1
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Shaban K, Dolson A, Fisher A, Lessard E, Sauty SM, Yankulov K. TOF1 and RRM3 reveal a link between gene silencing and the pausing of replication forks. Curr Genet 2023; 69:235-249. [PMID: 37347284 DOI: 10.1007/s00294-023-01273-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 06/01/2023] [Accepted: 06/14/2023] [Indexed: 06/23/2023]
Abstract
Eukaryotic DNA replication is accompanied by the disassembly and reassembly of nucleosomes and the transmission of epigenetic marks to the newly assembled chromatids. Several histone chaperones, including CAF-1 and Asf1p, are central to these processes. On the other hand, replication forks pause at numerous positions throughout the genome, but it is not known if and how this pausing affects the reassembly and maintenance of chromatin structures. Here, we applied drug-free gene silencing assays to analyze the genetic interactions between CAC1, ASF1, and two genes that regulate the stability of the paused replisome (TOF1) and the resumption of elongation (RRM3). Our results show that TOF1 and RRM3 differentially interact with CAF-1 and ASF1 and that the deletions of TOF1 and RRM3 lead to reduced silencing and increased frequency of epigenetic conversions at three loci in the genome of S. cerevisiae. Our study adds details to the known activities of CAF-1 and Asf1p and suggests that the pausing of the replication fork can lead to epigenetic instability.
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Affiliation(s)
- Kholoud Shaban
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, N1G2W1, Canada
| | - Andrew Dolson
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, N1G2W1, Canada
| | - Ashley Fisher
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, N1G2W1, Canada
| | - Emma Lessard
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, N1G2W1, Canada
| | - Safia Mahabub Sauty
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, N1G2W1, Canada
| | - Krassimir Yankulov
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, N1G2W1, Canada.
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2
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Cho C, Ganser C, Uchihashi T, Kato K, Song JJ. Structure of the human ATAD2 AAA+ histone chaperone reveals mechanism of regulation and inter-subunit communication. Commun Biol 2023; 6:993. [PMID: 37770645 PMCID: PMC10539301 DOI: 10.1038/s42003-023-05373-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Accepted: 09/19/2023] [Indexed: 09/30/2023] Open
Abstract
ATAD2 is a non-canonical ATP-dependent histone chaperone and a major cancer target. Despite widespread efforts to design drugs targeting the ATAD2 bromodomain, little is known about the overall structural organization and regulation of ATAD2. Here, we present the 3.1 Å cryo-EM structure of human ATAD2 in the ATP state, showing a shallow hexameric spiral that binds a peptide substrate at the central pore. The spiral conformation is locked by an N-terminal linker domain (LD) that wedges between the seam subunits, thus limiting ATP-dependent symmetry breaking of the AAA+ ring. In contrast, structures of the ATAD2-histone H3/H4 complex show the LD undocked from the seam, suggesting that H3/H4 binding unlocks the AAA+ spiral by allosterically releasing the LD. These findings, together with the discovery of an inter-subunit signaling mechanism, reveal a unique regulatory mechanism for ATAD2 and lay the foundation for developing new ATAD2 inhibitors.
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Affiliation(s)
- Carol Cho
- Department of Biological Sciences, KAIST Stem Cell Center, Basic Science 4.0 Institute, and KI for BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Korea.
| | - Christian Ganser
- Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji, Okazaki, Aichi, 444-8787, Japan
| | - Takayuki Uchihashi
- Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji, Okazaki, Aichi, 444-8787, Japan
- Department of Physics and Institute for Glyco-core Research (iGCORE), Nagoya University, Chikusa-ku, Furo-cho, Nagoya, Aichi, 464-8602, Japan
| | - Koichi Kato
- Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji, Okazaki, Aichi, 444-8787, Japan
- Graduate School of Pharmaceutical Sciences, Nagoya City University, 3-1 Tanabe-dori, Mizuho-ku, Nagoya, Aichi, 467-8603, Japan
- Institute for Molecular Science (IMS), National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji, Okazaki, Aichi, 444-8787, Japan
| | - Ji-Joon Song
- Department of Biological Sciences, KAIST Stem Cell Center, Basic Science 4.0 Institute, and KI for BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Korea.
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3
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Nikolov VN, Malavia D, Kubota T. SWI/SNF and the histone chaperone Rtt106 drive expression of the Pleiotropic Drug Resistance network genes. Nat Commun 2022; 13:1968. [PMID: 35413952 PMCID: PMC9005695 DOI: 10.1038/s41467-022-29591-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Accepted: 03/23/2022] [Indexed: 12/13/2022] Open
Abstract
The Pleiotropic Drug Resistance (PDR) network is central to the drug response in fungi, and its overactivation is associated with drug resistance. However, gene regulation of the PDR network is not well understood. Here, we show that the histone chaperone Rtt106 and the chromatin remodeller SWI/SNF control expression of the PDR network genes and confer drug resistance. In Saccharomyces cerevisiae, Rtt106 specifically localises to PDR network gene promoters dependent on transcription factor Pdr3, but not Pdr1, and is essential for Pdr3-mediated basal expression of the PDR network genes, while SWI/SNF is essential for both basal and drug-induced expression. Also in the pathogenic fungus Candida glabrata, Rtt106 and SWI/SNF regulate drug-induced PDR gene expression. Consistently, loss of Rtt106 or SWI/SNF sensitises drug-resistant S. cerevisiae mutants and C. glabrata to antifungal drugs. Since they cooperatively drive PDR network gene expression, Rtt106 and SWI/SNF represent potential therapeutic targets to combat antifungal resistance.
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Affiliation(s)
- Vladislav N Nikolov
- Institute of Medical Sciences, School of Medicine, Medical Sciences & Nutrition, University of Aberdeen, Foresterhill, Aberdeen, AB25 2ZD, UK
| | - Dhara Malavia
- Institute of Medical Sciences, School of Medicine, Medical Sciences & Nutrition, University of Aberdeen, Foresterhill, Aberdeen, AB25 2ZD, UK
- MRC Centre for Medical Mycology, Geoffrey Pope Building, University of Exeter, Stocker Road, Exeter, EX4 4QD, UK
| | - Takashi Kubota
- Institute of Medical Sciences, School of Medicine, Medical Sciences & Nutrition, University of Aberdeen, Foresterhill, Aberdeen, AB25 2ZD, UK.
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4
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Bhagwat M, Nagar S, Kaur P, Mehta R, Vancurova I, Vancura A. Replication stress inhibits synthesis of histone mRNAs in yeast by removing Spt10p and Spt21p from the histone promoters. J Biol Chem 2021; 297:101246. [PMID: 34582893 PMCID: PMC8551654 DOI: 10.1016/j.jbc.2021.101246] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 09/17/2021] [Accepted: 09/23/2021] [Indexed: 12/27/2022] Open
Abstract
Proliferating cells coordinate histone and DNA synthesis to maintain correct stoichiometry for chromatin assembly. Histone mRNA levels must be repressed when DNA replication is inhibited to prevent toxicity and genome instability due to free non-chromatinized histone proteins. In mammalian cells, replication stress triggers degradation of histone mRNAs, but it is unclear if this mechanism is conserved from other species. The aim of this study was to identify the histone mRNA decay pathway in the yeast Saccharomyces cerevisiae and determine the mechanism by which DNA replication stress represses histone mRNAs. Using reverse transcription-quantitative PCR and chromatin immunoprecipitation–quantitative PCR, we show here that histone mRNAs can be degraded by both 5′ → 3′ and 3′ → 5′ pathways; however, replication stress does not trigger decay of histone mRNA in yeast. Rather, replication stress inhibits transcription of histone genes by removing the histone gene–specific transcription factors Spt10p and Spt21p from histone promoters, leading to disassembly of the preinitiation complexes and eviction of RNA Pol II from histone genes by a mechanism facilitated by checkpoint kinase Rad53p and histone chaperone Asf1p. In contrast, replication stress does not remove SCB-binding factor transcription complex, another activator of histone genes, from the histone promoters, suggesting that Spt10p and Spt21p have unique roles in the transcriptional downregulation of histone genes during replication stress. Together, our data show that, unlike in mammalian cells, replication stress in yeast does not trigger decay of histone mRNAs but inhibits histone transcription.
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Affiliation(s)
- Madhura Bhagwat
- Department of Biological Sciences, St John's University, Queens, New York, USA
| | - Shreya Nagar
- Department of Biological Sciences, St John's University, Queens, New York, USA
| | - Pritpal Kaur
- Department of Biological Sciences, St John's University, Queens, New York, USA
| | - Riddhi Mehta
- Department of Biological Sciences, St John's University, Queens, New York, USA
| | - Ivana Vancurova
- Department of Biological Sciences, St John's University, Queens, New York, USA
| | - Ales Vancura
- Department of Biological Sciences, St John's University, Queens, New York, USA.
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5
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Chacin E, Bansal P, Reusswig KU, Diaz-Santin LM, Ortega P, Vizjak P, Gómez-González B, Müller-Planitz F, Aguilera A, Pfander B, Cheung ACM, Kurat CF. A CDK-regulated chromatin segregase promoting chromosome replication. Nat Commun 2021; 12:5224. [PMID: 34471130 PMCID: PMC8410769 DOI: 10.1038/s41467-021-25424-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Accepted: 08/05/2021] [Indexed: 11/09/2022] Open
Abstract
The replication of chromosomes during S phase is critical for cellular and organismal function. Replicative stress can result in genome instability, which is a major driver of cancer. Yet how chromatin is made accessible during eukaryotic DNA synthesis is poorly understood. Here, we report the characterization of a chromatin remodeling enzyme-Yta7-entirely distinct from classical SNF2-ATPase family remodelers. Yta7 is a AAA+ -ATPase that assembles into ~1 MDa hexameric complexes capable of segregating histones from DNA. The Yta7 chromatin segregase promotes chromosome replication both in vivo and in vitro. Biochemical reconstitution experiments using purified proteins revealed that the enzymatic activity of Yta7 is regulated by S phase-forms of Cyclin-Dependent Kinase (S-CDK). S-CDK phosphorylation stimulates ATP hydrolysis by Yta7, promoting nucleosome disassembly and chromatin replication. Our results present a mechanism for how cells orchestrate chromatin dynamics in co-ordination with the cell cycle machinery to promote genome duplication during S phase.
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Affiliation(s)
- Erika Chacin
- Molecular Biology Division, Biomedical Center Munich, Ludwig-Maximilians-Universität, Munich, Planegg-Martinsried, Germany
| | - Priyanka Bansal
- Molecular Biology Division, Biomedical Center Munich, Ludwig-Maximilians-Universität, Munich, Planegg-Martinsried, Germany
| | - Karl-Uwe Reusswig
- Max Planck Institute of Biochemistry, DNA Replication and Genome Integrity, Planegg-Martinsried, Germany
| | - Luis M Diaz-Santin
- Department of Structural and Molecular Biology, Institute of Structural and Molecular Biology, University College London, London, UK.,Institute of Structural and Molecular Biology, Biological Sciences, Birkbeck College, London, UK
| | - Pedro Ortega
- Andalusian Molecular Biology and Regenerative Medicine Centre-CABIMER, University of Seville-CSIC, Seville, Spain
| | - Petra Vizjak
- Molecular Biology Division, Biomedical Center Munich, Ludwig-Maximilians-Universität, Munich, Planegg-Martinsried, Germany
| | - Belen Gómez-González
- Andalusian Molecular Biology and Regenerative Medicine Centre-CABIMER, University of Seville-CSIC, Seville, Spain
| | - Felix Müller-Planitz
- Molecular Biology Division, Biomedical Center Munich, Ludwig-Maximilians-Universität, Munich, Planegg-Martinsried, Germany.,Institute of Physiological Chemistry, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Andrés Aguilera
- Andalusian Molecular Biology and Regenerative Medicine Centre-CABIMER, University of Seville-CSIC, Seville, Spain
| | - Boris Pfander
- Max Planck Institute of Biochemistry, DNA Replication and Genome Integrity, Planegg-Martinsried, Germany
| | - Alan C M Cheung
- Department of Structural and Molecular Biology, Institute of Structural and Molecular Biology, University College London, London, UK.,Institute of Structural and Molecular Biology, Biological Sciences, Birkbeck College, London, UK.,School of Biochemistry, University of Bristol, Bristol, UK
| | - Christoph F Kurat
- Molecular Biology Division, Biomedical Center Munich, Ludwig-Maximilians-Universität, Munich, Planegg-Martinsried, Germany.
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6
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Claude KL, Bureik D, Chatzitheodoridou D, Adarska P, Singh A, Schmoller KM. Transcription coordinates histone amounts and genome content. Nat Commun 2021; 12:4202. [PMID: 34244507 PMCID: PMC8270936 DOI: 10.1038/s41467-021-24451-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Accepted: 06/18/2021] [Indexed: 02/06/2023] Open
Abstract
Biochemical reactions typically depend on the concentrations of the molecules involved, and cell survival therefore critically depends on the concentration of proteins. To maintain constant protein concentrations during cell growth, global mRNA and protein synthesis rates are tightly linked to cell volume. While such regulation is appropriate for most proteins, certain cellular structures do not scale with cell volume. The most striking example of this is the genomic DNA, which doubles during the cell cycle and increases with ploidy, but is independent of cell volume. Here, we show that the amount of histone proteins is coupled to the DNA content, even though mRNA and protein synthesis globally increase with cell volume. As a consequence, and in contrast to the global trend, histone concentrations decrease with cell volume but increase with ploidy. We find that this distinct coordination of histone homeostasis and genome content is already achieved at the transcript level, and is an intrinsic property of histone promoters that does not require direct feedback mechanisms. Mathematical modeling and histone promoter truncations reveal a simple and generalizable mechanism to control the cell volume- and ploidy-dependence of a given gene through the balance of the initiation and elongation rates.
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Affiliation(s)
- Kora-Lee Claude
- Institute of Functional Epigenetics, Helmholtz Zentrum München, Neuherberg, Germany
| | - Daniela Bureik
- Institute of Functional Epigenetics, Helmholtz Zentrum München, Neuherberg, Germany
| | | | - Petia Adarska
- Institute of Functional Epigenetics, Helmholtz Zentrum München, Neuherberg, Germany
| | - Abhyudai Singh
- Department of Electrical & Computer Engineering, University of Delaware, Newark, DE, USA
| | - Kurt M Schmoller
- Institute of Functional Epigenetics, Helmholtz Zentrum München, Neuherberg, Germany.
- German Center for Diabetes Research (DZD), Neuherberg, Germany.
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7
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The ATAD2/ANCCA homolog Yta7 cooperates with Scm3 HJURP to deposit Cse4 CENP-A at the centromere in yeast. Proc Natl Acad Sci U S A 2020; 117:5386-5393. [PMID: 32079723 DOI: 10.1073/pnas.1917814117] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The AAA+ ATPase and bromodomain factor ATAD2/ANCCA is overexpressed in many types of cancer, but how it contributes to tumorigenesis is not understood. Here, we report that the Saccharomyces cerevisiae homolog Yta7ATAD2 is a deposition factor for the centromeric histone H3 variant Cse4CENP-A at the centromere in yeast. Yta7ATAD2 regulates the levels of centromeric Cse4CENP-A in that yta7∆ causes reduced Cse4CENP-A deposition, whereas YTA7 overexpression causes increased Cse4CENP-A deposition. Yta7ATAD2 coimmunoprecipitates with Cse4CENP-A and is associated with the centromere, arguing for a direct role of Yta7ATAD2 in Cse4CENP-A deposition. Furthermore, increasing centromeric Cse4CENP-A levels by YTA7 overexpression requires the activity of Scm3HJURP, the centromeric nucleosome assembly factor. Importantly, Yta7ATAD2 interacts in vivo with Scm3HJURP, indicating that Yta7ATAD2 is a cochaperone for Scm3HJURP The absence of Yta7 causes defects in growth and chromosome segregation with mutations in components of the inner kinetochore (CTF19/CCAN, Mif2CENP-C, Cbf1). Since Yta7ATAD2 is an AAA+ ATPase and potential hexameric unfoldase, our results suggest that it may unfold the Cse4CENP-A histone and hand it over to Scm3HJURP for subsequent deposition in the centromeric nucleosome. Furthermore, our findings suggest that ATAD2 overexpression may enhance malignant transformation in humans by misregulating centromeric CENP-A levels, thus leading to defects in kinetochore assembly and chromosome segregation.
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8
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Encinas-García T, Loreto-Quiroz DL, Mendoza-Cano F, Peña-Rodriguez A, Fimbres-Olivarria D, Re-Vega ED, Sánchez-Paz A. White spot syndrome virus down-regulates expression of histones H2A and H4 of Penaeus vannamei to promote viral replication. DISEASES OF AQUATIC ORGANISMS 2019; 137:73-79. [PMID: 31802744 DOI: 10.3354/dao03428] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The white spot syndrome virus (WSSV) is a highly lethal and contagious pathogen to most cultivated shrimp species. The WSSV genome contains the ICP11 gene and its encoded protein acts as a multifunctinal DNA mimic protein that disrupts the nucleosome assembly by binding to the histone proteins H2A and H3. In addition, WSSV provokes severe nuclear hypertrophy and DNA damage. However, little is known about the influence of WSSV on the expression of the host's genes encoding for histones. Therefore, we investigated the effect of WSSV infection on the expression of the genes encoding histones in shrimp Penaeus vannamei. An RT-qPCR assay was performed to evaluate the temporal expression of H2A and H4 transcripts in the shrimp. Significant changes were observed in the expression of these genes, which coincided with the dynamics of replication of the virus. H2A reached its maximum expression levels at 12 hpi. Thus, it may be suggested that this is a viral strategy to evade the host's immune response in order to promote viral replication.
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Affiliation(s)
- Trinidad Encinas-García
- Laboratorio de Análisis, Referencia y Diagnóstico en Sanidad Acuícola, Centro de Investigaciones Biológicas del Noroeste (CIBNOR), Calle Hermosa 101, Col. Los Ángeles, Hermosillo, Sonora 83106, México
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9
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Mei Q, Xu C, Gogol M, Tang J, Chen W, Yu X, Workman JL, Li S. Set1-catalyzed H3K4 trimethylation antagonizes the HIR/Asf1/Rtt106 repressor complex to promote histone gene expression and chronological life span. Nucleic Acids Res 2019; 47:3434-3449. [PMID: 30759223 PMCID: PMC6468302 DOI: 10.1093/nar/gkz101] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2018] [Revised: 02/05/2019] [Accepted: 02/07/2019] [Indexed: 01/07/2023] Open
Abstract
Aging is the main risk factor for many prevalent diseases. However, the molecular mechanisms regulating aging at the cellular level are largely unknown. Using single cell yeast as a model organism, we found that reducing yeast histone proteins accelerates chronological aging and increasing histone supply extends chronological life span. We sought to identify pathways that regulate chronological life span by controlling intracellular histone levels. Thus, we screened the histone H3/H4 mutant library to uncover histone residues and posttranslational modifications that regulate histone gene expression. We discovered 15 substitution mutations with reduced histone proteins and 5 mutations with increased histone proteins. Among these mutations, we found Set1 complex-catalyzed H3K4me3 promotes histone gene transcription and maintains normal chronological life span. Unlike the canonical functions of H3K4me3 in gene expression, H3K4me3 facilitates histone gene transcription by acting as a boundary to restrict the spread of the repressive HIR/Asf1/Rtt106 complex from histone gene promoters. Collectively, our study identified a novel mechanism by which H3K4me3 antagonizes the HIR/Asf1/Rtt106 repressor complex to promote histone gene expression and extend chronological life span.
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Affiliation(s)
- Qianyun Mei
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, Hubei 430062, China
| | - Chen Xu
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, Hubei 430062, China
| | - Madelaine Gogol
- Stowers Institute for Medical Research, 1000 E. 50th Street, Kansas City, MO 64110, USA
| | - Jie Tang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, Hubei 430062, China
| | - Wanping Chen
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, Hubei 430062, China
| | - Xilan Yu
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, Hubei 430062, China
| | - Jerry L Workman
- Stowers Institute for Medical Research, 1000 E. 50th Street, Kansas City, MO 64110, USA
| | - Shanshan Li
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, Hubei 430062, China
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10
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Gali VK, Dickerson D, Katou Y, Fujiki K, Shirahige K, Owen-Hughes T, Kubota T, Donaldson AD. Identification of Elg1 interaction partners and effects on post-replication chromatin re-formation. PLoS Genet 2018; 14:e1007783. [PMID: 30418970 PMCID: PMC6258251 DOI: 10.1371/journal.pgen.1007783] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Revised: 11/26/2018] [Accepted: 10/23/2018] [Indexed: 12/04/2022] Open
Abstract
Elg1, the major subunit of a Replication Factor C-like complex, is critical to ensure genomic stability during DNA replication, and is implicated in controlling chromatin structure. We investigated the consequences of Elg1 loss for the dynamics of chromatin re-formation following DNA replication. Measurement of Okazaki fragment length and the micrococcal nuclease sensitivity of newly replicated DNA revealed a defect in nucleosome organization in the absence of Elg1. Using a proteomic approach to identify Elg1 binding partners, we discovered that Elg1 interacts with Rtt106, a histone chaperone implicated in replication-coupled nucleosome assembly that also regulates transcription. A central role for Elg1 is the unloading of PCNA from chromatin following DNA replication, so we examined the relative importance of Rtt106 and PCNA unloading for chromatin reassembly following DNA replication. We find that the major cause of the chromatin organization defects of an ELG1 mutant is PCNA retention on DNA following replication, with Rtt106-Elg1 interaction potentially playing a contributory role.
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Affiliation(s)
- Vamsi K. Gali
- Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, Scotland, United Kingdom
| | - David Dickerson
- Centre for Gene Regulation and Expression, University of Dundee, Dundee, Scotland, United Kingdom
| | - Yuki Katou
- Research Center for Epigenetic Disease, Institute of Molecular and Cellular Biosciences, University of Tokyo, Tokyo, Japan
| | - Katsunori Fujiki
- Research Center for Epigenetic Disease, Institute of Molecular and Cellular Biosciences, University of Tokyo, Tokyo, Japan
| | - Katsuhiko Shirahige
- Research Center for Epigenetic Disease, Institute of Molecular and Cellular Biosciences, University of Tokyo, Tokyo, Japan
| | - Tom Owen-Hughes
- Centre for Gene Regulation and Expression, University of Dundee, Dundee, Scotland, United Kingdom
| | - Takashi Kubota
- Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, Scotland, United Kingdom
| | - Anne D. Donaldson
- Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, Scotland, United Kingdom
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11
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Mei Q, Huang J, Chen W, Tang J, Xu C, Yu Q, Cheng Y, Ma L, Yu X, Li S. Regulation of DNA replication-coupled histone gene expression. Oncotarget 2017; 8:95005-95022. [PMID: 29212286 PMCID: PMC5706932 DOI: 10.18632/oncotarget.21887] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Accepted: 09/20/2017] [Indexed: 12/21/2022] Open
Abstract
The expression of core histone genes is cell cycle regulated. Large amounts of histones are required to restore duplicated chromatin during S phase when DNA replication occurs. Over-expression and excess accumulation of histones outside S phase are toxic to cells and therefore cells need to restrict histone expression to S phase. Misregulation of histone gene expression leads to defects in cell cycle progression, genome stability, DNA damage response and transcriptional regulation. Here, we discussed the factors involved in histone gene regulation as well as the underlying mechanism. Understanding the histone regulation mechanism will shed lights on elucidating the side effects of certain cancer chemotherapeutic drugs and developing potential biomarkers for tumor cells.
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Affiliation(s)
- Qianyun Mei
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan, Hubei 430062, China
| | - Junhua Huang
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan, Hubei 430062, China
| | - Wanping Chen
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan, Hubei 430062, China.,Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan, Hubei 430062, China
| | - Jie Tang
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan, Hubei 430062, China
| | - Chen Xu
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan, Hubei 430062, China
| | - Qi Yu
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan, Hubei 430062, China
| | - Ying Cheng
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan, Hubei 430062, China
| | - Lixin Ma
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan, Hubei 430062, China.,Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan, Hubei 430062, China
| | - Xilan Yu
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan, Hubei 430062, China.,Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan, Hubei 430062, China
| | - Shanshan Li
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan, Hubei 430062, China.,Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan, Hubei 430062, China
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12
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Jenull S, Tscherner M, Gulati M, Nobile CJ, Chauhan N, Kuchler K. The Candida albicans HIR histone chaperone regulates the yeast-to-hyphae transition by controlling the sensitivity to morphogenesis signals. Sci Rep 2017; 7:8308. [PMID: 28814742 PMCID: PMC5559454 DOI: 10.1038/s41598-017-08239-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Accepted: 07/10/2017] [Indexed: 01/01/2023] Open
Abstract
Morphological plasticity such as the yeast-to-hyphae transition is a key virulence factor of the human fungal pathogen Candida albicans. Hyphal formation is controlled by a multilayer regulatory network composed of environmental sensing, signaling, transcriptional modulators as well as chromatin modifications. Here, we demonstrate a novel role for the replication-independent HIR histone chaperone complex in fungal morphogenesis. HIR operates as a crucial modulator of hyphal development, since genetic ablation of the HIR complex subunit Hir1 decreases sensitivity to morphogenetic stimuli. Strikingly, HIR1-deficient cells display altered transcriptional amplitudes upon hyphal initiation, suggesting that Hir1 affects transcription by establishing transcriptional thresholds required for driving morphogenetic cell-fate decisions. Furthermore, ectopic expression of the transcription factor Ume6, which facilitates hyphal maintenance, rescues filamentation defects of hir1Δ/Δ cells, suggesting that Hir1 impacts the early phase of hyphal initiation. Hence, chromatin chaperone-mediated fine-tuning of transcription is crucial for driving morphogenetic conversions in the fungal pathogen C. albicans.
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Affiliation(s)
- Sabrina Jenull
- Medical University of Vienna, Max F. Perutz Laboratories, Department of Medical Biochemistry, Campus Vienna Biocenter, Dr.-Bohr-Gasse 9/2, A-1030, Vienna, Austria
| | - Michael Tscherner
- Medical University of Vienna, Max F. Perutz Laboratories, Department of Medical Biochemistry, Campus Vienna Biocenter, Dr.-Bohr-Gasse 9/2, A-1030, Vienna, Austria
- Department of Systems Biology, Harvard Medical School, Boston, Massachusetts, 02115, USA
| | - Megha Gulati
- Department of Molecular and Cell Biology, School of Natural Sciences, University of California-Merced, Merced, CA, USA
| | - Clarissa J Nobile
- Department of Molecular and Cell Biology, School of Natural Sciences, University of California-Merced, Merced, CA, USA
| | - Neeraj Chauhan
- Public Health Research Institute, Department of Microbiology, Biochemistry and Molecular Genetics, New Jersey Medical School - Rutgers, The State University of New Jersey, Newark, New Jersey, USA
| | - Karl Kuchler
- Medical University of Vienna, Max F. Perutz Laboratories, Department of Medical Biochemistry, Campus Vienna Biocenter, Dr.-Bohr-Gasse 9/2, A-1030, Vienna, Austria.
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13
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Deletion of a Yci1 Domain Protein of Candida albicans Allows Homothallic Mating in MTL Heterozygous Cells. mBio 2016; 7:e00465-16. [PMID: 27118591 PMCID: PMC4850264 DOI: 10.1128/mbio.00465-16] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
It has been proposed that the ancestral fungus was mating competent and homothallic. However, many mating-competent fungi were initially classified as asexual because their mating capacity was hidden behind layers of regulation. For efficient in vitro mating, the essentially obligate diploid ascomycete pathogen Candida albicans has to change its mating type locus from heterozygous MTLa/α to homozygous MTLa/a or MTLα/α and then undergo an environmentally controlled epigenetic switch to the mating-competent opaque form. These requirements greatly reduce the potential for C. albicans mating. Deletion of the Yci1 domain gene OFR1 bypasses the need for C. albicans cells to change the mating type locus from heterozygous to homozygous prior to switching to the opaque form and mating and allows homothallic mating of MTL heterozygous strains. This bypass is carbon source dependent and does not occur when cells are grown on glucose. Transcriptional profiling of ofr1 mutant cells shows that in addition to regulating cell type and mating circuitry, Ofr1 is needed for proper regulation of histone and chitin biosynthesis gene expression. It appears that OFR1 is a key regulator in C. albicans and functions in part to maintain the cryptic mating phenotype of the pathogen. Candida albicans is a human fungal pathogen with a recently discovered, highly cryptic mating ability. For efficient mating, it has to lose heterozygosity at its mating type locus. Then, MTL homozygous strains can undergo an epigenetic switch to an elongated yeast state, termed the opaque form, and become mating competent. This infrequent two-step process greatly reduces the potential for mating; few strains are MTL homozygous, and the opaque state is unstable at the temperature of the mammalian host. C. albicans has a complex mechanism for mating that appears designed to ensure that mating is infrequent. Here, we have characterized a new gene, opaque-formation regulator 1 (OFR1). Deleting the OFR1 gene allows MTLa/α strains to mate efficiently with either mating type or even mate homothallically. It is possible that downregulating OFR1 in the host environment could allow mating in C. albicans by a route that does not involve MTL homozygosis.
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14
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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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15
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Cattaneo M, Morozumi Y, Perazza D, Boussouar F, Jamshidikia M, Rousseaux S, Verdel A, Khochbin S. Lessons from yeast on emerging roles of the ATAD2 protein family in gene regulation and genome organization. Mol Cells 2014; 37:851-6. [PMID: 25377252 PMCID: PMC4275701 DOI: 10.14348/molcells.2014.0258] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Accepted: 09/22/2014] [Indexed: 12/26/2022] Open
Abstract
ATAD2, a remarkably conserved, yet poorly characterized factor is found upregulated and associated with poor prognosis in a variety of independent cancers in human. Studies conducted on the yeast Saccharomyces cerevisiae ATAD2 homologue, Yta7, are now indicating that the members of this family may primarily be regulators of chromatin dynamics and that their action on gene expression could only be one facet of their general activity. In this review, we present an overview of the literature on Yta7 and discuss the possibility of translating these findings into other organisms to further define the involvement of ATAD2 and other members of its family in regulating chromatin structure and function both in normal and pathological situations.
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Affiliation(s)
- Matteo Cattaneo
- Team RNA and Epigenetics, Université Joseph Fourier – Grenoble 1, Institut Albert Bonniot, Faculté de Médecine, La Tronche Cedex,
France
- INSERM, U823, Université Joseph Fourier – Grenoble 1, Institut Albert Bonniot, Faculté de Médecine, La Tronche Cedex,
France
| | - Yuichi Morozumi
- Team Epigenetics and Cell Signaling, Université Joseph Fourier – Grenoble 1, Institut Albert Bonniot, Faculté de Médecine, La Tronche Cedex,
France
- INSERM, U823, Université Joseph Fourier – Grenoble 1, Institut Albert Bonniot, Faculté de Médecine, La Tronche Cedex,
France
| | - Daniel Perazza
- Team RNA and Epigenetics, Université Joseph Fourier – Grenoble 1, Institut Albert Bonniot, Faculté de Médecine, La Tronche Cedex,
France
- INSERM, U823, Université Joseph Fourier – Grenoble 1, Institut Albert Bonniot, Faculté de Médecine, La Tronche Cedex,
France
| | - Fayçal Boussouar
- Team Epigenetics and Cell Signaling, Université Joseph Fourier – Grenoble 1, Institut Albert Bonniot, Faculté de Médecine, La Tronche Cedex,
France
- INSERM, U823, Université Joseph Fourier – Grenoble 1, Institut Albert Bonniot, Faculté de Médecine, La Tronche Cedex,
France
| | - Mahya Jamshidikia
- Team Epigenetics and Cell Signaling, Université Joseph Fourier – Grenoble 1, Institut Albert Bonniot, Faculté de Médecine, La Tronche Cedex,
France
- INSERM, U823, Université Joseph Fourier – Grenoble 1, Institut Albert Bonniot, Faculté de Médecine, La Tronche Cedex,
France
| | - Sophie Rousseaux
- Team Epigenetics and Cell Signaling, Université Joseph Fourier – Grenoble 1, Institut Albert Bonniot, Faculté de Médecine, La Tronche Cedex,
France
- INSERM, U823, Université Joseph Fourier – Grenoble 1, Institut Albert Bonniot, Faculté de Médecine, La Tronche Cedex,
France
| | - André Verdel
- Team RNA and Epigenetics, Université Joseph Fourier – Grenoble 1, Institut Albert Bonniot, Faculté de Médecine, La Tronche Cedex,
France
- INSERM, U823, Université Joseph Fourier – Grenoble 1, Institut Albert Bonniot, Faculté de Médecine, La Tronche Cedex,
France
| | - Saadi Khochbin
- Team Epigenetics and Cell Signaling, Université Joseph Fourier – Grenoble 1, Institut Albert Bonniot, Faculté de Médecine, La Tronche Cedex,
France
- INSERM, U823, Université Joseph Fourier – Grenoble 1, Institut Albert Bonniot, Faculté de Médecine, La Tronche Cedex,
France
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16
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Abstract
The extent of chromatin compaction is a fundamental driver of nuclear metabolism . Yta7 is a chromatin-associated AAA-ATPase, the human ortholog of which, ANCCA/ATAD2 transcriptionally activates pathways of malignancy in a broad range of cancers. Yta7 directly binds histone H3, and bulk chromatin exhibits increased nucleosomal density in yta7Δ mutants. The suppression of yta7Δ mutant growth and transcriptional phenotypes in budding yeast by decreased dosage of histones H3 and H4 indicates the acute sensitivity of cells to deviations in nucleosome spacing. This study investigated the global changes in chromatin structure upon Yta7 loss or overexpression and determined which of these effects reflected direct Yta7 activity. Metagene analysis of Yta7's genome-wide localization indicated peak binding of Yta7 just downstream of the transcription start site. Cells lacking Yta7 exhibited increased nucleosome density within genes downstream of the +1 nucleosome, as defined by decreased internucleosomal distance, resulting in progressively 5'-shifted nucleosomes within the gene. In contrast, cells overexpressing Yta7 displayed profound 3'-shifts in nucleosome position and reduced nucleosome density within genes. Importantly, Yta7-bound regions were enriched for nucleosomal shifts, indicating that Yta7 acted locally to modulate nucleosome spacing. The phenotype of cells lacking both Yta7 and Rtt106, the histone H3/H4 chaperone, indicated that Yta7 functions in both Rtt106-dependent and Rtt106-independent ways to modulate nucleosome spacing within genes. This study suggested that Yta7 affected nucleosome density throughout the gene by both blocking Rtt106 from entering the gene, as shown previously at HTA1, and facilitating the loss of nucleosomes from the 5'-end.
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17
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Genome-wide mapping of yeast histone chaperone anti-silencing function 1 reveals its role in condensin binding with chromatin. PLoS One 2014; 9:e108652. [PMID: 25264624 PMCID: PMC4181348 DOI: 10.1371/journal.pone.0108652] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Accepted: 09/01/2014] [Indexed: 12/23/2022] Open
Abstract
Genome-wide participation and importance of the histone chaperone Asf1 (Anti-Silencing Function 1) in diverse DNA transactions like replication, repair, heterochromatic silencing and transcription are well documented. Yet its genome-wide targets have not been reported. Using ChIP-seq method, we found that yeast Asf1 associates with 590 unique targets including centromeres, telomeres and condensin-binding sites. It is found selectively on highly transcribed regions, which include replication fork pause sites. Asf1 preferentially associates with the genes transcribed by RNA polymerase (pol) III where its presence affects RNA production and replication-independent histone exchange. On pol II-transcribed genes, a negative correlation is found between Asf1 and nucleosome occupancy. It is not enriched on most of the reported sites of histone exchange or on the genes, which are misregulated in the asf1Δ cells. Interestingly, chromosome-wide distributions of Asf1 and one of the condensin subunits, Brn1 show a nearly identical pattern. Moreover, Brn1 shows reduced occupancy at various condensin-binding sites in asf1Δ cells. These results along with high association of Asf1 with heterochromatic centromeres and telomeres ascribe novel roles to Asf1 in condensin loading and chromatin dynamics.
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18
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Cell cycle-regulated oscillator coordinates core histone gene transcription through histone acetylation. Proc Natl Acad Sci U S A 2014; 111:14124-9. [PMID: 25228766 DOI: 10.1073/pnas.1414024111] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
DNA replication occurs during the synthetic (S) phase of the eukaryotic cell cycle and features a dramatic induction of histone gene expression for concomitant chromatin assembly. Ectopic production of core histones outside of S phase is toxic, underscoring the critical importance of regulatory pathways that ensure proper expression of histone genes. Several regulators of histone gene expression in the budding yeast Saccharomyces cerevisiae are known, yet the key oscillator responsible for restricting gene expression to S phase has remained elusive. Here, we show that suppressor of Ty (Spt)10, a putative histone acetyltransferase, and its binding partner Spt21 are key determinants of S-phase-specific histone gene expression. We show that Spt21 abundance is restricted to S phase in part by anaphase promoting complex Cdc20-homologue 1 (APC(Cdh1)) and that it is recruited to histone gene promoters in S phase by Spt10. There, Spt21-Spt10 enables the recruitment of a cascade of regulators, including histone chaperones and the histone-acetyltransferase general control nonderepressible (Gcn) 5, which we hypothesize lead to histone acetylation and consequent transcription activation.
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19
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Unexpected function of the glucanosyltransferase Gas1 in the DNA damage response linked to histone H3 acetyltransferases in Saccharomyces cerevisiae. Genetics 2014; 196:1029-39. [PMID: 24532730 DOI: 10.1534/genetics.113.158824] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Chromatin organization and structure are crucial for transcriptional regulation, DNA replication, and damage repair. Although initially characterized in remodeling cell wall glucans, the β-1,3-glucanosyltransferase Gas1 was recently discovered to regulate transcriptional silencing in a manner separable from its activity at the cell wall. However, the function of Gas1 in modulating chromatin remains largely unexplored. Our genetic characterization revealed that GAS1 had critical interactions with genes encoding the histone H3 lysine acetyltransferases Gcn5 and Sas3. Specifically, whereas the gas1 gcn5 double mutant was synthetically lethal, deletion of both GAS1 and SAS3 restored silencing in Saccharomyces cerevisiae. The loss of GAS1 also led to broad DNA damage sensitivity with reduced Rad53 phosphorylation and defective cell cycle checkpoint activation following exposure to select genotoxins. Deletion of SAS3 in the gas1 background restored both Rad53 phosphorylation and checkpoint activation following exposure to genotoxins that trigger the DNA replication checkpoint. Our analysis thus uncovers previously unsuspected functions for both Gas1 and Sas3 in DNA damage response and cell cycle regulation.
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20
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Kurat CF, Recht J, Radovani E, Durbic T, Andrews B, Fillingham J. Regulation of histone gene transcription in yeast. Cell Mol Life Sci 2014; 71:599-613. [PMID: 23974242 PMCID: PMC11113579 DOI: 10.1007/s00018-013-1443-9] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Revised: 07/10/2013] [Accepted: 07/29/2013] [Indexed: 12/11/2022]
Abstract
Histones are the primary protein component of chromatin, the mixture of DNA and proteins that packages the genetic material in eukaryotes. Large amounts of histones are required during the S phase of the cell cycle when genome replication occurs. However, ectopic expression of histones during other cell cycle phases is toxic; thus, histone expression is restricted to the S phase and is tightly regulated at multiple levels, including transcriptional, post-transcriptional, translational, and post-translational. In this review, we discuss mechanisms of regulation of histone gene expression with emphasis on the transcriptional regulation of the replication-dependent histone genes in the model yeast Saccharomyces cerevisiae.
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Affiliation(s)
- Christoph F. Kurat
- The Donnelly Center, University of Toronto, Toronto, ON M5S 3E1 Canada
- Banting and Best Department of Medical Research, University of Toronto, Toronto, ON M5S 3E1 Canada
| | | | - Ernest Radovani
- Department of Chemistry and Biology, Ryerson University, Toronto, ON M5B 2K3 Canada
| | - Tanja Durbic
- Department of Chemistry and Biology, Ryerson University, Toronto, ON M5B 2K3 Canada
| | - Brenda Andrews
- The Donnelly Center, University of Toronto, Toronto, ON M5S 3E1 Canada
- Banting and Best Department of Medical Research, University of Toronto, Toronto, ON M5S 3E1 Canada
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 3E1 Canada
| | - Jeffrey Fillingham
- Department of Chemistry and Biology, Ryerson University, Toronto, ON M5B 2K3 Canada
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21
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Cell-cycle perturbations suppress the slow-growth defect of spt10Δ mutants in Saccharomyces cerevisiae. G3-GENES GENOMES GENETICS 2013; 3:573-83. [PMID: 23450643 PMCID: PMC3583463 DOI: 10.1534/g3.112.005389] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/18/2012] [Accepted: 01/17/2013] [Indexed: 01/05/2023]
Abstract
Spt10 is a putative acetyltransferase of Saccharomyces cerevisiae that directly activates the transcription of histone genes. Deletion of SPT10 causes a severe slow growth phenotype, showing that Spt10 is critical for normal cell division. To gain insight into the function of Spt10, we identified mutations that impair or improve the growth of spt10 null (spt10Δ) mutants. Mutations that cause lethality in combination with spt10Δ include particular components of the SAGA complex as well as asf1Δ and hir1Δ. Partial suppressors of the spt10Δ growth defect include mutations that perturb cell-cycle progression through the G1/S transition, S phase, and G2/M. Consistent with these results, slowing of cell-cycle progression by treatment with hydroxyurea or growth on medium containing glycerol as the carbon source also partially suppresses the spt10Δ slow-growth defect. In addition, mutations that impair the Lsm1-7-Pat1 complex, which regulates decapping of polyadenylated mRNAs, also partially suppress the spt10Δ growth defect. Interestingly, suppression of the spt10Δ growth defect is not accompanied by a restoration of normal histone mRNA levels. These findings suggest that Spt10 has multiple roles during cell division.
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