1
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Guérin TM, Barrington C, Pobegalov G, Molodtsov MI, Uhlmann F. An extrinsic motor directs chromatin loop formation by cohesin. EMBO J 2024:10.1038/s44318-024-00202-5. [PMID: 39160275 DOI: 10.1038/s44318-024-00202-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Revised: 07/30/2024] [Accepted: 07/31/2024] [Indexed: 08/21/2024] Open
Abstract
The ring-shaped cohesin complex topologically entraps two DNA molecules to establish sister chromatid cohesion. Cohesin also shapes the interphase chromatin landscape with wide-ranging implications for gene regulation, and cohesin is thought to achieve this by actively extruding DNA loops without topologically entrapping DNA. The 'loop extrusion' hypothesis finds motivation from in vitro observations-whether this process underlies in vivo chromatin loop formation remains untested. Here, using the budding yeast S. cerevisiae, we generate cohesin variants that have lost their ability to extrude DNA loops but retain their ability to topologically entrap DNA. Analysis of these variants suggests that in vivo chromatin loops form independently of loop extrusion. Instead, we find that transcription promotes loop formation, and acts as an extrinsic motor that expands these loops and defines their ultimate positions. Our results necessitate a re-evaluation of the loop extrusion hypothesis. We propose that cohesin, akin to sister chromatid cohesion establishment at replication forks, forms chromatin loops by DNA-DNA capture at places of transcription, thus unifying cohesin's two roles in chromosome segregation and interphase genome organisation.
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Affiliation(s)
- Thomas M Guérin
- Chromosome Segregation Laboratory, The Francis Crick Institute, London, UK
- Université Paris Cité and Université Paris-Saclay, Inserm, CEA, Stabilité Génétique Cellules Souches et Radiations, Fontenay-aux-Roses, France
| | - Christopher Barrington
- Bioinformatics & Biostatistics Science Technology Platform, The Francis Crick Institute, London, UK
| | - Georgii Pobegalov
- Mechanobiology and Biophysics Laboratory, The Francis Crick Institute, London, UK
- Department of Physics and Astronomy, University College London, London, UK
| | - Maxim I Molodtsov
- Mechanobiology and Biophysics Laboratory, The Francis Crick Institute, London, UK
- Department of Physics and Astronomy, University College London, London, UK
| | - Frank Uhlmann
- Chromosome Segregation Laboratory, The Francis Crick Institute, London, UK.
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2
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Jeppsson K, Pradhan B, Sutani T, Sakata T, Umeda Igarashi M, Berta DG, Kanno T, Nakato R, Shirahige K, Kim E, Björkegren C. Loop-extruding Smc5/6 organizes transcription-induced positive DNA supercoils. Mol Cell 2024; 84:867-882.e5. [PMID: 38295804 DOI: 10.1016/j.molcel.2024.01.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Revised: 11/16/2023] [Accepted: 01/08/2024] [Indexed: 03/10/2024]
Abstract
The structural maintenance of chromosomes (SMC) protein complexes-cohesin, condensin, and the Smc5/6 complex (Smc5/6)-are essential for chromosome function. At the molecular level, these complexes fold DNA by loop extrusion. Accordingly, cohesin creates chromosome loops in interphase, and condensin compacts mitotic chromosomes. However, the role of Smc5/6's recently discovered DNA loop extrusion activity is unknown. Here, we uncover that Smc5/6 associates with transcription-induced positively supercoiled DNA at cohesin-dependent loop boundaries on budding yeast (Saccharomyces cerevisiae) chromosomes. Mechanistically, single-molecule imaging reveals that dimers of Smc5/6 specifically recognize the tip of positively supercoiled DNA plectonemes and efficiently initiate loop extrusion to gather the supercoiled DNA into a large plectonemic loop. Finally, Hi-C analysis shows that Smc5/6 links chromosomal regions containing transcription-induced positive supercoiling in cis. Altogether, our findings indicate that Smc5/6 controls the three-dimensional organization of chromosomes by recognizing and initiating loop extrusion on positively supercoiled DNA.
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Affiliation(s)
- Kristian Jeppsson
- Karolinska Institutet, Department of Cell and Molecular Biology, Biomedicum, Tomtebodavägen 16, 171 77 Stockholm, Sweden; Karolinska Institutet, Department of Biosciences and Nutrition, Neo, Hälsovägen 7c, 141 83 Huddinge, Sweden; Institute for Quantitative Biosciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan.
| | - Biswajit Pradhan
- Max Planck Institute of Biophysics, 60438 Frankfurt am Main, Germany
| | - Takashi Sutani
- Institute for Quantitative Biosciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan
| | - Toyonori Sakata
- Karolinska Institutet, Department of Cell and Molecular Biology, Biomedicum, Tomtebodavägen 16, 171 77 Stockholm, Sweden; Karolinska Institutet, Department of Biosciences and Nutrition, Neo, Hälsovägen 7c, 141 83 Huddinge, Sweden; Institute for Quantitative Biosciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan
| | - Miki Umeda Igarashi
- Karolinska Institutet, Department of Cell and Molecular Biology, Biomedicum, Tomtebodavägen 16, 171 77 Stockholm, Sweden; Karolinska Institutet, Department of Biosciences and Nutrition, Neo, Hälsovägen 7c, 141 83 Huddinge, Sweden
| | - Davide Giorgio Berta
- Karolinska Institutet, Department of Cell and Molecular Biology, Biomedicum, Tomtebodavägen 16, 171 77 Stockholm, Sweden
| | - Takaharu Kanno
- Karolinska Institutet, Department of Cell and Molecular Biology, Biomedicum, Tomtebodavägen 16, 171 77 Stockholm, Sweden; Karolinska Institutet, Department of Biosciences and Nutrition, Neo, Hälsovägen 7c, 141 83 Huddinge, Sweden
| | - Ryuichiro Nakato
- Institute for Quantitative Biosciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan
| | - Katsuhiko Shirahige
- Karolinska Institutet, Department of Cell and Molecular Biology, Biomedicum, Tomtebodavägen 16, 171 77 Stockholm, Sweden; Karolinska Institutet, Department of Biosciences and Nutrition, Neo, Hälsovägen 7c, 141 83 Huddinge, Sweden; Institute for Quantitative Biosciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan
| | - Eugene Kim
- Max Planck Institute of Biophysics, 60438 Frankfurt am Main, Germany.
| | - Camilla Björkegren
- Karolinska Institutet, Department of Cell and Molecular Biology, Biomedicum, Tomtebodavägen 16, 171 77 Stockholm, Sweden; Karolinska Institutet, Department of Biosciences and Nutrition, Neo, Hälsovägen 7c, 141 83 Huddinge, Sweden.
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3
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Murayama Y, Endo S, Kurokawa Y, Kurita A, Iwasaki S, Araki H. Coordination of cohesin and DNA replication observed with purified proteins. Nature 2024; 626:653-660. [PMID: 38267580 DOI: 10.1038/s41586-023-07003-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Accepted: 12/19/2023] [Indexed: 01/26/2024]
Abstract
Two newly duplicated copies of genomic DNA are held together by the ring-shaped cohesin complex to ensure faithful inheritance of the genome during cell division1-3. Cohesin mediates sister chromatid cohesion by topologically entrapping two sister DNAs during DNA replication4,5, but how cohesion is established at the replication fork is poorly understood. Here, we studied the interplay between cohesin and replication by reconstituting a functional replisome using purified proteins. Once DNA is encircled before replication, the cohesin ring accommodates replication in its entirety, from initiation to termination, leading to topological capture of newly synthesized DNA. This suggests that topological cohesin loading is a critical molecular prerequisite to cope with replication. Paradoxically, topological loading per se is highly rate limiting and hardly occurs under the replication-competent physiological salt concentration. This inconsistency is resolved by the replisome-associated cohesion establishment factors Chl1 helicase and Ctf4 (refs. 6,7), which promote cohesin loading specifically during continuing replication. Accordingly, we found that bubble DNA, which mimics the state of DNA unwinding, induces topological cohesin loading and this is further promoted by Chl1. Thus, we propose that cohesin converts the initial electrostatic DNA-binding mode to a topological embrace when it encounters unwound DNA structures driven by enzymatic activities including replication. Together, our results show how cohesin initially responds to replication, and provide a molecular model for the establishment of sister chromatid cohesion.
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Affiliation(s)
- Yasuto Murayama
- Department of Chromosome Science, National Institute of Genetics, Mishima, Japan.
- Department of Genetics, Graduate University for Advanced Studies (SOUKENDAI), Mishima, Japan.
- PRESTO, Japan Science and Technology Agency (JST), Kawaguchi, Japan.
| | - Shizuko Endo
- Department of Chromosome Science, National Institute of Genetics, Mishima, Japan
| | - Yumiko Kurokawa
- Department of Chromosome Science, National Institute of Genetics, Mishima, Japan
- Department of Genetics, Graduate University for Advanced Studies (SOUKENDAI), Mishima, Japan
| | - Ayako Kurita
- Department of Chromosome Science, National Institute of Genetics, Mishima, Japan
| | - Sanae Iwasaki
- Department of Chromosome Science, National Institute of Genetics, Mishima, Japan
| | - Hiroyuki Araki
- Department of Chromosome Science, National Institute of Genetics, Mishima, Japan
- Joint Support-Centre for Data Science Research, Research Organisation of Information and Systems, Tachikawa, Japan
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4
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Shrestha S, Minamino M, Chen ZA, Bouchoux C, Rappsilber J, Uhlmann F. Replisome-cohesin interactions provided by the Tof1-Csm3 and Mrc1 cohesion establishment factors. Chromosoma 2023; 132:117-135. [PMID: 37166686 PMCID: PMC10247859 DOI: 10.1007/s00412-023-00797-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 04/25/2023] [Accepted: 04/26/2023] [Indexed: 05/12/2023]
Abstract
The chromosomal cohesin complex establishes sister chromatid cohesion during S phase, which forms the basis for faithful segregation of DNA replication products during cell divisions. Cohesion establishment is defective in the absence of either of three non-essential Saccharomyces cerevisiae replication fork components Tof1-Csm3 and Mrc1. Here, we investigate how these conserved factors contribute to cohesion establishment. Tof1-Csm3 and Mrc1 serve known roles during DNA replication, including replication checkpoint signaling, securing replication fork speed, as well as recruiting topoisomerase I and the histone chaperone FACT. By modulating each of these functions independently, we rule out that one of these known replication roles explains the contribution of Tof1-Csm3 and Mrc1 to cohesion establishment. Instead, using purified components, we reveal direct and multipronged protein interactions of Tof1-Csm3 and Mrc1 with the cohesin complex. Our findings open the possibility that a series of physical interactions between replication fork components and cohesin facilitate successful establishment of sister chromatid cohesion during DNA replication.
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Affiliation(s)
- Sudikchya Shrestha
- Chromosome Segregation Laboratory, The Francis Crick Institute, London, NW1 1AT, UK
| | - Masashi Minamino
- Chromosome Segregation Laboratory, The Francis Crick Institute, London, NW1 1AT, UK
| | - Zhuo A Chen
- Bioanalytics Unit, Institute of Biotechnology, Technische Universität Berlin, 13355, Berlin, Germany
| | - Céline Bouchoux
- Chromosome Segregation Laboratory, The Francis Crick Institute, London, NW1 1AT, UK
| | - Juri Rappsilber
- Bioanalytics Unit, Institute of Biotechnology, Technische Universität Berlin, 13355, Berlin, Germany
- Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, EH9 3BF, UK
| | - Frank Uhlmann
- Chromosome Segregation Laboratory, The Francis Crick Institute, London, NW1 1AT, UK.
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5
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Mfarej MG, Hyland CA, Sanchez AC, Falk MM, Iovine MK, Skibbens RV. Cohesin: an emerging master regulator at the heart of cardiac development. Mol Biol Cell 2023; 34:rs2. [PMID: 36947206 PMCID: PMC10162415 DOI: 10.1091/mbc.e22-12-0557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 03/10/2023] [Accepted: 03/17/2023] [Indexed: 03/23/2023] Open
Abstract
Cohesins are ATPase complexes that play central roles in cellular processes such as chromosome division, DNA repair, and gene expression. Cohesinopathies arise from mutations in cohesin proteins or cohesin complex regulators and encompass a family of related developmental disorders that present with a range of severe birth defects, affect many different physiological systems, and often lead to embryonic fatality. Treatments for cohesinopathies are limited, in large part due to the lack of understanding of cohesin biology. Thus, characterizing the signaling networks that lie upstream and downstream of cohesin-dependent pathways remains clinically relevant. Here, we highlight alterations in cohesins and cohesin regulators that result in cohesinopathies, with a focus on cardiac defects. In addition, we suggest a novel and more unifying view regarding the mechanisms through which cohesinopathy-based heart defects may arise.
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Affiliation(s)
- Michael G. Mfarej
- Department of Biological Sciences, Lehigh University, Bethlehem, PA 18015
| | - Caitlin A. Hyland
- Department of Biological Sciences, Lehigh University, Bethlehem, PA 18015
| | - Annie C. Sanchez
- Department of Biological Sciences, Lehigh University, Bethlehem, PA 18015
| | - Matthias M. Falk
- Department of Biological Sciences, Lehigh University, Bethlehem, PA 18015
| | - M. Kathryn Iovine
- Department of Biological Sciences, Lehigh University, Bethlehem, PA 18015
| | - Robert V. Skibbens
- Department of Biological Sciences, Lehigh University, Bethlehem, PA 18015
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6
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Yu Z, Kim HJ, Dernburg AF. ATM signaling modulates cohesin behavior in meiotic prophase and proliferating cells. Nat Struct Mol Biol 2023; 30:436-450. [PMID: 36879153 PMCID: PMC10113158 DOI: 10.1038/s41594-023-00929-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Accepted: 01/25/2023] [Indexed: 03/08/2023]
Abstract
Cohesins are ancient and ubiquitous regulators of chromosome architecture and function, but their diverse roles and regulation remain poorly understood. During meiosis, chromosomes are reorganized as linear arrays of chromatin loops around a cohesin axis. This unique organization underlies homolog pairing, synapsis, double-stranded break induction, and recombination. We report that axis assembly in Caenorhabditis elegans is promoted by DNA-damage response (DDR) kinases that are activated at meiotic entry, even in the absence of DNA breaks. Downregulation of the cohesin-destabilizing factor WAPL-1 by ATM-1 promotes axis association of cohesins containing the meiotic kleisins COH-3 and COH-4. ECO-1 and PDS-5 also contribute to stabilizing axis-associated meiotic cohesins. Further, our data suggest that cohesin-enriched domains that promote DNA repair in mammalian cells also depend on WAPL inhibition by ATM. Thus, DDR and Wapl seem to play conserved roles in cohesin regulation in meiotic prophase and proliferating cells.
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Affiliation(s)
- Zhouliang Yu
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA, USA.,Howard Hughes Medical Institute, Chevy Chase, MD, USA.,Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.,California Institute for Quantitative Biosciences, Berkeley, CA, USA
| | - Hyung Jun Kim
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA, USA
| | - Abby F Dernburg
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA, USA. .,Howard Hughes Medical Institute, Chevy Chase, MD, USA. .,Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA. .,California Institute for Quantitative Biosciences, Berkeley, CA, USA.
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7
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Minamino M, Bouchoux C, Canal B, Diffley JFX, Uhlmann F. A replication fork determinant for the establishment of sister chromatid cohesion. Cell 2023; 186:837-849.e11. [PMID: 36693376 DOI: 10.1016/j.cell.2022.12.044] [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: 08/14/2022] [Revised: 11/08/2022] [Accepted: 12/22/2022] [Indexed: 01/24/2023]
Abstract
Concomitant with DNA replication, the chromosomal cohesin complex establishes cohesion between newly replicated sister chromatids. Cohesion establishment requires acetylation of conserved cohesin lysine residues by Eco1 acetyltransferase. Here, we explore how cohesin acetylation is linked to DNA replication. Biochemical reconstitution of replication-coupled cohesin acetylation reveals that transient DNA structures, which form during DNA replication, control the acetylation reaction. As polymerases complete lagging strand replication, strand displacement synthesis produces DNA flaps that are trimmed to result in nicked double-stranded DNA. Both flaps and nicks stimulate cohesin acetylation, while subsequent nick ligation to complete Okazaki fragment maturation terminates the acetylation reaction. A flapped or nicked DNA substrate constitutes a transient molecular clue that directs cohesin acetylation to a window behind the replication fork, next to where cohesin likely entraps both sister chromatids. Our results provide an explanation for how DNA replication is linked to sister chromatid cohesion establishment.
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Affiliation(s)
- Masashi Minamino
- Chromosome Segregation Laboratory, The Francis Crick Institute, London NW1 1AT, UK
| | - Céline Bouchoux
- Chromosome Segregation Laboratory, The Francis Crick Institute, London NW1 1AT, UK
| | - Berta Canal
- Chromosome Replication Laboratory, The Francis Crick Institute, London NW1 1AT, UK
| | - John F X Diffley
- Chromosome Replication Laboratory, The Francis Crick Institute, London NW1 1AT, UK
| | - Frank Uhlmann
- Chromosome Segregation Laboratory, The Francis Crick Institute, London NW1 1AT, UK.
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8
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van Schie JJ, de Lint K, Pai GM, Rooimans MA, Wolthuis RM, de Lange J. MMS22L-TONSL functions in sister chromatid cohesion in a pathway parallel to DSCC1-RFC. Life Sci Alliance 2023; 6:e202201596. [PMID: 36622344 PMCID: PMC9733570 DOI: 10.26508/lsa.202201596] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 11/30/2022] [Accepted: 11/30/2022] [Indexed: 12/14/2022] Open
Abstract
The leading strand-oriented alternative PCNA clamp loader DSCC1-RFC functions in DNA replication, repair, and sister chromatid cohesion (SCC), but how it facilitates these processes is incompletely understood. Here, we confirm that loss of human DSCC1 results in reduced fork speed, increased DNA damage, and defective SCC. Genome-wide CRISPR screens in DSCC1-KO cells reveal multiple synthetically lethal interactions, enriched for DNA replication and cell cycle regulation. We show that DSCC1-KO cells require POLE3 for survival. Co-depletion of DSCC1 and POLE3, which both interact with the catalytic polymerase ε subunit, additively impair DNA replication, suggesting that these factors contribute to leading-strand DNA replication in parallel ways. An additional hit is MMS22L, which in humans forms a heterodimer with TONSL. Synthetic lethality of DSCC1 and MMS22L-TONSL likely results from detrimental SCC loss. We show that MMS22L-TONSL, like DDX11, functions in a SCC establishment pathway parallel to DSCC1-RFC. Because both DSCC1-RFC and MMS22L facilitate ESCO2 recruitment to replication forks, we suggest that distinct ESCO2 recruitment pathways promote SCC establishment following either cohesin conversion or de novo cohesin loading.
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Affiliation(s)
- Janne Jm van Schie
- Department of Human Genetics, Section Oncogenetics, Amsterdam UMC Location Vrije Universiteit Amsterdam, Amsterdam, Netherlands
- Cancer Center Amsterdam, Cancer Biology and Immunology, Amsterdam, Netherlands
| | - Klaas de Lint
- Department of Human Genetics, Section Oncogenetics, Amsterdam UMC Location Vrije Universiteit Amsterdam, Amsterdam, Netherlands
- Cancer Center Amsterdam, Cancer Biology and Immunology, Amsterdam, Netherlands
| | - Govind M Pai
- Department of Human Genetics, Section Oncogenetics, Amsterdam UMC Location Vrije Universiteit Amsterdam, Amsterdam, Netherlands
- Cancer Center Amsterdam, Cancer Biology and Immunology, Amsterdam, Netherlands
| | - Martin A Rooimans
- Department of Human Genetics, Section Oncogenetics, Amsterdam UMC Location Vrije Universiteit Amsterdam, Amsterdam, Netherlands
- Cancer Center Amsterdam, Cancer Biology and Immunology, Amsterdam, Netherlands
| | - Rob Mf Wolthuis
- Department of Human Genetics, Section Oncogenetics, Amsterdam UMC Location Vrije Universiteit Amsterdam, Amsterdam, Netherlands
- Cancer Center Amsterdam, Cancer Biology and Immunology, Amsterdam, Netherlands
| | - Job de Lange
- Department of Human Genetics, Section Oncogenetics, Amsterdam UMC Location Vrije Universiteit Amsterdam, Amsterdam, Netherlands
- Cancer Center Amsterdam, Cancer Biology and Immunology, Amsterdam, Netherlands
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9
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Buskirk S, Skibbens RV. G1-Cyclin2 (Cln2) promotes chromosome hypercondensation in eco1/ctf7 rad61 null cells during hyperthermic stress in Saccharomyces cerevisiae. G3 (BETHESDA, MD.) 2022; 12:6613937. [PMID: 35736360 PMCID: PMC9339302 DOI: 10.1093/g3journal/jkac157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Accepted: 06/13/2022] [Indexed: 11/16/2022]
Abstract
Eco1/Ctf7 is a highly conserved acetyltransferase that activates cohesin complexes and is critical for sister chromatid cohesion, chromosome condensation, DNA damage repair, nucleolar integrity, and gene transcription. Mutations in the human homolog of ECO1 (ESCO2/EFO2), or in genes that encode cohesin subunits, result in severe developmental abnormalities and intellectual disabilities referred to as Roberts syndrome and Cornelia de Lange syndrome, respectively. In yeast, deletion of ECO1 results in cell inviability. Codeletion of RAD61 (WAPL in humans), however, produces viable yeast cells. These eco1 rad61 double mutants, however, exhibit a severe temperature-sensitive growth defect, suggesting that Eco1 or cohesins respond to hyperthermic stress through a mechanism that occurs independent of Rad61. Here, we report that deletion of the G1 cyclin CLN2 rescues the temperature-sensitive lethality otherwise exhibited by eco1 rad61 mutant cells, such that the triple mutant cells exhibit robust growth over a broad range of temperatures. While Cln1, Cln2, and Cln3 are functionally redundant G1 cyclins, neither CLN1 nor CLN3 deletions rescue the temperature-sensitive growth defects otherwise exhibited by eco1 rad61 double mutants. We further provide evidence that CLN2 deletion rescues hyperthermic growth defects independent of START and impacts the state of chromosome condensation. These findings reveal novel roles for Cln2 that are unique among the G1 cyclin family and appear critical for cohesin regulation during hyperthermic stress.
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Affiliation(s)
- Sean Buskirk
- Department of Biology, West Chester University, West Chester, PA 19383, USA
| | - Robert V Skibbens
- Department of Biological Sciences, Lehigh University, Bethlehem, PA 18015, USA
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10
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Jeppsson K, Sakata T, Nakato R, Milanova S, Shirahige K, Björkegren C. Cohesin-dependent chromosome loop extrusion is limited by transcription and stalled replication forks. SCIENCE ADVANCES 2022; 8:eabn7063. [PMID: 35687682 PMCID: PMC9187231 DOI: 10.1126/sciadv.abn7063] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 12/15/2021] [Accepted: 04/27/2022] [Indexed: 05/31/2023]
Abstract
Genome function depends on regulated chromosome folding, and loop extrusion by the protein complex cohesin is essential for this multilayered organization. The chromosomal positioning of cohesin is controlled by transcription, and the complex also localizes to stalled replication forks. However, the role of transcription and replication in chromosome looping remains unclear. Here, we show that reduction of chromosome-bound RNA polymerase weakens normal cohesin loop extrusion boundaries, allowing cohesin to form new long-range chromosome cis interactions. Stress response genes induced by transcription inhibition are also shown to act as new loop extrusion boundaries. Furthermore, cohesin loop extrusion during early S phase is jointly controlled by transcription and replication units. Together, the results reveal that replication and transcription machineries are chromosome-folding regulators that block the progression of loop-extruding cohesin, opening for new perspectives on cohesin's roles in genome function and stability.
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Affiliation(s)
- Kristian Jeppsson
- Karolinska Institutet, Department of Biosciences and Nutrition, Neo, Hälsovägen 7c, 141 83 Huddinge, Sweden
- Karolinska Institutet, Department of Cell and Molecular Biology, Biomedicum, Tomtebodavägen 16, 171 77 Stockholm, Sweden
- Institute for Quantitative Bioscience, Tokyo University, 1-1-1, Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan
| | - Toyonori Sakata
- Institute for Quantitative Bioscience, Tokyo University, 1-1-1, Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan
| | - Ryuichiro Nakato
- Institute for Quantitative Bioscience, Tokyo University, 1-1-1, Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan
| | - Stefina Milanova
- Karolinska Institutet, Department of Biosciences and Nutrition, Neo, Hälsovägen 7c, 141 83 Huddinge, Sweden
- Karolinska Institutet, Department of Cell and Molecular Biology, Biomedicum, Tomtebodavägen 16, 171 77 Stockholm, Sweden
| | - Katsuhiko Shirahige
- Institute for Quantitative Bioscience, Tokyo University, 1-1-1, Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan
| | - Camilla Björkegren
- Karolinska Institutet, Department of Biosciences and Nutrition, Neo, Hälsovägen 7c, 141 83 Huddinge, Sweden
- Karolinska Institutet, Department of Cell and Molecular Biology, Biomedicum, Tomtebodavägen 16, 171 77 Stockholm, Sweden
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11
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CCAR2 controls mitotic progression through spatiotemporal regulation of Aurora B. Cell Death Dis 2022; 13:534. [PMID: 35672287 PMCID: PMC9174277 DOI: 10.1038/s41419-022-04990-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 05/27/2022] [Accepted: 05/30/2022] [Indexed: 01/21/2023]
Abstract
CCAR2 (cell cycle and apoptosis regulator 2) is a multifaceted protein involved in cell survival and death following cytotoxic stress. However, little is known about the physiological functions of CCAR2 in regulating cell proliferation in the absence of external stimuli. The present study shows that CCAR2-deficient cells possess multilobulated nuclei, suggesting a defect in cell division. In particular, the duration of mitotic phase was perturbed. This disturbance of mitotic progression resulted from premature loss of cohesion with the centromere, and inactivation of the spindle assembly checkpoint during prometaphase and metaphase. It resulted in the formation of lagging chromosomes during anaphase, leading ultimately to the activation of the abscission checkpoint to halt cytokinesis. The CCAR2-dependent mitotic progression was related to spatiotemporal regulation of active Aurora B. In conclusion, the results suggest that CCAR2 governs mitotic events, including proper chromosome segregation and cytokinetic division, to maintain chromosomal stability.
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12
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Kawasumi R, Abe T, Psakhye I, Miyata K, Hirota K, Branzei D. Vertebrate CTF18 and DDX11 essential function in cohesion is bypassed by preventing WAPL-mediated cohesin release. Genes Dev 2021; 35:1368-1382. [PMID: 34503989 PMCID: PMC8494208 DOI: 10.1101/gad.348581.121] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Accepted: 08/16/2021] [Indexed: 01/26/2023]
Abstract
The alternative PCNA loader containing CTF18-DCC1-CTF8 facilitates sister chromatid cohesion (SCC) by poorly defined mechanisms. Here we found that in DT40 cells, CTF18 acts complementarily with the Warsaw breakage syndrome DDX11 helicase in mediating SCC and proliferation. We uncover that the lethality and cohesion defects of ctf18 ddx11 mutants are associated with reduced levels of chromatin-bound cohesin and rescued by depletion of WAPL, a cohesin-removal factor. On the contrary, high levels of ESCO1/2 acetyltransferases that acetylate cohesin to establish SCC do not rescue ctf18 ddx11 phenotypes. Notably, the tight proximity of sister centromeres and increased anaphase bridges characteristic of WAPL-depleted cells are abrogated by loss of both CTF18 and DDX11 The results reveal that vertebrate CTF18 and DDX11 collaborate to provide sufficient amounts of chromatin-loaded cohesin available for SCC generation in the presence of WAPL-mediated cohesin-unloading activity. This process modulates chromosome structure and is essential for cellular proliferation in vertebrates.
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Affiliation(s)
- Ryotaro Kawasumi
- International Foundation of Medicine (IFOM), the Fondazione Italiana per la Ricerca sul Cancro (FIRC) Institute for Molecular Oncology Foundation, Milan 20139, Italy
| | - Takuya Abe
- International Foundation of Medicine (IFOM), the Fondazione Italiana per la Ricerca sul Cancro (FIRC) Institute for Molecular Oncology Foundation, Milan 20139, Italy
- Department of Chemistry, Graduate School of Science and Engineering, Tokyo Metropolitan University, Hachioji-shi, Tokyo 192-0397, Japan
| | - Ivan Psakhye
- International Foundation of Medicine (IFOM), the Fondazione Italiana per la Ricerca sul Cancro (FIRC) Institute for Molecular Oncology Foundation, Milan 20139, Italy
| | - Keiji Miyata
- Department of Chemistry, Graduate School of Science and Engineering, Tokyo Metropolitan University, Hachioji-shi, Tokyo 192-0397, Japan
| | - Kouji Hirota
- Department of Chemistry, Graduate School of Science and Engineering, Tokyo Metropolitan University, Hachioji-shi, Tokyo 192-0397, Japan
| | - Dana Branzei
- International Foundation of Medicine (IFOM), the Fondazione Italiana per la Ricerca sul Cancro (FIRC) Institute for Molecular Oncology Foundation, Milan 20139, Italy
- Istituto di Genetica Molecolare, Consiglio Nazionale delle Ricerche (IGM-CNR), Pavia 27100, Italy
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13
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A novel role for Dun1 in the regulation of origin firing upon hyper-acetylation of H3K56. PLoS Genet 2021; 17:e1009391. [PMID: 33600490 PMCID: PMC7924802 DOI: 10.1371/journal.pgen.1009391] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Revised: 03/02/2021] [Accepted: 02/01/2021] [Indexed: 01/27/2023] Open
Abstract
During DNA replication newly synthesized histones are incorporated into the chromatin of the replicating sister chromatids. In the yeast Saccharomyces cerevisiae new histone H3 molecules are acetylated at lysine 56. This modification is carefully regulated during the cell cycle, and any disruption of this process is a source of genomic instability. Here we show that the protein kinase Dun1 is necessary in order to maintain viability in the absence of the histone deacetylases Hst3 and Hst4, which remove the acetyl moiety from histone H3. This lethality is not due to the well-characterized role of Dun1 in upregulating dNTPs, but rather because Dun1 is needed in order to counteract the checkpoint kinase Rad53 (human CHK2) that represses the activity of late firing origins. Deletion of CTF18, encoding the large subunit of an alternative RFC-like complex (RLC), but not of components of the Elg1 or Rad24 RLCs, is enough to overcome the dependency of cells with hyper-acetylated histones on Dun1. We show that the detrimental function of Ctf18 depends on its interaction with the leading strand polymerase, Polε. Our results thus show that the main problem of cells with hyper-acetylated histones is the regulation of their temporal and replication programs, and uncover novel functions for the Dun1 protein kinase and the Ctf18 clamp loader. Within the cell’s nucleus the DNA is wrapped around proteins called histones. Upon DNA replication, newly synthesized H3 histones are acetylated at lysine 56. This acetylation is significant for the cell because when it is not removed in a timely manner it leads to genomic instability. We have investigated the source of this instability and discovered that the kinase Dun1, usually implicated in the regulation of dNTPs, the building blocks of DNA, has a novel, dNTP-independent, essential role when histones are hyper-acetylated. The essential role of Dun1 is in the regulation of the temporal program of DNA replication. Thus, our results uncover what the main defect is in cells unable to regulate the acetylation of histones, while revealing new functions for well-characterized proteins with roles in genome stability maintenance.
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14
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Abstract
Cohesin helps mediate sister chromatid cohesion, chromosome condensation, DNA repair, and transcription regulation. We exploited proximity-dependent labeling to define the in vivo interactions of cohesin domains with DNA or with other cohesin domains that lie within the same or in different cohesin complexes. Our results suggest that both cohesin's head and hinge domains are proximal to DNA, and cohesin structure is dynamic with differential folding of its coiled coil regions to generate butterfly confirmations. This method also reveals that cohesins form ordered clusters on and off DNA. The levels of cohesin clusters and their distribution on chromosomes are cell cycle-regulated. Cohesin clustering is likely necessary for cohesion maintenance because clustering and maintenance uniquely require the same subset of cohesin domains and the auxiliary cohesin factor Pds5p. These conclusions provide important new mechanistic and biological insights into the architecture of the cohesin complex, cohesin-cohesin interactions, and cohesin's tethering and loop-extruding activities.
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Affiliation(s)
- Siheng Xiang
- Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
| | - Douglas Koshland
- Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
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15
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Wu PS, Enervald E, Joelsson A, Palmberg C, Rutishauser D, Hällberg BM, Ström L. Post-translational Regulation of DNA Polymerase η, a Connection to Damage-Induced Cohesion in Saccharomyces cerevisiae. Genetics 2020; 216:1009-1022. [PMID: 33033113 PMCID: PMC7768261 DOI: 10.1534/genetics.120.303494] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 10/06/2020] [Indexed: 12/11/2022] Open
Abstract
Double-strand breaks that are induced postreplication trigger establishment of damage-induced cohesion in Saccharomyces cerevisiae, locally at the break site and genome-wide on undamaged chromosomes. The translesion synthesis polymerase, polymerase η, is required for generation of damage-induced cohesion genome-wide. However, its precise role and regulation in this process is unclear. Here, we investigated the possibility that the cyclin-dependent kinase Cdc28 and the acetyltransferase Eco1 modulate polymerase η activity. Through in vitro phosphorylation and structure modeling, we showed that polymerase η is an attractive substrate for Cdc28 Mutation of the putative Cdc28-phosphorylation site Ser14 to Ala not only affected polymerase η protein level, but also prevented generation of damage-induced cohesion in vivo We also demonstrated that Eco1 acetylated polymerase η in vitro Certain nonacetylatable polymerase η mutants showed reduced protein level, deficient nuclear accumulation, and increased ultraviolet irradiation sensitivity. In addition, we found that both Eco1 and subunits of the cohesin network are required for cell survival after ultraviolet irradiation. Our findings support functionally important Cdc28-mediated phosphorylation, as well as post-translational modifications of multiple lysine residues that modulate polymerase η activity, and provide new insights into understanding the regulation of polymerase η for damage-induced cohesion.
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Affiliation(s)
- Pei-Shang Wu
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm SE-171 77, Sweden
| | - Elin Enervald
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm SE-171 77, Sweden
| | - Angelica Joelsson
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm SE-171 77, Sweden
| | - Carina Palmberg
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm SE-171 77, Sweden
| | - Dorothea Rutishauser
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm SE-171 77, Sweden
| | - B Martin Hällberg
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm SE-171 77, Sweden
| | - Lena Ström
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm SE-171 77, Sweden
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16
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Costantino L, Hsieh THS, Lamothe R, Darzacq X, Koshland D. Cohesin residency determines chromatin loop patterns. eLife 2020; 9:e59889. [PMID: 33170773 PMCID: PMC7655110 DOI: 10.7554/elife.59889] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Accepted: 10/22/2020] [Indexed: 12/30/2022] Open
Abstract
The organization of chromatin into higher order structures is essential for chromosome segregation, the repair of DNA-damage, and the regulation of gene expression. Using Micro-C XL to detect chromosomal interactions, we observed the pervasive presence of cohesin-dependent loops with defined positions throughout the genome of budding yeast, as seen in mammalian cells. In early S phase, cohesin stably binds to cohesin associated regions (CARs) genome-wide. Subsequently, positioned loops accumulate with CARs at the bases of the loops. Cohesin regulators Wpl1 and Pds5 alter the levels and distribution of cohesin at CARs, changing the pattern of positioned loops. From these observations, we propose that cohesin with loop extrusion activity is stopped by preexisting CAR-bound cohesins, generating positioned loops. The patterns of loops observed in a population of wild-type and mutant cells can be explained by this mechanism, coupled with a heterogeneous residency of cohesin at CARs in individual cells.
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Affiliation(s)
- Lorenzo Costantino
- Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
| | - Tsung-Han S Hsieh
- Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
| | - Rebecca Lamothe
- Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
| | - Xavier Darzacq
- Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
| | - Douglas Koshland
- Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
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17
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Abstract
The organization of chromatin into higher order structures is essential for chromosome segregation, the repair of DNA-damage, and the regulation of gene expression. Using Micro-C XL to detect chromosomal interactions, we observed the pervasive presence of cohesin-dependent loops with defined positions throughout the genome of budding yeast, as seen in mammalian cells. In early S phase, cohesin stably binds to cohesin associated regions (CARs) genome-wide. Subsequently, positioned loops accumulate with CARs at the bases of the loops. Cohesin regulators Wpl1 and Pds5 alter the levels and distribution of cohesin at CARs, changing the pattern of positioned loops. From these observations, we propose that cohesin with loop extrusion activity is stopped by preexisting CAR-bound cohesins, generating positioned loops. The patterns of loops observed in a population of wild-type and mutant cells can be explained by this mechanism, coupled with a heterogeneous residency of cohesin at CARs in individual cells.
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Affiliation(s)
- Lorenzo Costantino
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Tsung-Han S Hsieh
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Rebecca Lamothe
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Xavier Darzacq
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Douglas Koshland
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
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18
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Zuilkoski CM, Skibbens RV. PCNA antagonizes cohesin-dependent roles in genomic stability. PLoS One 2020; 15:e0235103. [PMID: 33075068 PMCID: PMC7571713 DOI: 10.1371/journal.pone.0235103] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Accepted: 10/04/2020] [Indexed: 12/23/2022] Open
Abstract
PCNA sliding clamp binds factors through which histone deposition, chromatin remodeling, and DNA repair are coupled to DNA replication. PCNA also directly binds Eco1/Ctf7 acetyltransferase, which in turn activates cohesins and establishes cohesion between nascent sister chromatids. While increased recruitment thus explains the mechanism through which elevated levels of chromatin-bound PCNA rescue eco1 mutant cell growth, the mechanism through which PCNA instead worsens cohesin mutant cell growth remains unknown. Possibilities include that elevated levels of long-lived chromatin-bound PCNA reduce either cohesin deposition onto DNA or cohesin acetylation. Instead, our results reveal that PCNA increases the levels of both chromatin-bound cohesin and cohesin acetylation. Beyond sister chromatid cohesion, PCNA also plays a critical role in genomic stability such that high levels of chromatin-bound PCNA elevate genotoxic sensitivities and recombination rates. At a relatively modest increase of chromatin-bound PCNA, however, fork stability and progression appear normal in wildtype cells. Our results reveal that even a moderate increase of PCNA indeed sensitizes cohesin mutant cells to DNA damaging agents and in a process that involves the DNA damage response kinase Mec1(ATR), but not Tel1(ATM). These and other findings suggest that PCNA mis-regulation results in genome instabilities that normally are resolved by cohesin. Elevating levels of chromatin-bound PCNA may thus help target cohesinopathic cells linked that are linked to cancer.
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Affiliation(s)
- Caitlin M. Zuilkoski
- Department of Biological Sciences, Lehigh University, Bethlehem, Pennsylvania, United States of America
| | - Robert V. Skibbens
- Department of Biological Sciences, Lehigh University, Bethlehem, Pennsylvania, United States of America
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19
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Zuilkoski CM, Skibbens RV. PCNA promotes context-specific sister chromatid cohesion establishment separate from that of chromatin condensation. Cell Cycle 2020; 19:2436-2450. [PMID: 32926661 PMCID: PMC7553509 DOI: 10.1080/15384101.2020.1804221] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 07/08/2020] [Accepted: 07/24/2020] [Indexed: 10/23/2022] Open
Abstract
Cellular genomes undergo various structural changes that include cis tethering (the tethering together of two loci within a single DNA molecule), which promotes chromosome condensation and transcriptional activation, and trans tethering (the tethering together of two DNA molecules), which promotes sister chromatid cohesion and DNA repair. The protein complex termed cohesin promotes both cis and trans forms of DNA tethering, but the extent to which these cohesin functions occur in temporally or spatially defined contexts remains largely unknown. Prior studies indicate that DNA polymerase sliding clamp PCNA recruits cohesin acetyltransferase Eco1, suggesting that sister chromatid cohesion is established in the context of the DNA replication fork. In support of this model, elevated levels of PCNA rescue the temperature growth and cohesion defects exhibited by eco1 mutant cells. Here, we test whether Eco1-dependent chromatin condensation is also promoted in the context of this DNA replication fork component. Our results reveal that overexpressed PCNA does not promote DNA condensation in eco1 mutant cells, even though Smc3 acetylation levels are increased. We further provide evidence that replication fork-associated E3 ligase impacts on Eco1 are more complex that previously described. In combination, the data suggests that Eco1 acetylates Smc3 and thus promotes sister chromatid cohesion in context of the DNA replication fork, whereas a distinct cohesin population participates in chromatin condensation outside the context of the DNA replication fork.
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Affiliation(s)
- Caitlin M. Zuilkoski
- Department of Biological Sciences, Lehigh University, 18015, Bethlehem, Pennsylvania, USA
| | - Robert V. Skibbens
- Department of Biological Sciences, Lehigh University, 18015, Bethlehem, Pennsylvania, USA
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20
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Paldi F, Alver B, Robertson D, Schalbetter SA, Kerr A, Kelly DA, Baxter J, Neale MJ, Marston AL. Convergent genes shape budding yeast pericentromeres. Nature 2020; 582:119-123. [PMID: 32494069 PMCID: PMC7279958 DOI: 10.1038/s41586-020-2244-6] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Accepted: 02/25/2020] [Indexed: 11/08/2022]
Abstract
The three-dimensional architecture of the genome governs its maintenance, expression and transmission. The cohesin protein complex organizes the genome by topologically linking distant loci, and is highly enriched in specialized chromosomal domains surrounding centromeres, called pericentromeres1-6. Here we report the three-dimensional structure of pericentromeres in budding yeast (Saccharomyces cerevisiae) and establish the relationship between genome organization and function. We find that convergent genes mark pericentromere borders and, together with core centromeres, define their structure and function by positioning cohesin. Centromeres load cohesin, and convergent genes at pericentromere borders trap it. Each side of the pericentromere is organized into a looped conformation, with border convergent genes at the base. Microtubule attachment extends a single pericentromere loop, size-limited by convergent genes at its borders. Reorienting genes at borders into a tandem configuration repositions cohesin, enlarges the pericentromere and impairs chromosome biorientation during mitosis. Thus, the linear arrangement of transcriptional units together with targeted cohesin loading shapes pericentromeres into a structure that is competent for chromosome segregation. Our results reveal the architecture of the chromosomal region within which kinetochores are embedded, as well as the restructuring caused by microtubule attachment. Furthermore, we establish a direct, causal relationship between the three-dimensional genome organization of a specific chromosomal domain and cellular function.
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Affiliation(s)
- Flora Paldi
- The Wellcome Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | - Bonnie Alver
- The Wellcome Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | - Daniel Robertson
- The Wellcome Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | | | - Alastair Kerr
- The Wellcome Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | - David A Kelly
- The Wellcome Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | - Jonathan Baxter
- Genome Damage and Stability Centre, University of Sussex, Brighton, UK
| | - Matthew J Neale
- Genome Damage and Stability Centre, University of Sussex, Brighton, UK
| | - Adele L Marston
- The Wellcome Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, UK.
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21
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Liu HW, Bouchoux C, Panarotto M, Kakui Y, Patel H, Uhlmann F. Division of Labor between PCNA Loaders in DNA Replication and Sister Chromatid Cohesion Establishment. Mol Cell 2020; 78:725-738.e4. [PMID: 32277910 PMCID: PMC7242910 DOI: 10.1016/j.molcel.2020.03.017] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 12/17/2019] [Accepted: 03/10/2020] [Indexed: 01/26/2023]
Abstract
Concomitant with DNA replication, the chromosomal cohesin complex establishes cohesion between newly replicated sister chromatids. Several replication-fork-associated "cohesion establishment factors," including the multifunctional Ctf18-RFC complex, aid this process in as yet unknown ways. Here, we show that Ctf18-RFC's role in sister chromatid cohesion correlates with PCNA loading but is separable from its role in the replication checkpoint. Ctf18-RFC loads PCNA with a slight preference for the leading strand, which is dispensable for DNA replication. Conversely, the canonical Rfc1-RFC complex preferentially loads PCNA onto the lagging strand, which is crucial for DNA replication but dispensable for sister chromatid cohesion. The downstream effector of Ctf18-RFC is cohesin acetylation, which we place toward a late step during replication maturation. Our results suggest that Ctf18-RFC enriches and balances PCNA levels at the replication fork, beyond the needs of DNA replication, to promote establishment of sister chromatid cohesion and possibly other post-replicative processes.
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Affiliation(s)
- Hon Wing Liu
- Chromosome Segregation Laboratory, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Céline Bouchoux
- Chromosome Segregation Laboratory, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Mélanie Panarotto
- Chromosome Segregation Laboratory, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Yasutaka Kakui
- Chromosome Segregation Laboratory, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Harshil Patel
- Bioinformatics and Biostatistics Science Technology Platform, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Frank Uhlmann
- Chromosome Segregation Laboratory, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK.
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22
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Benedict B, van Schie JJM, Oostra AB, Balk JA, Wolthuis RMF, Riele HT, de Lange J. WAPL-Dependent Repair of Damaged DNA Replication Forks Underlies Oncogene-Induced Loss of Sister Chromatid Cohesion. Dev Cell 2020; 52:683-698.e7. [PMID: 32084359 DOI: 10.1016/j.devcel.2020.01.024] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 11/19/2019] [Accepted: 01/22/2020] [Indexed: 12/22/2022]
Abstract
Premature loss of sister chromatid cohesion at metaphase is a diagnostic marker for different cohesinopathies. Here, we report that metaphase spreads of many cancer cell lines also show premature loss of sister chromatid cohesion. Cohesion loss occurs independently of mutations in cohesion factors including SA2, a cohesin subunit frequently inactivated in cancer. In untransformed cells, induction of DNA replication stress by activation of oncogenes or inhibition of DNA replication is sufficient to trigger sister chromatid cohesion loss. Importantly, cell growth under conditions of replication stress requires the cohesin remover WAPL. WAPL promotes rapid RAD51-dependent repair and restart of broken replication forks. We propose that active removal of cohesin allows cancer cells to overcome DNA replication stress. This leads to oncogene-induced cohesion loss from newly synthesized sister chromatids that may contribute to genomic instability and likely represents a targetable cancer cell vulnerability.
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Affiliation(s)
- Bente Benedict
- Netherlands Cancer Institute, Division of Tumor Biology and Immunology, Amsterdam, the Netherlands
| | - Janne J M van Schie
- Cancer Center Amsterdam, Department of Clinical Genetics, section Oncogenetics, Amsterdam University Medical Centers, Amsterdam, the Netherlands
| | - Anneke B Oostra
- Cancer Center Amsterdam, Department of Clinical Genetics, section Oncogenetics, Amsterdam University Medical Centers, Amsterdam, the Netherlands
| | - Jesper A Balk
- Cancer Center Amsterdam, Department of Clinical Genetics, section Oncogenetics, Amsterdam University Medical Centers, Amsterdam, the Netherlands
| | - Rob M F Wolthuis
- Cancer Center Amsterdam, Department of Clinical Genetics, section Oncogenetics, Amsterdam University Medical Centers, Amsterdam, the Netherlands.
| | - Hein Te Riele
- Netherlands Cancer Institute, Division of Tumor Biology and Immunology, Amsterdam, the Netherlands.
| | - Job de Lange
- Cancer Center Amsterdam, Department of Clinical Genetics, section Oncogenetics, Amsterdam University Medical Centers, Amsterdam, the Netherlands.
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23
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Shen D, Skibbens RV. Promotion of Hyperthermic-Induced rDNA Hypercondensation in Saccharomyces cerevisiae. Genetics 2020; 214:589-604. [PMID: 31980450 PMCID: PMC7054013 DOI: 10.1534/genetics.119.302994] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Accepted: 12/29/2019] [Indexed: 12/11/2022] Open
Abstract
Ribosome biogenesis is tightly regulated through stress-sensing pathways that impact genome stability, aging and senescence. In Saccharomyces cerevisiae, ribosomal RNAs are transcribed from rDNA located on the right arm of chromosome XII. Numerous studies reveal that rDNA decondenses into a puff-like structure during interphase, and condenses into a tight loop-like structure during mitosis. Intriguingly, a novel and additional mechanism of increased mitotic rDNA compaction (termed hypercondensation) was recently discovered that occurs in response to temperature stress (hyperthermic-induced) and is rapidly reversible. Here, we report that neither changes in condensin binding or release of DNA during mitosis, nor mutation of factors that regulate cohesin binding and release, appear to play a critical role in hyperthermic-induced rDNA hypercondensation. A candidate genetic approach revealed that deletion of either HSP82 or HSC82 (Hsp90 encoding heat shock paralogs) result in significantly reduced hyperthermic-induced rDNA hypercondensation. Intriguingly, Hsp inhibitors do not impact rDNA hypercondensation. In combination, these findings suggest that Hsp90 either stabilizes client proteins, which are sensitive to very transient thermic challenges, or directly promotes rDNA hypercondensation during preanaphase. Our findings further reveal that the high mobility group protein Hmo1 is a negative regulator of mitotic rDNA condensation, distinct from its role in promoting premature condensation of rDNA during interphase upon nutrient starvation.
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Affiliation(s)
- Donglai Shen
- Department of Biological Sciences, Lehigh University, Bethlehem, Pennsylvania 18015
| | - Robert V Skibbens
- Department of Biological Sciences, Lehigh University, Bethlehem, Pennsylvania 18015
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24
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Liu W, Biton E, Pathania A, Matityahu A, Irudayaraj J, Onn I. Monomeric cohesin state revealed by live-cell single-molecule spectroscopy. EMBO Rep 2020; 21:e48211. [PMID: 31886609 PMCID: PMC7001500 DOI: 10.15252/embr.201948211] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 11/28/2019] [Accepted: 12/04/2019] [Indexed: 12/17/2022] Open
Abstract
The cohesin complex plays an important role in the maintenance of genome stability. Cohesin is composed of four core subunits and a set of regulatory subunits that interact with the core subunits. Less is known about cohesin dynamics in live cells and on the contribution of individual subunits to the overall complex. Understanding the tethering mechanism of cohesin is still a challenge, especially because the proposed mechanisms are still not conclusive. Models proposed to describe tethering depend on either the monomeric cohesin ring or a cohesin dimer. Here, we investigate the role of cohesin dynamics and stoichiometry in live yeast cells at single-molecule resolution. We explore the effect of regulatory subunit deletion on cohesin mobility and found that depletion of different regulatory subunits has opposing effects. Finally, we show that cohesin exists mostly as a canonical monomer throughout the cell cycle, and its monomeric form is independent of its regulatory factors. Our results demonstrate that single-molecule tools have the potential to provide new insights into the cohesin mechanism of action in live cells.
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Affiliation(s)
- Wenjie Liu
- Department of Bioengineering, Micro and Nanotechnology LaboratoryCancer Center at IllinoisUniversity of Illinois at Urbana‐ChampaignUrbanaILUSA
- Mills Breast Cancer InstituteCarle Foundation HospitalUrbanaILUSA
| | - Elisheva Biton
- The Azrieli Faculty of MedicineBar‐Ilan UniversitySafedIsrael
| | - Anjali Pathania
- The Azrieli Faculty of MedicineBar‐Ilan UniversitySafedIsrael
| | - Avi Matityahu
- The Azrieli Faculty of MedicineBar‐Ilan UniversitySafedIsrael
| | - Joseph Irudayaraj
- Department of Bioengineering, Micro and Nanotechnology LaboratoryCancer Center at IllinoisUniversity of Illinois at Urbana‐ChampaignUrbanaILUSA
- Mills Breast Cancer InstituteCarle Foundation HospitalUrbanaILUSA
| | - Itay Onn
- The Azrieli Faculty of MedicineBar‐Ilan UniversitySafedIsrael
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25
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Birot A, Tormos-Pérez M, Vaur S, Feytout A, Jaegy J, Alonso Gil D, Vazquez S, Ekwall K, Javerzat JP. The CDK Pef1 and protein phosphatase 4 oppose each other for regulating cohesin binding to fission yeast chromosomes. eLife 2020; 9:e50556. [PMID: 31895039 PMCID: PMC6954021 DOI: 10.7554/elife.50556] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Accepted: 01/02/2020] [Indexed: 12/19/2022] Open
Abstract
Cohesin has essential roles in chromosome structure, segregation and repair. Cohesin binding to chromosomes is catalyzed by the cohesin loader, Mis4 in fission yeast. How cells fine tune cohesin deposition is largely unknown. Here, we provide evidence that Mis4 activity is regulated by phosphorylation of its cohesin substrate. A genetic screen for negative regulators of Mis4 yielded a CDK called Pef1, whose closest human homologue is CDK5. Inhibition of Pef1 kinase activity rescued cohesin loader deficiencies. In an otherwise wild-type background, Pef1 ablation stimulated cohesin binding to its regular sites along chromosomes while ablating Protein Phosphatase 4 had the opposite effect. Pef1 and PP4 control the phosphorylation state of the cohesin kleisin Rad21. The CDK phosphorylates Rad21 on Threonine 262. Pef1 ablation, non-phosphorylatable Rad21-T262 or mutations within a Rad21 binding domain of Mis4 alleviated the effect of PP4 deficiency. Such a CDK/PP4-based regulation of cohesin loader activity could provide an efficient mechanism for translating cellular cues into a fast and accurate cohesin response.
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Affiliation(s)
- Adrien Birot
- Institut de Biochimie et Génétique Cellulaires, UMR 5095 CNRS - Université de BordeauxBordeauxFrance
| | - Marta Tormos-Pérez
- Institut de Biochimie et Génétique Cellulaires, UMR 5095 CNRS - Université de BordeauxBordeauxFrance
| | - Sabine Vaur
- Institut de Biochimie et Génétique Cellulaires, UMR 5095 CNRS - Université de BordeauxBordeauxFrance
| | - Amélie Feytout
- Institut de Biochimie et Génétique Cellulaires, UMR 5095 CNRS - Université de BordeauxBordeauxFrance
| | - Julien Jaegy
- Institut de Biochimie et Génétique Cellulaires, UMR 5095 CNRS - Université de BordeauxBordeauxFrance
| | - Dácil Alonso Gil
- Institut de Biochimie et Génétique Cellulaires, UMR 5095 CNRS - Université de BordeauxBordeauxFrance
| | - Stéphanie Vazquez
- Institut de Biochimie et Génétique Cellulaires, UMR 5095 CNRS - Université de BordeauxBordeauxFrance
| | - Karl Ekwall
- Department of Biosciences and NutritionKarolinska InstitutetHuddingeSweden
| | - Jean-Paul Javerzat
- Institut de Biochimie et Génétique Cellulaires, UMR 5095 CNRS - Université de BordeauxBordeauxFrance
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26
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Thadani R, Kamenz J, Heeger S, Muñoz S, Uhlmann F. Cell-Cycle Regulation of Dynamic Chromosome Association of the Condensin Complex. Cell Rep 2019; 23:2308-2317. [PMID: 29791843 PMCID: PMC5986713 DOI: 10.1016/j.celrep.2018.04.082] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 12/15/2017] [Accepted: 04/18/2018] [Indexed: 11/16/2022] Open
Abstract
Eukaryotic cells inherit their genomes in the form of chromosomes, which are formed from the compaction of interphase chromatin by the condensin complex. Condensin is a member of the structural maintenance of chromosomes (SMC) family of ATPases, large ring-shaped protein assemblies that entrap DNA to establish chromosomal interactions. Here, we use the budding yeast Saccharomyces cerevisiae to dissect the role of the condensin ATPase and its relationship with cell-cycle-regulated chromosome binding dynamics. ATP hydrolysis-deficient condensin binds to chromosomes but is defective in chromosome condensation and segregation. By modulating the ATPase, we demonstrate that it controls condensin's dynamic turnover on chromosomes. Mitosis-specific phosphorylation of condensin's Smc4 subunit reduces the turnover rate. However, reducing turnover by itself is insufficient to compact chromosomes. We propose that condensation requires fine-tuned dynamic condensin interactions with more than one DNA. These results enhance our molecular understanding of condensin function during chromosome condensation.
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Affiliation(s)
- Rahul Thadani
- Chromosome Segregation Laboratory, The Francis Crick Institute, London NW1 1AT, UK; Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, NIH, Bethesda, MD 20892, USA
| | - Julia Kamenz
- Chromosome Segregation Laboratory, The Francis Crick Institute, London NW1 1AT, UK
| | - Sebastian Heeger
- Chromosome Segregation Laboratory, The Francis Crick Institute, London NW1 1AT, UK
| | - Sofía Muñoz
- Chromosome Segregation Laboratory, The Francis Crick Institute, London NW1 1AT, UK
| | - Frank Uhlmann
- Chromosome Segregation Laboratory, The Francis Crick Institute, London NW1 1AT, UK.
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27
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Dauban L, Kamgoué A, Wang R, Léger-Silvestre I, Beckouët F, Cantaloube S, Gadal O. Quantification of the dynamic behaviour of ribosomal DNA genes and nucleolus during yeast Saccharomyces cerevisiae cell cycle. J Struct Biol 2019; 208:152-164. [PMID: 31449968 DOI: 10.1016/j.jsb.2019.08.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Revised: 08/20/2019] [Accepted: 08/21/2019] [Indexed: 11/19/2022]
Abstract
Spatial organisation of chromosomes is a determinant of genome stability and is required for proper mitotic segregation. However, visualization of individual chromatids in living cells and quantification of their geometry, remains technically challenging. Here, we used live cell imaging to quantitate the three-dimensional conformation of yeast Saccharomyces cerevisiae ribosomal DNA (rDNA). rDNA is confined within the nucleolus and is composed of about 200 copies representing about 10% of the yeast genome. To fluorescently label rDNA in living cells, we generated a set of nucleolar proteins fused to GFP or made use of a tagged rDNA, in which lacO repetitions were inserted in each repeat unit. We could show that nucleolus is not modified in appearance, shape or size during interphase while rDNA is highly reorganized. Computationally tracing 3D rDNA paths allowed us to quantitatively assess rDNA size, shape and geometry. During interphase, rDNA was progressively reorganized from a zig-zag segmented line of small size (5,5 µm) to a long, homogeneous, line-like structure of 8,7 µm in metaphase. Most importantly, whatever the cell-cycle stage considered, rDNA fibre could be decomposed in subdomains, as previously suggested for 3D chromatin organisation. Finally, we could determine that spatial reorganisation of these subdomains and establishment of rDNA mitotic organisation is under the control of the cohesin complex.
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Affiliation(s)
- Lise Dauban
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 31000 Toulouse, France
| | - Alain Kamgoué
- Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 31000 Toulouse, France
| | - Renjie Wang
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 31000 Toulouse, France
| | - Isabelle Léger-Silvestre
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 31000 Toulouse, France
| | - Frédéric Beckouët
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 31000 Toulouse, France
| | - Sylvain Cantaloube
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 31000 Toulouse, France
| | - Olivier Gadal
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 31000 Toulouse, France.
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28
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Challa K, Shinohara M, Shinohara A. Meiotic prophase-like pathway for cleavage-independent removal of cohesin for chromosome morphogenesis. Curr Genet 2019; 65:817-827. [PMID: 30923890 DOI: 10.1007/s00294-019-00959-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 03/20/2019] [Accepted: 03/20/2019] [Indexed: 12/11/2022]
Abstract
Sister chromatid cohesion is essential for chromosome segregation both in mitosis and meiosis. Cohesion between two chromatids is mediated by a protein complex called cohesin. The loading and unloading of the cohesin are tightly regulated during the cell cycle. In vertebrate cells, cohesin is released from chromosomes by two distinct pathways. The best characterized pathway occurs at the onset of anaphase, when the kleisin component of the cohesin is destroyed by a protease, separase. The cleavage of the cohesin by separase releases entrapped sister chromatids allowing anaphase to commence. In addition, prior to the metaphase-anaphase transition, most of cohesin is removed from chromosomes in a cleavage-independent manner. This cohesin release is referred to as the prophase pathway. In meiotic cells, sister chromatid cohesion is essential for the segregation of homologous chromosomes during meiosis I. Thus, it was assumed that the prophase pathway for cohesin removal from chromosome arms would be suppressed during meiosis to avoid errors in chromosome segregation. However, recent studies revealed the presence of a meiosis-specific prophase-like pathway for cleavage-independent removal of cohesin during late prophase I in different organisms. In budding yeast, the cleavage-independent removal of cohesin is mediated through meiosis-specific phosphorylation of cohesin subunits, Rec8, the meiosis-specific kleisin, and the yeast Wapl ortholog, Rad61/Wpl1. This pathway plays a role in chromosome morphogenesis during late prophase I, promoting chromosome compaction. In this review, we give an overview of the prophase pathway for cohesin dynamics during meiosis, which has a complex regulation leading to differentially localized populations of cohesin along meiotic chromosomes.
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Affiliation(s)
- Kiran Challa
- Institute for Protein Research, Osaka University, Suita, Osaka, 565-0871, Japan
- Friedrich Miescher Institute for Biomedical Research, CH-4058, Basel, Switzerland
| | - Miki Shinohara
- Institute for Protein Research, Osaka University, Suita, Osaka, 565-0871, Japan
- Graduate School of Agriculture, Kindai University, Nara, 631-8505, Japan
| | - Akira Shinohara
- Institute for Protein Research, Osaka University, Suita, Osaka, 565-0871, Japan.
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Srinivasan M, Petela NJ, Scheinost JC, Collier J, Voulgaris M, B Roig M, Beckouët F, Hu B, Nasmyth KA. Scc2 counteracts a Wapl-independent mechanism that releases cohesin from chromosomes during G1. eLife 2019; 8:e44736. [PMID: 31225797 PMCID: PMC6588348 DOI: 10.7554/elife.44736] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Accepted: 05/30/2019] [Indexed: 12/23/2022] Open
Abstract
Cohesin's association with chromosomes is determined by loading dependent on the Scc2/4 complex and release due to Wapl. We show here that Scc2 also actively maintains cohesin on chromosomes during G1 in S. cerevisiae cells. It does so by blocking a Wapl-independent release reaction that requires opening the cohesin ring at its Smc3/Scc1 interface as well as the D loop of Smc1's ATPase. The Wapl-independent release mechanism is switched off as cells activate Cdk1 and enter G2/M and cannot be turned back on without cohesin's dissociation from chromosomes. The latter phenomenon enabled us to show that in the absence of release mechanisms, cohesin rings that have already captured DNA in a Scc2-dependent manner before replication no longer require Scc2 to capture sister DNAs during S phase.
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Affiliation(s)
| | - Naomi J Petela
- Department of BiochemistryUniversity of OxfordOxfordUnited Kingdom
| | | | - James Collier
- Department of BiochemistryUniversity of OxfordOxfordUnited Kingdom
| | | | - Maurici B Roig
- Department of BiochemistryUniversity of OxfordOxfordUnited Kingdom
| | - Frederic Beckouët
- Laboratoire de Biologie Moléculaire EucaryoteCentre de Biologie Intégrative (CBI), Université de ToulouseToulouseFrance
| | - Bin Hu
- Department of Molecular Biology and BiotechnologyUniversity of SheffieldSheffieldUnited Kingdom
| | - Kim A Nasmyth
- Department of BiochemistryUniversity of OxfordOxfordUnited Kingdom
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30
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Guacci V, Chatterjee F, Robison B, Koshland DE. Communication between distinct subunit interfaces of the cohesin complex promotes its topological entrapment of DNA. eLife 2019; 8:e46347. [PMID: 31162048 PMCID: PMC6579514 DOI: 10.7554/elife.46347] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 06/04/2019] [Indexed: 12/21/2022] Open
Abstract
Cohesin mediates higher order chromosome structure. Its biological activities require topological entrapment of DNA within a lumen(s) formed by cohesin subunits. The reversible dissociation of cohesin's Smc3p and Mcd1p subunits is postulated to form a regulated gate that allows DNA entry and exit into the lumen. We assessed gate-independent functions of this interface in yeast using a fusion protein that joins Smc3p to Mcd1p. We show that in vivo all the regulators of cohesin promote DNA binding of cohesin by mechanisms independent of opening this gate. Furthermore, we show that this interface has a gate-independent activity essential for cohesin to bind chromosomes. We propose that this interface regulates DNA entrapment by controlling the opening and closing of one or more distal interfaces formed by cohesin subunits, likely by inducing a conformation change in cohesin. Furthermore, cohesin regulators modulate the interface to control both DNA entrapment and cohesin functions after DNA binding.
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Affiliation(s)
- Vincent Guacci
- Department of Molecular and Cell BiologyUniversity of California, BerkeleyBerkeleyUnited States
| | - Fiona Chatterjee
- Department of Molecular and Cell BiologyUniversity of California, BerkeleyBerkeleyUnited States
| | - Brett Robison
- Department of Molecular and Cell BiologyUniversity of California, BerkeleyBerkeleyUnited States
| | - Douglas E Koshland
- Department of Molecular and Cell BiologyUniversity of California, BerkeleyBerkeleyUnited States
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31
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Nishiyama T. Cohesion and cohesin-dependent chromatin organization. Curr Opin Cell Biol 2019; 58:8-14. [PMID: 30544080 DOI: 10.1016/j.ceb.2018.11.006] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2018] [Accepted: 11/29/2018] [Indexed: 02/08/2023]
Abstract
Cohesin, one of structural maintenance of chromosomes (SMC) complexes, forms a ring-shaped protein complex, and mediates sister chromatid cohesion for accurate chromosome segregation and precise genome inheritance. The cohesin ring entraps one or two DNA molecules to achieve cohesion, which is further regulated by cohesin-binding proteins and modification enzymes in a cell cycle-dependent manner. Recent significant advancements in Hi-C technologies have revealed numerous cohesin-dependent higher-order chromatin structures. Simultaneously, single-molecule imaging has also unveiled the detailed dynamics of cohesin on DNA and/or chromatin. Thus, those studies are providing novel visions for the authentic chromatin structure regulated by cohesin.
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Affiliation(s)
- Tomoko Nishiyama
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Japan.
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32
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Hong S, Joo JH, Yun H, Kim K. The nature of meiotic chromosome dynamics and recombination in budding yeast. J Microbiol 2019; 57:221-231. [PMID: 30671743 DOI: 10.1007/s12275-019-8541-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Revised: 10/24/2018] [Accepted: 10/26/2018] [Indexed: 12/28/2022]
Abstract
During meiosis, crossing over allows for the exchange of genes between homologous chromosomes, enabling their segregation and leading to genetic variation in the resulting gametes. Spo11, a topoisomerase-like protein expressed in eukaryotes, and diverse accessory factors induce programmed double-strand breaks (DSBs) to initiate meiotic recombination during the early phase of meiosis after DNA replication. DSBs are further repaired via meiosis-specific homologous recombination. Studies on budding yeast have provided insights into meiosis and genetic recombination and have improved our understanding of higher eukaryotic systems. Cohesin, a chromosome-associated multiprotein complex, mediates sister chromatid cohesion (SCC), and is conserved from yeast to humans. Diverse cohesin subunits in budding yeast have been identified in DNA metabolic pathways, such as DNA replication, chromosome segregation, recombination, DNA repair, and gene regulation. During cell cycle, SCC is established by multiple cohesin subunits, which physically bind sister chromatids together and modulate proteins that involve in the capturing and separation of sister chromatids. Cohesin components include at least four core subunits that establish and maintain SCC: two structural maintenance chromosome subunits (Smc1 and Smc3), an α-kleisin subunit (Mcd1/Scc1 during mitosis and Rec8 during meiosis), and Scc3/Irr1 (SA1 and SA2). In addition, the cohesin-associated factors Pds5 and Rad61 regulate structural modifications and cell cyclespecific dynamics of chromatin to ensure accurate chromosome segregation. In this review, we discuss SCC and the recombination pathway, as well as the relationship between the two processes in budding yeast, and we suggest a possible conserved mechanism for meiotic chromosome dynamics from yeast to humans.
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Affiliation(s)
- Soogil Hong
- Department of Life Science, Chung-Ang University, Seoul, 06974, Republic of Korea
| | - Jeong Hwan Joo
- Department of Life Science, Chung-Ang University, Seoul, 06974, Republic of Korea
| | - Hyeseon Yun
- Department of Life Science, Chung-Ang University, Seoul, 06974, Republic of Korea
| | - Keunpil Kim
- Department of Life Science, Chung-Ang University, Seoul, 06974, Republic of Korea.
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33
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Meiosis-specific prophase-like pathway controls cleavage-independent release of cohesin by Wapl phosphorylation. PLoS Genet 2019; 15:e1007851. [PMID: 30605471 PMCID: PMC6317811 DOI: 10.1371/journal.pgen.1007851] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 11/25/2018] [Indexed: 01/09/2023] Open
Abstract
Sister chromatid cohesion on chromosome arms is essential for the segregation of homologous chromosomes during meiosis I while it is dispensable for sister chromatid separation during mitosis. It was assumed that, unlike the situation in mitosis, chromosome arms retain cohesion prior to onset of anaphase-I. Paradoxically, reduced immunostaining signals of meiosis-specific cohesin, including the kleisin Rec8, were observed on chromosomes during late prophase-I of budding yeast. This decrease is seen in the absence of Rec8 cleavage and depends on condensin-mediated recruitment of Polo-like kinase (PLK/Cdc5). In this study, we confirmed that this release indeed accompanies the dissociation of acetylated Smc3 as well as Rec8 from meiotic chromosomes during late prophase-I. This release requires, in addition to PLK, the cohesin regulator, Wapl (Rad61/Wpl1 in yeast), and Dbf4-dependent Cdc7 kinase (DDK). Meiosis-specific phosphorylation of Rad61/Wpl1 and Rec8 by PLK and DDK collaboratively promote this release. This process is similar to the vertebrate “prophase” pathway for cohesin release during G2 phase and pro-metaphase. In yeast, meiotic cohesin release coincides with PLK-dependent compaction of chromosomes in late meiotic prophase-I. We suggest that yeast uses this highly regulated cleavage-independent pathway to remove cohesin during late prophase-I to facilitate morphogenesis of condensed metaphase-I chromosomes. In meiosis the life and health of future generations is decided upon. Any failure in chromosome segregation has a detrimental impact. Therefore, it is currently believed that the physical connections between homologous chromosomes are maintained by meiotic cohesin with exceptional stability. Indeed, it was shown that cohesive cohesin does not show an appreciable turnover during long periods in oocyte development. In this context, it was long assumed but not properly investigated, that the prophase pathway for cohesin release would be specific to mitosis and would be safely suppressed during meiosis so as not to endanger essential connections between chromosomes. However, a previous study on budding yeast meiosis suggests the presence of cleavage-independent pathway of cohesin release during late prophase-I. In the work presented here we confirmed that the prophase pathway is not suppressed during meiosis, at least in budding yeast and showed that this cleavage-independent release is regulated by meiosis-specific phosphorylation of two cohesin subunits, Rec8 and Rad61(Wapl) by two cell-cycle regulators, PLK and DDK. Our results suggest that late meiotic prophase-I actively controls cohesin dynamics on meiotic chromosomes for chromosome segregation.
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Villa-Hernández S, Bermejo R. Cohesin dynamic association to chromatin and interfacing with replication forks in genome integrity maintenance. Curr Genet 2018; 64:1005-1013. [PMID: 29549581 DOI: 10.1007/s00294-018-0824-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Revised: 03/12/2018] [Accepted: 03/13/2018] [Indexed: 01/09/2023]
Abstract
Proliferating cells need to accurately duplicate and pass their genetic material on to daughter cells. Problems during replication and partition challenge the structural and numerical integrity of chromosomes. Diverse mechanisms, as the DNA replication checkpoint, survey the correct progression of replication and couple it with other cell cycle events to preserve genome integrity. The structural maintenance of chromosomes (SMC) cohesin complex primarily contributes to chromosome duplication by mediating the tethering of newly replicated sister chromatids, thus assisting their equal segregation in mitosis. In addition, cohesin exerts important functions in genome organization, gene expression and DNA repair. These are determined by cohesin's ability to bring together different DNA segments and, hence, by the fashion and dynamics of its interaction with chromatin. It recently emerged that cohesin contributes to the protection of stalled replication forks through a mechanism requiring its timely mobilization from unreplicated DNA and relocation to nascent strands. This mechanism relies on DNA replication checkpoint-dependent cohesin ubiquitylation and promotes nascent sister chromatid entrapment, likely contributing to preserve stalled replisome-fork architectural integrity. Here we review how cohesin dynamic association to chromatin is controlled through post-translational modifications to dictate its functions during chromosome duplication. We also discuss recent insights on the mechanism that mediates interfacing of replisome components with chromatin-bound cohesin and its contribution to the establishment of sister chromatid cohesion and the protection of stalled replication forks.
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Affiliation(s)
- Sara Villa-Hernández
- Centro de Investigaciones Biológicas (CIB-CSIC), Calle Ramiro de Maeztu 9, 28040, Madrid, Spain
- Wolfson Centre for Age-Related Diseases, King's College London, London, SE1 1UL, UK
| | - Rodrigo Bermejo
- Centro de Investigaciones Biológicas (CIB-CSIC), Calle Ramiro de Maeztu 9, 28040, Madrid, Spain.
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35
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Ivanov MP, Ladurner R, Poser I, Beveridge R, Rampler E, Hudecz O, Novatchkova M, Hériché JK, Wutz G, van der Lelij P, Kreidl E, Hutchins JR, Axelsson-Ekker H, Ellenberg J, Hyman AA, Mechtler K, Peters JM. The replicative helicase MCM recruits cohesin acetyltransferase ESCO2 to mediate centromeric sister chromatid cohesion. EMBO J 2018; 37:e97150. [PMID: 29930102 PMCID: PMC6068434 DOI: 10.15252/embj.201797150] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2017] [Revised: 02/27/2018] [Accepted: 04/09/2018] [Indexed: 11/09/2022] Open
Abstract
Chromosome segregation depends on sister chromatid cohesion which is established by cohesin during DNA replication. Cohesive cohesin complexes become acetylated to prevent their precocious release by WAPL before cells have reached mitosis. To obtain insight into how DNA replication, cohesion establishment and cohesin acetylation are coordinated, we analysed the interaction partners of 55 human proteins implicated in these processes by mass spectrometry. This proteomic screen revealed that on chromatin the cohesin acetyltransferase ESCO2 associates with the MCM2-7 subcomplex of the replicative Cdc45-MCM-GINS helicase. The analysis of ESCO2 mutants defective in MCM binding indicates that these interactions are required for proper recruitment of ESCO2 to chromatin, cohesin acetylation during DNA replication, and centromeric cohesion. We propose that MCM binding enables ESCO2 to travel with replisomes to acetylate cohesive cohesin complexes in the vicinity of replication forks so that these complexes can be protected from precocious release by WAPL Our results also indicate that ESCO1 and ESCO2 have distinct functions in maintaining cohesion between chromosome arms and centromeres, respectively.
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Affiliation(s)
| | - Rene Ladurner
- Research Institute of Molecular Pathology, Vienna, Austria
| | - Ina Poser
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | | | - Evelyn Rampler
- Research Institute of Molecular Pathology, Vienna, Austria
| | - Otto Hudecz
- Institute of Molecular Biotechnology, Vienna, Austria
| | | | | | - Gordana Wutz
- Research Institute of Molecular Pathology, Vienna, Austria
| | | | - Emanuel Kreidl
- Research Institute of Molecular Pathology, Vienna, Austria
| | | | | | - Jan Ellenberg
- European Molecular Biology Laboratory, Heidelberg, Germany
| | - Anthony A Hyman
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Karl Mechtler
- Research Institute of Molecular Pathology, Vienna, Austria
- Institute of Molecular Biotechnology, Vienna, Austria
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36
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Hernandez MR, Davis MB, Jiang J, Brouhard EA, Severson AF, Csankovszki G. Condensin I protects meiotic cohesin from WAPL-1 mediated removal. PLoS Genet 2018; 14:e1007382. [PMID: 29768402 PMCID: PMC5973623 DOI: 10.1371/journal.pgen.1007382] [Citation(s) in RCA: 11] [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: 09/15/2017] [Revised: 05/29/2018] [Accepted: 04/27/2018] [Indexed: 11/22/2022] Open
Abstract
Condensin complexes are key determinants of higher-order chromatin structure and are required for mitotic and meiotic chromosome compaction and segregation. We identified a new role for condensin in the maintenance of sister chromatid cohesion during C. elegans meiosis. Using conventional and stimulated emission depletion (STED) microscopy we show that levels of chromosomally-bound cohesin were significantly reduced in dpy-28 mutants, which lack a subunit of condensin I. SYP-1, a component of the synaptonemal complex central region, was also diminished, but no decrease in the axial element protein HTP-3 was observed. Surprisingly, the two key meiotic cohesin complexes of C. elegans were both depleted from meiotic chromosomes following the loss of condensin I, and disrupting condensin I in cohesin mutants increased the frequency of detached sister chromatids. During mitosis and meiosis in many organisms, establishment of cohesion is antagonized by cohesin removal by Wapl, and we found that condensin I binds to C. elegans WAPL-1 and counteracts WAPL-1-dependent cohesin removal. Our data suggest that condensin I opposes WAPL-1 to promote stable binding of cohesin to meiotic chromosomes, thereby ensuring linkages between sister chromatids in early meiosis.
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Affiliation(s)
- Margarita R. Hernandez
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, United States of America
| | - Michael B. Davis
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, United States of America
| | - Jianhao Jiang
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, United States of America
| | - Elizabeth A. Brouhard
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, United States of America
| | - Aaron F. Severson
- Center for Gene Regulation in Health and Disease and Department of Biological, Geological and Environmental Sciences, Cleveland State University, Cleveland, OH, United States of America
| | - Györgyi Csankovszki
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, United States of America
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37
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Zheng G, Kanchwala M, Xing C, Yu H. MCM2-7-dependent cohesin loading during S phase promotes sister-chromatid cohesion. eLife 2018; 7:e33920. [PMID: 29611806 PMCID: PMC5897099 DOI: 10.7554/elife.33920] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Accepted: 03/31/2018] [Indexed: 01/13/2023] Open
Abstract
DNA replication transforms cohesin rings dynamically associated with chromatin into the cohesive form to establish sister-chromatid cohesion. Here, we show that, in human cells, cohesin loading onto chromosomes during early S phase requires the replicative helicase MCM2-7 and the kinase DDK. Cohesin and its loader SCC2/4 (NIPBL/MAU2 in humans) associate with DDK and phosphorylated MCM2-7. This binding does not require MCM2-7 activation by CDC45 and GINS, but its persistence on activated MCM2-7 requires fork-stabilizing replisome components. Inactivation of these replisome components impairs cohesin loading and causes interphase cohesion defects. Interfering with Okazaki fragment processing or nucleosome assembly does not impact cohesion. Therefore, MCM2-7-coupled cohesin loading promotes cohesion establishment, which occurs without Okazaki fragment maturation. We propose that the cohesin-loader complex bound to MCM2-7 is mobilized upon helicase activation, transiently held by the replisome, and deposited behind the replication fork to encircle sister chromatids and establish cohesion.
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Affiliation(s)
- Ge Zheng
- Howard Hughes Medical Institute, Department of PharmacologyUniversity of Texas Southwestern Medical CenterDallasUnited States
| | - Mohammed Kanchwala
- Bioinformatics Lab, Eugene McDermott Center for Human Growth and DevelopmentUniversity of Texas Southwestern Medical CenterDallasUnited States
| | - Chao Xing
- Bioinformatics Lab, Eugene McDermott Center for Human Growth and DevelopmentUniversity of Texas Southwestern Medical CenterDallasUnited States
- Department of Clinical SciencesUniversity of Texas Southwestern Medical CenterDallasUnited States
- Department of BioinformaticsUniversity of Texas Southwestern Medical CenterDallasUnited States
| | - Hongtao Yu
- Howard Hughes Medical Institute, Department of PharmacologyUniversity of Texas Southwestern Medical CenterDallasUnited States
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38
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Murayama Y, Samora CP, Kurokawa Y, Iwasaki H, Uhlmann F. Establishment of DNA-DNA Interactions by the Cohesin Ring. Cell 2018; 172:465-477.e15. [PMID: 29358048 PMCID: PMC5786502 DOI: 10.1016/j.cell.2017.12.021] [Citation(s) in RCA: 91] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 10/12/2017] [Accepted: 12/16/2017] [Indexed: 01/14/2023]
Abstract
The ring-shaped structural maintenance of chromosome (SMC) complexes are multi-subunit ATPases that topologically encircle DNA. SMC rings make vital contributions to numerous chromosomal functions, including mitotic chromosome condensation, sister chromatid cohesion, DNA repair, and transcriptional regulation. They are thought to do so by establishing interactions between more than one DNA. Here, we demonstrate DNA-DNA tethering by the purified fission yeast cohesin complex. DNA-bound cohesin efficiently and topologically captures a second DNA, but only if that is single-stranded DNA (ssDNA). Like initial double-stranded DNA (dsDNA) embrace, second ssDNA capture is ATP-dependent, and it strictly requires the cohesin loader complex. Second-ssDNA capture is relatively labile but is converted into stable dsDNA-dsDNA cohesion through DNA synthesis. Our study illustrates second-DNA capture by an SMC complex and provides a molecular model for the establishment of sister chromatid cohesion.
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Affiliation(s)
- Yasuto Murayama
- Institute of Innovative Research, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan.
| | - Catarina P Samora
- Chromosome Segregation Laboratory, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Yumiko Kurokawa
- Education Academy of Computational Life Sciences, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan
| | - Hiroshi Iwasaki
- Institute of Innovative Research, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan
| | - Frank Uhlmann
- Institute of Innovative Research, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan; Chromosome Segregation Laboratory, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
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39
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Murayama Y. DNA entry, exit and second DNA capture by cohesin: insights from biochemical experiments. Nucleus 2018; 9:492-502. [PMID: 30205748 PMCID: PMC6244732 DOI: 10.1080/19491034.2018.1516486] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Revised: 07/28/2018] [Accepted: 08/16/2018] [Indexed: 12/23/2022] Open
Abstract
Cohesin is a ring-shaped, multi-subunit ATPase assembly that is fundamental to the spatiotemporal organization of chromosomes. The ring establishes a variety of chromosomal structures including sister chromatid cohesion and chromatin loops. At the core of the ring is a pair of highly conserved SMC (Structural Maintenance of Chromosomes) proteins, which are closed by the flexible kleisin subunit. In common with other essential SMC complexes including condensin and the SMC5-6 complex, cohesin encircles DNA inside its cavity, with the aid of HEAT (Huntingtin, elongation factor 3, protein phosphatase 2A and TOR) repeat auxiliary proteins. Through this topological embrace, cohesin is thought to establish a series of intra- and interchromosomal interactions by tethering more than one DNA molecule. Recent progress in biochemical reconstitution of cohesin provides molecular insights into how this ring complex topologically binds and mediates DNA-DNA interactions. Here, I review these studies and discuss how cohesin mediates such chromosome interactions.
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Affiliation(s)
- Yasuto Murayama
- Chromosome Biochemistry Laboratory, Center for Frontier Research, National Institute of Genetics, Mishima, Shizuoka, Japan
- Department of Genetics, SOKENDAI (The Graduate University for Advanced Studies), Mishima, Shizuoka, Japan
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40
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Bloom MS, Koshland D, Guacci V. Cohesin Function in Cohesion, Condensation, and DNA Repair Is Regulated by Wpl1p via a Common Mechanism in Saccharomyces cerevisiae. Genetics 2018; 208:111-124. [PMID: 29158426 PMCID: PMC5753852 DOI: 10.1534/genetics.117.300537] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Accepted: 11/16/2017] [Indexed: 11/18/2022] Open
Abstract
Cohesin tethers DNA to mediate sister chromatid cohesion, chromosome condensation, and DNA repair. How the cell regulates cohesin to perform these distinct functions remains to be elucidated. One cohesin regulator, Wpl1p, was characterized in Saccharomyces cerevisiae as a promoter of efficient cohesion and an inhibitor of condensation. Wpl1p is also required for resistance to DNA-damaging agents. Here, we provide evidence that Wpl1p promotes the timely repair of DNA damage induced during S-phase. Previous studies have indicated that Wpl1p destabilizes cohesin's binding to DNA by modulating the interface between the cohesin subunits Mcd1p and Smc3p Our results suggest that Wpl1p likely modulates this interface to regulate all of cohesin's biological functions. Furthermore, we show that Wpl1p regulates cohesion and condensation through the formation of a functional complex with another cohesin-associated factor, Pds5p In contrast, Wpl1p regulates DNA repair independently of its interaction with Pds5p Together, these results suggest that Wpl1p regulates distinct biological functions of cohesin by Pds5p-dependent and -independent modulation of the Smc3p/Mcd1p interface.
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Affiliation(s)
- Michelle S Bloom
- Department of Molecular and Cell Biology, University of California, Berkeley, California 94720
| | - Douglas Koshland
- Department of Molecular and Cell Biology, University of California, Berkeley, California 94720
| | - Vincent Guacci
- Department of Molecular and Cell Biology, University of California, Berkeley, California 94720
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41
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Gassler J, Brandão HB, Imakaev M, Flyamer IM, Ladstätter S, Bickmore WA, Peters JM, Mirny LA, Tachibana K. A mechanism of cohesin-dependent loop extrusion organizes zygotic genome architecture. EMBO J 2017; 36:3600-3618. [PMID: 29217590 PMCID: PMC5730859 DOI: 10.15252/embj.201798083] [Citation(s) in RCA: 243] [Impact Index Per Article: 34.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Revised: 11/06/2017] [Accepted: 11/07/2017] [Indexed: 02/03/2023] Open
Abstract
Fertilization triggers assembly of higher-order chromatin structure from a condensed maternal and a naïve paternal genome to generate a totipotent embryo. Chromatin loops and domains have been detected in mouse zygotes by single-nucleus Hi-C (snHi-C), but not bulk Hi-C. It is therefore unclear when and how embryonic chromatin conformations are assembled. Here, we investigated whether a mechanism of cohesin-dependent loop extrusion generates higher-order chromatin structures within the one-cell embryo. Using snHi-C of mouse knockout embryos, we demonstrate that the zygotic genome folds into loops and domains that critically depend on Scc1-cohesin and that are regulated in size and linear density by Wapl. Remarkably, we discovered distinct effects on maternal and paternal chromatin loop sizes, likely reflecting differences in loop extrusion dynamics and epigenetic reprogramming. Dynamic polymer models of chromosomes reproduce changes in snHi-C, suggesting a mechanism where cohesin locally compacts chromatin by active loop extrusion, whose processivity is controlled by Wapl. Our simulations and experimental data provide evidence that cohesin-dependent loop extrusion organizes mammalian genomes over multiple scales from the one-cell embryo onward.
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Affiliation(s)
- Johanna Gassler
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna Biocenter (VBC), Vienna, Austria
| | - Hugo B Brandão
- Harvard Graduate Program in Biophysics, Harvard University, Cambridge, MA, USA
| | - Maxim Imakaev
- Institute for Medical Engineering and Science, Massachusetts Institute of Technology (MIT), Cambridge, MA, USA
- Department of Physics, Massachusetts Institute of Technology (MIT), Cambridge, MA, USA
| | - Ilya M Flyamer
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, UK
| | - Sabrina Ladstätter
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna Biocenter (VBC), Vienna, Austria
| | - Wendy A Bickmore
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, UK
| | - Jan-Michael Peters
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
| | - Leonid A Mirny
- Harvard Graduate Program in Biophysics, Harvard University, Cambridge, MA, USA
- Institute for Medical Engineering and Science, Massachusetts Institute of Technology (MIT), Cambridge, MA, USA
| | - Kikuë Tachibana
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna Biocenter (VBC), Vienna, Austria
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42
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Shen D, Skibbens RV. Chl1 DNA helicase and Scc2 function in chromosome condensation through cohesin deposition. PLoS One 2017; 12:e0188739. [PMID: 29186203 PMCID: PMC5706694 DOI: 10.1371/journal.pone.0188739] [Citation(s) in RCA: 9] [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: 06/05/2017] [Accepted: 11/13/2017] [Indexed: 02/02/2023] Open
Abstract
Chl1 DNA helicase promotes sister chromatid cohesion and associates with both the cohesion establishment acetyltransferase Eco1/Ctf7 and the DNA polymerase processivity factor PCNA that supports Eco1/Ctf7 function. Mutation in CHL1 results in precocious sister chromatid separation and cell aneuploidy, defects that arise through reduced levels of chromatin-bound cohesins which normally tether together sister chromatids (trans tethering). Mutation of Chl1 family members (BACH1/BRIP/FANCJ and DDX11/ChlR1) also exhibit genotoxic sensitivities, consistent with a role for Chl1 in trans tethering which is required for efficient DNA repair. Chl1 promotes the recruitment of Scc2 to DNA which is required for cohesin deposition onto DNA. There is limited evidence, however, that Scc2 also directs the deposition onto DNA of condensins which promote tethering in cis (intramolecular DNA links). Here, we test the ability of Chl1 to promote cis tethering and the role of both Chl1 and Scc2 to promote condensin recruitment to DNA. The results reveal that chl1 mutant cells exhibit significant condensation defects both within the rDNA locus and genome-wide. Importantly, chl1 mutant cell condensation defects do not result from reduced chromatin binding of condensin, but instead through reduced chromatin binding of cohesin. We tested scc2-4 mutant cells and similarly found no evidence of reduced condensin recruitment to chromatin. Consistent with a role for Scc2 specifically in cohesin deposition, scc2-4 mutant cell condensation defects are irreversible. We thus term Chl1 a novel regulator of both chromatin condensation and sister chromatid cohesion through cohesin-based mechanisms. These results reveal an exciting interface between DNA structure and the highly conserved cohesin complex.
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Affiliation(s)
- Donglai Shen
- Department of Biological Sciences, Lehigh University, Bethlehem, Pennsylvania, United States of America
| | - Robert V. Skibbens
- Department of Biological Sciences, Lehigh University, Bethlehem, Pennsylvania, United States of America
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43
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de Los Santos-Velázquez AI, de Oya IG, Manzano-López J, Monje-Casas F. Late rDNA Condensation Ensures Timely Cdc14 Release and Coordination of Mitotic Exit Signaling with Nucleolar Segregation. Curr Biol 2017; 27:3248-3263.e5. [PMID: 29056450 DOI: 10.1016/j.cub.2017.09.028] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Revised: 08/16/2017] [Accepted: 09/13/2017] [Indexed: 12/28/2022]
Abstract
The nucleolus plays a pivotal role in multiple key cellular processes. An illustrative example is the regulation of mitotic exit in Saccharomyces cerevisiae through the nucleolar sequestration of the Cdc14 phosphatase. The peculiar structure of the nucleolus, however, has also its drawbacks. The repetitive nature of the rDNA gives rise to cohesion-independent linkages whose resolution in budding yeast requires the Cdc14-dependent inhibition of rRNA transcription, which facilitates condensin accessibility to this locus. Thus, the rDNA condenses and segregates later than most other yeast genomic regions. Here, we show that defective function of a small nucleolar ribonucleoprotein particle (snoRNP) assembly factor facilitates condensin accessibility to the rDNA and induces nucleolar hyper-condensation. Interestingly, this increased compaction of the nucleolus interferes with the proper release of Cdc14 from this organelle. This observation provides an explanation for the delayed rDNA condensation in budding yeast, which is necessary to efficiently coordinate timely Cdc14 release and mitotic exit with nucleolar compaction and segregation.
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Affiliation(s)
- Ana Isabel de Los Santos-Velázquez
- Centro Andaluz de Biología Molecular y Medicina Regenerativa (CABIMER), Spanish National Research Council (CSIC), University of Seville, and University Pablo de Olavide, Avda. Américo Vespucio 24, 41092 Sevilla, Spain
| | - Inés G de Oya
- Centro Andaluz de Biología Molecular y Medicina Regenerativa (CABIMER), Spanish National Research Council (CSIC), University of Seville, and University Pablo de Olavide, Avda. Américo Vespucio 24, 41092 Sevilla, Spain
| | - Javier Manzano-López
- Centro Andaluz de Biología Molecular y Medicina Regenerativa (CABIMER), Spanish National Research Council (CSIC), University of Seville, and University Pablo de Olavide, Avda. Américo Vespucio 24, 41092 Sevilla, Spain
| | - Fernando Monje-Casas
- Centro Andaluz de Biología Molecular y Medicina Regenerativa (CABIMER), Spanish National Research Council (CSIC), University of Seville, and University Pablo de Olavide, Avda. Américo Vespucio 24, 41092 Sevilla, Spain.
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44
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Increased LOH due to Defective Sister Chromatid Cohesion Is due Primarily to Chromosomal Aneuploidy and not Recombination. G3-GENES GENOMES GENETICS 2017; 7:3305-3315. [PMID: 28983067 PMCID: PMC5633381 DOI: 10.1534/g3.117.300091] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Loss of heterozygosity (LOH) is an important factor in cancer, pathogenic fungi, and adaptation to changing environments. The sister chromatid cohesion process (SCC) suppresses aneuploidy and therefore whole chromosome LOH. SCC is also important to channel recombinational repair to sister chromatids, thereby preventing LOH mediated by allelic recombination. There is, however, insufficient information about the relative roles that the SCC pathway plays in the different modes of LOH. Here, we found that the cohesin mutation mcd1-1, and other mutations in SCC, differentially affect the various types of LOH. The greatest effect, by three orders of magnitude, was on whole chromosome loss (CL). In contrast, there was little increase in recombination-mediated LOH, even for telomeric markers. Some of the LOH events that were increased by SCC mutations were complex, i.e., they were the result of several chromosome transactions. Although these events were independent of POL32, the most parsimonious way to explain the formation of at least some of them was break-induced replication through the centromere. Interestingly, the mcd1-1 pol32Δ double mutant showed a significant reduction in the rate of CL in comparison with the mcd1-1 single mutant. Our results show that defects in SCC allow the formation of complex LOH events that, in turn, can promote drug or pesticide resistance in diploid microbes that are pathogenic to humans or plants.
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45
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Kinetochore Function from the Bottom Up. Trends Cell Biol 2017; 28:22-33. [PMID: 28985987 DOI: 10.1016/j.tcb.2017.09.002] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2017] [Revised: 09/06/2017] [Accepted: 09/07/2017] [Indexed: 02/06/2023]
Abstract
During a single human lifetime, nearly one quintillion chromosomes separate from their sisters and transit to their destinations in daughter cells. Unlike DNA replication, chromosome segregation has no template, and, unlike transcription, errors frequently lead to a total loss of cell viability. Rapid progress in recent years has shown how kinetochores enable faithful execution of this process by connecting chromosomal DNA to microtubules. These findings have transformed our idea of kinetochores from cytological features to immense molecular machines and now allow molecular interpretation of many long-appreciated kinetochore functions. In this review we trace kinetochore protein connectivity from chromosomal DNA to microtubules, relating new findings to important points of regulation and function.
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46
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Hinshaw SM, Makrantoni V, Harrison SC, Marston AL. The Kinetochore Receptor for the Cohesin Loading Complex. Cell 2017; 171:72-84.e13. [PMID: 28938124 PMCID: PMC5610175 DOI: 10.1016/j.cell.2017.08.017] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2017] [Revised: 05/03/2017] [Accepted: 08/09/2017] [Indexed: 12/29/2022]
Abstract
The ring-shaped cohesin complex brings together distant DNA domains to maintain, express, and segregate the genome. Establishing specific chromosomal linkages depends on cohesin recruitment to defined loci. One such locus is the budding yeast centromere, which is a paradigm for targeted cohesin loading. The kinetochore, a multiprotein complex that connects centromeres to microtubules, drives the recruitment of high levels of cohesin to link sister chromatids together. We have exploited this system to determine the mechanism of specific cohesin recruitment. We show that phosphorylation of the Ctf19 kinetochore protein by a conserved kinase, DDK, provides a binding site for the Scc2/4 cohesin loading complex, thereby directing cohesin loading to centromeres. A similar mechanism targets cohesin to chromosomes in vertebrates. These findings represent a complete molecular description of targeted cohesin loading, a phenomenon with wide-ranging importance in chromosome segregation and, in multicellular organisms, transcription regulation.
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Affiliation(s)
- Stephen M Hinshaw
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
| | - Vasso Makrantoni
- The Wellcome Trust Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Stephen C Harrison
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Howard Hughes Medical Institute, Chevy Chase, MD, USA.
| | - Adèle L Marston
- The Wellcome Trust Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK.
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47
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Schalbetter SA, Goloborodko A, Fudenberg G, Belton JM, Miles C, Yu M, Dekker J, Mirny L, Baxter J. SMC complexes differentially compact mitotic chromosomes according to genomic context. Nat Cell Biol 2017; 19:1071-1080. [PMID: 28825700 PMCID: PMC5640152 DOI: 10.1038/ncb3594] [Citation(s) in RCA: 86] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Accepted: 07/19/2017] [Indexed: 12/26/2022]
Abstract
Structural maintenance of chromosomes (SMC) protein complexes are key determinants of chromosome conformation. Using Hi-C and polymer modelling, we study how cohesin and condensin, two deeply conserved SMC complexes, organize chromosomes in the budding yeast Saccharomyces cerevisiae. The canonical role of cohesin is to co-align sister chromatids, while condensin generally compacts mitotic chromosomes. We find strikingly different roles for the two complexes in budding yeast mitosis. First, cohesin is responsible for compacting mitotic chromosome arms, independently of sister chromatid cohesion. Polymer simulations demonstrate that this role can be fully accounted for through cis-looping of chromatin. Second, condensin is generally dispensable for compaction along chromosome arms. Instead, it plays a targeted role compacting the rDNA proximal regions and promoting resolution of peri-centromeric regions. Our results argue that the conserved mechanism of SMC complexes is to form chromatin loops and that distinct SMC-dependent looping activities are selectively deployed to appropriately compact chromosomes.
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MESH Headings
- Adenosine Triphosphatases/genetics
- Adenosine Triphosphatases/metabolism
- Cell Cycle Proteins/genetics
- Cell Cycle Proteins/metabolism
- Chromatin/chemistry
- Chromatin/genetics
- Chromatin/metabolism
- Chromatin Assembly and Disassembly
- Chromosomal Proteins, Non-Histone/genetics
- Chromosomal Proteins, Non-Histone/metabolism
- Chromosome Structures
- Chromosomes, Fungal/chemistry
- Chromosomes, Fungal/genetics
- Chromosomes, Fungal/metabolism
- Computer Simulation
- DNA, Fungal/chemistry
- DNA, Fungal/genetics
- DNA, Fungal/metabolism
- DNA, Ribosomal/chemistry
- DNA, Ribosomal/genetics
- DNA, Ribosomal/metabolism
- DNA-Binding Proteins/genetics
- DNA-Binding Proteins/metabolism
- Mitosis
- Models, Genetic
- Models, Molecular
- Multiprotein Complexes/genetics
- Multiprotein Complexes/metabolism
- Nucleic Acid Conformation
- Saccharomyces cerevisiae/genetics
- Saccharomyces cerevisiae/growth & development
- Saccharomyces cerevisiae/metabolism
- Saccharomyces cerevisiae Proteins/genetics
- Saccharomyces cerevisiae Proteins/metabolism
- Structure-Activity Relationship
- Cohesins
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Affiliation(s)
| | - Anton Goloborodko
- Institute for Medical Engineering and Sciences, Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Geoffrey Fudenberg
- Institute for Medical Engineering and Sciences, Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Jon-Matthew Belton
- Program in Systems Biology, University of Massachusetts Medical School, Worcester, Massachusetts 01605, USA
| | - Catrina Miles
- Genome Damage and Stability Centre, Science Park Road, University of Sussex, Falmer, Brighton BN1 9RQ, UK
| | - Miao Yu
- Genome Damage and Stability Centre, Science Park Road, University of Sussex, Falmer, Brighton BN1 9RQ, UK
| | - Job Dekker
- Program in Systems Biology, University of Massachusetts Medical School, Worcester, Massachusetts 01605, USA
| | - Leonid Mirny
- Institute for Medical Engineering and Sciences, Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Jonathan Baxter
- Genome Damage and Stability Centre, Science Park Road, University of Sussex, Falmer, Brighton BN1 9RQ, UK
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48
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Schalch T, Steiner FA. Structure of centromere chromatin: from nucleosome to chromosomal architecture. Chromosoma 2017; 126:443-455. [PMID: 27858158 PMCID: PMC5509776 DOI: 10.1007/s00412-016-0620-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 11/09/2016] [Accepted: 11/10/2016] [Indexed: 12/14/2022]
Abstract
The centromere is essential for the segregation of chromosomes, as it serves as attachment site for microtubules to mediate chromosome segregation during mitosis and meiosis. In most organisms, the centromere is restricted to one chromosomal region that appears as primary constriction on the condensed chromosome and is partitioned into two chromatin domains: The centromere core is characterized by the centromere-specific histone H3 variant CENP-A (also called cenH3) and is required for specifying the centromere and for building the kinetochore complex during mitosis. This core region is generally flanked by pericentric heterochromatin, characterized by nucleosomes containing H3 methylated on lysine 9 (H3K9me) that are bound by heterochromatin proteins. During mitosis, these two domains together form a three-dimensional structure that exposes CENP-A-containing chromatin to the surface for interaction with the kinetochore and microtubules. At the same time, this structure supports the tension generated during the segregation of sister chromatids to opposite poles. In this review, we discuss recent insight into the characteristics of the centromere, from the specialized chromatin structures at the centromere core and the pericentromere to the three-dimensional organization of these regions that make up the functional centromere.
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Affiliation(s)
- Thomas Schalch
- Department of Molecular Biology, Sciences III, Institute of Genetics and Genomics of Geneva (iGE3), University of Geneva, Geneva, Switzerland.
| | - Florian A Steiner
- Department of Molecular Biology, Sciences III, Institute of Genetics and Genomics of Geneva (iGE3), University of Geneva, Geneva, Switzerland.
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49
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Abstract
Chromatin condensation during mitosis produces detangled and discrete DNA entities required for high fidelity sister chromatid segregation during mitosis and positions DNA away from the cleavage furrow during cytokinesis. Regional condensation during G1 also establishes a nuclear architecture through which gene transcription is regulated but remains plastic so that cells can respond to changes in nutrient levels, temperature and signaling molecules. To date, however, the potential impact of this plasticity on mitotic chromosome condensation remains unknown. Here, we report results obtained from a new condensation assay that wildtype budding yeast cells exhibit dramatic changes in rDNA conformation in response to temperature. rDNA hypercondenses in wildtype cells maintained at 37°C, compared with cells maintained at 23°C. This hypercondensation machinery can be activated during preanaphase but readily inactivated upon exposure to lower temperatures. Extended mitotic arrest at 23°C does not result in hypercondensation, negating a kinetic-based argument in which condensation that typically proceeds slowly is accelerated when cells are placed at 37°C. Neither elevated recombination nor reduced transcription appear to promote this hypercondensation. This heretofore undetected temperature-dependent hypercondensation pathway impacts current views of chromatin structure based on conditional mutant gene analyses and significantly extends our understanding of physiologic changes in chromatin architecture in response to hypothermia.
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Affiliation(s)
- Donglai Shen
- a Department of Biological Sciences , Lehigh University , Bethlehem , PA , USA
| | - Robert V Skibbens
- a Department of Biological Sciences , Lehigh University , Bethlehem , PA , USA
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50
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Abstract
The kollerin complex, consisting of Scc2/Scc4 in yeast and Nipbl/Mau2 in vertebrates, is crucial for the chromatin-association of the cohesin complex and therefore for the critical functions of cohesin in cell division, transcriptional regulation and chromatin organisation. Despite the recent efforts to determine the genomic localization of the kollerin complex in different cell lines, major questions still remain unresolved, for instance where cohesin is actually loaded onto chromatin. Further, Nipbl seems to have also additional roles, for instance as transcription factor.This chapter summarizes our current knowledge on kollerin function and the recent studies on the genomic localization of Scc2, highlighting and critically discussing controversial data.
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Affiliation(s)
- Kerstin S Wendt
- Department of Cell Biology, Erasmus MC, Faculty Building, Room Ee1020, Wytemaweg 80, 3015 CN, Rotterdam, The Netherlands.
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