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Schwer B, Innokentev A, Sanchez AM, Garg A, Shuman S. Suppression of inositol pyrophosphate toxicosis and hyper-repression of the fission yeast PHO regulon by loss-of-function mutations in chromatin remodelers Snf22 and Sol1. mBio 2024; 15:e0125224. [PMID: 38899862 PMCID: PMC11253589 DOI: 10.1128/mbio.01252-24] [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: 04/30/2024] [Accepted: 05/06/2024] [Indexed: 06/21/2024] Open
Abstract
Inositol pyrophosphates are signaling molecules that regulate cellular phosphate homeostasis in eukaryal taxa. In fission yeast, where the phosphate regulon (comprising phosphate acquisition genes pho1, pho84, and tgp1) is repressed under phosphate-replete conditions by lncRNA-mediated transcriptional interference, mutations of inositol pyrophosphatases that increase IP8 levels derepress the PHO regulon by eliciting precocious termination of lncRNA transcription. Asp1 pyrophosphatase mutations resulting in too much IP8 are cytotoxic in YES medium owing to overexpression of glycerophosphodiester transporter Tgp1. IP8 toxicosis is ameliorated by mutations in cleavage/polyadenylation and termination factors, perturbations of the Pol2 CTD code, and mutations in SPX domain proteins that act as inositol pyrophosphate sensors. Here, we show that IP8 toxicity is alleviated by deletion of snf22+, the gene encoding the ATPase subunit of the SWI/SNF chromatin remodeling complex, by an ATPase-inactivating snf22-(D996A-E997A) allele, and by deletion of the gene encoding SWI/SNF subunit Sol1. Deletion of snf22+ hyper-repressed pho1 expression in phosphate-replete cells; suppressed the pho1 derepression elicited by mutations in Pol2 CTD, termination factor Seb1, Asp1 pyrophosphatase, and 14-3-3 protein Rad24 (that favor precocious prt lncRNA termination); and delayed pho1 induction during phosphate starvation. RNA analysis and lack of mutational synergies suggest that Snf22 is not impacting 3'-processing/termination. Using reporter assays, we find that Snf22 is important for the activity of the tgp1 and pho1 promoters, but not for the promoters that drive the synthesis of the PHO-repressive lncRNAs. Transcription profiling of snf22∆ and snf22-(D996A-E997A) cells identified an additional set of 66 protein-coding genes that were downregulated in both mutants.IMPORTANCERepression of the fission yeast PHO genes tgp1, pho1, and pho84 by lncRNA-mediated interference is sensitive to inositol pyrophosphate dynamics. Cytotoxic asp1-STF alleles derepress the PHO genes via the action of IP8 as an agonist of precocious lncRNA 3'-processing/termination. IP8 toxicosis is alleviated by mutations of the Pol2 CTD and the 3'-processing/termination machinery that dampen the impact of toxic IP8 levels on termination. In this study, a forward genetic screen revealed that IP8 toxicity is suppressed by mutations of the Snf22 and Sol1 subunits of the SWI/SNF chromatin remodeling complex. Genetic and biochemical evidence indicates that the SWI/SNF is not affecting 3'-processing/termination or lncRNA promoter activity. Rather, SWI/SNF is critical for firing the PHO mRNA promoters. Our results implicate the ATP-dependent nucleosome remodeling activity of SWI/SNF as necessary to ensure full access of PHO-activating transcription factor Pho7 to its binding sites in the PHO mRNA promoters.
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Affiliation(s)
- Beate Schwer
- Department of Microbiology and Immunology, Weill Cornell Medical College, New York, New York, USA
| | - Aleksei Innokentev
- Molecular Biology Program, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Ana M. Sanchez
- Molecular Biology Program, Memorial Sloan Kettering Cancer Center, New York, New York, USA
- Gerstner Sloan Kettering Graduate School of Biomedical Sciences, New York, New York, USA
| | - Angad Garg
- Molecular Biology Program, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Stewart Shuman
- Molecular Biology Program, Memorial Sloan Kettering Cancer Center, New York, New York, USA
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2
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Rogers AM, Neri NR, Chigweshe L, Holmes SG. Histone variant H2A.Z and linker histone H1 influence chromosome condensation in Saccharomyces cerevisiae. Genetics 2024; 226:iyae022. [PMID: 38366024 PMCID: PMC10990423 DOI: 10.1093/genetics/iyae022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2023] [Revised: 10/15/2023] [Accepted: 01/17/2024] [Indexed: 02/18/2024] Open
Abstract
Chromosome condensation is essential for the fidelity of chromosome segregation during mitosis and meiosis. Condensation is associated both with local changes in nucleosome structure and larger-scale alterations in chromosome topology mediated by the condensin complex. We examined the influence of linker histone H1 and variant histone H2A.Z on chromosome condensation in budding yeast cells. Linker histone H1 has been implicated in local and global compaction of chromatin in multiple eukaryotes, but we observe normal condensation of the rDNA locus in yeast strains lacking H1. However, deletion of the yeast HTZ1 gene, coding for variant histone H2A.Z, causes a significant defect in rDNA condensation. Loss of H2A.Z does not change condensin association with the rDNA locus or significantly affect condensin mRNA levels. Prior studies reported that several phenotypes caused by loss of H2A.Z are suppressed by eliminating Swr1, a key component of the SWR complex that deposits H2A.Z in chromatin. We observe that an htz1Δ swr1Δ strain has near-normal rDNA condensation. Unexpectedly, we find that elimination of the linker histone H1 can also suppress the rDNA condensation defect of htz1Δ strains. Our experiments demonstrate that histone H2A.Z promotes chromosome condensation, in part by counteracting activities of histone H1 and the SWR complex.
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Affiliation(s)
- Anna M Rogers
- Department of Molecular Biology and Biochemistry, Wesleyan University, Middletown, CT 06459, USA
| | - Nola R Neri
- Department of Molecular Biology and Biochemistry, Wesleyan University, Middletown, CT 06459, USA
| | - Lorencia Chigweshe
- Department of Molecular Biology and Biochemistry, Wesleyan University, Middletown, CT 06459, USA
| | - Scott G Holmes
- Department of Molecular Biology and Biochemistry, Wesleyan University, Middletown, CT 06459, USA
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3
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Opalko HE, Miller KE, Kim HS, Vargas-Garcia CA, Singh A, Keogh MC, Moseley JB. Arf6 anchors Cdr2 nodes at the cell cortex to control cell size at division. J Cell Biol 2022; 221:e202109152. [PMID: 34958661 PMCID: PMC8931934 DOI: 10.1083/jcb.202109152] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 11/12/2021] [Accepted: 12/02/2021] [Indexed: 12/25/2022] Open
Abstract
Fission yeast cells prevent mitotic entry until a threshold cell surface area is reached. The protein kinase Cdr2 contributes to this size control system by forming multiprotein nodes that inhibit Wee1 at the medial cell cortex. Cdr2 node anchoring at the cell cortex is not fully understood. Through a genomic screen, we identified the conserved GTPase Arf6 as a component of Cdr2 signaling. Cells lacking Arf6 failed to divide at a threshold surface area and instead shifted to volume-based divisions at increased overall size. Arf6 stably localized to Cdr2 nodes in its GTP-bound but not GDP-bound state, and its guanine nucleotide exchange factor (GEF), Syt22, was required for both Arf6 node localization and proper size at division. In arf6Δ mutants, Cdr2 nodes detached from the membrane and exhibited increased dynamics. These defects were enhanced when arf6Δ was combined with other node mutants. Our work identifies a regulated anchor for Cdr2 nodes that is required for cells to sense surface area.
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Affiliation(s)
- Hannah E. Opalko
- Department of Biochemistry and Cell Biology, the Geisel School of Medicine at Dartmouth, Hanover, NH
| | - Kristi E. Miller
- Department of Biochemistry and Cell Biology, the Geisel School of Medicine at Dartmouth, Hanover, NH
| | - Hyun-Soo Kim
- Department of Cell Biology, Albert Einstein College of Medicine, New York, NY
| | - Cesar Augusto Vargas-Garcia
- Grupo de Investigación en Sistemas Agropecuarios Sostenibles, Corporación Colombiana de Investigación Agropecuaria – AGROSAVIA, Bogotá, Colombia
| | - Abhyudai Singh
- Department of Electrical and Computer Engineering, University of Delaware, Newark, DE
| | | | - James B. Moseley
- Department of Biochemistry and Cell Biology, the Geisel School of Medicine at Dartmouth, Hanover, NH
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4
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Breimann L, Morao AK, Kim J, Jimenez DS, Maryn N, Bikkasani K, Carrozza MJ, Albritton SE, Kramer M, Street LA, Cerimi K, Schumann VF, Bahry E, Preibisch S, Woehler A, Ercan S. The H4K20 demethylase DPY-21 regulates the dynamics of condensin DC binding. J Cell Sci 2021; 135:273768. [PMID: 34918745 PMCID: PMC8917352 DOI: 10.1242/jcs.258818] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 11/29/2021] [Indexed: 11/26/2022] Open
Abstract
Condensin is a multi-subunit structural maintenance of chromosomes (SMC) complex that binds to and compacts chromosomes. Here, we addressed the regulation of condensin binding dynamics using Caenorhabditis elegans condensin DC, which represses X chromosomes in hermaphrodites for dosage compensation. We established fluorescence recovery after photobleaching (FRAP) using the SMC4 homolog DPY-27 and showed that a well-characterized ATPase mutation abolishes DPY-27 binding to X chromosomes. Next, we performed FRAP in the background of several chromatin modifier mutants that cause varying degrees of X chromosome derepression. The greatest effect was in a null mutant of the H4K20me2 demethylase DPY-21, where the mobile fraction of condensin DC reduced from ∼30% to 10%. In contrast, a catalytic mutant of dpy-21 did not regulate condensin DC mobility. Hi-C sequencing data from the dpy-21 null mutant showed little change compared to wild-type data, uncoupling Hi-C-measured long-range DNA contacts from transcriptional repression of the X chromosomes. Taken together, our results indicate that DPY-21 has a non-catalytic role in regulating the dynamics of condensin DC binding, which is important for transcription repression. Summary: The histone demethylase DPY-21 has catalytic and non-catalytic roles in condensin DC-mediated X chromosome repression. The non-catalytic activity regulates dynamics of condensin DC binding to X chromosomes.
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Affiliation(s)
- Laura Breimann
- Department of Biology, Center for Genomics and Systems Biology, New York University, New York, NY, USA.,Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine, Berlin, Germany.,Institute for Biology, Humboldt University of Berlin, Berlin, Germany
| | - Ana Karina Morao
- Department of Biology, Center for Genomics and Systems Biology, New York University, New York, NY, USA
| | - Jun Kim
- Department of Biology, Center for Genomics and Systems Biology, New York University, New York, NY, USA
| | - David Sebastian Jimenez
- Department of Biology, Center for Genomics and Systems Biology, New York University, New York, NY, USA
| | - Nina Maryn
- Department of Biology, Center for Genomics and Systems Biology, New York University, New York, NY, USA
| | - Krishna Bikkasani
- Department of Biology, Center for Genomics and Systems Biology, New York University, New York, NY, USA
| | - Michael J Carrozza
- Department of Biology, Center for Genomics and Systems Biology, New York University, New York, NY, USA
| | - Sarah E Albritton
- Department of Biology, Center for Genomics and Systems Biology, New York University, New York, NY, USA
| | - Maxwell Kramer
- Department of Biology, Center for Genomics and Systems Biology, New York University, New York, NY, USA
| | - Lena Annika Street
- Department of Biology, Center for Genomics and Systems Biology, New York University, New York, NY, USA
| | - Kustrim Cerimi
- Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Vic-Fabienne Schumann
- Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Ella Bahry
- Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Stephan Preibisch
- Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine, Berlin, Germany.,Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Andrew Woehler
- Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Sevinç Ercan
- Department of Biology, Center for Genomics and Systems Biology, New York University, New York, NY, USA
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5
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Tsukii K, Takahata S, Murakami Y. Histone variant H2A.Z plays multiple roles in the maintenance of heterochromatin integrity. Genes Cells 2021; 27:93-112. [PMID: 34910346 DOI: 10.1111/gtc.12911] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 12/09/2021] [Accepted: 12/10/2021] [Indexed: 01/04/2023]
Abstract
H2A.Z, an evolutionally well-conserved histone H2A variant, is involved in many biological processes. Although the function of H2A.Z in euchromatic gene regulation is well known, its function and deposition mechanism in heterochromatin are still unclear. Here, we report that H2A.Z plays multiple roles in fission yeast heterochromatin. While a small amount of H2A.Z localizes at pericentromeric heterochromatin, loss of methylation of histone H3 at Lys9 (H3K9me) induces the accumulation of H2A.Z, which is dependent on the H2A.Z loader, SWR complex. The accumulated H2A.Z suppresses heterochromatic non-coding RNA transcription. This transcriptional repression activity requires the N-terminal tail of H2A.Z, which is involved in the regulation of euchromatic gene transcription. RNAi-defective cells, in which a substantial amount of H3K9me is retained by RNAi-independent heterochromatin assembly, also accumulate H2A.Z at heterochromatin, and the additional loss of H2A.Z in these cells triggers a further decrease in H3K9me. Our results suggest that H2A.Z facilitates RNAi-independent heterochromatin assembly by antagonizing the demethylation activity of Epe1, an eraser of H3K9me. Furthermore, H2A.Z suppresses Epe1-mediated transcriptional activation, which is required for subtelomeric gene repression. Our results provide novel evidence that H2A.Z plays diverse roles in chromatin silencing.
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Affiliation(s)
- Kazuki Tsukii
- Laboratory of Bioorganic Chemistry, Graduate School of Chemical Sciences and Engineering, Hokkaido University, Sapporo, Japan
| | - Shinya Takahata
- Laboratory of Bioorganic Chemistry, Graduate School of Chemical Sciences and Engineering, Hokkaido University, Sapporo, Japan.,Laboratory of Bioorganic Chemistry, Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo, Japan
| | - Yota Murakami
- Laboratory of Bioorganic Chemistry, Graduate School of Chemical Sciences and Engineering, Hokkaido University, Sapporo, Japan.,Laboratory of Bioorganic Chemistry, Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo, Japan
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6
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Lai D, Huang X, Wang C, Ow DW. Arabidopsis OXIDATIVE STRESS 3 enhances stress tolerance in Schizosaccharomyces pombe by promoting histone subunit replacement that upregulates drug-resistant genes. Genetics 2021; 219:6371188. [PMID: 34740252 DOI: 10.1093/genetics/iyab149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Accepted: 09/04/2021] [Indexed: 11/14/2022] Open
Abstract
Histone replacement in chromatin-remodeling plays an important role in eukaryotic gene expression. New histone variants replacing their canonical counterparts often lead to a change in transcription, including responses to stresses caused by temperature, drought, salinity, and heavy metals. In this study, we describe a chromatin-remodeling process triggered by eviction of Rad3/Tel1-phosphorylated H2Aα, in which a heterologous plant protein AtOXS3 can subsequently bind fission yeast HA2.Z and Swc2, a component of the SWR1 complex, to facilitate replacement of H2Aα with H2A.Z. The histone replacement increases occupancy of the oxidative stress-responsive transcription factor Pap1 at the promoters of at least three drug-resistant genes, which enhances their transcription and hence primes the cell for higher stress tolerance.
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Affiliation(s)
- Dingwang Lai
- Plant Gene Engineering Center, Chinese Academy of Sciences Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiuting Huang
- Plant Gene Engineering Center, Chinese Academy of Sciences Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Changhu Wang
- Plant Gene Engineering Center, Chinese Academy of Sciences Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
| | - David W Ow
- Plant Gene Engineering Center, Chinese Academy of Sciences Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
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7
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Li T, Petreaca RC, Forsburg SL. Schizosaccharomyces pombe KAT5 contributes to resection and repair of a DNA double-strand break. Genetics 2021; 218:6173406. [PMID: 33723569 DOI: 10.1093/genetics/iyab042] [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: 02/02/2021] [Accepted: 03/04/2021] [Indexed: 11/14/2022] Open
Abstract
Chromatin remodeling is essential for effective repair of a DNA double-strand break (DSB). KAT5 (Schizosaccharomyces pombe Mst1, human TIP60) is a MYST family histone acetyltransferase conserved from yeast to humans that coordinates various DNA damage response activities at a DNA DSB, including histone remodeling and activation of the DNA damage checkpoint. In S. pombe, mutations in mst1+ causes sensitivity to DNA damaging drugs. Here we show that Mst1 is recruited to DSBs. Mutation of mst1+ disrupts recruitment of repair proteins and delays resection. These defects are partially rescued by deletion of pku70, which has been previously shown to antagonize repair by homologous recombination (HR). These phenotypes of mst1 are similar to pht1-4KR, a nonacetylatable form of histone variant H2A.Z, which has been proposed to affect resection. Our data suggest that Mst1 functions to direct repair of DSBs toward HR pathways by modulating resection at the DSB.
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Affiliation(s)
- Tingting Li
- Program of Molecular and Computational Biology, University of Southern California, Los Angeles, CA 90089-2910, USA
| | - Ruben C Petreaca
- Program of Molecular and Computational Biology, University of Southern California, Los Angeles, CA 90089-2910, USA
- Department of Molecular Genetics, Ohio State University, Marion, OH 43302, USA
| | - Susan L Forsburg
- Program of Molecular and Computational Biology, University of Southern California, Los Angeles, CA 90089-2910, USA
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8
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Chen Z, Zehraoui E, Atanasoff-Kardjalieff AK, Strauss J, Studt L, Ponts N. Effect of H2A.Z deletion is rescued by compensatory mutations in Fusarium graminearum. PLoS Genet 2020; 16:e1009125. [PMID: 33091009 PMCID: PMC7608984 DOI: 10.1371/journal.pgen.1009125] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 11/03/2020] [Accepted: 09/21/2020] [Indexed: 12/31/2022] Open
Abstract
Fusarium head blight is a destructive disease of grains resulting in reduced yields and contamination of grains with mycotoxins worldwide; Fusarium graminearum is its major causal agent. Chromatin structure changes play key roles in regulating mycotoxin biosynthesis in filamentous fungi. Using a split-marker approach in three F. graminearum strains INRA156, INRA349 and INRA812 (PH-1), we knocked out the gene encoding H2A.Z, a ubiquitous histone variant reported to be involved in a diverse range of biological processes in yeast, plants and animals, but rarely studied in filamentous fungi. All ΔH2A.Z mutants exhibit defects in development including radial growth, sporulation, germination and sexual reproduction, but with varying degrees of severity between them. Heterogeneity of osmotic and oxidative stress response as well as mycotoxin production was observed in ΔH2A.Z strains. Adding-back wild-type H2A.Z in INRA349ΔH2A.Z could not rescue the phenotypes. Whole genome sequencing revealed that, although H2A.Z has been removed from the genome and the deletion cassette is inserted at H2A.Z locus only, mutations occur at other loci in each mutant regardless of the genetic background. Genes affected by these mutations encode proteins involved in chromatin remodeling, such as the helicase Swr1p or an essential subunit of the histone deacetylase Rpd3S, and one protein of unknown function. These observations suggest that H2A.Z and the genes affected by such mutations are part or the same genetic interaction network. Our results underline the genetic plasticity of F. graminearum facing detrimental gene perturbation. These findings suggest that intergenic suppressions rescue deleterious phenotypes in ΔH2A.Z strains, and that H2A.Z may be essential in F. graminearum. This assumption is further supported by the fact that H2A.Z deletion failed in another Fusarium spp., i.e., the rice pathogen Fusarium fujikuroi.
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Affiliation(s)
| | | | - Anna K. Atanasoff-Kardjalieff
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna (BOKU), Vienna, Austria
| | - Joseph Strauss
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna (BOKU), Vienna, Austria
| | - Lena Studt
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna (BOKU), Vienna, Austria
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9
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Nandy D, Rajam SM, Dutta D. A three layered histone epigenetics in breast cancer metastasis. Cell Biosci 2020; 10:52. [PMID: 32257110 PMCID: PMC7106732 DOI: 10.1186/s13578-020-00415-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 03/26/2020] [Indexed: 12/13/2022] Open
Abstract
Thanks to the advancement in science and technology and a significant number of cancer research programs being carried out throughout the world, the prevention, prognosis and treatment of breast cancer are improving with a positive and steady pace. However, a stern thoughtful attention is required for the metastatic breast cancer cases—the deadliest of all types of breast cancer, with a character of relapse even when treated. In an effort to explore the less travelled avenues, we summarize here studies underlying the aspects of histone epigenetics in breast cancer metastasis. Authoritative reviews on breast cancer epigenetics are already available; however, there is an urgent need to focus on the epigenetics involved in metastatic character of this cancer. Here we put forward a comprehensive review on how different layers of histone epigenetics comprising of histone chaperones, histone variants and histone modifications interplay to create breast cancer metastasis landscape. Finally, we propose a hypothesis of integrating histone-epigenetic factors as biomarkers that encompass different breast cancer subtypes and hence could be exploited as a target of larger population.
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Affiliation(s)
- Debparna Nandy
- Regenerative Biology Program, Rajiv Gandhi Centre for Biotechnology, Thycaud PO, Poojappura, Thiruvananthapuram, Kerala 695014 India
| | - Sruthy Manuraj Rajam
- Regenerative Biology Program, Rajiv Gandhi Centre for Biotechnology, Thycaud PO, Poojappura, Thiruvananthapuram, Kerala 695014 India
| | - Debasree Dutta
- Regenerative Biology Program, Rajiv Gandhi Centre for Biotechnology, Thycaud PO, Poojappura, Thiruvananthapuram, Kerala 695014 India
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10
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González-Medina A, Hidalgo E, Ayté J. Gcn5-mediated acetylation at MBF-regulated promoters induces the G1/S transcriptional wave. Nucleic Acids Res 2019; 47:8439-8451. [PMID: 31260531 PMCID: PMC6895280 DOI: 10.1093/nar/gkz561] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 06/17/2019] [Accepted: 06/21/2019] [Indexed: 11/26/2022] Open
Abstract
In fission yeast, MBF-dependent transcription is inactivated at the end of S phase through a negative feedback loop that involves the co-repressors, Yox1 and Nrm1. Although this repression system is well known, the molecular mechanisms involved in MBF activation remain largely unknown. Compacted chromatin constitutes a barrier to activators accessing promoters. Here, we show that chromatin regulation plays a key role in activating MBF-dependent transcription. Gcn5, a part of the SAGA complex, binds to MBF-regulated promoters through the MBF co-activator Rep2 in a cell cycle-dependent manner and in a reverse correlation to the binding of the MBF co-repressors, Nrm1 or Yox1. We propose that the co-repressors function as physical barriers to SAGA recruitment onto MBF promoters. We also show that Gcn5 acetylates specific lysine residues on histone H3 in a cell cycle-regulated manner. Furthermore, either in a gcn5 mutant or in a strain in which histone H3 is kept in an unacetylated form, MBF-dependent transcription is downregulated. In summary, Gcn5 is required for the full activation and correct timing of MBF-regulated gene transcription.
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Affiliation(s)
| | - Elena Hidalgo
- Oxidative Stress and Cell Cycle Group, Universitat Pompeu Fabra, Barcelona 08003, Spain
| | - José Ayté
- Oxidative Stress and Cell Cycle Group, Universitat Pompeu Fabra, Barcelona 08003, Spain
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11
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Yamada S, Kugou K, Ding DQ, Fujita Y, Hiraoka Y, Murakami H, Ohta K, Yamada T. The histone variant H2A.Z promotes initiation of meiotic recombination in fission yeast. Nucleic Acids Res 2019; 46:609-620. [PMID: 29145618 PMCID: PMC5778600 DOI: 10.1093/nar/gkx1110] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Accepted: 10/25/2017] [Indexed: 01/13/2023] Open
Abstract
Meiotic recombination is initiated by programmed formation of DNA double strand breaks (DSBs), which are mainly formed at recombination hotspots. Meiotic DSBs require multiple proteins including the conserved protein Spo11 and its cofactors, and are influenced by chromatin structure. For example, local chromatin around hotspots directly impacts DSB formation. Moreover, DSB is proposed to occur in a higher-order chromatin architecture termed 'axis-loop', in which many loops protrude from cohesin-enriched axis. However, still much remains unknown about how meiotic DSBs are generated in chromatin. Here, we show that the conserved histone H2A variant H2A.Z promotes meiotic DSB formation in fission yeast. Detailed investigation revealed that H2A.Z is neither enriched around hotspots nor axis sites, and that transcript levels of DSB-promoting factors were maintained without H2A.Z. Moreover, H2A.Z appeared to be dispensable for chromatin binding of meiotic cohesin. Instead, in H2A.Z-lacking mutants, multiple proteins involved in DSB formation, such as the fission yeast Spo11 homolog and its regulators, were less associated with chromatin. Remarkably, nuclei were more compact in the absence of H2A.Z. Based on these, we propose that fission yeast H2A.Z promotes meiotic DSB formation partly through modulating chromosome architecture to enhance interaction between DSB-related proteins and cohesin-loaded chromatin.
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Affiliation(s)
- Shintaro Yamada
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo 153-8902, Japan
| | - Kazuto Kugou
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo 153-8902, Japan
| | - Da-Qiao Ding
- Advanced ICT Research Institute Kobe, National Institute of Information and Communications Technology, Kobe 651-2492, Japan
| | - Yurika Fujita
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo 153-8902, Japan
| | - Yasushi Hiraoka
- Advanced ICT Research Institute Kobe, National Institute of Information and Communications Technology, Kobe 651-2492, Japan.,Graduate School of Frontier Biosciences, Osaka University, Suita 565-0871, Japan
| | - Hiroshi Murakami
- Department of Biological Sciences, Faculty of Science and Engineering, Chuo University, Tokyo 112-8551, Japan
| | - Kunihiro Ohta
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo 153-8902, Japan
| | - Takatomi Yamada
- Department of Biological Sciences, Faculty of Science and Engineering, Chuo University, Tokyo 112-8551, Japan
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12
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Giaimo BD, Ferrante F, Herchenröther A, Hake SB, Borggrefe T. The histone variant H2A.Z in gene regulation. Epigenetics Chromatin 2019; 12:37. [PMID: 31200754 PMCID: PMC6570943 DOI: 10.1186/s13072-019-0274-9] [Citation(s) in RCA: 170] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Accepted: 04/23/2019] [Indexed: 01/04/2023] Open
Abstract
The histone variant H2A.Z is involved in several processes such as transcriptional control, DNA repair, regulation of centromeric heterochromatin and, not surprisingly, is implicated in diseases such as cancer. Here, we review the recent developments on H2A.Z focusing on its role in transcriptional activation and repression. H2A.Z, as a replication-independent histone, has been studied in several model organisms and inducible mammalian model systems. Its loading machinery and several modifying enzymes have been recently identified, and some of the long-standing discrepancies in transcriptional activation and/or repression are about to be resolved. The buffering functions of H2A.Z, as supported by genome-wide localization and analyzed in several dynamic systems, are an excellent example of transcriptional control. Posttranslational modifications such as acetylation and ubiquitination of H2A.Z, as well as its specific binding partners, are in our view central players in the control of gene expression. Understanding the key-mechanisms in either turnover or stabilization of H2A.Z-containing nucleosomes as well as defining the H2A.Z interactome will pave the way for therapeutic applications in the future.
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Affiliation(s)
| | - Francesca Ferrante
- Institute of Biochemistry, University of Giessen, Friedrichstrasse 24, 35392, Giessen, Germany
| | - Andreas Herchenröther
- Institute for Genetics, University of Giessen, Heinrich-Buff-Ring 58-62, 35392, Giessen, Germany
| | - Sandra B Hake
- Institute for Genetics, University of Giessen, Heinrich-Buff-Ring 58-62, 35392, Giessen, Germany
| | - Tilman Borggrefe
- Institute of Biochemistry, University of Giessen, Friedrichstrasse 24, 35392, Giessen, Germany.
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13
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Noguchi C, Singh T, Ziegler MA, Peake JD, Khair L, Aza A, Nakamura TM, Noguchi E. The NuA4 acetyltransferase and histone H4 acetylation promote replication recovery after topoisomerase I-poisoning. Epigenetics Chromatin 2019; 12:24. [PMID: 30992049 PMCID: PMC6466672 DOI: 10.1186/s13072-019-0271-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Accepted: 04/10/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Histone acetylation plays an important role in DNA replication and repair because replicating chromatin is subject to dynamic changes in its structures. However, its precise mechanism remains elusive. In this report, we describe roles of the NuA4 acetyltransferase and histone H4 acetylation in replication fork protection in the fission yeast Schizosaccharomyces pombe. RESULTS Downregulation of NuA4 subunits renders cells highly sensitive to camptothecin, a compound that induces replication fork breakage. Defects in NuA4 function or mutations in histone H4 acetylation sites lead to impaired recovery of collapsed replication forks and elevated levels of Rad52 DNA repair foci, indicating the role of histone H4 acetylation in DNA replication and fork repair. We also show that Vid21 interacts with the Swi1-Swi3 replication fork protection complex and that Swi1 stabilizes Vid21 and promotes efficient histone H4 acetylation. Furthermore, our genetic analysis demonstrates that loss of Swi1 further sensitizes NuA4 and histone H4 mutant cells to replication fork breakage. CONCLUSION Considering that Swi1 plays a critical role in replication fork protection, our results indicate that NuA4 and histone H4 acetylation promote repair of broken DNA replication forks.
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Affiliation(s)
- Chiaki Noguchi
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, 245 N. 15th Street, Philadelphia, PA, 19102, USA
| | - Tanu Singh
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, 245 N. 15th Street, Philadelphia, PA, 19102, USA.,Fox Chase Cancer Center, Philadelphia, USA
| | - Melissa A Ziegler
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, 245 N. 15th Street, Philadelphia, PA, 19102, USA
| | - Jasmine D Peake
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, 245 N. 15th Street, Philadelphia, PA, 19102, USA
| | - Lyne Khair
- Department of Biochemistry and Molecular Genetics, University of Illinois at Chicago, Chicago, IL, 60607, USA.,University of Massachusetts Medical School, Worcester, USA
| | - Ana Aza
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, 245 N. 15th Street, Philadelphia, PA, 19102, USA
| | - Toru M Nakamura
- Department of Biochemistry and Molecular Genetics, University of Illinois at Chicago, Chicago, IL, 60607, USA
| | - Eishi Noguchi
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, 245 N. 15th Street, Philadelphia, PA, 19102, USA.
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14
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Hocquet C, Robellet X, Modolo L, Sun XM, Burny C, Cuylen-Haering S, Toselli E, Clauder-Münster S, Steinmetz L, Haering CH, Marguerat S, Bernard P. Condensin controls cellular RNA levels through the accurate segregation of chromosomes instead of directly regulating transcription. eLife 2018; 7:38517. [PMID: 30230473 PMCID: PMC6173581 DOI: 10.7554/elife.38517] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2018] [Accepted: 09/18/2018] [Indexed: 12/15/2022] Open
Abstract
Condensins are genome organisers that shape chromosomes and promote their accurate transmission. Several studies have also implicated condensins in gene expression, although any mechanisms have remained enigmatic. Here, we report on the role of condensin in gene expression in fission and budding yeasts. In contrast to previous studies, we provide compelling evidence that condensin plays no direct role in the maintenance of the transcriptome, neither during interphase nor during mitosis. We further show that the changes in gene expression in post-mitotic fission yeast cells that result from condensin inactivation are largely a consequence of chromosome missegregation during anaphase, which notably depletes the RNA-exosome from daughter cells. Crucially, preventing karyotype abnormalities in daughter cells restores a normal transcriptome despite condensin inactivation. Thus, chromosome instability, rather than a direct role of condensin in the transcription process, changes gene expression. This knowledge challenges the concept of gene regulation by canonical condensin complexes.
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Affiliation(s)
- Clémence Hocquet
- CNRS Laboratory of Biology and Modelling of the Cell, Lyon, France.,Université de Lyon, ENSL, UCBL, Lyon, France
| | - Xavier Robellet
- CNRS Laboratory of Biology and Modelling of the Cell, Lyon, France.,Université de Lyon, ENSL, UCBL, Lyon, France
| | - Laurent Modolo
- CNRS Laboratory of Biology and Modelling of the Cell, Lyon, France.,Université de Lyon, ENSL, UCBL, Lyon, France
| | - Xi-Ming Sun
- MRC London Institute of Medical Sciences, London, United Kingdom.,Institute of Clinical Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Claire Burny
- CNRS Laboratory of Biology and Modelling of the Cell, Lyon, France.,Université de Lyon, ENSL, UCBL, Lyon, France
| | - Sara Cuylen-Haering
- Cell Biology and Biophysics Unit, Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Esther Toselli
- CNRS Laboratory of Biology and Modelling of the Cell, Lyon, France.,Université de Lyon, ENSL, UCBL, Lyon, France
| | | | - Lars Steinmetz
- Genome Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Christian H Haering
- Cell Biology and Biophysics Unit, Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Samuel Marguerat
- MRC London Institute of Medical Sciences, London, United Kingdom.,Institute of Clinical Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Pascal Bernard
- CNRS Laboratory of Biology and Modelling of the Cell, Lyon, France.,Université de Lyon, ENSL, UCBL, Lyon, France
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15
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Knezevic I, González-Medina A, Gaspa L, Hidalgo E, Ayté J. The INO80 complex activates the transcription of S-phase genes in a cell cycle-regulated manner. FEBS J 2018; 285:3870-3881. [PMID: 30134042 DOI: 10.1111/febs.14640] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 07/30/2018] [Accepted: 08/20/2018] [Indexed: 12/13/2022]
Abstract
Chromatin structure is an essential factor in the proper regulation of DNA repair, DNA replication and transcription. The INO80 complex and the SWR complex have been shown to play a fundamental role in transcription regulation through remodeling chromatin at specific genes and loci. Here, we report that the Schizosaccharomyces pombe INO80 complex physically interacts with the mlui-binding factor (MBF) complex. Furthermore, we are able to detect the INO80 complex in MBF-regulated promoters. Binding of INO80 to these genes is cell cycle regulated, with a maximum binding preceding their transcription and accumulation of their mRNAs. In fact, the INO80 complex is required to fully and timely activate the transcription of these genes. We also show that the accumulation of acetylated H2A.Z at the +1 nucleosome is cell cycle regulated. Cells in which H2A.Z acetylation is abolished still have some cell cycle-regulated transcription of MBF-dependent genes, although to a much lesser extent.
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Affiliation(s)
- Iva Knezevic
- Departament de Ciències, Experimentals i de la Salut, Universitat Pompeu Fabra, Barcelona, Spain
| | - Alberto González-Medina
- Departament de Ciències, Experimentals i de la Salut, Universitat Pompeu Fabra, Barcelona, Spain
| | - Laura Gaspa
- Departament de Ciències, Experimentals i de la Salut, Universitat Pompeu Fabra, Barcelona, Spain
| | - Elena Hidalgo
- Departament de Ciències, Experimentals i de la Salut, Universitat Pompeu Fabra, Barcelona, Spain
| | - José Ayté
- Departament de Ciències, Experimentals i de la Salut, Universitat Pompeu Fabra, Barcelona, Spain
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16
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Maya Miles D, Peñate X, Sanmartín Olmo T, Jourquin F, Muñoz Centeno MC, Mendoza M, Simon MN, Chavez S, Geli V. High levels of histones promote whole-genome-duplications and trigger a Swe1 WEE1-dependent phosphorylation of Cdc28 CDK1. eLife 2018; 7:35337. [PMID: 29580382 PMCID: PMC5871333 DOI: 10.7554/elife.35337] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 03/05/2018] [Indexed: 12/13/2022] Open
Abstract
Whole-genome duplications (WGDs) have played a central role in the evolution of genomes and constitute an important source of genome instability in cancer. Here, we show in Saccharomyces cerevisiae that abnormal accumulations of histones are sufficient to induce WGDs. Our results link these WGDs to a reduced incorporation of the histone variant H2A.Z to chromatin. Moreover, we show that high levels of histones promote Swe1WEE1 stabilisation thereby triggering the phosphorylation and inhibition of Cdc28CDK1 through a mechanism different of the canonical DNA damage response. Our results link high levels of histones to a specific type of genome instability that is quite frequently observed in cancer and uncovers a new mechanism that might be able to respond to high levels of histones.
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Affiliation(s)
- Douglas Maya Miles
- Marseille Cancer Research Center (CRCM), U1068 Inserm, UMR7258 CNRS, Aix-Marseille Université, Institut Paoli-Calmettes, Equipe Labellisée Ligue, Marseille, France
| | - Xenia Peñate
- Instituto de Biomedicina de Sevilla, Hospital Virgen del Rocío-CSIC-Universidad de Sevilla, Sevilla, Spain
| | - Trinidad Sanmartín Olmo
- Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Barcelona, Spain.,Universitat Pompeu Fabra, Barcelona, Spain
| | - Frederic Jourquin
- Marseille Cancer Research Center (CRCM), U1068 Inserm, UMR7258 CNRS, Aix-Marseille Université, Institut Paoli-Calmettes, Equipe Labellisée Ligue, Marseille, France
| | - Maria Cruz Muñoz Centeno
- Instituto de Biomedicina de Sevilla, Hospital Virgen del Rocío-CSIC-Universidad de Sevilla, Sevilla, Spain
| | - Manuel Mendoza
- Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Barcelona, Spain.,Universitat Pompeu Fabra, Barcelona, Spain
| | - Marie-Noelle Simon
- Marseille Cancer Research Center (CRCM), U1068 Inserm, UMR7258 CNRS, Aix-Marseille Université, Institut Paoli-Calmettes, Equipe Labellisée Ligue, Marseille, France
| | - Sebastian Chavez
- Instituto de Biomedicina de Sevilla, Hospital Virgen del Rocío-CSIC-Universidad de Sevilla, Sevilla, Spain
| | - Vincent Geli
- Marseille Cancer Research Center (CRCM), U1068 Inserm, UMR7258 CNRS, Aix-Marseille Université, Institut Paoli-Calmettes, Equipe Labellisée Ligue, Marseille, France
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17
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Yamada S, Kugou K, Ding DQ, Fujita Y, Hiraoka Y, Murakami H, Ohta K, Yamada T. The conserved histone variant H2A.Z illuminates meiotic recombination initiation. Curr Genet 2018; 64:1015-1019. [DOI: 10.1007/s00294-018-0825-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Revised: 03/13/2018] [Accepted: 03/13/2018] [Indexed: 12/30/2022]
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18
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Saettone A, Garg J, Lambert JP, Nabeel-Shah S, Ponce M, Burtch A, Thuppu Mudalige C, Gingras AC, Pearlman RE, Fillingham J. The bromodomain-containing protein Ibd1 links multiple chromatin-related protein complexes to highly expressed genes in Tetrahymena thermophila. Epigenetics Chromatin 2018. [PMID: 29523178 PMCID: PMC5844071 DOI: 10.1186/s13072-018-0180-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Background The chromatin remodelers of the SWI/SNF family are critical transcriptional regulators. Recognition of lysine acetylation through a bromodomain (BRD) component is key to SWI/SNF function; in most eukaryotes, this function is attributed to SNF2/Brg1. Results Using affinity purification coupled to mass spectrometry (AP–MS) we identified members of a SWI/SNF complex (SWI/SNFTt) in Tetrahymena thermophila. SWI/SNFTt is composed of 11 proteins, Snf5Tt, Swi1Tt, Swi3Tt, Snf12Tt, Brg1Tt, two proteins with potential chromatin-interacting domains and four proteins without orthologs to SWI/SNF proteins in yeast or mammals. SWI/SNFTt subunits localize exclusively to the transcriptionally active macronucleus during growth and development, consistent with a role in transcription. While Tetrahymena Brg1 does not contain a BRD, our AP–MS results identified a BRD-containing SWI/SNFTt component, Ibd1 that associates with SWI/SNFTt during growth but not development. AP–MS analysis of epitope-tagged Ibd1 revealed it to be a subunit of several additional protein complexes, including putative SWRTt, and SAGATt complexes as well as a putative H3K4-specific histone methyl transferase complex. Recombinant Ibd1 recognizes acetyl-lysine marks on histones correlated with active transcription. Consistent with our AP–MS and histone array data suggesting a role in regulation of gene expression, ChIP-Seq analysis of Ibd1 indicated that it primarily binds near promoters and within gene bodies of highly expressed genes during growth. Conclusions Our results suggest that through recognizing specific histones marks, Ibd1 targets active chromatin regions of highly expressed genes in Tetrahymena where it subsequently might coordinate the recruitment of several chromatin-remodeling complexes to regulate the transcriptional landscape of vegetatively growing Tetrahymena cells. Electronic supplementary material The online version of this article (10.1186/s13072-018-0180-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Alejandro Saettone
- Department of Chemistry and Biology, Ryerson University, 350 Victoria St., Toronto, M5B 2K3, Canada
| | - Jyoti Garg
- Department of Biology, York University, 4700 Keele St., Toronto, M3J 1P3, Canada
| | - Jean-Philippe Lambert
- Lunenfeld-Tanenbaum Research Institute at Mount Sinai Hospital, Toronto, M5G 1X5, Canada.,Department of Molecular Medicine, Université Laval, Quebec, Canada.,Centre Hospitalier Universitaire de Québec Research Center, CHUL, 2705 Boulevard Laurier, Quebec, G1V 4G2, Canada
| | - Syed Nabeel-Shah
- Department of Chemistry and Biology, Ryerson University, 350 Victoria St., Toronto, M5B 2K3, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, M5S 1A8, Canada
| | - Marcelo Ponce
- SciNet HPC Consortium, University of Toronto, 661 University Ave, Suite 1140, Toronto, M5G 1M1, Canada
| | - Alyson Burtch
- Department of Chemistry and Biology, Ryerson University, 350 Victoria St., Toronto, M5B 2K3, Canada
| | - Cristina Thuppu Mudalige
- Department of Chemistry and Biology, Ryerson University, 350 Victoria St., Toronto, M5B 2K3, Canada
| | - Anne-Claude Gingras
- Lunenfeld-Tanenbaum Research Institute at Mount Sinai Hospital, Toronto, M5G 1X5, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, M5S 1A8, Canada
| | - Ronald E Pearlman
- Department of Biology, York University, 4700 Keele St., Toronto, M3J 1P3, Canada
| | - Jeffrey Fillingham
- Department of Chemistry and Biology, Ryerson University, 350 Victoria St., Toronto, M5B 2K3, Canada.
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19
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Roguev A, Ryan CJ, Hartsuiker E, Krogan NJ. High-Throughput Quantitative Genetic Interaction Mapping in the Fission Yeast Schizosaccharomyces pombe. Cold Spring Harb Protoc 2018; 2018:pdb.top079905. [PMID: 28733404 DOI: 10.1101/pdb.top079905] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Epistasis mapping, in which the phenotype that emerges from combining pairs of mutations is measured quantitatively, is a powerful tool for unbiased study of gene function. When performed at a large scale, this approach has been used to assign function to previously uncharacterized genes, define functional modules and pathways, and study their cross talk. These experiments rely heavily on methods for rapid sampling of binary combinations of mutant alleles by systematic generation of a series of double mutants. Epistasis mapping technologies now exist in various model systems. Here we provide an overview of different epistasis mapping technologies, including the pombe epistasis mapper (PEM) system designed for the collection of quantitative genetic interaction data in fission yeast Schizosaccharomyces pombe Comprising a series of high-throughput selection steps for generation and characterization of double mutants, the PEM system has provided insight into a wide range of biological processes as well as facilitated evolutionary analysis of genetic interactomes across different species.
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Affiliation(s)
- Assen Roguev
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, California 94518
| | - Colm J Ryan
- Systems Biology Ireland, University College Dublin, Belfield, Dublin 4, Ireland
| | - Edgar Hartsuiker
- North West Cancer Research Institute, Bangor University, Bangor LL57 2UW, United Kingdom
| | - Nevan J Krogan
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, California 94518
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20
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Abstract
The three-dimensional (3D) genome structure is highly ordered by a hierarchy of organizing events ranging from enhancer-promoter or gene-gene contacts to chromosomal territorial arrangement. It is becoming clear that the cohesin and condensin complexes are key molecular machines that organize the 3D genome structure. These complexes are highly conserved from simple systems, e.g., yeast cells, to the much more complex human system. Therefore, knowledge from the budding and fission yeast systems illuminates highly conserved molecular mechanisms of how cohesin and condensin establish the functional 3D genome structures. Here I discuss how these complexes are recruited across the yeast genomes, mediate distinct genome-organizing events such as gene contacts and topological domain formation, and participate in important nuclear activities including transcriptional regulation and chromosomal dynamics.
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Affiliation(s)
- Ken-Ichi Noma
- Gene Expression and Regulation Program, The Wistar Institute, Philadelphia, Pennsylvania 19104, USA;
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21
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Nissen KE, Homer CM, Ryan CJ, Shales M, Krogan NJ, Patrick KL, Guthrie C. The histone variant H2A.Z promotes splicing of weak introns. Genes Dev 2017; 31:688-701. [PMID: 28446597 PMCID: PMC5411709 DOI: 10.1101/gad.295287.116] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Accepted: 03/22/2017] [Indexed: 12/12/2022]
Abstract
In this study, Nissen et al. investigated the function of the highly conserved histone variant H2A.Z in pre-mRNA splicing using the intron-rich model yeast S. pombe. The findings suggest that H2A.Z occupancy promotes cotranscriptional splicing of suboptimal introns that may otherwise be discarded via proofreading ATPases. Multiple lines of evidence implicate chromatin in the regulation of premessenger RNA (pre-mRNA) splicing. However, the influence of chromatin factors on cotranscriptional splice site usage remains unclear. Here we investigated the function of the highly conserved histone variant H2A.Z in pre-mRNA splicing using the intron-rich model yeast Schizosaccharomyces pombe. Using epistatic miniarray profiles (EMAPs) to survey the genetic interaction landscape of the Swr1 nucleosome remodeling complex, which deposits H2A.Z, we uncovered evidence for functional interactions with components of the spliceosome. In support of these genetic connections, splicing-specific microarrays show that H2A.Z and the Swr1 ATPase are required during temperature stress for the efficient splicing of a subset of introns. Notably, affected introns are enriched for H2A.Z occupancy and more likely to contain nonconsensus splice sites. To test the significance of the latter correlation, we mutated the splice sites in an affected intron to consensus and found that this suppressed the requirement for H2A.Z in splicing of that intron. These data suggest that H2A.Z occupancy promotes cotranscriptional splicing of suboptimal introns that may otherwise be discarded via proofreading ATPases. Consistent with this model, we show that overexpression of splicing ATPase Prp16 suppresses both the growth and splicing defects seen in the absence of H2A.Z.
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Affiliation(s)
- Kelly E Nissen
- Department of Biochemistry and Biophysics, University of California at San Francisco, San Francisco 94158, California, USA
| | - Christina M Homer
- Department of Biochemistry and Biophysics, University of California at San Francisco, San Francisco 94158, California, USA
| | - Colm J Ryan
- Systems Biology Ireland, University College Dublin, Belfield, Dublin 4, Ireland
| | - Michael Shales
- Department of Cellular and Molecular Pharmacology, University of California at San Francisco, San Francisco 94158, California, USA.,California Institute for Quantitative Biosciences (QB3), San Francisco 94158, California, USA
| | - Nevan J Krogan
- Department of Cellular and Molecular Pharmacology, University of California at San Francisco, San Francisco 94158, California, USA.,California Institute for Quantitative Biosciences (QB3), San Francisco 94158, California, USA.,J. David Gladstone Institutes, San Francisco 94158, California, USA
| | - Kristin L Patrick
- Department of Biochemistry and Biophysics, University of California at San Francisco, San Francisco 94158, California, USA.,Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, Bryan, Texas 77807, USA
| | - Christine Guthrie
- Department of Biochemistry and Biophysics, University of California at San Francisco, San Francisco 94158, California, USA
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22
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Messina G, Atterrato MT, Prozzillo Y, Piacentini L, Losada A, Dimitri P. The human Cranio Facial Development Protein 1 (Cfdp1) gene encodes a protein required for the maintenance of higher-order chromatin organization. Sci Rep 2017; 7:45022. [PMID: 28367969 PMCID: PMC5377257 DOI: 10.1038/srep45022] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 02/20/2017] [Indexed: 12/26/2022] Open
Abstract
The human Cranio Facial Development Protein 1 (Cfdp1) gene maps to chromosome 16q22.2-q22.3 and encodes the CFDP1 protein, which belongs to the evolutionarily conserved Bucentaur (BCNT) family. Craniofacial malformations are developmental disorders of particular biomedical and clinical interest, because they represent the main cause of infant mortality and disability in humans, thus it is important to understand the cellular functions and mechanism of action of the CFDP1 protein. We have carried out a multi-disciplinary study, combining cell biology, reverse genetics and biochemistry, to provide the first in vivo characterization of CFDP1 protein functions in human cells. We show that CFDP1 binds to chromatin and interacts with subunits of the SRCAP chromatin remodeling complex. An RNAi-mediated depletion of CFDP1 in HeLa cells affects chromosome organization, SMC2 condensin recruitment and cell cycle progression. Our findings provide new insight into the chromatin functions and mechanisms of the CFDP1 protein and contribute to our understanding of the link between epigenetic regulation and the onset of human complex developmental disorders.
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Affiliation(s)
- Giovanni Messina
- Istituto Pasteur Italia-Fondazione Cenci Bolognetti and Dipartimento di Biologia e Biotecnologie "Charles Darwin", Sapienza Università di Roma, Italy.,Dipartimento di Biologia e Biotecnologie "Charles Darwin" Sapienza Università di Roma, Roma, Italy
| | - Maria Teresa Atterrato
- Istituto Pasteur Italia-Fondazione Cenci Bolognetti and Dipartimento di Biologia e Biotecnologie "Charles Darwin", Sapienza Università di Roma, Italy.,Dipartimento di Biologia e Biotecnologie "Charles Darwin" Sapienza Università di Roma, Roma, Italy
| | - Yuri Prozzillo
- Istituto Pasteur Italia-Fondazione Cenci Bolognetti and Dipartimento di Biologia e Biotecnologie "Charles Darwin", Sapienza Università di Roma, Italy.,Dipartimento di Biologia e Biotecnologie "Charles Darwin" Sapienza Università di Roma, Roma, Italy
| | - Lucia Piacentini
- Dipartimento di Biologia e Biotecnologie "Charles Darwin" Sapienza Università di Roma, Roma, Italy
| | | | - Patrizio Dimitri
- Istituto Pasteur Italia-Fondazione Cenci Bolognetti and Dipartimento di Biologia e Biotecnologie "Charles Darwin", Sapienza Università di Roma, Italy.,Dipartimento di Biologia e Biotecnologie "Charles Darwin" Sapienza Università di Roma, Roma, Italy
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23
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Abstract
The fidelity of mitosis is essential for life, and successful completion of this process relies on drastic changes in chromosome organization at the onset of nuclear division. The mechanisms that govern chromosome compaction at every cell division cycle are still far from full comprehension, yet recent studies provide novel insights into this problem, challenging classical views on mitotic chromosome assembly. Here, we briefly introduce various models for chromosome assembly and known factors involved in the condensation process (e.g. condensin complexes and topoisomerase II). We will then focus on a few selected studies that have recently brought novel insights into the mysterious way chromosomes are condensed during nuclear division.
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Affiliation(s)
- Ewa Piskadlo
- Instituto Gulbenkian de Ciência, Rua da Quinta Grande 6, Oeiras, 2780-156 , Portugal
| | - Raquel A Oliveira
- Instituto Gulbenkian de Ciência, Rua da Quinta Grande 6, Oeiras, 2780-156 , Portugal
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24
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Gadaleta MC, Das MM, Tanizawa H, Chang YT, Noma KI, Nakamura TM, Noguchi E. Swi1Timeless Prevents Repeat Instability at Fission Yeast Telomeres. PLoS Genet 2016; 12:e1005943. [PMID: 26990647 PMCID: PMC4798670 DOI: 10.1371/journal.pgen.1005943] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 02/25/2016] [Indexed: 01/09/2023] Open
Abstract
Genomic instability associated with DNA replication stress is linked to cancer and genetic pathologies in humans. If not properly regulated, replication stress, such as fork stalling and collapse, can be induced at natural replication impediments present throughout the genome. The fork protection complex (FPC) is thought to play a critical role in stabilizing stalled replication forks at several known replication barriers including eukaryotic rDNA genes and the fission yeast mating-type locus. However, little is known about the role of the FPC at other natural impediments including telomeres. Telomeres are considered to be difficult to replicate due to the presence of repetitive GT-rich sequences and telomere-binding proteins. However, the regulatory mechanism that ensures telomere replication is not fully understood. Here, we report the role of the fission yeast Swi1Timeless, a subunit of the FPC, in telomere replication. Loss of Swi1 causes telomere shortening in a telomerase-independent manner. Our epistasis analyses suggest that heterochromatin and telomere-binding proteins are not major impediments for telomere replication in the absence of Swi1. Instead, repetitive DNA sequences impair telomere integrity in swi1Δ mutant cells, leading to the loss of repeat DNA. In the absence of Swi1, telomere shortening is accompanied with an increased recruitment of Rad52 recombinase and more frequent amplification of telomere/subtelomeres, reminiscent of tumor cells that utilize the alternative lengthening of telomeres pathway (ALT) to maintain telomeres. These results suggest that Swi1 ensures telomere replication by suppressing recombination and repeat instability at telomeres. Our studies may also be relevant in understanding the potential role of Swi1Timeless in regulation of telomere stability in cancer cells. In every round of the cell cycle, cells must accurately replicate their full genetic information. This process is highly regulated, as defects during DNA replication cause genomic instability, leading to various genetic disorders including cancers. To thwart these problems, cells carry an array of complex mechanisms to deal with various obstacles found across the genome that can hamper DNA replication and cause DNA damage. Understanding how these mechanisms are regulated and orchestrated is of paramount importance in the field. In this report, we describe how Swi1, a Timeless-related protein in fission yeast, regulates efficient replication of telomeres, which are considered to be difficult to replicate due to the presence of repetitive DNA and telomere-binding proteins. We show that Swi1 prevents telomere damage and maintains telomere length by protecting integrity of telomeric repeats. Swi1-mediated telomere maintenance is independent of telomerase activity, and loss of Swi1 causes hyper-activation of recombination-based telomere maintenance, which generates heterogeneous telomeres. Similar telomerase-independent and recombination-dependent mechanism is utilized by approximately 15% of human cancers, linking telomere replication defects with cancer development. Thus, our study may be relevant in understanding the role of telomere replication defects in the development of cancers in humans.
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Affiliation(s)
- Mariana C. Gadaleta
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Mukund M. Das
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Hideki Tanizawa
- Gene Expression and Regulation Program, The Wistar Institute, Philadelphia, Pennsylvania, United States of America
| | - Ya-Ting Chang
- Department of Biochemistry and Molecular Genetics, College of Medicine, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Ken-ichi Noma
- Gene Expression and Regulation Program, The Wistar Institute, Philadelphia, Pennsylvania, United States of America
| | - Toru M. Nakamura
- Department of Biochemistry and Molecular Genetics, College of Medicine, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Eishi Noguchi
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, Pennsylvania, United States of America
- * E-mail:
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Kusakabe M, Oku H, Matsuda R, Hori T, Muto A, Igarashi K, Fukagawa T, Harata M. Genetic complementation analysis showed distinct contributions of the N-terminal tail of H2A.Z to epigenetic regulations. Genes Cells 2016; 21:122-35. [DOI: 10.1111/gtc.12327] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Accepted: 11/18/2015] [Indexed: 12/30/2022]
Affiliation(s)
- Masayuki Kusakabe
- Laboratory of Molecular Biology; Graduate School of Agricultural Science; Tohoku University; Tsutsumidori-amamiyamachi 1-1 Aoba-ku Sendai 981-8555 Japan
| | - Hiroyuki Oku
- Laboratory of Molecular Biology; Graduate School of Agricultural Science; Tohoku University; Tsutsumidori-amamiyamachi 1-1 Aoba-ku Sendai 981-8555 Japan
| | - Ryo Matsuda
- Laboratory of Molecular Biology; Graduate School of Agricultural Science; Tohoku University; Tsutsumidori-amamiyamachi 1-1 Aoba-ku Sendai 981-8555 Japan
| | - Tetsuya Hori
- Graduate School of Frontier Biosciences; Osaka University; Yamadaoka 1-3 Suita Osaka 565-0871 Japan
| | - Akihiko Muto
- Department of Biochemistry; Graduate School of Medicine; Tohoku University; Seiryo-cho 2-1 Aoba-ku Sendai 980-8575 Japan
| | - Kazuhiko Igarashi
- Department of Biochemistry; Graduate School of Medicine; Tohoku University; Seiryo-cho 2-1 Aoba-ku Sendai 980-8575 Japan
| | - Tatsuo Fukagawa
- Graduate School of Frontier Biosciences; Osaka University; Yamadaoka 1-3 Suita Osaka 565-0871 Japan
| | - Masahiko Harata
- Laboratory of Molecular Biology; Graduate School of Agricultural Science; Tohoku University; Tsutsumidori-amamiyamachi 1-1 Aoba-ku Sendai 981-8555 Japan
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26
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Vernì F, Cenci G. The Drosophila histone variant H2A.V works in concert with HP1 to promote kinetochore-driven microtubule formation. Cell Cycle 2015; 14:577-88. [PMID: 25591068 DOI: 10.4161/15384101.2014.991176] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Unlike other organisms that have evolved distinct H2A variants for different functions, Drosophila melanogaster has just one variant which is capable of filling many roles. This protein, H2A.V, combines the features of the conserved variants H2A.Z and H2A.X in transcriptional control/heterochromatin assembly and DNA damage response, respectively. Here we show that mutations in the gene encoding H2A.V affect chromatin compaction and perturb chromosome segregation in Drosophila mitotic cells. A microtubule (MT) regrowth assay after cold exposure revealed that loss of H2A.V impairs the formation of kinetochore-driven (k) fibers, which can account for defects in chromosome segregation. All defects are rescued by a transgene encoding H2A.V that lacks the H2A.X function in the DNA damage response, suggesting that the H2A.Z (but not H2A.X) functionality of H2A.V is required for chromosome segregation. We also found that loss of H2A.V weakens HP1 localization, specifically at the pericentric heterochromatin of metaphase chromosomes. Interestingly, loss of HP1 yielded not only telomeric fusions but also mitotic defects similar to those seen in H2A.V null mutants, suggesting a role for HP1 in chromosome segregation. We also show that H2A.V precipitates HP1 from larval brain extracts indicating that both proteins are part of the same complex. Moreover, we found that the overexpression of HP1 rescues chromosome missegregation and defects in the kinetochore-driven k-fiber regrowth of H2A.V mutants indicating that both phenotypes are influenced by unbalanced levels of HP1. Collectively, our results suggest that H2A.V and HP1 work in concert to ensure kinetochore-driven MT growth.
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Affiliation(s)
- Fiammetta Vernì
- a Dipartimento di Biologia e Biotecnologie "C. Darwin" ; Sapienza Università di Roma ; Roma , Italy
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Escape from Mitotic Arrest: An Unexpected Connection Between Microtubule Dynamics and Epigenetic Regulation of Centromeric Chromatin in Schizosaccharomyces pombe. Genetics 2015; 201:1467-78. [PMID: 26510788 DOI: 10.1534/genetics.115.181792] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Accepted: 10/23/2015] [Indexed: 01/02/2023] Open
Abstract
Accurate chromosome segregation is necessary to ensure genomic integrity. Segregation depends on the proper functioning of the centromere, kinetochore, and mitotic spindle microtubules and is monitored by the spindle assembly checkpoint (SAC). In the fission yeast Schizosaccharomyces pombe, defects in Dis1, a microtubule-associated protein that influences microtubule dynamics, lead to mitotic arrest as a result of an active SAC and consequent failure to grow at low temperature. In a mutant dis1 background (dis1-288), loss of function of Msc1, a fission yeast homolog of the KDM5 family of proteins, suppresses the growth defect and promotes normal mitosis. Genetic analysis implicates a histone deacetylase (HDAC)-linked pathway in suppression because HDAC mutants clr6-1, clr3∆, and sir2∆, though not hos2∆, also promote normal mitosis in the dis1-288 mutant. Suppression of the dis phenotype through loss of msc1 function requires the spindle checkpoint protein Mad2 and is limited by the presence of the heterochromatin-associated HP1 protein homolog Swi6. We speculate that alterations in histone acetylation promote a centromeric chromatin environment that compensates for compromised dis1 function by allowing for successful kinetochore-microtubule interactions that can satisfy the SAC. In cells arrested in mitosis by mutation of dis1, loss of function of epigenetic determinants such as Msc1 or specific HDACs can promote cell survival. Because the KDM5 family of proteins has been implicated in human cancers, an appreciation of the potential role of this family of proteins in chromosome segregation is warranted.
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Melters DP, Nye J, Zhao H, Dalal Y. Chromatin Dynamics in Vivo: A Game of Musical Chairs. Genes (Basel) 2015; 6:751-76. [PMID: 26262644 PMCID: PMC4584328 DOI: 10.3390/genes6030751] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Revised: 07/17/2015] [Accepted: 07/28/2015] [Indexed: 01/30/2023] Open
Abstract
Histones are a major component of chromatin, the nucleoprotein complex fundamental to regulating transcription, facilitating cell division, and maintaining genome integrity in almost all eukaryotes. In addition to canonical, replication-dependent histones, replication-independent histone variants exist in most eukaryotes. In recent years, steady progress has been made in understanding how histone variants assemble, their involvement in development, mitosis, transcription, and genome repair. In this review, we will focus on the localization of the major histone variants H3.3, CENP-A, H2A.Z, and macroH2A, as well as how these variants have evolved, their structural differences, and their functional significance in vivo.
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Affiliation(s)
- Daniël P Melters
- Chromatin Structure and Epigenetics Mechanisms Unit, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 41 Library Drive, Bethesda, MD 20892, USA.
| | - Jonathan Nye
- Chromatin Structure and Epigenetics Mechanisms Unit, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 41 Library Drive, Bethesda, MD 20892, USA.
| | - Haiqing Zhao
- Chromatin Structure and Epigenetics Mechanisms Unit, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 41 Library Drive, Bethesda, MD 20892, USA.
- Biophysics Graduate Program, University of Maryland, College Park, MD 20742, USA.
| | - Yamini Dalal
- Chromatin Structure and Epigenetics Mechanisms Unit, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 41 Library Drive, Bethesda, MD 20892, USA.
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29
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Abstract
Faithful DNA replication is a prerequisite for cell proliferation. Several cytological studies have shown that chromosome structures alter in the S-phase of the cell cycle. However, the molecular mechanisms behind the alteration of chromosome structures associated with DNA replication have not been elucidated. Here, we investigated chromatin structures and acetylation of specific histone residues during DNA replication using the meiotic nucleus of the fission yeast Schizosaccharomyces pombe. The S. pombe meiotic nucleus provides a unique opportunity for measuring the levels of compaction of chromatin along the chromosome in a defined orientation. By direct measurement of chromatin compaction in living cells, we demonstrated that decompaction of chromatin occurs during meiotic DNA replication. This chromatin decompaction was suppressed by depletion of histone acetyltransferase Mst1 or by arginine substitution of specific lysine residues (K8 and K12) of histone H4. These results suggest that acetylation of histone H4 residues K8 and K12 plays a critical role in loosening chromatin structures during DNA replication.
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30
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Allshire RC, Ekwall K. Epigenetic Regulation of Chromatin States in Schizosaccharomyces pombe. Cold Spring Harb Perspect Biol 2015; 7:a018770. [PMID: 26134317 DOI: 10.1101/cshperspect.a018770] [Citation(s) in RCA: 126] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
This article discusses the advances made in epigenetic research using the model organism fission yeast Schizosaccharomyces pombe. S. pombe has been used for epigenetic research since the discovery of position effect variegation (PEV). This is a phenomenon in which a transgene inserted within heterochromatin is variably expressed, but can be stably inherited in subsequent cell generations. PEV occurs at centromeres, telomeres, ribosomal DNA (rDNA) loci, and mating-type regions of S. pombe chromosomes. Heterochromatin assembly in these regions requires enzymes that modify histones and the RNA interference (RNAi) machinery. One of the key histone-modifying enzymes is the lysine methyltransferase Clr4, which methylates histone H3 on lysine 9 (H3K9), a classic hallmark of heterochromatin. The kinetochore is assembled on specialized chromatin in which histone H3 is replaced by the variant CENP-A. Studies in fission yeast have contributed to our understanding of the establishment and maintenance of CENP-A chromatin and the epigenetic activation and inactivation of centromeres.
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Affiliation(s)
- Robin C Allshire
- Wellcome Trust Centre for Cell Biology, The University of Edinburgh, Edinburgh EH9 3JR, Scotland, United Kingdom
| | - Karl Ekwall
- Department of Biosciences and Nutrition, Karolinska Institutet, Center for Biosciences, NOVUM, S-141 83, Huddinge, Sweden
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31
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Overlapping Functions between SWR1 Deletion and H3K56 Acetylation in Candida albicans. EUKARYOTIC CELL 2015; 14:578-87. [PMID: 25862154 DOI: 10.1128/ec.00002-15] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Accepted: 04/03/2015] [Indexed: 11/20/2022]
Abstract
Nucleosome destabilization by histone variants and modifications has been implicated in the epigenetic regulation of gene expression, with the histone variant H2A.Z and acetylation of H3K56 (H3K56ac) being two examples. Here we find that deletion of SWR1, the major subunit of the SWR1 complex depositing H2A.Z into chromatin in exchange for H2A, promotes epigenetic white-opaque switching in Candida albicans. We demonstrate through nucleosome mapping that SWR1 is required for proper nucleosome positioning on the promoter of WOR1, the master regulator of switching, and that its effects differ in white and opaque cells. Furthermore, we find that H2A.Z is enriched adjacent to nucleosome-free regions at the WOR1 promoter in white cells, suggesting a role in the stabilization of a repressive chromatin state. Deletion of YNG2, a subunit of the NuA4 H4 histone acetyltransferase (HAT) that targets SWR1 activity through histone acetylation, produces a switching phenotype similar to that of swr1, and both may act downstream of the GlcNAc signaling pathway. We further uncovered a genetic interaction between swr1 and elevated H3K56ac with the discovery that the swr1 deletion mutant is highly sensitive to nicotinamide. Our results suggest that the interaction of H2A.Z and H3K56ac regulates epigenetic switching at the nucleosome level, as well as having global effects.
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32
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Gadaleta MC, Iwasaki O, Noguchi C, Noma KI, Noguchi E. Chromatin immunoprecipitation to detect DNA replication and repair factors. Methods Mol Biol 2015; 1300:169-86. [PMID: 25916713 DOI: 10.1007/978-1-4939-2596-4_12] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
DNA replication is tightly coupled with DNA repair processes in order to preserve genomic integrity. During DNA replication, the replication fork encounters a variety of obstacles including DNA damage/adducts, secondary structures, and programmed fork-blocking sites, which are all difficult to replicate. The replication fork also collides with the transcription machinery, which shares the template DNA with the replisome complex. Under these conditions, replication forks stall, causing replication stress and/or fork collapse, ultimately leading to genomic instability. The mechanisms to overcome these replication problems remain elusive. Therefore, it is important to investigate how DNA repair and replication factors are recruited and coordinated at chromosomal regions that are difficult to replicate. In this chapter, we describe a chromatin immunoprecipitation method to locate proteins required for DNA repair during DNA replication in the fission yeast Schizosaccharomyces pombe. This method can also easily be adapted to study replisome components or chromatin-associated factors.
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Affiliation(s)
- Mariana C Gadaleta
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, 245 N 15th Street, Philadelphia, PA, 19102, USA
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Clément-Ziza M, Marsellach FX, Codlin S, Papadakis MA, Reinhardt S, Rodríguez-López M, Martin S, Marguerat S, Schmidt A, Lee E, Workman CT, Bähler J, Beyer A. Natural genetic variation impacts expression levels of coding, non-coding, and antisense transcripts in fission yeast. Mol Syst Biol 2014; 10:764. [PMID: 25432776 PMCID: PMC4299605 DOI: 10.15252/msb.20145123] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Our current understanding of how natural genetic variation affects gene expression beyond
well-annotated coding genes is still limited. The use of deep sequencing technologies for the study
of expression quantitative trait loci (eQTLs) has the potential to close this gap. Here, we
generated the first recombinant strain library for fission yeast and conducted an RNA-seq-based QTL
study of the coding, non-coding, and antisense transcriptomes. We show that the frequency of distal
effects (trans-eQTLs) greatly exceeds the number of local effects
(cis-eQTLs) and that non-coding RNAs are as likely to be affected by eQTLs as
protein-coding RNAs. We identified a genetic variation of swc5 that modifies the
levels of 871 RNAs, with effects on both sense and antisense transcription, and show that this
effect most likely goes through a compromised deposition of the histone variant H2A.Z. The strains,
methods, and datasets generated here provide a rich resource for future studies.
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Affiliation(s)
- Mathieu Clément-Ziza
- Biotechnology Centre, Technische Universität Dresden, Dresden, Germany Cologne Cluster of Excellence in Cellular Stress Responses in Aging-associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - Francesc X Marsellach
- Department of Genetics, Evolution & Environment and UCL Genetics Institute, University College London, London, UK
| | - Sandra Codlin
- Department of Genetics, Evolution & Environment and UCL Genetics Institute, University College London, London, UK
| | - Manos A Papadakis
- Center for Biological Sequence Analysis, Department of Systems Biology, Technical University of Denmark, Lyngby, Denmark
| | - Susanne Reinhardt
- Biotechnology Centre, Technische Universität Dresden, Dresden, Germany
| | - María Rodríguez-López
- Department of Genetics, Evolution & Environment and UCL Genetics Institute, University College London, London, UK
| | - Stuart Martin
- Department of Genetics, Evolution & Environment and UCL Genetics Institute, University College London, London, UK
| | - Samuel Marguerat
- Department of Genetics, Evolution & Environment and UCL Genetics Institute, University College London, London, UK
| | | | - Eunhye Lee
- Department of Genetics, Evolution & Environment and UCL Genetics Institute, University College London, London, UK
| | - Christopher T Workman
- Center for Biological Sequence Analysis, Department of Systems Biology, Technical University of Denmark, Lyngby, Denmark
| | - Jürg Bähler
- Department of Genetics, Evolution & Environment and UCL Genetics Institute, University College London, London, UK
| | - Andreas Beyer
- Biotechnology Centre, Technische Universität Dresden, Dresden, Germany Cologne Cluster of Excellence in Cellular Stress Responses in Aging-associated Diseases (CECAD), University of Cologne, Cologne, Germany
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34
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Tosti E, Katakowski JA, Schaetzlein S, Kim HS, Ryan CJ, Shales M, Roguev A, Krogan NJ, Palliser D, Keogh MC, Edelmann W. Evolutionarily conserved genetic interactions with budding and fission yeast MutS identify orthologous relationships in mismatch repair-deficient cancer cells. Genome Med 2014; 6:68. [PMID: 25302077 PMCID: PMC4189729 DOI: 10.1186/s13073-014-0068-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2013] [Accepted: 08/28/2014] [Indexed: 12/13/2022] Open
Abstract
Background The evolutionarily conserved DNA mismatch repair (MMR) system corrects base-substitution and insertion-deletion mutations generated during erroneous replication. The mutation or inactivation of many MMR factors strongly predisposes to cancer, where the resulting tumors often display resistance to standard chemotherapeutics. A new direction to develop targeted therapies is the harnessing of synthetic genetic interactions, where the simultaneous loss of two otherwise non-essential factors leads to reduced cell fitness or death. High-throughput screening in human cells to directly identify such interactors for disease-relevant genes is now widespread, but often requires extensive case-by-case optimization. Here we asked if conserved genetic interactors (CGIs) with MMR genes from two evolutionary distant yeast species (Saccharomyces cerevisiae and Schizosaccharomyzes pombe) can predict orthologous genetic relationships in higher eukaryotes. Methods High-throughput screening was used to identify genetic interaction profiles for the MutSα and MutSβ heterodimer subunits (msh2Δ, msh3Δ, msh6Δ) of fission yeast. Selected negative interactors with MutSβ (msh2Δ/msh3Δ) were directly analyzed in budding yeast, and the CGI with SUMO-protease Ulp2 further examined after RNA interference/drug treatment in MSH2-deficient and -proficient human cells. Results This study identified distinct genetic profiles for MutSα and MutSβ, and supports a role for the latter in recombinatorial DNA repair. Approximately 28% of orthologous genetic interactions with msh2Δ/msh3Δ are conserved in both yeasts, a degree consistent with global trends across these species. Further, the CGI between budding/fission yeast msh2 and SUMO-protease Ulp2 is maintained in human cells (MSH2/SENP6), and enhanced by Olaparib, a PARP inhibitor that induces the accumulation of single-strand DNA breaks. This identifies SENP6 as a promising new target for the treatment of MMR-deficient cancers. Conclusion Our findings demonstrate the utility of employing evolutionary distance in tractable lower eukaryotes to predict orthologous genetic relationships in higher eukaryotes. Moreover, we provide novel insights into the genome maintenance functions of a critical DNA repair complex and propose a promising targeted treatment for MMR deficient tumors. Electronic supplementary material The online version of this article (doi:10.1186/s13073-014-0068-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Elena Tosti
- Department of Cell Biology, Albert Einstein College of Medicine, New York, USA
| | - Joseph A Katakowski
- Department of Microbiology & Immunology, Albert Einstein College of Medicine, New York, USA
| | - Sonja Schaetzlein
- Department of Cell Biology, Albert Einstein College of Medicine, New York, USA
| | - Hyun-Soo Kim
- Department of Cell Biology, Albert Einstein College of Medicine, New York, USA
| | - Colm J Ryan
- Department of Cellular & Molecular Pharmacology, UCSF, San Francisco, USA ; California Institute for Quantitative Biosciences, San Francisco, USA ; School of Medicine and Medical Science, University College Dublin, Dublin, Ireland
| | - Michael Shales
- Department of Cellular & Molecular Pharmacology, UCSF, San Francisco, USA
| | - Assen Roguev
- Department of Cellular & Molecular Pharmacology, UCSF, San Francisco, USA
| | - Nevan J Krogan
- Department of Cellular & Molecular Pharmacology, UCSF, San Francisco, USA ; California Institute for Quantitative Biosciences, San Francisco, USA ; J. David Gladstone Institutes, San Francisco, USA
| | - Deborah Palliser
- Department of Microbiology & Immunology, Albert Einstein College of Medicine, New York, USA
| | | | - Winfried Edelmann
- Department of Cell Biology, Albert Einstein College of Medicine, New York, USA
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35
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A novel histone deacetylase complex in the control of transcription and genome stability. Mol Cell Biol 2014; 34:3500-14. [PMID: 25002536 DOI: 10.1128/mcb.00519-14] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The acetylation state of histones, controlled by histone acetyltransferases (HATs) and deacetylases (HDACs), profoundly affects DNA transcription and repair by modulating chromatin accessibility to the cellular machinery. The Schizosaccharomyces pombe HDAC Clr6 (human HDAC1) binds to different sets of proteins that define functionally distinct complexes: I, I', and II. Here, we determine the composition, architecture, and functions of a new Clr6 HDAC complex, I'', delineated by the novel proteins Nts1, Mug165, and Png3. Deletion of nts1 causes increased sensitivity to genotoxins and deregulated expression of Tf2 elements, long noncoding RNA, and subtelomeric and stress-related genes. Similar, but more pervasive, phenotypes are observed upon Clr6 inactivation, supporting the designation of complex I'' as a mediator of a key subset of Clr6 functions. We also reveal that with the exception of Tf2 elements, the genome-wide loading sites and loci regulated by Clr6 I″ do not correlate. Instead, Nts1 loads at genes that are expressed in midmeiosis, following oxidative stress, or are periodically expressed. Collective data suggest that Clr6 I'' has (i) indirect effects on gene expression, conceivably by mediating higher-order chromatin organization of subtelomeres and Tf2 elements, and (ii) direct effects on the transcription of specific genes in response to certain cellular or environmental stimuli.
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36
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Anver S, Roguev A, Zofall M, Krogan NJ, Grewal SIS, Harmer SL. Yeast X-chromosome-associated protein 5 (Xap5) functions with H2A.Z to suppress aberrant transcripts. EMBO Rep 2014; 15:894-902. [PMID: 24957674 DOI: 10.15252/embr.201438902] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Chromatin regulatory proteins affect diverse developmental and environmental response pathways via their influence on nuclear processes such as the regulation of gene expression. Through a genome-wide genetic screen, we implicate a novel protein called X-chromosome-associated protein 5 (Xap5) in chromatin regulation. We show that Xap5 is a chromatin-associated protein acting in a similar manner as the histone variant H2A.Z to suppress expression of antisense and repeat element transcripts throughout the fission yeast genome. Xap5 is highly conserved across eukaryotes, and a plant homolog rescues xap5 mutant yeast. We propose that Xap5 likely functions as a chromatin regulator in diverse organisms.
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Affiliation(s)
- Shajahan Anver
- Department of Plant Biology, College of Biological Sciences University of California, Davis, CA, USA
| | - Assen Roguev
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA, USA
| | - Martin Zofall
- Laboratory of Biochemistry and Molecular Biology, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
| | - Nevan J Krogan
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA, USA
| | - Shiv I S Grewal
- Laboratory of Biochemistry and Molecular Biology, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
| | - Stacey L Harmer
- Department of Plant Biology, College of Biological Sciences University of California, Davis, CA, USA
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37
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Vanoosthuyse V, Legros P, van der Sar SJA, Yvert G, Toda K, Le Bihan T, Watanabe Y, Hardwick K, Bernard P. CPF-associated phosphatase activity opposes condensin-mediated chromosome condensation. PLoS Genet 2014; 10:e1004415. [PMID: 24945319 PMCID: PMC4063703 DOI: 10.1371/journal.pgen.1004415] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Accepted: 04/16/2014] [Indexed: 12/03/2022] Open
Abstract
Functional links connecting gene transcription and condensin-mediated chromosome condensation have been established in species ranging from prokaryotes to vertebrates. However, the exact nature of these links remains misunderstood. Here we show in fission yeast that the 3′ end RNA processing factor Swd2.2, a component of the Cleavage and Polyadenylation Factor (CPF), is a negative regulator of condensin-mediated chromosome condensation. Lack of Swd2.2 does not affect the assembly of the CPF but reduces its association with chromatin. This causes only limited, context-dependent effects on gene expression and transcription termination. However, CPF-associated Swd2.2 is required for the association of Protein Phosphatase 1 PP1Dis2 with chromatin, through an interaction with Ppn1, a protein that we identify as the fission yeast homologue of vertebrate PNUTS. We demonstrate that Swd2.2, Ppn1 and PP1Dis2 form an independent module within the CPF, which provides an essential function in the absence of the CPF-associated Ssu72 phosphatase. We show that Ppn1 and Ssu72, like Swd2.2, are also negative regulators of condensin-mediated chromosome condensation. We conclude that Swd2.2 opposes condensin-mediated chromosome condensation by facilitating the function of the two CPF-associated phosphatases PP1 and Ssu72. Failure to properly condense chromosomes prior to their segregation in mitosis can lead to genome instability. The evolutionary-conserved condensin complex is key to the condensation process but the molecular mechanisms underlying its localization pattern on chromosomes remain unclear. Previous observations showed that the localization of condensin is intimately linked to regions of high transcription, although, somewhat paradoxically, its association with chromatin is disrupted by a processive polymerase activity. Here we identify several RNA processing factors as negative regulators of condensin in fission yeast. Two of these factors associate with PP1 phosphatase as an independent entity within the Cleavage and Polyadenylation Factor (CPF), a complex key for 3′ end RNA processing. Lack of this module induces only minor and context-dependent effects on gene expression. Our data suggest that this module helps maintaining the proper level of phosphatase activity within the CPF and thereby opposes the function of condensin in mitotic chromosome condensation.
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Affiliation(s)
- Vincent Vanoosthuyse
- CNRS, UMR5239, LBMC; Ecole Normale Supérieure de Lyon; Université Lyon 01, Lyon, France
- Wellcome Trust Centre for Cell Biology, University of Edinburgh, Edinburgh, United Kingdom
- * E-mail:
| | - Pénélope Legros
- CNRS, UMR5239, LBMC; Ecole Normale Supérieure de Lyon; Université Lyon 01, Lyon, France
| | | | - Gaël Yvert
- CNRS, UMR5239, LBMC; Ecole Normale Supérieure de Lyon; Université Lyon 01, Lyon, France
| | - Kenji Toda
- Chromosome Dynamics, Institute of Molecular and Cellular Biosciences, The University of Tokyo, Yayoi, Bunkyo-ku, Tokyo, Japan
| | - Thierry Le Bihan
- SynthSys Edinburgh, The University of Edinburgh, Edinburgh, United Kingdom
| | - Yoshinori Watanabe
- Chromosome Dynamics, Institute of Molecular and Cellular Biosciences, The University of Tokyo, Yayoi, Bunkyo-ku, Tokyo, Japan
| | - Kevin Hardwick
- Wellcome Trust Centre for Cell Biology, University of Edinburgh, Edinburgh, United Kingdom
| | - Pascal Bernard
- CNRS, UMR5239, LBMC; Ecole Normale Supérieure de Lyon; Université Lyon 01, Lyon, France
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38
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Tapia-Alveal C, Lin SJ, Yeoh A, Jabado OJ, O'Connell MJ. H2A.Z-dependent regulation of cohesin dynamics on chromosome arms. Mol Cell Biol 2014; 34:2092-104. [PMID: 24687850 PMCID: PMC4019066 DOI: 10.1128/mcb.00193-14] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Revised: 02/25/2014] [Accepted: 03/21/2014] [Indexed: 11/20/2022] Open
Abstract
Structural maintenance of chromosomes (SMC) complexes and DNA topoisomerases are major determinants of chromosome structure and dynamics. The cohesin complex embraces sister chromatids throughout interphase, but during mitosis most cohesin is stripped from chromosome arms by early prophase, while the remaining cohesin at kinetochores is cleaved at anaphase. This two-step removal of cohesin is required for sister chromatids to separate. The cohesin-related Smc5/6 complex has been studied mostly as a determinant of DNA repair via homologous recombination. However, chromosome segregation fails in Smc5/6 null mutants or cells treated with small interfering RNAs. This also occurs in Smc5/6 hypomorphs in the fission yeast Schizosaccharomyces pombe following genotoxic and replication stress, or topoisomerase II dysfunction, and these mitotic defects are due to the postanaphase retention of cohesin on chromosome arms. Here we show that mitotic and repair roles for Smc5/6 are genetically separable in S. pombe. Further, we identified the histone variant H2A.Z as a critical factor to modulate cohesin dynamics, and cells lacking H2A.Z suppress the mitotic defects conferred by Smc5/6 dysfunction. Together, H2A.Z and the SMC complexes ensure genome integrity through accurate chromosome segregation.
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Affiliation(s)
- Claudia Tapia-Alveal
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Su-Jiun Lin
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Aaron Yeoh
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Omar J. Jabado
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Matthew J. O'Connell
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
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Rossetto D, Cramet M, Wang AY, Steunou AL, Lacoste N, Schulze JM, Côté V, Monnet-Saksouk J, Piquet S, Nourani A, Kobor MS, Côté J. Eaf5/7/3 form a functionally independent NuA4 submodule linked to RNA polymerase II-coupled nucleosome recycling. EMBO J 2014; 33:1397-415. [PMID: 24843044 DOI: 10.15252/embj.201386433] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The NuA4 histone acetyltransferase complex is required for gene regulation, cell cycle progression, and DNA repair. Dissection of the 13-subunit complex reveals that the Eaf7 subunit bridges Eaf5 with Eaf3, a H3K36me3-binding chromodomain protein, and this Eaf5/7/3 trimer is anchored to NuA4 through Eaf5. This trimeric subcomplex represents a functional module, and a large portion exists in a native form outside the NuA4 complex. Gene-specific and genome-wide location analyses indicate that Eaf5/7/3 correlates with transcription activity and is enriched over the coding region. In agreement with a role in transcription elongation, the Eaf5/7/3 trimer interacts with phosphorylated RNA polymerase II and helps its progression. Loss of Eaf5/7/3 partially suppresses intragenic cryptic transcription arising in set2 mutants, supporting a role in nucleosome destabilization. On the other hand, loss of the trimer leads to an increase of replication-independent histone exchange over the coding region of transcribed genes. Taken together, these results lead to a model where Eaf5/7/3 associates with elongating polymerase to promote the disruption of nucleosomes in its path, but also their refolding in its wake.
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Affiliation(s)
- Dorine Rossetto
- St-Patrick Research Group in Basic Oncology, Laval University Cancer Research Center Centre de Recherche du CHU de Québec-Axe Oncologie Hôtel-Dieu de Québec, Quebec City, QC, Canada
| | - Myriam Cramet
- St-Patrick Research Group in Basic Oncology, Laval University Cancer Research Center Centre de Recherche du CHU de Québec-Axe Oncologie Hôtel-Dieu de Québec, Quebec City, QC, Canada
| | - Alice Y Wang
- Center for Molecular Medicine and Therapeutics, Child and Family Research Institute, Vancouver, BC, Canada
| | - Anne-Lise Steunou
- St-Patrick Research Group in Basic Oncology, Laval University Cancer Research Center Centre de Recherche du CHU de Québec-Axe Oncologie Hôtel-Dieu de Québec, Quebec City, QC, Canada
| | - Nicolas Lacoste
- St-Patrick Research Group in Basic Oncology, Laval University Cancer Research Center Centre de Recherche du CHU de Québec-Axe Oncologie Hôtel-Dieu de Québec, Quebec City, QC, Canada
| | - Julia M Schulze
- Center for Molecular Medicine and Therapeutics, Child and Family Research Institute, Vancouver, BC, Canada
| | - Valérie Côté
- St-Patrick Research Group in Basic Oncology, Laval University Cancer Research Center Centre de Recherche du CHU de Québec-Axe Oncologie Hôtel-Dieu de Québec, Quebec City, QC, Canada
| | - Julie Monnet-Saksouk
- St-Patrick Research Group in Basic Oncology, Laval University Cancer Research Center Centre de Recherche du CHU de Québec-Axe Oncologie Hôtel-Dieu de Québec, Quebec City, QC, Canada
| | - Sandra Piquet
- St-Patrick Research Group in Basic Oncology, Laval University Cancer Research Center Centre de Recherche du CHU de Québec-Axe Oncologie Hôtel-Dieu de Québec, Quebec City, QC, Canada
| | - Amine Nourani
- St-Patrick Research Group in Basic Oncology, Laval University Cancer Research Center Centre de Recherche du CHU de Québec-Axe Oncologie Hôtel-Dieu de Québec, Quebec City, QC, Canada
| | - Michael S Kobor
- Center for Molecular Medicine and Therapeutics, Child and Family Research Institute, Vancouver, BC, Canada
| | - Jacques Côté
- St-Patrick Research Group in Basic Oncology, Laval University Cancer Research Center Centre de Recherche du CHU de Québec-Axe Oncologie Hôtel-Dieu de Québec, Quebec City, QC, Canada
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Billon P, Côté J. Precise deposition of histone H2A.Z in chromatin for genome expression and maintenance. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2014; 1819:290-302. [PMID: 24459731 DOI: 10.1016/j.bbagrm.2011.10.004] [Citation(s) in RCA: 81] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Histone variant H2A.Z is essential in higher eukaryotes and has different functions in the cell. Several studies indicate that H2A.Z is found at specific loci in the genome such as regulatory-gene regions, where it poises genes for transcription. Itsdeposition creates chromatin regions with particular structural characteristics which could favor rapid transcription activation. This review focuses on the highly regulated mechanism of H2A.Z deposition in chromatin which is essential for genome integrity. Chaperones escort H2A.Z to large ATP-dependent chromatin remodeling enzymes which are responsible for its deposition/eviction. Over the last ten years, biochemical, genetic and genomic studies helped us understand the precise role of these complexes in this process. It hasbeen suggested that a cooperation occurs between histone acetyltransferase and chromatin remodeling activities to incorporate H2A.Z in chromatin. Its regulated deposition near centromeres and telomeres also shows its implication in chromosomal structure integrity and parallels a role in DNA damage response. Thedynamics of H2A.Z deposition/eviction at specific loci was shown to be critical for genome expression andmaintenance, thus cell fate. Altogether, recent findings reassert the importance of the regulated depositionof this histone variant. This article is part of a Special Issue entitled: Histone chaperones and Chromatin assembly.
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41
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Kim HS, Mukhopadhyay R, Rothbart SB, Silva AC, Vanoosthuyse V, Radovani E, Kislinger T, Roguev A, Ryan CJ, Xu J, Jahari H, Hardwick KG, Greenblatt JF, Krogan NJ, Fillingham JS, Strahl BD, Bouhassira EE, Edelmann W, Keogh MC. Identification of a BET family bromodomain/casein kinase II/TAF-containing complex as a regulator of mitotic condensin function. Cell Rep 2014; 6:892-905. [PMID: 24565511 DOI: 10.1016/j.celrep.2014.01.029] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Revised: 10/20/2013] [Accepted: 01/23/2014] [Indexed: 11/26/2022] Open
Abstract
Condensin is a central regulator of mitotic genome structure with mutants showing poorly condensed chromosomes and profound segregation defects. Here, we identify NCT, a complex comprising the Nrc1 BET-family tandem bromodomain protein (SPAC631.02), casein kinase II (CKII), and several TAFs, as a regulator of condensin function. We show that NCT and condensin bind similar genomic regions but only briefly colocalize during the periods of chromosome condensation and decondensation. This pattern of NCT binding at the core centromere, the region of maximal condensin enrichment, tracks the abundance of acetylated histone H4, as regulated by the Hat1-Mis16 acetyltransferase complex and recognized by the first Nrc1 bromodomain. Strikingly, mutants in NCT or Hat1-Mis16 restore the formation of segregation-competent chromosomes in cells containing defective condensin. These results are consistent with a model where NCT targets CKII to chromatin in a cell-cycle-directed manner in order to modulate the activity of condensin during chromosome condensation and decondensation.
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Affiliation(s)
- Hyun-Soo Kim
- Department of Cell Biology, Albert Einstein College of Medicine, New York, NY 10454, USA
| | - Rituparna Mukhopadhyay
- Department of Cell Biology, Albert Einstein College of Medicine, New York, NY 10454, USA
| | - Scott B Rothbart
- Department of Biochemistry and Biophysics, UNC School of Medicine, Chapel Hill, NC 27599, USA
| | - Andrea C Silva
- Department of Cell Biology, Albert Einstein College of Medicine, New York, NY 10454, USA
| | - Vincent Vanoosthuyse
- Wellcome Trust Centre for Cell Biology, University of Edinburgh, Edinburgh EH9 3QR, Scotland
| | - Ernest Radovani
- Department of Chemistry and Biology, Ryerson University, Toronto, ON M5B 2K3, Canada
| | | | - Assen Roguev
- Department of Cellular and Molecular Pharmacology, UCSF, San Francisco, CA 94158, USA; California Institute for Quantitative Biosciences, San Francisco, CA 94158, USA
| | - Colm J Ryan
- Department of Cellular and Molecular Pharmacology, UCSF, San Francisco, CA 94158, USA; California Institute for Quantitative Biosciences, San Francisco, CA 94158, USA; School of Medicine & Medical Science, University College, Dublin 4, Ireland
| | - Jiewei Xu
- Department of Cellular and Molecular Pharmacology, UCSF, San Francisco, CA 94158, USA; California Institute for Quantitative Biosciences, San Francisco, CA 94158, USA
| | - Harlizawati Jahari
- Department of Cellular and Molecular Pharmacology, UCSF, San Francisco, CA 94158, USA; California Institute for Quantitative Biosciences, San Francisco, CA 94158, USA; Malaysian Institute of Pharmaceuticals and Nutraceuticals, 11800 USM Penang, Malaysia
| | - Kevin G Hardwick
- Wellcome Trust Centre for Cell Biology, University of Edinburgh, Edinburgh EH9 3QR, Scotland
| | - Jack F Greenblatt
- Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, ON M5S 3E1, Canada
| | - Nevan J Krogan
- Department of Cellular and Molecular Pharmacology, UCSF, San Francisco, CA 94158, USA; California Institute for Quantitative Biosciences, San Francisco, CA 94158, USA; J. David Gladstone Institutes, San Francisco, CA 94158, USA
| | - Jeffrey S Fillingham
- Department of Chemistry and Biology, Ryerson University, Toronto, ON M5B 2K3, Canada
| | - Brian D Strahl
- Department of Biochemistry and Biophysics, UNC School of Medicine, Chapel Hill, NC 27599, USA
| | - Eric E Bouhassira
- Department of Cell Biology, Albert Einstein College of Medicine, New York, NY 10454, USA
| | - Winfried Edelmann
- Department of Cell Biology, Albert Einstein College of Medicine, New York, NY 10454, USA
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Abstract
Proteins are not monolithic entities; rather, they can contain multiple domains that mediate distinct interactions, and their functionality can be regulated through post-translational modifications at multiple distinct sites. Traditionally, network biology has ignored such properties of proteins and has instead examined either the physical interactions of whole proteins or the consequences of removing entire genes. In this Review, we discuss experimental and computational methods to increase the resolution of protein-protein, genetic and drug-gene interaction studies to the domain and residue levels. Such work will be crucial for using interaction networks to connect sequence and structural information, and to understand the biological consequences of disease-associated mutations, which will hopefully lead to more effective therapeutic strategies.
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43
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Epigenetically induced paucity of histone H2A.Z stabilizes fission-yeast ectopic centromeres. Nat Struct Mol Biol 2013; 20:1397-406. [PMID: 24186062 DOI: 10.1038/nsmb.2697] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2013] [Accepted: 09/16/2013] [Indexed: 11/08/2022]
Abstract
In most eukaryotes, centromeres are epigenetically defined by nucleosomes that contain the histone H3 variant centromere protein A (CENP-A). Specific targeting of the CENP-A-loading chaperone to the centromere is vital for stable centromere propagation; however, the existence of ectopic centromeres (neocentromeres) indicates that this chaperone can function in different chromatin environments. The mechanism responsible for accommodating the CENP-A chaperone at noncentromeric regions is poorly understood. Here, we report the identification of transient, immature neocentromeres in Schizosaccharomyces pombe that show reduced association with the CENP-A chaperone Scm3, owing to persistence of the histone H2A variant H2A.Z. After the acquisition of adjacent heterochromatin or relocation of the immature neocentromeres to subtelomeric regions, H2A.Z was depleted and Scm3 was replenished, thus leading to subsequent stabilization of the neocentromeres. These findings provide new insights into histone variant-mediated epigenetic control of neocentromere establishment.
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44
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Subramanian V, Mazumder A, Surface LE, Butty VL, Fields PA, Alwan A, Torrey L, Thai KK, Levine SS, Bathe M, Boyer LA. H2A.Z acidic patch couples chromatin dynamics to regulation of gene expression programs during ESC differentiation. PLoS Genet 2013; 9:e1003725. [PMID: 23990805 PMCID: PMC3749939 DOI: 10.1371/journal.pgen.1003725] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2013] [Accepted: 07/01/2013] [Indexed: 12/20/2022] Open
Abstract
The histone H2A variant H2A.Z is essential for embryonic development and for proper control of developmental gene expression programs in embryonic stem cells (ESCs). Divergent regions of amino acid sequence of H2A.Z likely determine its functional specialization compared to core histone H2A. For example, H2A.Z contains three divergent residues in the essential C-terminal acidic patch that reside on the surface of the histone octamer as an uninterrupted acidic patch domain; however, we know little about how these residues contribute to chromatin structure and function. Here, we show that the divergent amino acids Gly92, Asp97, and Ser98 in the H2A.Z C-terminal acidic patch (H2A.Z(AP3)) are critical for lineage commitment during ESC differentiation. H2A.Z is enriched at most H3K4me3 promoters in ESCs including poised, bivalent promoters that harbor both activating and repressive marks, H3K4me3 and H3K27me3 respectively. We found that while H2A.Z(AP3) interacted with its deposition complex and displayed a highly similar distribution pattern compared to wild-type H2A.Z, its enrichment levels were reduced at target promoters. Further analysis revealed that H2A.Z(AP3) was less tightly associated with chromatin, suggesting that the mutant is more dynamic. Notably, bivalent genes in H2A.Z(AP3) ESCs displayed significant changes in expression compared to active genes. Moreover, bivalent genes in H2A.Z(AP3) ESCs gained H3.3, a variant associated with higher nucleosome turnover, compared to wild-type H2A.Z. We next performed single cell imaging to measure H2A.Z dynamics. We found that H2A.Z(AP3) displayed higher mobility in chromatin compared to wild-type H2A.Z by fluorescent recovery after photobleaching (FRAP). Moreover, ESCs treated with the transcriptional inhibitor flavopiridol resulted in a decrease in the H2A.Z(AP3) mobile fraction and an increase in its occupancy at target genes indicating that the mutant can be properly incorporated into chromatin. Collectively, our work suggests that the divergent residues in the H2A.Z acidic patch comprise a unique domain that couples control of chromatin dynamics to the regulation of developmental gene expression patterns during lineage commitment.
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Affiliation(s)
- Vidya Subramanian
- Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - Aprotim Mazumder
- Laboratory for Computational Biology and Biophysics, and Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - Lauren E. Surface
- Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - Vincent L. Butty
- BioMicro Center, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - Paul A. Fields
- Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - Allison Alwan
- Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - Lillian Torrey
- Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - Kevin K. Thai
- Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - Stuart S. Levine
- BioMicro Center, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - Mark Bathe
- Laboratory for Computational Biology and Biophysics, and Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - Laurie A. Boyer
- Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
- * E-mail:
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45
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Histone variant H2A.Z functions in sister chromatid cohesion in Saccharomyces cerevisiae. Mol Cell Biol 2013; 33:3473-81. [PMID: 23816883 DOI: 10.1128/mcb.00162-12] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
H2A.Z is a highly conserved variant of histone H2A with well-characterized roles in transcriptional regulation. We previously reported that H2A.Z and Mcd1, a subunit of the cohesin complex, regulate the establishment of transcriptional silencing at telomeres in Saccharomyces cerevisiae and that H2A.Z broadly dissociated from chromatin during the anaphase-to-telophase transition, coincident with the dissociation of Mcd1 from chromosomes and dissolution of cohesion. In this study, we show that depletion of H2A.Z causes precocious loss of sister chromatid cohesion in yeast without loss of Mcd1 from chromosomes. H2A.Z is deposited into chromatin by the SWR1 complex and is subject to acetylation of its four N-terminal tail lysine residues by the NuA4 and SAGA histone acetyltransferase complexes. We found that cells compromised for function of the SWR1 complex were defective in cohesion, as were cells expressing a form of H2A.Z not subject to acetylation. Finally, inactivation of H2A.Z in metaphase-blocked cells led immediately to cohesion defects, suggesting a direct role for H2A.Z in the maintenance of sister chromatid cohesion.
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Coy S, Volanakis A, Shah S, Vasiljeva L. The Sm complex is required for the processing of non-coding RNAs by the exosome. PLoS One 2013; 8:e65606. [PMID: 23755256 PMCID: PMC3675052 DOI: 10.1371/journal.pone.0065606] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Accepted: 04/27/2013] [Indexed: 12/25/2022] Open
Abstract
A key question in the field of RNA regulation is how some exosome substrates, such as spliceosomal snRNAs and telomerase RNA, evade degradation and are processed into stable, functional RNA molecules. Typical feature of these non-coding RNAs is presence of the Sm complex at the 3′end of the mature RNA molecule. Here, we report that in Saccharomyces cerevisiae presence of intact Sm binding site is required for the exosome-mediated processing of telomerase RNA from a polyadenylated precursor into its mature form and is essential for its function in elongating telomeres. Additionally, we demonstrate that the same pathway is involved in the maturation of snRNAs. Furthermore, the insertion of an Sm binding site into an unstable RNA that is normally completely destroyed by the exosome, leads to its partial stabilization. We also show that telomerase RNA accumulates in Schizosaccharomyces pombe exosome mutants, suggesting a conserved role for the exosome in processing and degradation of telomerase RNA. In summary, our data provide important mechanistic insight into the regulation of exosome dependent RNA processing as well as telomerase RNA biogenesis.
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Affiliation(s)
- Sarah Coy
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Adam Volanakis
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Sneha Shah
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Lidia Vasiljeva
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
- * E-mail:
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47
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Liu B, Yip RK, Zhou Z. Chromatin remodeling, DNA damage repair and aging. Curr Genomics 2013; 13:533-47. [PMID: 23633913 PMCID: PMC3468886 DOI: 10.2174/138920212803251373] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2012] [Revised: 06/19/2012] [Accepted: 07/25/2012] [Indexed: 01/26/2023] Open
Abstract
Cells are constantly exposed to a variety of environmental and endogenous conditions causing DNA damage, which is detected and repaired by conserved DNA repair pathways to maintain genomic integrity. Chromatin remodeling is critical in this process, as the organization of eukaryotic DNA into compact chromatin presents a natural barrier to all DNA-related events. Studies on human premature aging syndromes together with normal aging have suggested that accumulated damages might lead to exhaustion of resources that are required for physiological functions and thus accelerate aging. In this manuscript, combining the present understandings and latest findings, we focus mainly on discussing the role of chromatin remodeling in the repair of DNA double-strand breaks (DSBs) and regulation of aging.
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Affiliation(s)
- Baohua Liu
- Shenzhen Institute of Research and Innovation, The University of Hong Kong, Shenzhen, China ; Department of Biochemistry, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong
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48
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Piazza I, Haering CH, Rutkowska A. Condensin: crafting the chromosome landscape. Chromosoma 2013; 122:175-90. [DOI: 10.1007/s00412-013-0405-1] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2013] [Revised: 03/03/2013] [Accepted: 03/04/2013] [Indexed: 02/06/2023]
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49
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Abstract
Chromatin acts as an organizer and indexer of genomic DNA and is a highly dynamic and regulated structure with properties directly related to its constituent parts. Histone variants are abundant components of chromatin that replace canonical histones in a subset of nucleosomes, thereby altering nucleosomal characteristics. The present review focuses on the H2A variant histones, summarizing current knowledge of how H2A variants can introduce chemical and functional heterogeneity into chromatin, the positions that nucleosomes containing H2A variants occupy in eukaryotic genomes, and the regulation of these localization patterns.
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50
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Hu G, Cui K, Northrup D, Liu C, Wang C, Tang Q, Ge K, Levens D, Crane-Robinson C, Zhao K. H2A.Z facilitates access of active and repressive complexes to chromatin in embryonic stem cell self-renewal and differentiation. Cell Stem Cell 2013; 12:180-92. [PMID: 23260488 PMCID: PMC3570599 DOI: 10.1016/j.stem.2012.11.003] [Citation(s) in RCA: 236] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2012] [Revised: 09/29/2012] [Accepted: 11/08/2012] [Indexed: 10/27/2022]
Abstract
Chromatin modifications have been implicated in the self-renewal and differentiation of embryonic stem cells (ESCs). However, the function of histone variant H2A.Z in ESCs remains unclear. We show that H2A.Z is highly enriched at promoters and enhancers and is required for both efficient self-renewal and differentiation of murine ESCs. H2A.Z deposition leads to an abnormal nucleosome structure, decreased nucleosome occupancy, and increased chromatin accessibility. In self-renewing ESCs, knockdown of H2A.Z compromises OCT4 binding to its target genes and leads to decreased binding of MLL complexes to active genes and of PRC2 complex to repressed genes. During differentiation of ESCs, inhibition of H2A.Z also compromises RA-induced RARα binding, activation of differentiation markers, and the repression of pluripotency genes. We propose that H2A.Z mediates such contrasting activities by acting as a general facilitator that generates access for a variety of complexes, both activating and repressive.
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Affiliation(s)
- Gangqing Hu
- Systems Biology Center, National Heart, Lung and Blood Institute, NIH, Bethesda, MD 20892, USA
| | - Kairong Cui
- Systems Biology Center, National Heart, Lung and Blood Institute, NIH, Bethesda, MD 20892, USA
| | - Daniel Northrup
- Systems Biology Center, National Heart, Lung and Blood Institute, NIH, Bethesda, MD 20892, USA
| | - Chengyu Liu
- Transgenic Mouse Facility, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Chaochen Wang
- Laboratory of Endocrinology and Receptor Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Qingsong Tang
- Systems Biology Center, National Heart, Lung and Blood Institute, NIH, Bethesda, MD 20892, USA
| | - Kai Ge
- Laboratory of Endocrinology and Receptor Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - David Levens
- Laboratory of Pathology, National Cancer Institute, Bethesda, MD 20892, USA
| | - Colyn Crane-Robinson
- Biophysics Laboratories, St. Michael’s Building, University of Portsmouth, Portsmouth, PO1 2DT, UK
| | - Keji Zhao
- Systems Biology Center, National Heart, Lung and Blood Institute, NIH, Bethesda, MD 20892, USA
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