| | - David Shechter
- Department of Biochemistry, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA.
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5
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Tscherner M, Zwolanek F, Jenull S, Sedlazeck FJ, Petryshyn A, Frohner IE, Mavrianos J, Chauhan N, von Haeseler A, Kuchler K. The Candida albicans Histone Acetyltransferase Hat1 Regulates Stress Resistance and Virulence via Distinct Chromatin Assembly Pathways. PLoS Pathog 2015; 11:e1005218. [PMID: 26473952 PMCID: PMC4608838 DOI: 10.1371/journal.ppat.1005218] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Accepted: 09/21/2015] [Indexed: 01/14/2023] Open
Abstract
Human fungal pathogens like Candida albicans respond to host immune surveillance by rapidly adapting their transcriptional programs. Chromatin assembly factors are involved in the regulation of stress genes by modulating the histone density at these loci. Here, we report a novel role for the chromatin assembly-associated histone acetyltransferase complex NuB4 in regulating oxidative stress resistance, antifungal drug tolerance and virulence in C. albicans. Strikingly, depletion of the NuB4 catalytic subunit, the histone acetyltransferase Hat1, markedly increases resistance to oxidative stress and tolerance to azole antifungals. Hydrogen peroxide resistance in cells lacking Hat1 results from higher induction rates of oxidative stress gene expression, accompanied by reduced histone density as well as subsequent increased RNA polymerase recruitment. Furthermore, hat1Δ/Δ cells, despite showing growth defects in vitro, display reduced susceptibility to reactive oxygen-mediated killing by innate immune cells. Thus, clearance from infected mice is delayed although cells lacking Hat1 are severely compromised in killing the host. Interestingly, increased oxidative stress resistance and azole tolerance are phenocopied by the loss of histone chaperone complexes CAF-1 and HIR, respectively, suggesting a central role for NuB4 in the delivery of histones destined for chromatin assembly via distinct pathways. Remarkably, the oxidative stress phenotype of hat1Δ/Δ cells is a species-specific trait only found in C. albicans and members of the CTG clade. The reduced azole susceptibility appears to be conserved in a wider range of fungi. Thus, our work demonstrates how highly conserved chromatin assembly pathways can acquire new functions in pathogenic fungi during coevolution with the host. Candida albicans is the most prevalent fungal pathogen infecting humans, causing life-threatening infections in immunocompromised individuals. Host immune surveillance imposes stress conditions upon C. albicans, to which it has to adapt quickly to escape host killing. This can involve regulation of specific genes requiring disassembly and reassembly of histone proteins, around which DNA is wrapped to form the basic repeat unit of eukaryotic chromatin—the nucleosome. Here, we discover a novel function for the chromatin assembly-associated histone acetyltransferase complex NuB4 in oxidative stress response, antifungal drug tolerance as well as in fungal virulence. The NuB4 complex modulates the induction kinetics of hydrogen peroxide-induced genes. Furthermore, NuB4 negatively regulates susceptibility to killing by immune cells and thereby slowing the clearing from infected mice in vivo. Remarkably, the oxidative stress resistance seems restricted to C. albicans and closely related species, which might have acquired this function during coevolution with the host.
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Affiliation(s)
- Michael Tscherner
- Department for Medical Biochemistry, Medical University of Vienna, Max F. Perutz Laboratories, Campus Vienna Biocenter, Vienna, Austria
| | - Florian Zwolanek
- Department for Medical Biochemistry, Medical University of Vienna, Max F. Perutz Laboratories, Campus Vienna Biocenter, Vienna, Austria
| | - Sabrina Jenull
- Department for Medical Biochemistry, Medical University of Vienna, Max F. Perutz Laboratories, Campus Vienna Biocenter, Vienna, Austria
| | - Fritz J. Sedlazeck
- Center for Integrative Bioinformatics Vienna, Max F. Perutz Laboratories, University of Vienna, Medical University of Vienna, Campus Vienna Biocenter, Vienna, Austria
| | - Andriy Petryshyn
- Department for Medical Biochemistry, Medical University of Vienna, Max F. Perutz Laboratories, Campus Vienna Biocenter, Vienna, Austria
| | - Ingrid E. Frohner
- Department for Medical Biochemistry, Medical University of Vienna, Max F. Perutz Laboratories, Campus Vienna Biocenter, Vienna, Austria
| | - John Mavrianos
- Public Health Research Institute, New Jersey Medical School - Rutgers, The State University of New Jersey, Newark, New Jersey, United States of America
| | - Neeraj Chauhan
- Public Health Research Institute, New Jersey Medical School - Rutgers, The State University of New Jersey, Newark, New Jersey, United States of America
| | - Arndt von Haeseler
- Center for Integrative Bioinformatics Vienna, Max F. Perutz Laboratories, University of Vienna, Medical University of Vienna, Campus Vienna Biocenter, Vienna, Austria
| | - Karl Kuchler
- Department for Medical Biochemistry, Medical University of Vienna, Max F. Perutz Laboratories, Campus Vienna Biocenter, Vienna, Austria
- * E-mail:
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6
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Gurard-Levin ZA, Quivy JP, Almouzni G. Histone chaperones: assisting histone traffic and nucleosome dynamics. Annu Rev Biochem 2015; 83:487-517. [PMID: 24905786 DOI: 10.1146/annurev-biochem-060713-035536] [Citation(s) in RCA: 214] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The functional organization of eukaryotic DNA into chromatin uses histones as components of its building block, the nucleosome. Histone chaperones, which are proteins that escort histones throughout their cellular life, are key actors in all facets of histone metabolism; they regulate the supply and dynamics of histones at chromatin for its assembly and disassembly. Histone chaperones can also participate in the distribution of histone variants, thereby defining distinct chromatin landscapes of importance for genome function, stability, and cell identity. Here, we discuss our current knowledge of the known histone chaperones and their histone partners, focusing on histone H3 and its variants. We then place them into an escort network that distributes these histones in various deposition pathways. Through their distinct interfaces, we show how they affect dynamics during DNA replication, DNA damage, and transcription, and how they maintain genome integrity. Finally, we discuss the importance of histone chaperones during development and describe how misregulation of the histone flow can link to disease.
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Affiliation(s)
- Zachary A Gurard-Levin
- Institut Curie, Centre de Recherche; CNRS UMR 3664; Equipe Labellisée, Ligue contre le Cancer; and Université Pierre et Marie Curie, Paris F-75248, France;
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7
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Tousled-like kinases phosphorylate Asf1 to promote histone supply during DNA replication. Nat Commun 2014; 5:3394. [PMID: 24598821 PMCID: PMC3977046 DOI: 10.1038/ncomms4394] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2013] [Accepted: 02/05/2014] [Indexed: 12/25/2022] Open
Abstract
During DNA replication, nucleosomes are rapidly assembled on newly synthesized DNA to restore chromatin organization. Asf1, a key histone H3-H4 chaperone required for this process, is phosphorylated by Tousled-Like Kinases (TLKs). Here, we identify TLK phosphorylation sites by mass spectrometry and dissect how phosphorylation impacts on human Asf1 function. The divergent C-terminal tail of Asf1a is phosphorylated at several sites and this is required for timely progression through S phase. Consistent with this, biochemical analysis of wild-type and phosphomimetic Asf1a shows that phosphorylation enhances binding to histones and the downstream chaperones CAF-1 and HIRA. Moreover, we find that TLK phosphorylation of Asf1a is induced in cells experiencing deficiency of new histones and that TLK interaction with Asf1a involves its histone-binding pocket. We thus propose that TLK signaling promotes histone supply in S phase by targeting histone-free Asf1 and stimulating its ability to shuttle histones to sites of chromatin assembly.
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8
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Annunziato AT. Assembling chromatin: the long and winding road. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2014; 1819:196-210. [PMID: 24459722 DOI: 10.1016/j.bbagrm.2011.07.005] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
It has been over 35 years since the acceptance of the "chromatin subunit" hypothesis, and the recognition that nucleosomes are the fundamental repeating units of chromatin fibers. Major subjects of inquiry in the intervening years have included the steps involved in chromatin assembly, and the chaperones that escort histones to DNA. The following commentary offers an historical perspective on inquiries into the processes by which nucleosomes are assembled on replicating and nonreplicating chromatin. This article is part of a Special Issue entitled: Histone chaperones and Chromatin assembly.
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Towards a mechanism for histone chaperones. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2014; 1819:211-221. [PMID: 24459723 DOI: 10.1016/j.bbagrm.2011.07.007] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Histone chaperones can be broadly defined as histone-binding proteins that influence chromatin dynamics in an ATP-independent manner. Their existence reflects the importance of chromatin homeostasis and the unique and unusual biochemistry of the histone proteins. Histone supply and demand at chromatin is regulated by a network of structurally and functionally diverse histone chaperones. At the core of this network is a mechanistic variability that is only beginning to be appreciated. In this review, we highlight the challenges in determining histone chaperone mechanism and discuss possible mechanisms in the context of nucleosome thermodynamics. We discuss how histone chaperones prevent promiscuous histone interactions, and consider if this activity represents the full extent of histone chaperone function in governing chromatin dynamics. This article is part of a Special Issue entitled: Histone chaperones and Chromatin assembly.
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10
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Pascoalino B, Dindar G, Vieira-da-Rocha JP, Machado CR, Janzen CJ, Schenkman S. Characterization of two different Asf1 histone chaperones with distinct cellular localizations and functions in Trypanosoma brucei. Nucleic Acids Res 2013; 42:2906-18. [PMID: 24322299 PMCID: PMC3950673 DOI: 10.1093/nar/gkt1267] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The anti-silencing function protein 1 (Asf1) is a chaperone that forms a complex with histones H3 and H4 facilitating dimer deposition and removal from chromatin. Most eukaryotes possess two different Asf1 chaperones but their specific functions are still unknown. Trypanosomes, a group of early-diverged eukaryotes, also have two, but more divergent Asf1 paralogs than Asf1 of higher eukaryotes. To unravel possible different functions, we characterized the two Asf1 proteins in Trypanosoma brucei. Asf1A is mainly localized in the cytosol but translocates to the nucleus in S phase. In contrast, Asf1B is predominantly localized in the nucleus, as described for other organisms. Cytosolic Asf1 knockdown results in accumulation of cells in early S phase of the cell cycle, whereas nuclear Asf1 knockdown arrests cells in S/G2 phase. Overexpression of cytosolic Asf1 increases the levels of histone H3 and H4 acetylation. In contrast to cytosolic Asf1, overexpression of nuclear Asf1 causes less pronounced growth defects in parasites exposed to genotoxic agents, prompting a function in chromatin remodeling in response to DNA damage. Only the cytosolic Asf1 interacts with recombinant H3/H4 dimers in vitro. These findings denote the early appearance in evolution of distinguishable functions for the two Asf1 chaperons in trypanosomes.
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Affiliation(s)
- Bruno Pascoalino
- Depto. de Microbiologia, Imunologia e Parasitologia, UNIFESP, Rua Pedro de Toledo 669 L6A, São Paulo, São Paulo 04039-032, Brazil, Lehrstuhl für Zell- und Entwicklungsbiologie, Theodor-Boveri-Institut, Biozentrum der Universität Würzburg, Am Hubland, 97074 Würzburg, Germany and Depto. de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, CP 4861, 30161-970, Belo Horizonte, Minas Gerais, Brazil
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11
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The C terminus of the histone chaperone Asf1 cross-links to histone H3 in yeast and promotes interaction with histones H3 and H4. Mol Cell Biol 2012. [PMID: 23184661 DOI: 10.1128/mcb.01053-12] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The central histone H3/H4 chaperone Asf1 comprises a highly conserved globular core and a divergent C-terminal tail. While the function and structure of the Asf1 core are well known, the function of the tail is less well understood. Here, we have explored the role of the yeast (yAsf1) and human (hAsf1a and hAsf1b) Asf1 tails in Saccharomyces cerevisiae. We show, using a photoreactive, unnatural amino acid, that Asf1 tail residue 210 cross-links to histone H3 in vivo and, further, that loss of C-terminal tail residues 211 to 279 weakens yAsf1-histone binding affinity in vitro nearly 200-fold. Via several yAsf1 C-terminal truncations and yeast-human chimeric proteins, we found that truncations at residue 210 increase transcriptional silencing and that the hAsf1a tail partially substitutes for full-length yAsf1 with respect to silencing but that full-length hAsf1b is a better overall substitute for full-length yAsf1. In addition, we show that the C-terminal tail of Asf1 is phosphorylated at T270 in yeast. Loss of this phosphorylation site does not prevent coimmunoprecipitation of yAsf1 and Rad53 from yeast extracts, whereas amino acid residue substitutions at the Asf1-histone H3/H4 interface do. Finally, we show that residue substitutions in yAsf1 near the CAF-1/HIRA interface also influence yAsf1's function in silencing.
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12
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De Benedetti A. The Tousled-Like Kinases as Guardians of Genome Integrity. ISRN MOLECULAR BIOLOGY 2012; 2012:627596. [PMID: 23869254 PMCID: PMC3712517 DOI: 10.5402/2012/627596] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The Tousled-like kinases (TLKs) function in processes of chromatin assembly, including replication, transcription, repair, and chromosome segregation. TLKs interact specifically (and phosphorylate) with the chromatin assembly factor Asf1, a histone H3-H4 chaperone, histone H3 itself at Ser10, and also Rad9, a key protein involved in DNA repair and cell cycle signaling following DNA damage. These interactions are believed to be responsible for the action of TLKs in double-stranded break repair and radioprotection and also in the propagation of the DNA damage response. Hence, I propose that TLKs play key roles in maintenance of genome integrity in many organisms of both kingdoms. In this paper, I highlight key issues of the known roles of these proteins, particularly in the context of DNA repair (IR and UV), their possible relevance to genome integrity and cancer development, and as possible targets for intervention in cancer management.
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Affiliation(s)
- Arrigo De Benedetti
- Department of Biochemistry and Molecular Biology and Feist-Weiller Cancer Center, Louisiana State University Health Sciences Center, 1501 Kings Highway, Shreveport, LA 71130, USA
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Gesing S, Schindler D, Fränzel B, Wolters D, Nowrousian M. The histone chaperone ASF1 is essential for sexual development in the filamentous fungus Sordaria macrospora. Mol Microbiol 2012; 84:748-65. [PMID: 22463819 DOI: 10.1111/j.1365-2958.2012.08058.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Ascomycetes develop four major types of fruiting bodies that share a common ancestor, and a set of common core genes most likely controls this process. One way to identify such genes is to search for conserved expression patterns. We analysed microarray data of Fusarium graminearum and Sordaria macrospora, identifying 78 genes with similar expression patterns during fruiting body development. One of these genes was asf1 (anti-silencing function 1), encoding a predicted histone chaperone. asf1 expression is also upregulated during development in the distantly related ascomycete Pyronema confluens. To test whether asf1 plays a role in fungal development, we generated an S. macrospora asf1 deletion mutant. The mutant is sterile and can be complemented to fertility by transformation with the wild-type asf1 and its P. confluens homologue. An ASF1-EGFP fusion protein localizes to the nucleus. By tandem-affinity purification/mass spectrometry as well as yeast two-hybrid analysis, we identified histones H3 and H4 as ASF1 interaction partners. Several developmental genes are dependent on asf1 for correct transcriptional expression. Deletion of the histone chaperone genes rtt106 and cac2 did not cause any developmental phenotypes. These data indicate that asf1 of S. macrospora encodes a conserved histone chaperone that is required for fruiting body development.
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Affiliation(s)
- Stefan Gesing
- Lehrstuhl für Allgemeine und Molekulare Botanik, Ruhr-Universität Bochum, Universitätsstraße 150, 44780 Bochum, Germany
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14
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Tanae K, Horiuchi T, Matsuo Y, Katayama S, Kawamukai M. Histone chaperone Asf1 plays an essential role in maintaining genomic stability in fission yeast. PLoS One 2012; 7:e30472. [PMID: 22291963 PMCID: PMC3266922 DOI: 10.1371/journal.pone.0030472] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2011] [Accepted: 12/20/2011] [Indexed: 01/28/2023] Open
Abstract
The histone H3-H4 chaperone Asf1 is involved in chromatin assembly (or disassembly), histone exchange, regulation of transcription, and chromatin silencing in several organisms. To investigate the essential functions of Asf1 in Schizosaccharomyces pombe, asf1-ts mutants were constructed by random mutagenesis using PCR. One mutant (asf1-33(ts)) was mated with mutants in 77 different kinase genes to identify synthetic lethal combinations. The asf1-33 mutant required the DNA damage checkpoint factors Chk1 and Rad3 for its survival at the restrictive temperature. Chk1, but not Cds1, was phosphorylated in the asf1-33 mutant at the restrictive temperature, indicating that the DNA damage checkpoint was activated in the asf1-33 mutant. DNA damage occured in the asf1-33 mutant, with degradation of the chromosomal DNA observed through pulse-field gel electrophoresis and the formation of Rad22 foci. Sensitivity to micrococcal nuclease in the asf1-33 mutant was increased compared to the asf1+ strain at the restrictive temperature, suggesting that asf1 mutations also caused a defect in overall chromatin structure. The Asf1-33 mutant protein was mislocalized and incapable of binding histones. Furthermore, histone H3 levels at the centromeric outer repeat region were decreased in the asf1-33 mutant and heterochromatin structure was impaired. Finally, sim3, which encodes a CenH3 histone chaperone, was identified as a strong suppressor of the asf1-33 mutant. Taken together, these results clearly indicate that Asf1 plays an essential role in maintaining genomic stability in S. pombe.
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Affiliation(s)
- Katsuhiro Tanae
- Department of Life Science and Biotechnology, Faculty of Life and Environmental Science, Shimane University, Matsue, Japan
| | - Tomitaka Horiuchi
- Department of Life Science and Biotechnology, Faculty of Life and Environmental Science, Shimane University, Matsue, Japan
| | - Yuzy Matsuo
- Department of Life Science and Biotechnology, Faculty of Life and Environmental Science, Shimane University, Matsue, Japan
| | - Satoshi Katayama
- Department of Life Science and Biotechnology, Faculty of Life and Environmental Science, Shimane University, Matsue, Japan
| | - Makoto Kawamukai
- Department of Life Science and Biotechnology, Faculty of Life and Environmental Science, Shimane University, Matsue, Japan
- * E-mail:
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15
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Yamane K, Mizuguchi T, Cui B, Zofall M, Noma KI, Grewal SIS. Asf1/HIRA facilitate global histone deacetylation and associate with HP1 to promote nucleosome occupancy at heterochromatic loci. Mol Cell 2011; 41:56-66. [PMID: 21211723 DOI: 10.1016/j.molcel.2010.12.009] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2010] [Revised: 11/03/2010] [Accepted: 11/24/2010] [Indexed: 12/21/2022]
Abstract
Heterochromatin impacts various nuclear processes by providing a recruiting platform for diverse chromosomal proteins. In fission yeast, HP1 proteins Chp2 and Swi6, which bind to methylated histone H3 lysine 9, associate with SHREC (Snf2/HDAC repressor complex) and Clr6 histone deacetylases (HDACs) involved in heterochromatic silencing. However, heterochromatic silencing machinery is not fully defined. We describe a histone chaperone complex containing Asf1 and HIRA that spreads across silenced domains via its association with Swi6 to enforce transcriptional silencing. Asf1 functions in concert with a Clr6 HDAC complex to silence heterochromatic repeats, and it suppresses antisense transcription by promoting histone deacetylation. Furthermore, we demonstrate that Asf1 and SHREC facilitate nucleosome occupancy at heterochromatic regions but TFIIIC transcription factor binding sites within boundary elements are refractory to these factors. These analyses uncover a role for Asf1 in global histone deacetylation and suggest that HP1-associated histone chaperone promotes nucleosome occupancy to assemble repressive heterochromatin.
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Affiliation(s)
- Kenichi Yamane
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, Bethesda, MD 20892, USA
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16
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Matsuo Y, Kishimoto H, Tanae K, Kitamura K, Katayama S, Kawamukai M. Nuclear protein quality is regulated by the ubiquitin-proteasome system through the activity of Ubc4 and San1 in fission yeast. J Biol Chem 2011; 286:13775-90. [PMID: 21324894 DOI: 10.1074/jbc.m110.169953] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Eukaryotic cells monitor and maintain protein quality through a set of protein quality control (PQC) systems whose role is to minimize the harmful effects of the accumulation of aberrant proteins. Although these PQC systems have been extensively studied in the cytoplasm, nuclear PQC systems are not well understood. The present work shows the existence of a nuclear PQC system mediated by the ubiquitin-proteasome system in the fission yeast Schizosaccharomyces pombe. Asf1-30, a mutant form of the histone chaperone Asf1, was used as a model substrate for the study of the nuclear PQC. A temperature-sensitive Asf1-30 protein localized to the nucleus was selectively degraded by the ubiquitin-proteasome system. The Asf1-30 mutant protein was highly ubiquitinated at higher temperatures, and it remained stable in an mts2-1 mutant, which lacks proteasome activity. The E2 enzyme Ubc4 was identified among 11 candidate proteins as the ubiquitin-conjugating enzyme in this system, and San1 was selected among 100 candidates as the ubiquitin ligase (E3) targeting Asf1-30 for degradation. San1, but not other nuclear E3s, showed specificity for the mutant nuclear Asf1-30, but did not show activity against wild-type Asf1. These data clearly showed that the aberrant nuclear protein was degraded by a defined set of E1-E2-E3 enzymes through the ubiquitin-proteasome system. The data also show, for the first time, the presence of a nuclear PQC system in fission yeast.
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Affiliation(s)
- Yuzy Matsuo
- Department of Life Science and Biotechnology, Faculty of Life and Environmental Science, Shimane University, 1060 Nishikawatsu, Matsue 690-8504, Japan
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17
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Wakamori M, Umehara T, Yokoyama S. A series of bacterial co-expression vectors with rare-cutter recognition sequences. Protein Expr Purif 2010; 74:88-98. [DOI: 10.1016/j.pep.2010.06.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2010] [Revised: 06/22/2010] [Accepted: 06/23/2010] [Indexed: 10/19/2022]
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18
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Tochio N, Umehara T, Munemasa Y, Suzuki T, Sato S, Tsuda K, Koshiba S, Kigawa T, Nagai R, Yokoyama S. Solution structure of histone chaperone ANP32B: interaction with core histones H3-H4 through its acidic concave domain. J Mol Biol 2010; 401:97-114. [PMID: 20538007 DOI: 10.1016/j.jmb.2010.06.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2010] [Revised: 05/27/2010] [Accepted: 06/01/2010] [Indexed: 01/08/2023]
Abstract
Eukaryotic gene expression is regulated by histone deposition onto and eviction from nucleosomes, which are mediated by several chromatin-modulating factors. Among them, histone chaperones are key factors that facilitate nucleosome assembly. Acidic nuclear phosphoprotein 32B (ANP32B) belongs to the ANP32 family, which shares N-terminal leucine-rich repeats (LRRs) and a C-terminal variable anionic region. The C-terminal region functions as an inhibitor of histone acetylation, but the functional roles of the LRR domain in chromatin regulation have remained elusive. Here, we report that the LRR domain of ANP32B possesses histone chaperone activity and forms a curved structure with a parallel beta-sheet on the concave side and mostly helical elements on the convex side. Our analyses revealed that the interaction of ANP32B with the core histones H3-H4 occurs on its concave side, and both the acidic and hydrophobic residues that compose the concave surface are critical for histone binding. These results provide a structural framework for understanding the functional mechanisms of acidic histone chaperones.
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Affiliation(s)
- Naoya Tochio
- RIKEN Systems and Structural Biology Center, 1-7-22 Suehiro-cho, Tsurumi, Yokohama 230-0045, Japan
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19
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The histone shuffle: histone chaperones in an energetic dance. Trends Biochem Sci 2010; 35:476-89. [PMID: 20444609 DOI: 10.1016/j.tibs.2010.04.001] [Citation(s) in RCA: 138] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2010] [Revised: 03/30/2010] [Accepted: 04/05/2010] [Indexed: 11/22/2022]
Abstract
Our genetic information is tightly packaged into a rather ingenious nucleoprotein complex called chromatin in a manner that enables it to be rapidly accessed during genomic processes. Formation of the nucleosome, which is the fundamental unit of chromatin, occurs via a stepwise process that is reversed to enable the disassembly of nucleosomes. Histone chaperone proteins have prominent roles in facilitating these processes as well as in replacing old histones with new canonical histones or histone variants during the process of histone exchange. Recent structural, biophysical and biochemical studies have begun to shed light on the molecular mechanisms whereby histone chaperones promote chromatin assembly, disassembly and histone exchange to facilitate DNA replication, repair and transcription.
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20
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De Benedetti A. Tousled kinase TLK1B mediates chromatin assembly in conjunction with Asf1 regardless of its kinase activity. BMC Res Notes 2010; 3:68. [PMID: 20222959 PMCID: PMC2845150 DOI: 10.1186/1756-0500-3-68] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2010] [Accepted: 03/11/2010] [Indexed: 11/12/2022] Open
Abstract
Background The Tousled Like Kinases (TLKs) are involved in chromatin dynamics, including DNA replication and repair, transcription, and chromosome segregation. Indeed, the first two TLK1 substrates were identified as the histone H3 and Asf1 (a histone H3/H4 chaperone), which immediately suggested a function in chromatin remodeling. However, despite the straightforward assumption that TLK1 acts simply by phosphorylating its substrates and hence modifying their activity, TLK1 also acts as a chaperone. In fact, a kinase-dead (KD) mutant of TLK1B is functional in stimulating chromatin assembly in vitro. However, subtle effects of Asf1 phosphorylation are more difficult to probe in chromatin assembly assays. Not until very recently was the Asf1 site phosphorylated by TLK1 identified. This has allowed for probing directly the functionality of a site-directed mutant of Asf1 in chromatin assembly assays. Findings Addition of either wt or non-phosphorylatable mutant Asf1 to nuclear extract stimulates chromatin assembly on a plasmid. Similarly, TLK1B-KD stimulates chromatin assembly and it synergizes in reactions with supplemental Asf1 (wt or non-phosphorylatable mutant). Conclusions Although the actual function of TLKs as mediators of Asf1 activity cannot be easily studied in vivo, particularly since in mammalian cells there are two TLK genes and two Asf1 genes, we were able to study specifically the stimulation of chromatin assembly in vitro. In such assays, clearly the TLK1 kinase activity was not critical, as neither a non-phosphorylatable Asf1 nor use of the TLK1B-KD impaired the stimulation of nucleosome formation.
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Affiliation(s)
- Arrigo De Benedetti
- Department of Biochemistry and Molecular Biology and the Feist-Weiller Cancer Center, Louisiana State University Health Sciences Center, Shreveport, LA 71130, USA.
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21
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Simple and effective gap-repair cloning using short tracts of flanking homology in fission yeast. Biosci Biotechnol Biochem 2010; 74:685-9. [PMID: 20208336 DOI: 10.1271/bbb.90967] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Gap-repair cloning for plasmid construction in budding yeast is very effective and often used. In contrast, the same method is not widely used in fission yeast, because of a shortage of information on it. Here we describe simple and effective gap-repair cloning for plasmid construction using short tracts of flanking homology. By this method, we combined concentrated DNA fragments with short (20 bp) tracts of flanking homology with the marker gene or the pre-existing gene module. In addition, we found that this method can be applied to one-step cloning of multiple DNA fragments to construct a fusion gene.
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22
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Pilyugin M, Demmers J, Verrijzer CP, Karch F, Moshkin YM. Phosphorylation-mediated control of histone chaperone ASF1 levels by Tousled-like kinases. PLoS One 2009; 4:e8328. [PMID: 20016786 PMCID: PMC2791443 DOI: 10.1371/journal.pone.0008328] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2009] [Accepted: 11/24/2009] [Indexed: 11/19/2022] Open
Abstract
Histone chaperones are at the hub of a diverse interaction networks integrating a plethora of chromatin modifying activities. Histone H3/H4 chaperone ASF1 is a target for cell-cycle regulated Tousled-like kinases (TLKs) and both proteins cooperate during chromatin replication. However, the precise role of post-translational modification of ASF1 remained unclear. Here, we identify the TLK phosphorylation sites for both Drosophila and human ASF1 proteins. Loss of TLK-mediated phosphorylation triggers hASF1a and dASF1 degradation by proteasome-dependent and independent mechanisms respectively. Consistent with this notion, introduction of phosphorylation-mimicking mutants inhibits hASF1a and dASF1 degradation. Human hASF1b is also targeted for proteasome-dependent degradation, but its stability is not affected by phosphorylation indicating that other mechanisms are likely to be involved in control of hASF1b levels. Together, these results suggest that ASF1 cellular levels are tightly controlled by distinct pathways and provide a molecular mechanism for post-translational regulation of dASF1 and hASF1a by TLK kinases.
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Affiliation(s)
- Maxim Pilyugin
- Department of Zoology and National Research Center Frontiers in Genetics, University of Geneva, Geneva, Switzerland
| | - Jeroen Demmers
- Proteomics Center, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - C. Peter Verrijzer
- Department of Biochemistry, Center for Biomedical Genetics, Erasmus University, Rotterdam, The Netherlands
| | - Francois Karch
- Department of Zoology and National Research Center Frontiers in Genetics, University of Geneva, Geneva, Switzerland
- * E-mail: (FK); (YMM)
| | - Yuri M. Moshkin
- Department of Biochemistry, Center for Biomedical Genetics, Erasmus University, Rotterdam, The Netherlands
- * E-mail: (FK); (YMM)
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23
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Padmanabhan B, Kataoka K, Umehara T, Adachi N, Yokoyama S, Horikoshi M. Structural similarity between histone chaperone Cia1p/Asf1p and DNA-binding protein NF-kappaB. J Biochem 2009; 138:821-9. [PMID: 16428312 DOI: 10.1093/jb/mvi182] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The structural relationships between histone-binding proteins and DNA-binding proteins are important, since nucleosome-interacting factors possess histone-binding and/or DNA-binding components. S. cerevisiae (Sc) Cia1p/Asf1p, a homologue of human CIA (CCG1-interacting factor A), is the most evolutionarily conserved histone chaperone, which facilitates nucleosome assembly by interacting with the nucleosome entry site of the core histones H3/H4. The crystal structure of the evolutionarily conserved domain (residues 1-169) of Cia1p (ScCia1p-DeltaC2) was determined at 2.95 A resolution. The refined model contains 166 residues in the asymmetric unit. The overall tertiary structure resembles a beta-sandwich fold, and belongs to the "switched" immunoglobulin class of proteins. The crystal structure suggests that ScCia1p-DeltaC2 is structurally related to the DNA-binding proteins, such as NF-kappaB and its family members. This is the first examination of the structural similarities between a histone chaperone and DNA-binding proteins. We discuss the possibilities that the strands beta3 and beta4, which possess highly electronegative surface potentials, are the important regions for the interaction with core histones, and that the histone chaperone ScCia1p/Asf1p and the DNA-binding protein NF-kappaB may have evolved from the same prototypal protein class.
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Affiliation(s)
- Balasundaram Padmanabhan
- Horikoshi Gene Selector Project, Exploratory Research for Advanced Technology (ERATO), Japan Science and Technology Corporation (JST), 5-9-6 Tokodai, Tsukuba 300-2635
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24
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Malay AD, Umehara T, Matsubara-Malay K, Padmanabhan B, Yokoyama S. Crystal structures of fission yeast histone chaperone Asf1 complexed with the Hip1 B-domain or the Cac2 C terminus. J Biol Chem 2008; 283:14022-31. [PMID: 18334479 DOI: 10.1074/jbc.m800594200] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The assembly of core histones onto eukaryotic DNA is modulated by several histone chaperone complexes, including Asf1, CAF-1, and HIRA. Asf1 is a unique histone chaperone that participates in both the replication-dependent and replication-independent pathways. Here we report the crystal structures of the apo-form of fission yeast Asf1/Cia1 (SpAsf1N; residues 1-161) as well as its complexes with the B-domain of the fission yeast HIRA orthologue Hip1 (Hip1B) and the C-terminal region of the Cac2 subunit of CAF-1 (Cac2C). The mode of the fission yeast Asf1N-Hip1B recognition is similar to that of the human Asf1-HIRA recognition, suggesting that Asf1N recognition of Hip1B/HIRA is conserved from yeast to mammals. Interestingly, Hip1B and Cac2C show remarkably similar interaction modes with Asf1. The binding between Asf1N and Hip1B was almost completely abolished by the D37A and L60A/V62A mutations in Asf1N, indicating the critical role of salt bridge and van der Waals contacts in the complex formation. Consistently, both of the aforementioned Asf1 mutations also drastically reduced the binding to Cac2C. These results provide a structural basis for a mutually exclusive Asf1-binding model of CAF-1 and HIRA/Hip1, in which Asf1 and CAF-1 assemble histones H3/H4 (H3.1/H4 in vertebrates) in a replication-dependent pathway, whereas Asf1 and HIRA/Hip1 assemble histones H3/H4 (H3.3/H4 in vertebrates) in a replication-independent pathway.
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Affiliation(s)
- Ali D Malay
- Yokohama Institute, RIKEN, Tsurumi, Yokohama 230-0045, Japan
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25
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De Koning L, Corpet A, Haber JE, Almouzni G. Histone chaperones: an escort network regulating histone traffic. Nat Struct Mol Biol 2007; 14:997-1007. [PMID: 17984962 DOI: 10.1038/nsmb1318] [Citation(s) in RCA: 254] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
In eukaryotes, DNA is organized into chromatin in a dynamic manner that enables it to be accessed for processes such as transcription and repair. Histones, the chief protein component of chromatin, must be assembled, replaced or exchanged to preserve or change this organization according to cellular needs. Histone chaperones are key actors during histone metabolism. Here we classify known histone chaperones and discuss how they build a network to escort histone proteins. Molecular interactions with histones and their potential specificity or redundancy are also discussed in light of chaperone structural properties. The multiplicity of histone chaperone partners, including histone modifiers, nucleosome remodelers and cell-cycle regulators, is relevant to their coordination with key cellular processes. Given the current interest in chromatin as a source of epigenetic marks, we address the potential contributions of histone chaperones to epigenetic memory and genome stability.
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Affiliation(s)
- Leanne De Koning
- Laboratory of Nuclear Dynamics and Genome Plasticity (UMR 218), Institut Curie, 26 rue d'Ulm, 75248 Paris, France
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26
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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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27
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Blackwell JS, Wilkinson ST, Mosammaparast N, Pemberton LF. Mutational analysis of H3 and H4 N termini reveals distinct roles in nuclear import. J Biol Chem 2007; 282:20142-50. [PMID: 17507373 DOI: 10.1074/jbc.m701989200] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Core histones H3 and H4 are rapidly imported into the nucleus by members of the karyopherin (Kap)/importin family. We showed that H3 and H4 interact with Kap123p, histone acetyltransferase-B complex (HAT-B), and Asf1p in cytosol. In vivo analysis indicated that Kap123p is required for H3-mediated import, whereas H4 utilizes multiple Kaps including Kap123p. The evolutionary conservation of H3 and H4 cytoplasmic acetylation led us to analyze the role of acetylation in nuclear transport. We determined that lysine 14 is critical for H3 NLS function in vivo and demonstrated that mutation of H3 lysine 14 to the acetylation-mimic glutamine decreased association with Kap123p in vitro. Several lysines in the H4 NLS are important for its function. We showed that mutation of key lysines to glutamine resulted in a greater import defect than mutation to arginine, suggesting that positive charge promotes NLS function. Lastly we determined that six of ten N-terminal acetylation sites in H3 and H4 can be mutated to arginine, indicating that deposition acetylation is not absolutely necessary in vivo. However, the growth defect of these mutants suggests that acetylation does play an important role in import. These findings suggest a model where cytosolic histones bind import karyopherins prior to acetylation. Other factors are recruited to this complex such as HAT-B and Asf1p; these factors in turn promote acetylation. Acetylation may be important for modulating the interaction with transport factors and may play a role in the release of histones from karyopherins in the nucleus.
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Affiliation(s)
- Jeffrey S Blackwell
- Center for Cell Signaling, Department of Microbiology, University of Virginia Health Sciences Center, University of Virginia, Charlottesville, VA 22908, USA
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28
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Xhemalce B, Miller KM, Driscoll R, Masumoto H, Jackson SP, Kouzarides T, Verreault A, Arcangioli B. Regulation of Histone H3 Lysine 56 Acetylation in Schizosaccharomyces pombe. J Biol Chem 2007; 282:15040-7. [PMID: 17369611 DOI: 10.1074/jbc.m701197200] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
In Saccharomyces cerevisiae, acetylation of lysine 56 (Lys-56) in the globular domain of histone H3 plays an important role in response to genotoxic agents that interfere with DNA replication. However, the regulation and biological function of this modification are poorly defined in other eukaryotes. Here we show that Lys-56 acetylation in Schizosaccharomyces pombe occurs transiently during passage through S-phase and is normally removed in G(2). Genotoxic agents that cause DNA double strand breaks during replication elicit a delay in deacetylation of histone H3 Lys-56. In addition, mutant cells that cannot acetylate Lys-56 are acutely sensitive to genotoxic agents that block DNA replication. Moreover, we show that Spbc342.06cp, a previously uncharacterized open reading frame, encodes the functional homolog of S. cerevisiae Rtt109, and that this protein acetylates H3 Lys-56 both in vitro and in vivo. Altogether, our results indicate that both the regulation of histone H3 Lys-56 acetylation by its histone acetyltransferase and histone deacetylase and its role in the DNA damage response are conserved among two distantly related yeast model organisms.
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Affiliation(s)
- Blerta Xhemalce
- Unité de la Dynamique du Génome, Institut Pasteur, 25 rue du Dr. Roux, 75724, Paris Cedex 15, France.
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29
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Agez M, Chen J, Guerois R, van Heijenoort C, Thuret JY, Mann C, Ochsenbein F. Structure of the histone chaperone ASF1 bound to the histone H3 C-terminal helix and functional insights. Structure 2007; 15:191-9. [PMID: 17292837 DOI: 10.1016/j.str.2007.01.002] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2006] [Revised: 12/29/2006] [Accepted: 01/07/2007] [Indexed: 12/01/2022]
Abstract
Asf1 is a histone chaperone that favors histone H3/H4 assembly and disassembly. We solved the structure of the conserved domain of human ASF1A in complex with the C-terminal helix of histone H3 using nuclear magnetic resonance spectroscopy. This structure is fully compatible with an association of ASF1 with the heterodimeric form of histones H3/H4. In our model, ASF1 substitutes for the second H3/H4 heterodimer that is normally found in heterotetrameric H3/H4 complexes. This result constitutes an essential step in the fundamental understanding of the mechanisms of nucleosome assembly by histone chaperones. Point mutations that perturb the Asf1/histone interface were designed from the structure. The decreased binding affinity of the Asf1-H3/H4 complex correlates with decreased levels of H3-K56 acetylation and phenotypic defects in vivo.
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Affiliation(s)
- Morgane Agez
- Institut de Biologie et de Technologie de Saclay, Commissariat à l'Energie Atomique/Saclay, F-91191 Gif-sur-Yvette Cedex, France
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30
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Muto S, Senda M, Akai Y, Sato L, Suzuki T, Nagai R, Senda T, Horikoshi M. Relationship between the structure of SET/TAF-Ibeta/INHAT and its histone chaperone activity. Proc Natl Acad Sci U S A 2007; 104:4285-90. [PMID: 17360516 PMCID: PMC1810507 DOI: 10.1073/pnas.0603762104] [Citation(s) in RCA: 125] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2006] [Indexed: 11/18/2022] Open
Abstract
Histone chaperones assemble and disassemble nucleosomes in an ATP-independent manner and thus regulate the most fundamental step in the alteration of chromatin structure. The molecular mechanisms underlying histone chaperone activity remain unclear. To gain insights into these mechanisms, we solved the crystal structure of the functional domain of SET/TAF-Ibeta/INHAT at a resolution of 2.3 A. We found that SET/TAF-Ibeta/INHAT formed a dimer that assumed a "headphone"-like structure. Each subunit of the SET/TAF-Ibeta/INHAT dimer consisted of an N terminus, a backbone helix, and an "earmuff" domain. It resembles the structure of the related protein NAP-1. Comparison of the crystal structures of SET/TAF-Ibeta/INHAT and NAP-1 revealed that the two proteins were folded similarly except for an inserted helix. However, their backbone helices were shaped differently, and the relative dispositions of the backbone helix and the earmuff domain between the two proteins differed by approximately 40 degrees . Our biochemical analyses of mutants revealed that the region of SET/TAF-Ibeta/INHAT that is engaged in histone chaperone activity is the bottom surface of the earmuff domain, because this surface bound both core histones and double-stranded DNA. This overlap or closeness of the activity surface and the binding surfaces suggests that the specific association among SET/TAF-Ibeta/INHAT, core histones, and double-stranded DNA is requisite for histone chaperone activity. These findings provide insights into the possible mechanisms by which histone chaperones assemble and disassemble nucleosome structures.
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Affiliation(s)
- Shinsuke Muto
- *Laboratory of Developmental Biology, Institute of Molecular and Cellular Biosciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan
- Horikoshi Gene Selector Project, Exploratory Research for Advanced Technology, Japan Science and Technology Agency, 5-9-6 Tokodai, Tsukuba, Ibaraki 300-2635, Japan
- Departments of Cardiovascular Medicine and
| | - Miki Senda
- Japan Biological Information Research Center, Japan Biological Informatics Consortium, 2-42 Aomi, Koto-ku, Tokyo 135-0064, Japan; and
| | - Yusuke Akai
- Japan Biological Information Research Center, Japan Biological Informatics Consortium, 2-42 Aomi, Koto-ku, Tokyo 135-0064, Japan; and
| | - Lui Sato
- *Laboratory of Developmental Biology, Institute of Molecular and Cellular Biosciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan
| | - Toru Suzuki
- Departments of Cardiovascular Medicine and
- Clinical Bioinformatics, Graduate School of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan
| | | | - Toshiya Senda
- Biological Information Research Center, National Institute of Advanced Industrial Science and Technology, 2-42 Aomi, Koto-ku, Tokyo 135-0064, Japan
| | - Masami Horikoshi
- *Laboratory of Developmental Biology, Institute of Molecular and Cellular Biosciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan
- Horikoshi Gene Selector Project, Exploratory Research for Advanced Technology, Japan Science and Technology Agency, 5-9-6 Tokodai, Tsukuba, Ibaraki 300-2635, Japan
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Natsume R, Eitoku M, Akai Y, Sano N, Horikoshi M, Senda T. Structure and function of the histone chaperone CIA/ASF1 complexed with histones H3 and H4. Nature 2007; 446:338-41. [PMID: 17293877 DOI: 10.1038/nature05613] [Citation(s) in RCA: 240] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2006] [Accepted: 01/17/2007] [Indexed: 11/09/2022]
Abstract
CIA (CCG1-interacting factor A)/ASF1, which is the most conserved histone chaperone among the eukaryotes, was genetically identified as a factor for an anti-silencing function (Asf1) by yeast genetic screening. Shortly after that, the CIA-histone-H3-H4 complex was isolated from Drosophila as a histone chaperone CAF-1 stimulator. Human CIA-I/II (ASF1a/b) was identified as a histone chaperone that interacts with the bromodomain-an acetylated-histone-recognizing domain-of CCG1, in the general transcription initiation factor TFIID. Intensive studies have revealed that CIA/ASF1 mediates nucleosome assembly by forming a complex with another histone chaperone in human cells and yeast, and is involved in DNA replication, transcription, DNA repair and silencing/anti-silencing in yeast. CIA/ASF1 was shown as a major storage chaperone for soluble histones in proliferating human cells. Despite all these biochemical and biological functional analyses, the structure-function relationship of the nucleosome assembly/disassembly activity of CIA/ASF1 has remained elusive. Here we report the crystal structure, at 2.7 A resolution, of CIA-I in complex with histones H3 and H4. The structure shows the histone H3-H4 dimer's mutually exclusive interactions with another histone H3-H4 dimer and CIA-I. The carboxy-terminal beta-strand of histone H4 changes its partner from the beta-strand in histone H2A to that of CIA-I through large conformational change. In vitro functional analysis demonstrated that CIA-I has a histone H3-H4 tetramer-disrupting activity. Mutants with weak histone H3-H4 dimer binding activity showed critical functional effects on cellular processes related to transcription. The histone H3-H4 tetramer-disrupting activity of CIA/ASF1 and the crystal structure of the CIA/ASF1-histone-H3-H4 dimer complex should give insights into mechanisms of both nucleosome assembly/disassembly and nucleosome semi-conservative replication.
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Affiliation(s)
- Ryo Natsume
- Japan Biological Information Research Centre (JBIRC), Japan Biological Informatics Consortium (JBIC), 2-42 Aomi, Koto-ku, Tokyo 135-0064, Japan
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Mongelard F, Bouvet P. Nucleolin: a multiFACeTed protein. Trends Cell Biol 2007; 17:80-6. [PMID: 17157503 DOI: 10.1016/j.tcb.2006.11.010] [Citation(s) in RCA: 247] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2006] [Accepted: 11/30/2006] [Indexed: 11/28/2022]
Abstract
Nucleolin is an abundant, ubiquitously expressed protein that is found in various cell compartments, especially in the nucleolus, of which it is a major component. This multifunctional protein has been described as being a part of many pathways, from interactions with viruses at the cellular membrane to essential processing of the ribosomal RNA in the nucleolus. However, most of the molecular details of these different functions are not understood. Here, we focus on the role of nucleolin in transcription, especially some recent findings describing the protein as a histone chaperone [with functional similarity to the facilitates chromatin transcription (FACT) complex] and a chromatin co-remodeler. These new properties could help reconcile discrepancies in the literature regarding the role of nucleolin in transcription.
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Affiliation(s)
- Fabien Mongelard
- Laboratoire Joliot-Curie, Ecole Normale Supérieure de Lyon, 46 Allée d'Italie, 69007 Lyon, France
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33
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Mousson F, Ochsenbein F, Mann C. The histone chaperone Asf1 at the crossroads of chromatin and DNA checkpoint pathways. Chromosoma 2006; 116:79-93. [PMID: 17180700 DOI: 10.1007/s00412-006-0087-z] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2006] [Revised: 10/11/2006] [Accepted: 10/13/2006] [Indexed: 10/23/2022]
Abstract
Nucleosome assembly involves deposition of a heterotetramer of histones H3/H4 onto DNA followed by two heterodimers of histones H2A/H2B. Cycles of nucleosome assembly and disassembly are essential to cellular events such as replication, transcription, and DNA repair. After synthesis in the cytoplasm, histones are shuttled into the nucleus where they are associated with chaperone proteins. Chaperones of histones H3/H4 include CAF-I, the Hir proteins, and Asf1. CAF-I and the Hir proteins function as replication-coupled and replication-independent deposition factors for H3/H4, respectively, whereas Asf1 may play a role in both pathways. In addition to acting as assembly factors, histone chaperones assist nucleosome dissociation from DNA and they may recruit other proteins to chromatin. The past few years have witnessed a notable accumulation of genetic, biochemical, and structural data on Asf1, which motivated this review. We discuss the sequence and structural features of Asf1 before considering its roles in nucleosome assembly/disassembly, the cellular response to DNA damage, and the regulation of gene expression. We emphasize the key role of Asf1 as a central node in a network of partners that place it at the crossroads of chromatin and DNA checkpoint pathways.
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Affiliation(s)
- Florence Mousson
- Département de Biologie Joliot-Curie, Service de Biophysique des Fonctions Membranaires, CEA/Saclay, 91191 Gif-sur-Yvette, France
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Structure of the yeast histone H3-ASF1 interaction: implications for chaperone mechanism, species-specific interactions, and epigenetics. BMC STRUCTURAL BIOLOGY 2006; 6:26. [PMID: 17166288 PMCID: PMC1762009 DOI: 10.1186/1472-6807-6-26] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/17/2006] [Accepted: 12/13/2006] [Indexed: 11/10/2022]
Abstract
Background The histone H3/H4 chaperone Asf1 (anti-silencing function 1) is required for the establishment and maintenance of proper chromatin structure, as well as for genome stability in eukaryotes. Asf1 participates in both DNA replication-coupled (RC) and replication-independent (RI) histone deposition reactions in vitro and interacts with complexes responsible for both pathways in vivo. Asf1 is known to directly bind histone H3, however, high-resolution structural information about the geometry of this interaction was previously unknown. Results Here we report the structure of a histone/histone chaperone interaction. We have solved the 2.2 Å crystal structure of the conserved N-terminal immunoglobulin fold domain of yeast Asf1 (residues 2–155) bound to the C-terminal helix of yeast histone H3 (residues 121–134). The structure defines a histone-binding patch on Asf1 consisting of both conserved and yeast-specific residues; mutation of these residues abrogates H3/H4 binding affinity. The geometry of the interaction indicates that Asf1 binds to histones H3/H4 in a manner that likely blocks sterically the H3/H3 interface of the nucleosomal four-helix bundle. Conclusion These data clarify how Asf1 regulates histone stoichiometry to modulate epigenetic inheritance. The structure further suggests a physical model in which Asf1 contributes to interpretation of a "histone H3 barcode" for sorting H3 isoforms into different deposition pathways.
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Recht J, Tsubota T, Tanny JC, Diaz RL, Berger JM, Zhang X, Garcia BA, Shabanowitz J, Burlingame AL, Hunt DF, Kaufman PD, Allis CD. Histone chaperone Asf1 is required for histone H3 lysine 56 acetylation, a modification associated with S phase in mitosis and meiosis. Proc Natl Acad Sci U S A 2006; 103:6988-93. [PMID: 16627621 PMCID: PMC1459006 DOI: 10.1073/pnas.0601676103] [Citation(s) in RCA: 198] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Histone acetylation affects many nuclear processes including transcription, chromatin assembly, and DNA damage repair. Acetylation of histone H3 lysine 56 (H3 K56ac) in budding yeast occurs during mitotic S phase and persists during DNA damage repair. Here, we show that H3 K56ac is also present during premeiotic S phase and is conserved in fission yeast. Furthermore, the H3 K56ac modification is not observed in the absence of the histone chaperone Asf1. asf1delta and H3 K56R mutants exhibit similar sensitivity to DNA damaging agents. Mutational analysis of Asf1 demonstrates that DNA damage sensitivity correlates with (i) decreased levels of H3 K56ac and (ii) a region implicated in histone binding. In contrast, multiple asf1 mutants that are resistant to DNA damage display WT levels of K56ac. These data suggest that maintenance of H3 K56 acetylation is a primary contribution of Asf1 to genome stability in yeast.
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Affiliation(s)
- J. Recht
- *Laboratory of Chromatin Biology, The Rockefeller University, New York, NY 10021
| | - T. Tsubota
- Program in Gene Function and Expression, University of Massachusetts Medical School, Worcester, MA 01605
| | - J. C. Tanny
- *Laboratory of Chromatin Biology, The Rockefeller University, New York, NY 10021
| | - R. L. Diaz
- *Laboratory of Chromatin Biology, The Rockefeller University, New York, NY 10021
| | - J. M. Berger
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720
| | - X. Zhang
- Department of Pharmaceutical Chemistry and Mass Spectrometry Facility, University of California, San Francisco, CA 94143; and
| | - B. A. Garcia
- Department of Chemistry, University of Virginia, Charlottesville, VA 22901
| | - J. Shabanowitz
- Department of Chemistry, University of Virginia, Charlottesville, VA 22901
| | - A. L. Burlingame
- Department of Pharmaceutical Chemistry and Mass Spectrometry Facility, University of California, San Francisco, CA 94143; and
| | - D. F. Hunt
- Department of Chemistry, University of Virginia, Charlottesville, VA 22901
| | - P. D. Kaufman
- Program in Gene Function and Expression, University of Massachusetts Medical School, Worcester, MA 01605
| | - C. D. Allis
- *Laboratory of Chromatin Biology, The Rockefeller University, New York, NY 10021
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English CM, Maluf NK, Tripet B, Churchill MEA, Tyler JK. ASF1 binds to a heterodimer of histones H3 and H4: a two-step mechanism for the assembly of the H3-H4 heterotetramer on DNA. Biochemistry 2006; 44:13673-82. [PMID: 16229457 PMCID: PMC4445473 DOI: 10.1021/bi051333h] [Citation(s) in RCA: 108] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The first step in the formation of the nucleosome is commonly assumed to be the deposition of a histone H3-H4 heterotetramer onto DNA. Antisilencing function 1 (ASF1) is a major histone H3-H4 chaperone that deposits histones H3 and H4 onto DNA. With a goal of understanding the mechanism of deposition of histones H3 and H4 onto DNA, we have determined the stoichiometry of the Asf1-H3-H4 complex. We have established that a single molecule of Asf1 binds to an H3-H4 heterodimer using gel filtration, amino acid, reversed-phase chromatography, and analytical ultracentrifugation analyses. We demonstrate that Asf1 blocks formation of the H3-H4 heterotetramer by a mechanism that likely involves occlusion of the H3-H3 dimerization interface.
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Affiliation(s)
- Christine M English
- Department of Biochemistry and Molecular Genetics, University of Colorado Health Sciences Center at Fitzsimons, Aurora, Colorado 80045, USA
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Tamburini BA, Carson JJ, Linger JG, Tyler JK. Dominant mutants of the Saccharomyces cerevisiae ASF1 histone chaperone bypass the need for CAF-1 in transcriptional silencing by altering histone and Sir protein recruitment. Genetics 2006; 173:599-610. [PMID: 16582440 PMCID: PMC1526541 DOI: 10.1534/genetics.105.054783] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Transcriptional silencing involves the formation of specialized repressive chromatin structures. Previous studies have shown that the histone H3-H4 chaperone known as chromatin assembly factor 1 (CAF-1) contributes to transcriptional silencing in yeast, although the molecular basis for this was unknown. In this work we have identified mutations in the nonconserved C terminus of antisilencing function 1 (Asf1) that result in enhanced silencing of HMR and telomere-proximal reporters, overcoming the requirement for CAF-1 in transcriptional silencing. We show that CAF-1 mutants have a drastic reduction in DNA-bound histone H3 levels, resulting in reduced recruitment of Sir2 and Sir4 to the silent loci. C-terminal mutants of another histone H3-H4 chaperone Asf1 restore the H3 levels and Sir protein recruitment to the silent loci in CAF-1 mutants, probably as a consequence of the weakened interaction between these Asf1 mutants and histone H3. As such, these studies have identified the nature of the molecular defect in the silent chromatin structure that results from inactivation of the histone chaperone CAF-1.
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Affiliation(s)
- Beth A Tamburini
- Department of Biology Graduate Program, University of Colorado Health Sciences Center, Aurora, Colorado 80045, USA
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38
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Jin C, Kato K, Chimura T, Yamasaki T, Nakade K, Murata T, Li H, Pan J, Zhao M, Sun K, Chiu R, Ito T, Nagata K, Horikoshi M, Yokoyama KK. Regulation of histone acetylation and nucleosome assembly by transcription factor JDP2. Nat Struct Mol Biol 2006; 13:331-8. [PMID: 16518400 DOI: 10.1038/nsmb1063] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2005] [Accepted: 01/17/2006] [Indexed: 01/08/2023]
Abstract
Jun dimerization protein-2 (JDP2) is a component of the AP-1 transcription factor that represses transactivation mediated by the Jun family of proteins. Here, we examine the functional mechanisms of JDP2 and show that it can inhibit p300-mediated acetylation of core histones in vitro and in vivo. Inhibition of histone acetylation requires the N-terminal 35 residues and the DNA-binding region of JDP2. In addition, we demonstrate that JDP2 has histone-chaperone activity in vitro. These results suggest that the sequence-specific DNA-binding protein JDP2 may control transcription via direct regulation of the modification of histones and the assembly of chromatin.
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Affiliation(s)
- Chunyuan Jin
- Gene Engineering Division, Dept. of Biological Systems, BioResource Center, RIKEN (The Institute of Physical & Chemical Research), Tsukuba Science City, Ibaraki 305-0074, Japan
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Tamburini BA, Carson JJ, Adkins MW, Tyler JK. Functional conservation and specialization among eukaryotic anti-silencing function 1 histone chaperones. EUKARYOTIC CELL 2005; 4:1583-90. [PMID: 16151251 PMCID: PMC1214205 DOI: 10.1128/ec.4.9.1583-1590.2005] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Chromatin disassembly and reassembly, mediated by histone chaperones such as anti-silencing function 1 (Asf1), are likely to accompany all nuclear processes that occur on the DNA template. In order to gain insight into the functional conservation of Asf1 across eukaryotes, we have replaced the budding yeast Asf1 protein with Drosophila Asf1 (dAsf1) or either of the two human Asf1 (hAsf1a and hAsf1b) counterparts. We found that hAsf1b is best able to rescue the growth defect of Saccharomyces cerevisiae lacking Asf1. Moreover, dAsf1 and hAsf1b but not hAsf1a can replace the role of yeast Asf1 in protecting against replicational stress and activating the PHO5 gene, while only hAsf1a can replace the role of Asf1 in protecting against double-stranded-DNA-damaging agents. Furthermore, it appears that the interaction between Asf1 and the DNA damage checkpoint protein Rad53 is not required for Asf1's role in maintaining genomic integrity. In addition to indicating the functional conservation of the Asf1 proteins across species, these studies suggest distinct roles for the two human Asf1 proteins.
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Affiliation(s)
- Beth A Tamburini
- Department of Biochemistry and Molecular Genetics, University of Colorado Health Sciences Center, Aurora, Colorado 80010, USA
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Umehara T, Otta Y, Tsuganezawa K, Matsumoto T, Tanaka A, Horikoshi M, Padmanabhan B, Yokoyama S. Purification, crystallization and preliminary X-ray diffraction analysis of the histone chaperone cia1 from fission yeast. Acta Crystallogr Sect F Struct Biol Cryst Commun 2005; 61:971-3. [PMID: 16511210 PMCID: PMC1978123 DOI: 10.1107/s1744309105030927] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2005] [Accepted: 09/27/2005] [Indexed: 11/10/2022]
Abstract
In fission yeast, cia1+ is an essential gene that encodes a histone chaperone, a homologue of human CIA (CCG1-interacting factor A) and budding yeast Asf1p (anti-silencing function-1), which both facilitate nucleosome assembly by interacting with the core histones H3/H4. The conserved domain (residues 1-161) of the cia1+-encoded protein was expressed in Escherichia coli, purified to near-homogeneity and crystallized by the sitting-drop vapour-diffusion method. The protein was crystallized in the monoclinic space group C2, with unit-cell parameters a = 79.16, b = 40.53, c = 69.79 A, beta = 115.93 degrees and one molecule per asymmetric unit. The crystal diffracted to beyond 2.10 A resolution using synchrotron radiation.
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Affiliation(s)
- Takashi Umehara
- RIKEN Genomic Sciences Center, 1-7-22 Suehiro, Tsurumi, Yokohama 230-0045, Japan
| | - Yumi Otta
- RIKEN Genomic Sciences Center, 1-7-22 Suehiro, Tsurumi, Yokohama 230-0045, Japan
| | - Keiko Tsuganezawa
- RIKEN Genomic Sciences Center, 1-7-22 Suehiro, Tsurumi, Yokohama 230-0045, Japan
| | - Takehisa Matsumoto
- RIKEN Genomic Sciences Center, 1-7-22 Suehiro, Tsurumi, Yokohama 230-0045, Japan
| | - Akiko Tanaka
- RIKEN Genomic Sciences Center, 1-7-22 Suehiro, Tsurumi, Yokohama 230-0045, Japan
| | - Masami Horikoshi
- Laboratory of Developmental Biology, Institute of Molecular and Cellular Biosciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 111-0032, Japan
- Horikoshi Gene Selector Project, Exploratory Research for Advanced Technology (ERATO), Japan Science and Technology Corporation (JST), 5-9-6 Tokodai, Tsukuba, Ibaraki 300-2635, Japan
| | - Balasundaram Padmanabhan
- RIKEN Genomic Sciences Center, 1-7-22 Suehiro, Tsurumi, Yokohama 230-0045, Japan
- Correspondence e-mail: ,
| | - Shigeyuki Yokoyama
- RIKEN Genomic Sciences Center, 1-7-22 Suehiro, Tsurumi, Yokohama 230-0045, Japan
- RIKEN Harima Institute at SPring-8, 1-1-1 Kouto, Mikazuki-cho, Sayo, Hyogo 679-5148, Japan
- Department of Biophysics and Biochemistry, Graduate School of Science, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
- Correspondence e-mail: ,
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Swaminathan V, Kishore AH, Febitha KK, Kundu TK. Human histone chaperone nucleophosmin enhances acetylation-dependent chromatin transcription. Mol Cell Biol 2005; 25:7534-45. [PMID: 16107701 PMCID: PMC1190275 DOI: 10.1128/mcb.25.17.7534-7545.2005] [Citation(s) in RCA: 137] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Histone chaperones are a group of proteins that aid in the dynamic chromatin organization during different cellular processes. Here, we report that the human histone chaperone nucleophosmin interacts with the core histones H3, H2B, and H4 but that this histone interaction is not sufficient to confer the chaperone activity. Significantly, nucleophosmin enhances the acetylation-dependent chromatin transcription and it becomes acetylated both in vitro and in vivo. Acetylation of nucleophosmin and the core histones was found to be essential for the enhancement of chromatin transcription. The acetylated NPM1 not only shows an increased affinity toward acetylated histones but also shows enhanced histone transfer ability. Presumably, nucleophosmin disrupts the nucleosomal structure in an acetylation-dependent manner, resulting in the transcriptional activation. These results establish nucleophosmin (NPM1) as a human histone chaperone that becomes acetylated, resulting in the enhancement of chromatin transcription.
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Affiliation(s)
- V Swaminathan
- Transcription and Disease Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Center for Advanced Scientific Research, Jakkur, Bangalore, India
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42
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Mousson F, Lautrette A, Thuret JY, Agez M, Courbeyrette R, Amigues B, Becker E, Neumann JM, Guerois R, Mann C, Ochsenbein F. Structural basis for the interaction of Asf1 with histone H3 and its functional implications. Proc Natl Acad Sci U S A 2005; 102:5975-80. [PMID: 15840725 PMCID: PMC1087920 DOI: 10.1073/pnas.0500149102] [Citation(s) in RCA: 108] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Asf1 is a conserved histone chaperone implicated in nucleosome assembly, transcriptional silencing, and the cellular response to DNA damage. We solved the NMR solution structure of the N-terminal functional domain of the human Asf1a isoform, and we identified by NMR chemical shift mapping a surface of Asf1a that binds the C-terminal helix of histone H3. This binding surface forms a highly conserved hydrophobic groove surrounded by charged residues. Mutations within this binding site decreased the affinity of Asf1a for the histone H3/H4 complex in vitro, and the same mutations in the homologous yeast protein led to transcriptional silencing defects, DNA damage sensitivity, and thermosensitive growth. We have thus obtained direct experimental evidence of the mode of binding between a histone and one of its chaperones and genetic data suggesting that this interaction is important in both the DNA damage response and transcriptional silencing.
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Affiliation(s)
- Florence Mousson
- Service de Biophysique des Fonctions Membranaires and Service de Biochimie et de Génétique Moléculaire, Département de Biologie Joliot-Curie, Commissariat à l'Energie Atomique (CEA/Saclay), F-91191 Gif-sur-Yvette, France
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Prado A, Ramos I, Frehlick LJ, Muga A, Ausió J. Nucleoplasmin: a nuclear chaperone. Biochem Cell Biol 2005; 82:437-45. [PMID: 15284896 DOI: 10.1139/o04-042] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In this article, we briefly review the structural and functional information currently available on nucleoplasmin. Special emphasis is placed on the discussion of the molecular mechanism involved in the sperm chromatin remodelling activity of this protein. A model is proposed based on current crystallographic data, recent biophysical and functional studies, as well as in the previously available information.
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44
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Adkins MW, Tyler JK. The histone chaperone Asf1p mediates global chromatin disassembly in vivo. J Biol Chem 2004; 279:52069-74. [PMID: 15452122 DOI: 10.1074/jbc.m406113200] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The packaging of the eukaryotic genome into chromatin is likely to be mediated by chromatin assembly factors, including histone chaperones. We investigated the function of the histone H3/H4 chaperones anti-silencing function 1 (Asf1p) and chromatin assembly factor 1 (CAF-1) in vivo. Analysis of chromatin structure by accessibility to micrococcal nuclease and DNase I digestion demonstrated that the chromatin from CAF-1 mutant yeast has increased accessibility to these enzymes. In agreement, the supercoiling of the endogenous 2mu plasmid is reduced in yeast lacking CAF-1. These results indicate that CAF-1 mutant yeast globally under-assemble their genome into chromatin, consistent with a role for CAF-1 in chromatin assembly in vivo. By contrast, asf1 mutants globally over-assemble their genome into chromatin, as suggested by decreased accessibility of their chromatin to micrococcal nuclease and DNase I digestion and increased supercoiling of the endogenous 2mu plasmid. Deletion of ASF1 causes a striking loss of acetylation on histone H3 lysine 9, but this is not responsible for the altered chromatin structure in asf1 mutants. These data indicate that Asf1p may have a global role in chromatin disassembly and an unexpected role in histone acetylation in vivo.
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Affiliation(s)
- Melissa W Adkins
- Department of Biochemistry and Molecular Genetics, University of Colorado Health Sciences Center at Fitzsimons, Aurora, Colorado 80045, USA
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45
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Koundrioukoff S, Polo S, Almouzni G. Interplay between chromatin and cell cycle checkpoints in the context of ATR/ATM-dependent checkpoints. DNA Repair (Amst) 2004; 3:969-78. [PMID: 15279783 DOI: 10.1016/j.dnarep.2004.03.010] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Maintenance of both genome stability and its structural organization into chromatin are essential to avoid aberrant gene expression that could lead to neoplasia. Genome integrity being threatened by various sources of genotoxic stresses, cells have evolved regulatory mechanisms, termed cell cycle checkpoints. In general, these surveillance pathways are thought to act mainly to coordinate proficient DNA repair with cell cycle progression. To date, this cellular response to genotoxic stress has been viewed mainly as a DNA-based signal transduction pathway. Recent studies, in both yeast and human, however, highlight possible connections between chromatin structure and cell cycle checkpoints, in particular those involving kinases of the ATM and ATR family, known as key response factors activated early in the checkpoint pathway. In this review, based on this example, we will discuss hypotheses for chromatin-based events as potential initiators of a checkpoint response or conversely, for chromatin-associated factors as targets of checkpoint proteins, promoting changes in chromatin structure, in order to make a lesion more accessible and contribute to a more efficient repair response.
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Affiliation(s)
- Stephane Koundrioukoff
- Laboratory of Nuclear Dynamics and Genome Plasticity, UMR 218 CNRS/Curie Institute, 26 rue d'Ulm, 75248 Paris, cedex 5, France
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Daganzo SM, Erzberger JP, Lam WM, Skordalakes E, Zhang R, Franco AA, Brill SJ, Adams PD, Berger JM, Kaufman PD. Structure and function of the conserved core of histone deposition protein Asf1. Curr Biol 2004; 13:2148-58. [PMID: 14680630 DOI: 10.1016/j.cub.2003.11.027] [Citation(s) in RCA: 118] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
BACKGROUND Asf1 is a ubiquitous eukaryotic histone binding and deposition protein that mediates nucleosome formation in vitro and is required for genome stability in vivo. Studies in a variety of organisms have defined Asf1's role as a histone chaperone during DNA replication through specific interactions with histones H3/H4 and the histone deposition factor CAF-I. In addition to its role in replication, conserved interactions with proteins involved in chromatin silencing, transcription, chromatin remodeling, and DNA repair have also established Asf1 as an important component of a number of chromatin assembly and modulation complexes. RESULTS We demonstrate that the highly conserved N-terminal domain of S. cerevisiae Asf1 (Asf1N) is the core region that mediates all tested functions of the full-length protein. The crystal structure of this core domain, determined to 1.5 A resolution, reveals a compact immunoglobulin-like beta sandwich fold topped by three helical linkers. The surface of Asf1 displays a conserved hydrophobic groove flanked on one side by an area of strong electronegative surface potential. These regions represent potential binding sites for histones and other interacting proteins. The structural model also allowed us to interpret mutagenesis studies of the human Asf1a/HIRA interaction and to functionally define the region of Asf1 responsible for Hir1-dependent telomeric silencing in budding yeast. CONCLUSIONS The evolutionarily conserved, N-terminal 155 amino acids of histone deposition protein Asf1 are functional in vitro and in vivo. This core region of Asf1 adopts a compact immunoglobulin-fold structure with distinct surface characteristics, including a Hir protein binding region required for gene silencing.
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Affiliation(s)
- Sally M Daganzo
- Lawrence Berkeley National Laboratory, University of California-Berkeley, Berkeley, CA 94720, USA
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Kuzuhara T, Horikoshi M. A nuclear FK506-binding protein is a histone chaperone regulating rDNA silencing. Nat Struct Mol Biol 2004; 11:275-83. [PMID: 14981505 DOI: 10.1038/nsmb733] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2003] [Accepted: 01/23/2004] [Indexed: 01/16/2023]
Abstract
We report a novel chromatin-modulating factor, nuclear FK506-binding protein (FKBP). It is a member of the peptidyl prolyl cis-trans isomerase (PPIase) family, whose members were originally identified as enzymes that assist in the proper folding of polypeptides. The endogenous FKBP gene is required for the in vivo silencing of gene expression at the rDNA locus and FKBP has histone chaperone activity in vitro. Both of these properties depend on the N-terminal non-PPIase domain of the protein. The C-terminal PPIase domain is not essential for the histone chaperone activity in vitro, but it regulates rDNA silencing in vivo. Chromatin immunoprecipitation showed that nuclear FKBP associates with chromatin at rDNA loci in vivo. These in vivo and in vitro findings in nuclear FKBPs reveal a hitherto unsuspected link between PPIases and the alteration of chromatin structure.
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Affiliation(s)
- Takashi Kuzuhara
- Laboratory of Developmental Biology, Institute of Molecular and Cellular Biosciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-0032, Japan
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Padmanabhan B, Kuzuhara T, Adachi N, Horikoshi M. The crystal structure of CCG1/TAF(II)250-interacting factor B (CIB). J Biol Chem 2003; 279:9615-24. [PMID: 14672934 DOI: 10.1074/jbc.m312165200] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The general transcription initiation factor TFIID and its interactors play critical roles in regulating the transcription from both naked and chromatin DNA. We have isolated a novel TFIID interactor that we denoted as CCG1/TAF(II)250-interacting factor B (CIB). We show here that CIB activates transcription. To further understand the function of this protein, we determined its crystal structure at 2.2-Angstroms resolution. The tertiary structure of CIB reveals an alpha/beta-hydrolase fold that resembles structures in the prokaryotic alpha/beta-hydrolase family proteins. It is not similar in structure or primary sequence to any eukaryotic transcription or chromatin factors that have been reported to date. CIB possesses a conserved catalytic triad that is found in other alpha/beta-hydrolases, and our in vitro studies confirmed that it bears hydrolase activity. However, CIB differs from other alpha/beta-hydrolases in that it lacks a binding site excursion, which facilitates the substrate selectivity of the other alpha/beta-hydrolases. Further functional characterization of CIB based on its tertiary structure and through biochemical studies may provide novel insights into the mechanisms that regulate eukaryotic transcription.
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Affiliation(s)
- Balasundaram Padmanabhan
- Horikoshi Gene Selector Project, Exploratory Research for Advanced Technology, Japan Science and Technology Corporation, 5-9-6 Tokodai, Tsukuba, Ibaraki 300-2635, Japan
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Carrera P, Moshkin YM, Gronke S, Sillje HHW, Nigg EA, Jackle H, Karch F. Tousled-like kinase functions with the chromatin assembly pathway regulating nuclear divisions. Genes Dev 2003; 17:2578-90. [PMID: 14561777 PMCID: PMC218151 DOI: 10.1101/gad.276703] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Tousled-like kinases (TLKs) constitute a family of serine/threonine kinases conserved in plants and animals that act in a cell cycle-dependent manner. In mammals, their activity peaks during S phase, when they phosphorylate the antisilencing function protein 1 (ASF1), a histone chaperone involved in replication-dependent chromatin assembly. Here, we show that Drosophila ASF1 is also a phosphorylation target of TLK, and that the two components cooperate to control chromatin replication in vivo. By altering TLK activity through loss-of-function mutations, we show that nuclear divisions are arrested at interphase, followed by apoptosis. Overexpression of TLK alters the chromatin structure, suggesting that TLK mediates the activity of chromatin proteins. These results suggest that TLK coordinates cell cycle progression through the regulation of chromatin dynamics.
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Affiliation(s)
- Pilar Carrera
- Abteilung Molekulare Entwicklungsbiologie, Max-Planck-Institut für biophysikalische Chemie, Am Fassberg, D-37077 Göttingen, Germany
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Umehara T, Horikoshi M. Transcription initiation factor IID-interactive histone chaperone CIA-II implicated in mammalian spermatogenesis. J Biol Chem 2003; 278:35660-7. [PMID: 12842904 DOI: 10.1074/jbc.m303549200] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Histones are thought to have specific roles in mammalian spermatogenesis, because several subtypes of histones emerge that are post-translationally modified during spermatogenesis. Though regular assembly of nucleosome is guaranteed by histone chaperones, their involvement in spermatogenesis is yet to be characterized. Here we identified a histone chaperone-related factor, which we designated as CCG1-interacting factor A-II (CIA-II), through interaction with bromodomains of TAFII250/CCG1, which is the largest subunit of human transcription initiation factor IID (TFIID). We found that human CIA-II (hCIA-II) localizes in HeLa nuclei and is highly expressed in testis and other proliferating cell-containing tissues. Expression of mouse CIA-II (mCIA-II) does not occur in the germ cell-lacking testes of adult WBB6F1-W/Wv mutant mice, indicating its expression in testis to be specific to germ cells. Fractionation of testicular germ cells revealed that mCIA-II transcripts accumulate in pachytene spermatocytes but not in spermatids. In addition, the mCIA-II transcripts in testis were present as early as 4 days after birth and decreased at 56 days after birth. These findings indicate that mCIA-II expression in testis is restricted to premeiotic to meiotic stages during spermatogenesis. Also, we found that hCIA-II interacts with histone H3 in vivo and with histones H3/H4 in vitro and that it facilitates supercoiling of circular DNA when it is incubated with core histones and topoisomerase I in vitro. These data suggest that CIA-II is a histone chaperone and is implicated in the regulation of mammalian spermatogenesis.
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Affiliation(s)
- Takashi Umehara
- Laboratory of Developmental Biology, Institute of Molecular and Cellular Biosciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan
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