1
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García-Ruano D, Hsu I, Leray B, Billard B, Liti G, Coudreuse D. Engineering heterothallic strains in fission yeast. Yeast 2024; 41:87-94. [PMID: 38099423 DOI: 10.1002/yea.3914] [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: 09/13/2023] [Revised: 10/18/2023] [Accepted: 11/15/2023] [Indexed: 02/24/2024] Open
Abstract
In poor nitrogen conditions, fission yeast cells mate, undergo meiosis and form spores that are resistant to deleterious environments. Natural isolates of Schizosaccharomyces pombe are homothallic. This allows them to naturally switch between the two h- and h+ mating types with a high frequency, thereby ensuring the presence of both mating partners in a population of cells. However, alteration of the mating type locus can abolish mating type switching or reduce it to a very low frequency. Such heterothallic strains have been isolated and are common in research laboratories due to the simplicity of their use for Mendelian genetics. In addition to the standard laboratory strains, a large collection of natural S. pombe isolates is now available, representing a powerful resource for investigating the genetic diversity and biology of fission yeast. However, most of these strains are homothallic, and only tedious or mutagenic strategies have been described to obtain heterothallic cells from a homothallic parent. Here, we describe a simple approach to generate heterothallic strains. It takes advantage of an alteration of the mating type locus that was previously identified in a mating type switching-deficient strain and the CRISPR-Cas9 editing tool, allowing for a one-step engineering of heterothallic cells with high efficiency.
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Affiliation(s)
- Daniel García-Ruano
- Institute of Biochemistry and Cellular Genetics, CNRS UMR 5095, University of Bordeaux, Bordeaux, France
| | - Ian Hsu
- Université Côte d'Azur, CNRS, INSERM, IRCAN, Nice, France
| | - Baptiste Leray
- Institute of Biochemistry and Cellular Genetics, CNRS UMR 5095, University of Bordeaux, Bordeaux, France
| | | | - Gianni Liti
- Université Côte d'Azur, CNRS, INSERM, IRCAN, Nice, France
| | - Damien Coudreuse
- Institute of Biochemistry and Cellular Genetics, CNRS UMR 5095, University of Bordeaux, Bordeaux, France
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2
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Tian Y, Liu L, Gao J, Wang R. Homologous chromosome pairing: The linchpin of accurate segregation in meiosis. J Cell Physiol 2024; 239:3-19. [PMID: 38032002 DOI: 10.1002/jcp.31166] [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: 09/09/2023] [Revised: 11/13/2023] [Accepted: 11/20/2023] [Indexed: 12/01/2023]
Abstract
Meiosis is a specialized cell division that occurs in sexually reproducing organisms, generating haploid gametes containing half the chromosome number through two rounds of cell division. Homologous chromosomes pair and prepare for their proper segregation in subsequent divisions. How homologous chromosomes recognize each other and achieve pairing is an important question. Early studies showed that in most organisms, homologous pairing relies on homologous recombination. However, pairing mechanisms differ across species. Evidence indicates that chromosomes are dynamic and move during early meiotic stages, facilitating pairing. Recent studies in various model organisms suggest conserved mechanisms and key regulators of homologous chromosome pairing. This review summarizes these findings and compare similarities and differences in homologous chromosome pairing mechanisms across species.
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Affiliation(s)
- Yuqi Tian
- Center for Cell Structure and Function, College of Life Sciences, Key Laboratory of Animal Resistance Biology of Shandong Province, Shandong Normal University, Jinan, China
| | - Libo Liu
- Center for Cell Structure and Function, College of Life Sciences, Key Laboratory of Animal Resistance Biology of Shandong Province, Shandong Normal University, Jinan, China
| | - Jinmin Gao
- Center for Cell Structure and Function, College of Life Sciences, Key Laboratory of Animal Resistance Biology of Shandong Province, Shandong Normal University, Jinan, China
| | - Ruoxi Wang
- Center for Cell Structure and Function, College of Life Sciences, Key Laboratory of Animal Resistance Biology of Shandong Province, Shandong Normal University, Jinan, China
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3
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Solé M, Pascual Á, Anton E, Blanco J, Sarrate Z. The courtship choreography of homologous chromosomes: timing and mechanisms of DSB-independent pairing. Front Cell Dev Biol 2023; 11:1191156. [PMID: 37377734 PMCID: PMC10291267 DOI: 10.3389/fcell.2023.1191156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Accepted: 06/01/2023] [Indexed: 06/29/2023] Open
Abstract
Meiosis involves deep changes in the spatial organisation and interactions of chromosomes enabling the two primary functions of this process: increasing genetic diversity and reducing ploidy level. These two functions are ensured by crucial events such as homologous chromosomal pairing, synapsis, recombination and segregation. In most sexually reproducing eukaryotes, homologous chromosome pairing depends on a set of mechanisms, some of them associated with the repair of DNA double-strand breaks (DSBs) induced at the onset of prophase I, and others that operate before DSBs formation. In this article, we will review various strategies utilised by model organisms for DSB-independent pairing. Specifically, we will focus on mechanisms such as chromosome clustering, nuclear and chromosome movements, as well as the involvement of specific proteins, non-coding RNA, and DNA sequences.
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Affiliation(s)
| | | | | | - Joan Blanco
- *Correspondence: Joan Blanco, ; Zaida Sarrate,
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4
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Pollard MG, Rockmill B, Oke A, Anderson CM, Fung JC. Kinetic analysis of synaptonemal complex dynamics during meiosis of yeast Saccharomyces cerevisiae reveals biphasic growth and abortive disassembly. Front Cell Dev Biol 2023; 11:1098468. [PMID: 36814598 PMCID: PMC9939684 DOI: 10.3389/fcell.2023.1098468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 01/19/2023] [Indexed: 02/08/2023] Open
Abstract
The synaptonemal complex (SC) is a dynamic structure formed between chromosomes during meiosis which stabilizes and supports many essential meiotic processes such as pairing and recombination. In budding yeast, Zip1 is a functionally conserved element of the SC that is important for synapsis. Here, we directly measure the kinetics of Zip1-GFP assembly and disassembly in live cells of the yeast S. cerevisiae. The imaging of SC assembly in yeast is challenging due to the large number of chromosomes packed into a small nucleus. We employ a zip3Δ mutant in which only a few chromosomes undergo synapsis at any given time, initiating from a single site on each chromosome, thus allowing the assembly and disassembly kinetics of single SCs to be accurately monitored in living cells. SC assembly occurs with both monophasic and biphasic kinetics, in contrast to the strictly monophasic assembly seen in C. elegans. In wild-type cells, once maximal synapsis is achieved, programmed final disassembly rapidly follows, as Zip1 protein is actively degraded. In zip3Δ, this period is extended and final disassembly is prolonged. Besides final disassembly, we found novel disassembly events involving mostly short SCs that disappeared in advance of programmed final disassembly, which we termed "abortive disassembly." Abortive disassembly is distinct from final disassembly in that it occurs when Zip1 protein levels are still high, and exhibits a much slower rate of disassembly, suggesting a different mechanism for removal in the two types of disassembly. We speculate that abortive disassembly events represent defective or stalled SCs, possibly representing SC formation between non-homologs, that is then targeted for dissolution. These results reveal novel aspects of SC assembly and disassembly, potentially providing evidence of additional regulatory pathways controlling not just the assembly, but also the disassembly, of this complex cellular structure.
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Affiliation(s)
| | | | | | | | - Jennifer C. Fung
- Department of Obstetrics, Gynecology and Reproductive Sciences, Center of Reproductive Sciences, University of California, San Francisco, San Francisco, CA, United States
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5
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Sakuno T, Tashiro S, Tanizawa H, Iwasaki O, Ding DQ, Haraguchi T, Noma KI, Hiraoka Y. Rec8 Cohesin-mediated Axis-loop chromatin architecture is required for meiotic recombination. Nucleic Acids Res 2022; 50:3799-3816. [PMID: 35333350 PMCID: PMC9023276 DOI: 10.1093/nar/gkac183] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 03/08/2022] [Accepted: 03/09/2022] [Indexed: 11/13/2022] Open
Abstract
During meiotic prophase, cohesin-dependent axial structures are formed in the synaptonemal complex (SC). However, the functional correlation between these structures and cohesion remains elusive. Here, we examined the formation of cohesin-dependent axial structures in the fission yeast Schizosaccharomyces pombe. This organism forms atypical SCs composed of linear elements (LinEs) resembling the lateral elements of SC but lacking the transverse filaments. Hi-C analysis using a highly synchronous population of meiotic S. pombe cells revealed that the axis-loop chromatin structure formed in meiotic prophase was dependent on the Rec8 cohesin complex. In contrast, the Rec8-mediated formation of the axis-loop structure occurred in cells lacking components of LinEs. To dissect the functions of Rec8, we identified a rec8-F204S mutant that lost the ability to assemble the axis-loop structure without losing cohesion of sister chromatids. This mutant showed defects in the formation of the axis-loop structure and LinE assembly and thus exhibited reduced meiotic recombination. Collectively, our results demonstrate that the Rec8-dependent axis-loop structure provides a structural platform essential for LinE assembly, facilitating meiotic recombination of homologous chromosomes, independently of its role in sister chromatid cohesion.
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Affiliation(s)
- Takeshi Sakuno
- Graduate School of Frontier Biosciences, Osaka University, Suita 565-0871, Japan
| | - Sanki Tashiro
- Institute of Molecular Biology, University of Oregon, Eugene, OR 97403, USA
| | - Hideki Tanizawa
- Institute of Molecular Biology, University of Oregon, Eugene, OR 97403, USA
| | - Osamu Iwasaki
- Institute of Molecular Biology, University of Oregon, Eugene, OR 97403, USA
| | - Da-Qiao Ding
- Advanced ICT Research Institute Kobe, National Institute of Information and Communications Technology, Kobe 651-2492, Japan
| | - Tokuko Haraguchi
- Graduate School of Frontier Biosciences, Osaka University, Suita 565-0871, Japan
| | - Ken-ichi Noma
- Institute of Molecular Biology, University of Oregon, Eugene, OR 97403, USA
- Institute for Genetic Medicine, Hokkaido University, Sapporo 060-0815, Japan
| | - Yasushi Hiraoka
- Graduate School of Frontier Biosciences, Osaka University, Suita 565-0871, Japan
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6
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Chuang YC, Smith GR. Dynamic configurations of meiotic DNA-break hotspot determinant proteins. J Cell Sci 2022; 135:274269. [PMID: 35028663 PMCID: PMC8918816 DOI: 10.1242/jcs.259061] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 12/29/2021] [Indexed: 11/20/2022] Open
Abstract
Appropriate DNA double-strand break (DSB) and crossover distributions are required for proper meiotic chromosome segregation. Schizosaccharomyces pombe linear element proteins (LinEs) determine DSB hotspots; LinE-bound hotspots form three-dimensional clusters over ∼200 kb chromosomal regions. Here, we investigated LinE configurations and distributions in live cells using super-resolution fluorescence microscopy. We found LinEs form two chromosomal structures, dot-like and linear structures, in both zygotic and azygotic meiosis. Dot-like LinE structures appeared around the time of meiotic DNA replication, underwent dotty-to-linear-to-dotty configurational transitions and disassembled before the first meiotic division. DSB formation and repair did not detectably influence LinE structure formation but failure of DSB formation delayed disassembly. Recombination-deficient LinE missense mutants formed dot-like, but not linear, LinE structures. Our quantitative study reveals a transient form of LinE structures and suggests a novel role for LinE proteins in regulating meiotic events, such as DSB repair. We discuss the relationship of LinEs and the synaptonemal complex in other species. This article has an associated First Person interview with the first author of the paper.
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7
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Hyppa RW, Cho JD, Nambiar M, Smith GR. Redirecting meiotic DNA break hotspot determinant proteins alters localized spatial control of DNA break formation and repair. Nucleic Acids Res 2022; 50:899-914. [PMID: 34967417 PMCID: PMC8789058 DOI: 10.1093/nar/gkab1253] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 12/02/2021] [Accepted: 12/28/2021] [Indexed: 01/21/2023] Open
Abstract
During meiosis, DNA double-strand breaks (DSBs) are formed at high frequency at special chromosomal sites, called DSB hotspots, to generate crossovers that aid proper chromosome segregation. Multiple chromosomal features affect hotspot formation. In the fission yeast S. pombe the linear element proteins Rec25, Rec27 and Mug20 are hotspot determinants - they bind hotspots with high specificity and are necessary for nearly all DSBs at hotspots. To assess whether they are also sufficient for hotspot determination, we localized each linear element protein to a novel chromosomal site (ade6 with lacO substitutions) by fusion to the Escherichia coli LacI repressor. The Mug20-LacI plus lacO combination, but not the two separate lac elements, produced a strong ade6 DSB hotspot, comparable to strong endogenous DSB hotspots. This hotspot had unexpectedly low ade6 recombinant frequency and negligible DSB hotspot competition, although like endogenous hotspots it manifested DSB interference. We infer that linear element proteins must be properly placed by endogenous functions to impose hotspot competition and proper partner choice for DSB repair. Our results support and expand our previously proposed DSB hotspot-clustering model for local control of meiotic recombination.
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Affiliation(s)
- Randy W Hyppa
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Joshua D Cho
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Mridula Nambiar
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Gerald R Smith
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
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8
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Sakuno T, Hiraoka Y. Rec8 Cohesin: A Structural Platform for Shaping the Meiotic Chromosomes. Genes (Basel) 2022; 13:200. [PMID: 35205245 PMCID: PMC8871791 DOI: 10.3390/genes13020200] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 01/17/2022] [Accepted: 01/21/2022] [Indexed: 11/17/2022] Open
Abstract
Meiosis is critically different from mitosis in that during meiosis, pairing and segregation of homologous chromosomes occur. During meiosis, the morphology of sister chromatids changes drastically, forming a prominent axial structure in the synaptonemal complex. The meiosis-specific cohesin complex plays a central role in the regulation of the processes required for recombination. In particular, the Rec8 subunit of the meiotic cohesin complex, which is conserved in a wide range of eukaryotes, has been analyzed for its function in modulating chromosomal architecture during the pairing and recombination of homologous chromosomes in meiosis. Here, we review the current understanding of Rec8 cohesin as a structural platform for meiotic chromosomes.
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Affiliation(s)
| | - Yasushi Hiraoka
- Graduate School of Frontier Biosciences, Osaka University, Suita 565-0871, Japan;
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9
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Pazhayam NM, Turcotte CA, Sekelsky J. Meiotic Crossover Patterning. Front Cell Dev Biol 2021; 9:681123. [PMID: 34368131 PMCID: PMC8344875 DOI: 10.3389/fcell.2021.681123] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 06/28/2021] [Indexed: 12/02/2022] Open
Abstract
Proper number and placement of meiotic crossovers is vital to chromosome segregation, with failures in normal crossover distribution often resulting in aneuploidy and infertility. Meiotic crossovers are formed via homologous repair of programmed double-strand breaks (DSBs). Although DSBs occur throughout the genome, crossover placement is intricately patterned, as observed first in early genetic studies by Muller and Sturtevant. Three types of patterning events have been identified. Interference, first described by Sturtevant in 1915, is a phenomenon in which crossovers on the same chromosome do not occur near one another. Assurance, initially identified by Owen in 1949, describes the phenomenon in which a minimum of one crossover is formed per chromosome pair. Suppression, first observed by Beadle in 1932, dictates that crossovers do not occur in regions surrounding the centromere and telomeres. The mechanisms behind crossover patterning remain largely unknown, and key players appear to act at all scales, from the DNA level to inter-chromosome interactions. There is also considerable overlap between the known players that drive each patterning phenomenon. In this review we discuss the history of studies of crossover patterning, developments in methods used in the field, and our current understanding of the interplay between patterning phenomena.
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Affiliation(s)
- Nila M. Pazhayam
- Curriculum in Genetics and Molecular Biology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Carolyn A. Turcotte
- Curriculum in Genetics and Molecular Biology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Jeff Sekelsky
- Curriculum in Genetics and Molecular Biology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
- Department of Biology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
- Integrative Program for Biological and Genome Sciences, The University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
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10
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Ding DQ, Matsuda A, Okamasa K, Hiraoka Y. Linear elements are stable structures along the chromosome axis in fission yeast meiosis. Chromosoma 2021; 130:149-162. [PMID: 33825974 PMCID: PMC8426239 DOI: 10.1007/s00412-021-00757-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 03/09/2021] [Accepted: 03/10/2021] [Indexed: 11/22/2022]
Abstract
The structure of chromosomes dramatically changes upon entering meiosis to ensure the successful progression of meiosis-specific events. During this process, a multilayer proteinaceous structure called a synaptonemal complex (SC) is formed in many eukaryotes. However, in the fission yeast Schizosaccharomyces pombe, linear elements (LinEs), which are structures related to axial elements of the SC, form on the meiotic cohesin-based chromosome axis. The structure of LinEs has been observed using silver-stained electron micrographs or in immunofluorescence-stained spread nuclei. However, the fine structure of LinEs and their dynamics in intact living cells remain to be elucidated. In this study, we performed live cell imaging with wide-field fluorescence microscopy as well as 3D structured illumination microscopy (3D-SIM) of the core components of LinEs (Rec10, Rec25, Rec27, Mug20) and a linE-binding protein Hop1. We found that LinEs form along the chromosome axis and elongate during meiotic prophase. 3D-SIM microscopy revealed that Rec10 localized to meiotic chromosomes in the absence of other LinE proteins, but shaped into LinEs only in the presence of all three other components, the Rec25, Rec27, and Mug20. Elongation of LinEs was impaired in double-strand break-defective rec12− cells. The structure of LinEs persisted after treatment with 1,6-hexanediol and showed slow fluorescence recovery from photobleaching. These results indicate that LinEs are stable structures resembling axial elements of the SC.
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Affiliation(s)
- Da-Qiao Ding
- Advanced ICT Research Institute Kobe, National Institute of Information and Communications Technology, 588-2 Iwaoka, Iwaoka-cho, Nishi-ku, Kobe, 651-2492, Japan.
| | - Atsushi Matsuda
- Advanced ICT Research Institute Kobe, National Institute of Information and Communications Technology, 588-2 Iwaoka, Iwaoka-cho, Nishi-ku, Kobe, 651-2492, Japan
| | - Kasumi Okamasa
- Advanced ICT Research Institute Kobe, National Institute of Information and Communications Technology, 588-2 Iwaoka, Iwaoka-cho, Nishi-ku, Kobe, 651-2492, Japan
| | - Yasushi Hiraoka
- Graduate School of Frontier Biosciences, Osaka University, Suita, 565-0871, Japan
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11
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Escorcia W, Tripathi VP, Yuan JP, Forsburg SL. A visual atlas of meiotic protein dynamics in living fission yeast. Open Biol 2021; 11:200357. [PMID: 33622106 PMCID: PMC8061692 DOI: 10.1098/rsob.200357] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Meiosis is a carefully choreographed dynamic process that re-purposes proteins from somatic/vegetative cell division, as well as meiosis-specific factors, to carry out the differentiation and recombination pathway common to sexually reproducing eukaryotes. Studies of individual proteins from a variety of different experimental protocols can make it difficult to compare details between them. Using a consistent protocol in otherwise wild-type fission yeast cells, this report provides an atlas of dynamic protein behaviour of representative proteins at different stages during normal zygotic meiosis in fission yeast. This establishes common landmarks to facilitate comparison of different proteins and shows that initiation of S phase likely occurs prior to nuclear fusion/karyogamy.
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Affiliation(s)
- Wilber Escorcia
- Molecular and Computational Biology Program, University of Southern California, Los Angeles, CA 90089, USA.,Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA 45207, USA
| | - Vishnu P Tripathi
- Molecular and Computational Biology Program, University of Southern California, Los Angeles, CA 90089, USA
| | - Ji-Ping Yuan
- Molecular and Computational Biology Program, University of Southern California, Los Angeles, CA 90089, USA
| | - Susan L Forsburg
- Molecular and Computational Biology Program, University of Southern California, Los Angeles, CA 90089, USA
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12
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Wintrebert M, Nguyen MC, Smith GR. Activation of meiotic recombination by nuclear import of the DNA break hotspot-determining complex in fission yeast. J Cell Sci 2021; 134:jcs253518. [PMID: 33526714 PMCID: PMC7929924 DOI: 10.1242/jcs.253518] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Accepted: 01/11/2021] [Indexed: 11/20/2022] Open
Abstract
Meiotic recombination forms crossovers important for proper chromosome segregation and offspring viability. This complex process involves many proteins acting at each of the multiple steps of recombination. Recombination initiates by formation of DNA double-strand breaks (DSBs), which in the several species examined occur with high frequency at special sites (DSB hotspots). In Schizosaccharomyces pombe, DSB hotspots are bound with high specificity and strongly activated by linear element (LinE) proteins Rec25, Rec27 and Mug20, which form colocalized nuclear foci with Rec10, essential for all DSB formation and recombination. Here, we test the hypothesis that the nuclear localization signal (NLS) of Rec10 is crucial for coordinated nuclear entry after forming a complex with other LinE proteins. In NLS mutants, all LinE proteins were abundant in the cytoplasm, not the nucleus; DSB formation and recombination were much reduced but not eliminated. Nuclear entry of limited amounts of Rec10, apparently small enough for passive nuclear entry, can account for residual recombination. LinE proteins are related to synaptonemal complex proteins of other species, suggesting that they also share an NLS, not yet identified, and undergo protein complex formation before nuclear entry.This article has an associated First Person interview with Mélody Wintrebert, joint first author of the paper.
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Affiliation(s)
- Mélody Wintrebert
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Mai-Chi Nguyen
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Gerald R Smith
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
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13
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CDK Regulation of Meiosis: Lessons from S. cerevisiae and S. pombe. Genes (Basel) 2020; 11:genes11070723. [PMID: 32610611 PMCID: PMC7397238 DOI: 10.3390/genes11070723] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2020] [Revised: 06/26/2020] [Accepted: 06/26/2020] [Indexed: 12/13/2022] Open
Abstract
Meiotic progression requires precise orchestration, such that one round of DNA replication is followed by two meiotic divisions. The order and timing of meiotic events is controlled through the modulation of the phosphorylation state of proteins. Key components of this phospho-regulatory system include cyclin-dependent kinase (CDK) and its cyclin regulatory subunits. Over the past two decades, studies in budding and fission yeast have greatly informed our understanding of the role of CDK in meiotic regulation. In this review, we provide an overview of how CDK controls meiotic events in both budding and fission yeast. We discuss mechanisms of CDK regulation through post-translational modifications and changes in the levels of cyclins. Finally, we highlight the similarities and differences in CDK regulation between the two yeast species. Since CDK and many meiotic regulators are highly conserved, the findings in budding and fission yeasts have revealed conserved mechanisms of meiotic regulation among eukaryotes.
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14
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Brown SD, Audoynaud C, Lorenz A. Intragenic meiotic recombination in Schizosaccharomyces pombe is sensitive to environmental temperature changes. Chromosome Res 2020; 28:195-207. [PMID: 32303869 PMCID: PMC7242256 DOI: 10.1007/s10577-020-09632-3] [Citation(s) in RCA: 8] [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: 12/05/2019] [Revised: 03/30/2020] [Accepted: 04/01/2020] [Indexed: 11/25/2022]
Abstract
Changes in environmental temperature influence cellular processes and their dynamics, and thus affect the life cycle of organisms that are unable to control their cell/body temperature. Meiotic recombination is the cellular process essential for producing healthy haploid gametes by providing physical links (chiasmata) between homologous chromosomes to guide their accurate segregation. Additionally, meiotic recombination—initiated by programmed DNA double-strand breaks (DSBs)—can generate genetic diversity and, therefore, is a driving force of evolution. Environmental temperature influencing meiotic recombination outcome thus may be a crucial determinant of reproductive success and genetic diversity. Indeed, meiotic recombination frequency in fungi, plants and invertebrates changes with temperature. In most organisms, these temperature-induced changes in meiotic recombination seem to be mediated through the meiosis-specific chromosome axis organization, the synaptonemal complex in particular. The fission yeast Schizosaccharomyces pombe does not possess a synaptonemal complex. Thus, we tested how environmental temperature modulates meiotic recombination frequency in the absence of a fully-fledged synaptonemal complex. We show that intragenic recombination (gene conversion) positively correlates with temperature within a certain range, especially at meiotic recombination hotspots. In contrast, crossover recombination, which manifests itself as chiasmata, is less affected. Based on our observations, we suggest that, in addition to changes in DSB frequency, DSB processing could be another temperature-sensitive step causing temperature-induced recombination rate alterations.
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Affiliation(s)
- Simon D Brown
- The Institute of Medical Sciences (IMS), University of Aberdeen, Foresterhill, Aberdeen, AB25 2ZD, UK
- MRC Institute of Genetics & Molecular Medicine, University of Edinburgh, Edinburgh, EH4 2XU, UK
| | - Charlotte Audoynaud
- The Institute of Medical Sciences (IMS), University of Aberdeen, Foresterhill, Aberdeen, AB25 2ZD, UK
- Institut Curie, PSL Research University, UMR3348-CNRS, 91405, Orsay, France
| | - Alexander Lorenz
- The Institute of Medical Sciences (IMS), University of Aberdeen, Foresterhill, Aberdeen, AB25 2ZD, UK.
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15
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Hylton CA, Hansen K, Bourgeois A, Tomkiel Dean JE. Sex Chromosome Pairing Mediated by Euchromatic Homology in Drosophila Male Meiosis. Genetics 2020; 214:605-616. [PMID: 31915134 PMCID: PMC7054017 DOI: 10.1534/genetics.119.302936] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Accepted: 01/03/2020] [Indexed: 01/15/2023] Open
Abstract
Diploid germline cells must undergo two consecutive meiotic divisions before differentiating as haploid sex cells. During meiosis I, homologs pair and remain conjoined until segregation at anaphase. Drosophila melanogaster spermatocytes are unique in that the canonical events of meiosis I including synaptonemal complex formation, double-strand DNA breaks, and chiasmata are absent. Sex chromosomes pair at intergenic spacer sequences within the ribosomal DNA (rDNA). Autosomes pair at numerous euchromatic homologies, but not at heterochromatin, suggesting that pairing may be limited to specific sequences. However, previous work generated from genetic segregation assays or observations of late prophase I/prometaphase I chromosome associations fail to differentiate pairing from maintenance of pairing (conjunction). Here, we separately examined the capability of X euchromatin to pair and conjoin using an rDNA-deficient X and a series of Dp(1;Y) chromosomes. Genetic assays showed that duplicated X euchromatin can substitute for endogenous rDNA pairing sites. Segregation was not proportional to homology length, and pairing could be mapped to nonoverlapping sequences within a single Dp(1;Y) Using fluorescence in situ hybridization to early prophase I spermatocytes, we showed that pairing occurred with high fidelity at all homologies tested. Pairing was unaffected by the presence of X rDNA, nor could it be explained by rDNA magnification. By comparing genetic and cytological data, we determined that centromere proximal pairings were best at segregation. Segregation was dependent on the conjunction protein Stromalin in Meiosis, while the autosomal-specific Teflon was dispensable. Overall, our results suggest that pairing may occur at all homologies, but there may be sequence or positional requirements for conjunction.
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Affiliation(s)
- Christopher A Hylton
- Department of Biology, University of North Carolina, Greensboro, North Carolina 27402
| | - Katie Hansen
- Department of Biology, University of North Carolina, Greensboro, North Carolina 27402
| | - Andrew Bourgeois
- Department of Biology, University of North Carolina, Greensboro, North Carolina 27402
| | - John E Tomkiel Dean
- Department of Biology, University of North Carolina, Greensboro, North Carolina 27402
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16
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Kariyazono R, Oda A, Yamada T, Ohta K. Conserved HORMA domain-containing protein Hop1 stabilizes interaction between proteins of meiotic DNA break hotspots and chromosome axis. Nucleic Acids Res 2019; 47:10166-10180. [PMID: 31665745 PMCID: PMC6821256 DOI: 10.1093/nar/gkz754] [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: 06/17/2019] [Revised: 08/16/2019] [Accepted: 09/02/2019] [Indexed: 11/14/2022] Open
Abstract
HORMA domain-containing proteins such as Hop1 play crucial regulatory roles in various chromosomal functions. Here, we investigated roles of the fission yeast Hop1 in the formation of recombination-initiating meiotic DNA double strand breaks (DSBs). Meiotic DSB formation in fission yeast relies on multiple protein-protein interactions such as the one between the chromosome axial protein Rec10 and the DSB-forming complex subunit Rec15. Chromatin immunoprecipitation sequencing demonstrated that Hop1 is colocalized with both Rec10 and Rec15, and we observed physical interactions of Hop1 to Rec15 and Rec10. These results suggest that Hop1 promotes DSB formation by interacting with both axis components and the DSB-forming complex. We also show that Hop1 binding to DSB hotspots requires Rec15 and Rec10, while Hop1 axis binding requires Rec10 only, suggesting that Hop1 is recruited to the axis via Rec10, and to hotspots by hotspot-bound Rec15. Furthermore, we introduced separation-of-function Rec10 mutations, deficient for interaction with either Rec15 or Hop1. These single mutations and hop1Δ conferred only partial defects in meiotic recombination, while the combining the Rec15-binding-deficient rec10 mutation with hop1Δ synergistically reduced meiotic recombination, at least at a model hotspot. Taken together, Hop1 likely functions as a stabilizer for Rec15–Rec10 interaction to promote DSB formation.
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Affiliation(s)
- Ryo Kariyazono
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8654, Japan
| | - Arisa Oda
- Department of Life Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo, 153-8902, Japan
| | - Takatomi Yamada
- Department of Life Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo, 153-8902, Japan
| | - Kunihiro Ohta
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8654, Japan.,Department of Life Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo, 153-8902, Japan
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17
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Abstract
During meiosis, homologous chromosomes of a diploid cell are replicated and, without a second replication, are segregated during two nuclear divisions to produce four haploid cells (including discarded polar bodies in females of many species). Proper segregation of chromosomes at the first division requires in most species that homologous chromosomes be physically connected. Tension generated by connected chromosomes moving to opposite sides of the cell signals proper segregation. In the absence of the required connections, called crossovers, chromosomes often segregate randomly and produce aneuploid gametes and, thus, dead or disabled progeny. To be effective, crossovers must be properly distributed along chromosomes. Crossovers within or too near the centromere interfere with proper segregation; crossovers too near each other can ablate the required tension; and crossovers too concentrated in only one or a few regions would not re-assort most genetic characters important for evolution. Here, we discuss current knowledge of how the optimal distribution of crossovers is achieved in the fission yeast Schizosaccharomyces pombe, with reference to other well-studied species for comparison and illustration of the diversity of biology.
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Affiliation(s)
- Mridula Nambiar
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue North, Seattle, WA, 98112, United States
| | - Yu-Chien Chuang
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue North, Seattle, WA, 98112, United States
| | - Gerald R Smith
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue North, Seattle, WA, 98112, United States.
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18
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Hesse S, Zelkowski M, Mikhailova EI, Keijzer CJ, Houben A, Schubert V. Ultrastructure and Dynamics of Synaptonemal Complex Components During Meiotic Pairing and Synapsis of Standard (A) and Accessory (B) Rye Chromosomes. FRONTIERS IN PLANT SCIENCE 2019; 10:773. [PMID: 31281324 PMCID: PMC6596450 DOI: 10.3389/fpls.2019.00773] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 05/28/2019] [Indexed: 05/03/2023]
Abstract
During prophase I a meiosis-specific proteinaceous tripartite structure, the synaptonemal complex (SC), forms a scaffold to connect homologous chromosomes along their lengths. This process, called synapsis, is required in most organisms to promote recombination between homologs facilitating genetic variability and correct chromosome segregations during anaphase I. Recent studies in various organisms ranging from yeast to mammals identified several proteins involved in SC formation. However, the process of SC disassembly remains largely enigmatic. In this study we determined the structural changes during SC formation and disassembly in rye meiocytes containing accessory (B) chromosomes. The use of electron and super-resolution microscopy (3D-SIM) combined with immunohistochemistry and FISH allowed us to monitor the structural changes during prophase I. Visualization of the proteins ASY1, ZYP1, NSE4A, and HEI10 revealed an extensive SC remodeling during prophase I. The ultrastructural investigations of the dynamics of these four proteins showed that the SC disassembly is accompanied by the retraction of the lateral and axial elements from the central region of the SC. In addition, SC fragmentation and the formation of ball-like SC structures occur at late diakinesis. Moreover, we show that the SC composition of rye B chromosomes does not differ from that of the standard (A) chromosome complement. Our ultrastructural investigations indicate that the dynamic behavior of the studied proteins is involved in SC formation and synapsis. In addition, they fulfill also functions during desynapsis and chromosome condensation to realize proper recombination and homolog separation. We propose a model for the homologous chromosome behavior during prophase I based on the observed dynamics of ASY1, ZYP1, NSE4A, and HEI10.
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Affiliation(s)
- Susann Hesse
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, Seeland, Germany
| | - Mateusz Zelkowski
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, Seeland, Germany
| | - Elena I. Mikhailova
- N.I.Vavilov Institute of General Genetics, Russian Academy of Sciences, Saint-Petersburg State University, Saint-Petersburg, Russia
| | | | - Andreas Houben
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, Seeland, Germany
| | - Veit Schubert
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, Seeland, Germany
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19
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Abstract
The evolution of heteromorphic sex chromosomes has occurred independently many times in different lineages. The differentiation of sex chromosomes leads to dramatic changes in sequence composition and function and guides the evolutionary trajectory and utilization of genes in pivotal sex determination and reproduction roles. In addition, meiotic recombination and pairing mechanisms are key in orchestrating the resultant impact, retention and maintenance of heteromorphic sex chromosomes, as the resulting exposure of unpaired DNA at meiosis triggers ancient repair and checkpoint pathways. In this review, we summarize the different ways in which sex chromosome systems are organized at meiosis, how pairing is affected, and differences in unpaired DNA responses. We hypothesize that lineage specific differences in meiotic organization is not only a consequence of sex chromosome evolution, but that the establishment of epigenetic changes on sex chromosomes contributes toward their evolutionary conservation.
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Affiliation(s)
- Tasman Daish
- Comparative Genome Biology Laboratory, Department of Molecular and Biomedical Science, School of Biological Sciences, The University of Adelaide, Adelaide, SA, Australia
| | - Frank Grützner
- Comparative Genome Biology Laboratory, Department of Molecular and Biomedical Science, School of Biological Sciences, The University of Adelaide, Adelaide, SA, Australia.
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20
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Genetic interactions between the chromosome axis-associated protein Hop1 and homologous recombination determinants in Schizosaccharomyces pombe. Curr Genet 2018; 64:1089-1104. [PMID: 29550859 PMCID: PMC6153652 DOI: 10.1007/s00294-018-0827-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Accepted: 03/14/2018] [Indexed: 11/28/2022]
Abstract
Hop1 is a component of the meiosis-specific chromosome axis and belongs to the evolutionarily conserved family of HORMA domain proteins. Hop1 and its orthologs in higher eukaryotes are a major factor in promoting double-strand DNA break formation and inter-homolog recombination. In budding yeast and mammals, they are also involved in a meiotic checkpoint kinase cascade monitoring the completion of double-strand DNA break repair. We used the fission yeast, Schizosaccharomyces pombe, which lacks a canonical synaptonemal complex to test whether Hop1 has a role beyond supporting the generation of double-strand DNA breaks and facilitating inter-homolog recombination events. We determined how mutants of homologous recombination factors genetically interact with hop1, studied the role(s) of the HORMA domain of Hop1, and characterized a bio-informatically predicted interactor of Hop1, Aho1 (SPAC688.03c). Our observations indicate that in fission yeast, Hop1 does require its HORMA domain to support wild-type levels of meiotic recombination and localization to meiotic chromatin. Furthermore, we show that hop1∆ only weakly interacts genetically with mutants of homologous recombination factors, and in fission yeast likely has no major role beyond break formation and promoting inter-homolog events. We speculate that after the evolutionary loss of the synaptonemal complex, Hop1 likely has become less important for modulating recombination outcome during meiosis in fission yeast, and that this led to a concurrent rewiring of genetic pathways controlling meiotic recombination.
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21
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Chacón MR, Delivani P, Tolić IM. Meiotic Nuclear Oscillations Are Necessary to Avoid Excessive Chromosome Associations. Cell Rep 2017; 17:1632-1645. [PMID: 27806301 DOI: 10.1016/j.celrep.2016.10.014] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Revised: 07/26/2016] [Accepted: 10/04/2016] [Indexed: 10/20/2022] Open
Abstract
Pairing of homologous chromosomes is a crucial step in meiosis, which in fission yeast depends on nuclear oscillations. However, how nuclear oscillations help pairing is unknown. Here, we show that homologous loci typically pair when the spindle pole body is at the cell pole and the nucleus is elongated, whereas they unpair when the spindle pole body is in the cell center and the nucleus is round. Inhibition of oscillations demonstrated that movement is required for initial pairing and that prolonged association of loci leads to mis-segregation. The double-strand break marker Rec25 accumulates in elongated nuclei, indicating that prolonged chromosome stretching triggers recombinatory pathways leading to mis-segregation. Mis-segregation is rescued by overexpression of the Holliday junction resolvase Mus81, suggesting that prolonged pairing results in irresolvable recombination intermediates. We conclude that nuclear oscillations exhibit a dual role, promoting initial pairing and restricting the time of chromosome associations to ensure proper segregation.
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Affiliation(s)
- Mariola R Chacón
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, 01307 Dresden, Germany
| | - Petrina Delivani
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, 01307 Dresden, Germany
| | - Iva M Tolić
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, 01307 Dresden, Germany; Ruđer Bošković Institute, Bijenička Cesta 54, 10000 Zagreb, Croatia.
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22
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Ma L, Fowler KR, Martín-Castellanos C, Smith GR. Functional organization of protein determinants of meiotic DNA break hotspots. Sci Rep 2017; 7:1393. [PMID: 28469148 PMCID: PMC5431104 DOI: 10.1038/s41598-017-00742-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Accepted: 03/09/2017] [Indexed: 12/03/2022] Open
Abstract
During Schizosaccharomyces pombe meiotic prophase, homologous chromosomes are co-aligned by linear elements (LinEs) analogous to the axial elements of the synaptonemal complex (SC) in other organisms. LinE proteins also promote the formation of meiotic DNA double-strand breaks (DSBs), the precursors of cross-overs. Rec10 is required for essentially all DSBs and recombination, and three others (Rec25, Rec27, and Mug20) are protein determinants of DSB hotspots - they bind DSB hotspots with high specificity and are required for DSB formation there. These four LinE proteins co-localize in the nucleus in an interdependent way, suggesting they form a complex. We used random mutagenesis to uncover recombination-deficient missense mutants with novel properties. Some missense mutations changed essential residues conserved among Schizosaccharomyces species. DSB formation, gene conversion, and crossing-over were coordinately reduced in the mutants tested. Based on our mutant analysis, we revised the rec27 open reading frame: the new start codon is in the previously annotated first intron. Genetic and fluorescence-microscopy assays indicated that the Rec10 N- and C-terminal regions have complex interactions with Rec25. These mutants are a valuable resource to elucidate further how LinE proteins and the related SCs of other species regulate meiotic DSB formation to form crossovers crucial for meiosis.
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Affiliation(s)
- Lijuan Ma
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA, 98109, USA
| | - Kyle R Fowler
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA, 98109, USA
- Department of Microbiology and Immunology, University of California at San Francisco, San Francisco, CA, 94143, USA
| | - Cristina Martín-Castellanos
- Instituto de Biología Funcional y Genómica, CSIC/University of Salamanca, C/Zacarías González 2, 37007, Salamanca, Spain
| | - Gerald R Smith
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA, 98109, USA.
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23
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Snetselaar K, McCann M. Ustilago maydis, the corn smut fungus, has an unusual diploid mitotic stage. Mycologia 2017; 109:140-152. [DOI: 10.1080/00275514.2016.1274597] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Karen Snetselaar
- Department of Biology, Saint Joseph’s University, 5600 City Avenue, Philadelphia, Pennsylvania 19131
| | - Michael McCann
- Department of Biology, Saint Joseph’s University, 5600 City Avenue, Philadelphia, Pennsylvania 19131
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24
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Ding DQ, Haraguchi T, Hiraoka Y. A cohesin-based structural platform supporting homologous chromosome pairing in meiosis. Curr Genet 2016; 62:499-502. [PMID: 26856595 DOI: 10.1007/s00294-016-0570-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 01/26/2016] [Accepted: 01/28/2016] [Indexed: 12/14/2022]
Abstract
The pairing and recombination of homologous chromosomes during the meiotic prophase is necessary for the accurate segregation of chromosomes in meiosis. However, the mechanism by which homologous chromosomes achieve this pairing has remained an open question. Meiotic cohesins have been shown to affect chromatin compaction; however, the impact of meiotic cohesins on homologous pairing and the fine structures of cohesion-based chromatin remain to be determined. A recent report using live-cell imaging and super-resolution microscopy demonstrated that the lack of meiotic cohesins alters the chromosome axis structures and impairs the pairing of homologous chromosomes. These results suggest that meiotic cohesin-based chromosome axis structures are crucial for the pairing of homologous chromosomes.
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Affiliation(s)
- Da-Qiao Ding
- Advanced ICT Research Institute Kobe, National Institute of Information and Communications Technology, 588-2 Iwaoka, Iwaoka-cho, Nishi-ku, Kobe, 651-2492, Japan
| | - Tokuko Haraguchi
- Advanced ICT Research Institute Kobe, National Institute of Information and Communications Technology, 588-2 Iwaoka, Iwaoka-cho, Nishi-ku, Kobe, 651-2492, Japan
- Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka, Suita, 565-0871, Japan
| | - Yasushi Hiraoka
- Advanced ICT Research Institute Kobe, National Institute of Information and Communications Technology, 588-2 Iwaoka, Iwaoka-cho, Nishi-ku, Kobe, 651-2492, Japan.
- Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka, Suita, 565-0871, Japan.
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25
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Toselli-Mollereau E, Robellet X, Fauque L, Lemaire S, Schiklenk C, Klein C, Hocquet C, Legros P, N'Guyen L, Mouillard L, Chautard E, Auboeuf D, Haering CH, Bernard P. Nucleosome eviction in mitosis assists condensin loading and chromosome condensation. EMBO J 2016; 35:1565-81. [PMID: 27266525 DOI: 10.15252/embj.201592849] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2015] [Accepted: 05/05/2016] [Indexed: 12/15/2022] Open
Abstract
Condensins associate with DNA and shape mitotic chromosomes. Condensins are enriched nearby highly expressed genes during mitosis, but how this binding is achieved and what features associated with transcription attract condensins remain unclear. Here, we report that condensin accumulates at or in the immediate vicinity of nucleosome-depleted regions during fission yeast mitosis. Two transcriptional coactivators, the Gcn5 histone acetyltransferase and the RSC chromatin-remodelling complex, bind to promoters adjoining condensin-binding sites and locally evict nucleosomes to facilitate condensin binding and allow efficient mitotic chromosome condensation. The function of Gcn5 is closely linked to condensin positioning, since neither the localization of topoisomerase II nor that of the cohesin loader Mis4 is altered in gcn5 mutant cells. We propose that nucleosomes act as a barrier for the initial binding of condensin and that nucleosome-depleted regions formed at highly expressed genes by transcriptional coactivators constitute access points into chromosomes where condensin binds free genomic DNA.
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Affiliation(s)
- Esther Toselli-Mollereau
- Laboratory of Biology and Modelling of the Cell, Univ Lyon, ENS de Lyon, Univ Claude Bernard, CNRS UMR 5239, INSERM U1210, Lyon, France
| | - Xavier Robellet
- Laboratory of Biology and Modelling of the Cell, Univ Lyon, ENS de Lyon, Univ Claude Bernard, CNRS UMR 5239, INSERM U1210, Lyon, France
| | - Lydia Fauque
- Laboratory of Biology and Modelling of the Cell, Univ Lyon, ENS de Lyon, Univ Claude Bernard, CNRS UMR 5239, INSERM U1210, Lyon, France
| | - Sébastien Lemaire
- Laboratory of Biology and Modelling of the Cell, Univ Lyon, ENS de Lyon, Univ Claude Bernard, CNRS UMR 5239, INSERM U1210, Lyon, France
| | | | - Carlo Klein
- Cell Biology and Biophysics Unit, EMBL, Heidelberg, Germany
| | - Clémence Hocquet
- Laboratory of Biology and Modelling of the Cell, Univ Lyon, ENS de Lyon, Univ Claude Bernard, CNRS UMR 5239, INSERM U1210, Lyon, France
| | - Pénélope Legros
- Laboratory of Biology and Modelling of the Cell, Univ Lyon, ENS de Lyon, Univ Claude Bernard, CNRS UMR 5239, INSERM U1210, Lyon, France
| | - Lia N'Guyen
- Laboratory of Biology and Modelling of the Cell, Univ Lyon, ENS de Lyon, Univ Claude Bernard, CNRS UMR 5239, INSERM U1210, Lyon, France
| | - Léo Mouillard
- Laboratory of Biology and Modelling of the Cell, Univ Lyon, ENS de Lyon, Univ Claude Bernard, CNRS UMR 5239, INSERM U1210, Lyon, France
| | - Emilie Chautard
- Laboratory of Biology and Modelling of the Cell, Univ Lyon, ENS de Lyon, Univ Claude Bernard, CNRS UMR 5239, INSERM U1210, Lyon, France
| | - Didier Auboeuf
- Laboratory of Biology and Modelling of the Cell, Univ Lyon, ENS de Lyon, Univ Claude Bernard, CNRS UMR 5239, INSERM U1210, Lyon, France
| | | | - Pascal Bernard
- Laboratory of Biology and Modelling of the Cell, Univ Lyon, ENS de Lyon, Univ Claude Bernard, CNRS UMR 5239, INSERM U1210, Lyon, France
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26
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Patil S, Moeys S, von Dassow P, Huysman MJJ, Mapleson D, De Veylder L, Sanges R, Vyverman W, Montresor M, Ferrante MI. Identification of the meiotic toolkit in diatoms and exploration of meiosis-specific SPO11 and RAD51 homologs in the sexual species Pseudo-nitzschia multistriata and Seminavis robusta. BMC Genomics 2015; 16:930. [PMID: 26572248 PMCID: PMC4647503 DOI: 10.1186/s12864-015-1983-5] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2015] [Accepted: 10/04/2015] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Sexual reproduction is an obligate phase in the life cycle of most eukaryotes. Meiosis varies among organisms, which is reflected by the variability of the gene set associated to the process. Diatoms are unicellular organisms that belong to the stramenopile clade and have unique life cycles that can include a sexual phase. RESULTS The exploration of five diatom genomes and one diatom transcriptome led to the identification of 42 genes potentially involved in meiosis. While these include the majority of known meiosis-related genes, several meiosis-specific genes, including DMC1, could not be identified. Furthermore, phylogenetic analyses supported gene identification and revealed ancestral loss and recent expansion in the RAD51 family in diatoms. The two sexual species Pseudo-nitzschia multistriata and Seminavis robusta were used to explore the expression of meiosis-related genes: RAD21, SPO11-2, RAD51-A, RAD51-B and RAD51-C were upregulated during meiosis, whereas other paralogs in these families showed no differential expression patterns, suggesting that they may play a role during vegetative divisions. An almost identical toolkit is shared among Pseudo-nitzschia multiseries and Fragilariopsis cylindrus, as well as two species for which sex has not been observed, Phaeodactylum tricornutum and Thalassiosira pseudonana, suggesting that these two may retain a facultative sexual phase. CONCLUSIONS Our results reveal the conserved meiotic toolkit in six diatom species and indicate that Stramenopiles share major modifications of canonical meiosis processes ancestral to eukaryotes, with important divergences in each Kingdom.
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Affiliation(s)
- Shrikant Patil
- Stazione Zoologica Anton Dohrn, Villa Comunale 1, 80121, Naples, Italy.
| | - Sara Moeys
- Department of Biology, Protistology and Aquatic Ecology, Ghent University, 9000, Ghent, Belgium. .,Department of Plant Systems Biology, Flanders Institute for Biotechnology (VIB), 9052, Ghent, Belgium. .,Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052, Ghent, Belgium.
| | - Peter von Dassow
- Facultad de Ciencias Biológicas, Instituto Milenio de Oceanografía, Pontificia Universidad Católica de Chile, Santiago, Chile. .,UMI 3614, Evolutionary Biology and Ecology of Algae, CNRS-UPMC Sorbonne Universités, PUCCh, UACH, Station Biologique de Roscoff, Roscoff, France.
| | - Marie J J Huysman
- Department of Biology, Protistology and Aquatic Ecology, Ghent University, 9000, Ghent, Belgium. .,Department of Plant Systems Biology, Flanders Institute for Biotechnology (VIB), 9052, Ghent, Belgium. .,Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052, Ghent, Belgium.
| | - Daniel Mapleson
- The Genome Analysis Centre (TGAC), Norwich Research Park, Norwich, NR4 7UH, UK.
| | - Lieven De Veylder
- Department of Plant Systems Biology, Flanders Institute for Biotechnology (VIB), 9052, Ghent, Belgium. .,Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052, Ghent, Belgium.
| | - Remo Sanges
- Stazione Zoologica Anton Dohrn, Villa Comunale 1, 80121, Naples, Italy.
| | - Wim Vyverman
- Department of Biology, Protistology and Aquatic Ecology, Ghent University, 9000, Ghent, Belgium.
| | - Marina Montresor
- Stazione Zoologica Anton Dohrn, Villa Comunale 1, 80121, Naples, Italy.
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27
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Meiotic cohesin-based chromosome structure is essential for homologous chromosome pairing in Schizosaccharomyces pombe. Chromosoma 2015; 125:205-14. [PMID: 26511279 PMCID: PMC4830870 DOI: 10.1007/s00412-015-0551-8] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Revised: 10/07/2015] [Accepted: 10/09/2015] [Indexed: 11/30/2022]
Abstract
Chromosome structure is dramatically altered upon entering meiosis to establish chromosomal architectures necessary for the successful progression of meiosis-specific events. An early meiotic event involves the replacement of the non-SMC mitotic cohesins with their meiotic equivalents in most part of the chromosome, forming an axis on meiotic chromosomes. We previously demonstrated that the meiotic cohesin complex is required for chromosome compaction during meiotic prophase in the fission yeast Schizosaccharomyces pombe. These studies revealed that chromosomes are elongated in the absence of the meiotic cohesin subunit Rec8 and shortened in the absence of the cohesin-associated protein Pds5. In this study, using super-resolution structured illumination microscopy, we found that Rec8 forms a linear axis on chromosomes, which is required for the organized axial structure of chromatin during meiotic prophase. In the absence of Pds5, the Rec8 axis is shortened whereas chromosomes are widened. In rec8 or pds5 mutants, the frequency of homologous chromosome pairing is reduced. Thus, Rec8 and Pds5 play an essential role in building a platform to support the chromosome architecture necessary for the spatial alignment of homologous chromosomes.
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28
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Abstract
Faithful DNA replication is a prerequisite for cell proliferation. Several cytological studies have shown that chromosome structures alter in the S-phase of the cell cycle. However, the molecular mechanisms behind the alteration of chromosome structures associated with DNA replication have not been elucidated. Here, we investigated chromatin structures and acetylation of specific histone residues during DNA replication using the meiotic nucleus of the fission yeast Schizosaccharomyces pombe. The S. pombe meiotic nucleus provides a unique opportunity for measuring the levels of compaction of chromatin along the chromosome in a defined orientation. By direct measurement of chromatin compaction in living cells, we demonstrated that decompaction of chromatin occurs during meiotic DNA replication. This chromatin decompaction was suppressed by depletion of histone acetyltransferase Mst1 or by arginine substitution of specific lysine residues (K8 and K12) of histone H4. These results suggest that acetylation of histone H4 residues K8 and K12 plays a critical role in loosening chromatin structures during DNA replication.
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Zickler D, Kleckner N. Recombination, Pairing, and Synapsis of Homologs during Meiosis. Cold Spring Harb Perspect Biol 2015; 7:cshperspect.a016626. [PMID: 25986558 DOI: 10.1101/cshperspect.a016626] [Citation(s) in RCA: 485] [Impact Index Per Article: 53.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Recombination is a prominent feature of meiosis in which it plays an important role in increasing genetic diversity during inheritance. Additionally, in most organisms, recombination also plays mechanical roles in chromosomal processes, most notably to mediate pairing of homologous chromosomes during prophase and, ultimately, to ensure regular segregation of homologous chromosomes when they separate at the first meiotic division. Recombinational interactions are also subject to important spatial patterning at both early and late stages. Recombination-mediated processes occur in physical and functional linkage with meiotic axial chromosome structure, with interplay in both directions, before, during, and after formation and dissolution of the synaptonemal complex (SC), a highly conserved meiosis-specific structure that links homolog axes along their lengths. These diverse processes also are integrated with recombination-independent interactions between homologous chromosomes, nonhomology-based chromosome couplings/clusterings, and diverse types of chromosome movement. This review provides an overview of these diverse processes and their interrelationships.
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Affiliation(s)
- Denise Zickler
- Institut de Génétique et Microbiologie, UMR 8621, Université Paris-Sud, 91405 Orsay, France
| | - Nancy Kleckner
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts 02138
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Sakuno T, Watanabe Y. Phosphorylation of cohesin Rec11/SA3 by casein kinase 1 promotes homologous recombination by assembling the meiotic chromosome axis. Dev Cell 2015; 32:220-30. [PMID: 25579976 DOI: 10.1016/j.devcel.2014.11.033] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Revised: 11/11/2014] [Accepted: 11/21/2014] [Indexed: 11/24/2022]
Abstract
In meiosis, cohesin is required for sister chromatid cohesion, as well as meiotic chromosome axis assembly and recombination. However, mechanisms underlying the multifunctional nature of cohesin remain elusive. Here, we show that fission yeast casein kinase 1 (CK1) plays a crucial role in assembling the meiotic chromosome axis (so-called linear element: LinE) and promoting recombination. An in vitro phosphorylation screening assay identified meiotic cohesin subunit Rec11/SA3 as an excellent substrate of CK1. The phosphorylation of Rec11 by CK1 mediates the interaction with the Rec10/Red1/SCP2 axis component, a key step in meiotic chromosome axis assembly, and is dispensable for sister chromatid cohesion. Crucially, the expression of Rec11-Rec10 fusion protein nearly completely bypasses the requirement for CK1 or cohesin phosphorylation for LinE assembly and recombination. This study uncovers a central mechanism of the cohesin-dependent assembly of the meiotic chromosome axis and recombination apparatus that acts independently of sister chromatid cohesion.
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Affiliation(s)
- Takeshi Sakuno
- Laboratory of Chromosome Dynamics, Institute of Molecular and Cellular Biosciences, University of Tokyo, Yayoi, Tokyo 113-0032, Japan; Graduate School of Agricultural and Life Sciences, University of Tokyo, Yayoi, Tokyo 113-0032, Japan
| | - Yoshinori Watanabe
- Laboratory of Chromosome Dynamics, Institute of Molecular and Cellular Biosciences, University of Tokyo, Yayoi, Tokyo 113-0032, Japan; Graduate School of Agricultural and Life Sciences, University of Tokyo, Yayoi, Tokyo 113-0032, Japan; Graduate School of Science, University of Tokyo, Yayoi, Tokyo 113-0032, Japan.
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31
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Ruan K, Yamamoto TG, Asakawa H, Chikashige Y, Masukata H, Haraguchi T, Hiraoka Y. Meiotic nuclear movements in fission yeast are regulated by the transcription factor Mei4 downstream of a Cds1-dependent replication checkpoint pathway. Genes Cells 2014; 20:160-72. [PMID: 25492408 PMCID: PMC4359684 DOI: 10.1111/gtc.12207] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Accepted: 10/29/2014] [Indexed: 12/30/2022]
Abstract
In meiosis, the fission yeast nucleus displays an elongated morphology, moving back and forth within the cell; these nuclear movements continue for approximately 2 h before meiotic nuclear divisions. Meiotic DNA replication occurs in an early phase of the nuclear movements and is followed by meiotic prophase. Here we report that in mutants deficient in meiotic DNA replication, the duration of nuclear movements is strikingly prolonged to four to 5 h. We found that this prolongation was caused by the Cds1-dependent replication checkpoint, which represses expression of the mei4+ gene encoding a meiosis-specific transcription factor. In the absence of Mei4, nuclear movements persisted for more than 8 h. In contrast, overproduction of Mei4 accelerated termination of nuclear movements to approximately 30 min. These results show that Mei4 is involved in the termination of nuclear movements and that Mei4-mediated regulatory pathways link a DNA replication checkpoint to the termination of nuclear movements.
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Affiliation(s)
- Kun Ruan
- Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka, Suita, 565-0871, Japan
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32
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Estreicher A, Lorenz A, Loidl J. Mug20, a novel protein associated with linear elements in fission yeast meiosis. Curr Genet 2012; 58:119-27. [PMID: 22362333 PMCID: PMC3310140 DOI: 10.1007/s00294-012-0369-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2012] [Revised: 02/07/2012] [Accepted: 02/10/2012] [Indexed: 11/27/2022]
Abstract
In the fission yeast, Schizosaccharomyces pombe, homologous chromosomes efficiently pair and recombine during meiotic prophase without forming a canonical synaptonemal complex (SC). Instead, it features simpler filamentous structures, the so-called linear elements (LinEs), which bear some resemblance to the axial/lateral element subunits of the SC. LinEs are required for wild-type recombination frequency. Here, we recognized Mug20, the product of a meiotically upregulated gene, as a LinE-associated protein. GFP-tagged Mug20 and anti-Mug20 antibody co-localized completely with Rec10, one of the major constituents of LinEs. In the absence of Mug20, LinEs failed to elongate beyond their initial state of nuclear dots. Foci of recombination protein Rad51 and genetic recombination were reduced. Since meiotic DNA double-strand breaks (DSBs), which initiate recombination, are induced at sites of preformed LinEs, we suggest that reduced recombination is a consequence of incomplete LinE extension. Therefore, we propose that Mug20 is required to extend LinEs from their sites of origin and thereby to increase DSB proficient regions on chromosomes.
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Affiliation(s)
- Anna Estreicher
- Department of Chromosome Biology, Center for Molecular Biology of the University of Vienna (MFPL), Dr. Bohr Gasse 1, 1030 Vienna, Austria
| | - Alexander Lorenz
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU UK
| | - Josef Loidl
- Department of Chromosome Biology, Center for Molecular Biology of the University of Vienna (MFPL), Dr. Bohr Gasse 1, 1030 Vienna, Austria
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33
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Hultén MA. On the origin of crossover interference: A chromosome oscillatory movement (COM) model. Mol Cytogenet 2011; 4:10. [PMID: 21477316 PMCID: PMC3103480 DOI: 10.1186/1755-8166-4-10] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2011] [Accepted: 04/08/2011] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND It is now nearly a century since it was first discovered that crossovers between homologous parental chromosomes, originating at the Prophase stage of Meiosis I, are not randomly placed. In fact, the number and distribution of crossovers are strictly regulated with crossovers/chiasmata formed in optimal positions along the length of individual chromosomes, facilitating regular chromosome segregation at the first meiotic division. In spite of much research addressing this question, the underlying mechanism(s) for the phenomenon called crossover/chiasma interference is/are still unknown; and this constitutes an outstanding biological enigma. RESULTS The Chromosome Oscillatory Movement (COM) model for crossover/chiasma interference implies that, during Prophase of Meiosis I, oscillatory movements of the telomeres (attached to the nuclear membrane) and the kinetochores (within the centromeres) create waves along the length of chromosome pairs (bivalents) so that crossing-over and chiasma formation is facilitated by the proximity of parental homologs induced at the nodal regions of the waves thus created. This model adequately explains the salient features of crossover/chiasma interference, where (1) there is normally at least one crossover/chiasma per bivalent, (2) the number is correlated to bivalent length, (3) the positions are dependent on the number per bivalent, (4) interference distances are on average longer over the centromere than along chromosome arms, and (5) there are significant changes in carriers of structural chromosome rearrangements. CONCLUSIONS The crossover/chiasma frequency distribution in humans and mice with normal karyotypes as well as in carriers of structural chromosome rearrangements are those expected on the COM model. Further studies are underway to analyze mechanical/mathematical aspects of this model for the origin of crossover/chiasma interference, using string replicas of the homologous chromosomes at the Prophase stage of Meiosis I. The parameters to vary in this type of experiment will include: (1) the mitotic karyotype, i.e. ranked length and centromere index of the chromosomes involved, (2) the specific bivalent/multivalent length and flexibility, dependent on the way this structure is positioned within the nucleus and the size of the respective meiocyte nuclei, (3) the frequency characteristics of the oscillatory movements at respectively the telomeres and the kinetochores.
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Affiliation(s)
- Maj A Hultén
- Department of Molecular Medicine and Surgery and Center for Molecular Medicine, CMM L8:02, Karolinska Institutet, Karolinska University Hospital, Solna, S-17 1 76 Stockholm, Sweden.
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Mallela S, Latypov V, Kohli J. Rec10- and Rec12-independent recombination in meiosis of Schizosaccharomyces pombe. Yeast 2011; 28:405-21. [PMID: 21387406 DOI: 10.1002/yea.1847] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2010] [Accepted: 02/03/2011] [Indexed: 11/11/2022] Open
Abstract
The Rec10 protein, a component of the linear elements forming along sister chromatids in meiotic prophase of Schizosaccharomyces pombe, plays an important role in the activation of Rec12 for double-strand break formation, and thus the initiation of recombination between homologous chromosomes. Recombination between homologous chromosomes was moderately reduced in homozygous crosses of the C-terminal truncation mutant rec10-155 and strongly in the full deletion allele rec10-175. Both alleles were also tested in two assays for intrachromosomal recombination (PS1 and VL1) and showed only slight reductions, while deletion of rec12 led to a 13-fold reduction. The even stronger reductions in rec10 rec12 double deletion crosses indicate partially redundant functions of Rec10 and Rec12 in the initiation of intrachromosomal recombination. A low level of double-strand breaks has been detected in rec10-175 meiosis at the mbs1 hotspot of recombination, and spore viability in the double mutant was also lower than in the single-deletion mutants. Low levels of apparent crossover and conversion between homologous chromosomes in the absence of Rec12 have been quantified using a newly developed assay. The results also indicate that the functions of Rec10 differ in several respects from those of its distant homologue Red1 in Saccharomyces cerevisiae, including interactions with Hop1 and Mek1 for promotion of recombination between homologues at the expense of sister chromatid recombination.
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Affiliation(s)
- Shamroop Mallela
- Institute of Cell Biology, University of Berne, Baltzer-Strasse 4, Berne, Switzerland
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35
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Abstract
Topoisomerases can release topological stress and resolve DNA catenanes by a DNA strand breakage and re-ligation mechanism. During the lifetime of the DNA break, the topoisomerase remains covalently linked to the DNA and removes itself when the break is re-ligated. While the lifetime of a covalent topoisomerase-DNA complex is usually short, several clinically important cancer drugs kill cancer cells by inhibiting the removal of covalently linked topoisomerases. The topoisomerase-like protein Spo11 is responsible for meiotic double strand break formation. Spo11 is not able to remove itself and is removed by nucleolytic cleavage. This chapter describes a method which allows the reproducible and quantitative detection of proteins covalently bound to the DNA.
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Affiliation(s)
- Edgar Hartsuiker
- North West Cancer Research Fund Institute, Bangor University, LL57 2UW, Bangor, UK.
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36
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Abstract
Sister chromatids are held together from the time of their formation in S phase until they segregate in anaphase by the cohesin complex. In meiosis of most organisms, the mitotic Mcd1/Scc1/Rad21 subunit of the cohesin complex is largely replaced by its paralog named Rec8. This article reviews the specialized functions of Rec8 that are crucial for diverse aspects of chromosome dynamics in meiosis, and presents some speculations relating to meiotic chromosome organization.
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37
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Steiner S, Kohli J, Ludin K. Functional interactions among members of the meiotic initiation complex in fission yeast. Curr Genet 2010; 56:237-49. [PMID: 20364342 DOI: 10.1007/s00294-010-0296-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2009] [Revised: 03/11/2010] [Accepted: 03/11/2010] [Indexed: 12/11/2022]
Abstract
DNA double-strand breaks (DSBs) initiate meiotic recombination in Schizosaccharomyces pombe and in other organisms. The Rec12 protein catalyzes the formation of these DSBs in concert with a multitude of accessory proteins the role of which in this process remains to be discovered. In an all-to-all yeast two-hybrid matrix analysis, we discovered new interactions among putative members of the meiotic recombination initiation complex. We found that Rec7, an axial-element associated protein with homologies to Saccharomyces cerevisiae Rec114, is interacting with Rec24. Rec7 and Rec24 also co-immunoprecipitate in S. pombe during meiosis. An amino acid change in a conserved, C-terminal phenylalanine in Rec7, F325A interrupts the interaction with Rec24. Moreover, rec7F325A shows a recombination deficiency comparable to rec7Delta. Another interaction was detected between Rec12 and Rec14, the orthologs of which in S. cerevisiae Spo11 and Ski8 interact accordingly. Amino acid changes Rec12Q308A and Rec12R309A disrupt the interaction with Rec14, like the according amino acid changes Spo11Q376A and Spo11RE377AA loose the interaction with Ski8. Both amino acid changes in Rec12 reveal a recombination deficient rec12 (-) phenotype. We propose that both Rec7-Rec24 and Rec12-Rec14 form subcomplexes of the meiotic recombination initiation complex.
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Affiliation(s)
- Silvia Steiner
- Institute of Cell Biology, University of Bern, Switzerland
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38
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Latypov V, Rothenberg M, Lorenz A, Octobre G, Csutak O, Lehmann E, Loidl J, Kohli J. Roles of Hop1 and Mek1 in meiotic chromosome pairing and recombination partner choice in Schizosaccharomyces pombe. Mol Cell Biol 2010; 30:1570-81. [PMID: 20123974 PMCID: PMC2838064 DOI: 10.1128/mcb.00919-09] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2009] [Revised: 08/26/2009] [Accepted: 01/19/2010] [Indexed: 11/20/2022] Open
Abstract
Synaptonemal complex (SC) proteins Hop1 and Mek1 have been proposed to promote homologous recombination in meiosis of Saccharomyces cerevisiae by establishment of a barrier against sister chromatid recombination. Therefore, it is interesting to know whether the homologous proteins play a similar role in Schizosaccharomyces pombe. Unequal sister chromatid recombination (USCR) was found to be increased in hop1 and mek1 single and double deletion mutants in assays for intrachromosomal recombination (ICR). Meiotic intergenic (crossover) and intragenic (conversion) recombination between homologous chromosomes was reduced. Double-strand break (DSB) levels were also lowered. Notably, deletion of hop1 restored DSB repair in rad50S meiosis. This may indicate altered DSB repair kinetics in hop1 and mek1 deletion strains. A hypothesis is advanced proposing transient inhibition of DSB processing by Hop1 and Mek1 and thus providing more time for repair by interaction with the homologous chromosome. Loss of Hop1 and Mek1 would then result in faster repair and more interaction with the sister chromatid. Thus, in S. pombe meiosis, where an excess of sister Holliday junction over homologous Holliday junction formation has been demonstrated, Hop1 and Mek1 possibly enhance homolog interactions to ensure wild-type level of crossover formation rather than inhibiting sister chromatid interactions.
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Affiliation(s)
- Vitaly Latypov
- Institute of Cell Biology, University of Berne, CH-3012 Berne, Switzerland, Department of Chromosome Biology, University of Vienna, 1030 Vienna, Austria
| | - Maja Rothenberg
- Institute of Cell Biology, University of Berne, CH-3012 Berne, Switzerland, Department of Chromosome Biology, University of Vienna, 1030 Vienna, Austria
| | - Alexander Lorenz
- Institute of Cell Biology, University of Berne, CH-3012 Berne, Switzerland, Department of Chromosome Biology, University of Vienna, 1030 Vienna, Austria
| | - Guillaume Octobre
- Institute of Cell Biology, University of Berne, CH-3012 Berne, Switzerland, Department of Chromosome Biology, University of Vienna, 1030 Vienna, Austria
| | - Ortansa Csutak
- Institute of Cell Biology, University of Berne, CH-3012 Berne, Switzerland, Department of Chromosome Biology, University of Vienna, 1030 Vienna, Austria
| | - Elisabeth Lehmann
- Institute of Cell Biology, University of Berne, CH-3012 Berne, Switzerland, Department of Chromosome Biology, University of Vienna, 1030 Vienna, Austria
| | - Josef Loidl
- Institute of Cell Biology, University of Berne, CH-3012 Berne, Switzerland, Department of Chromosome Biology, University of Vienna, 1030 Vienna, Austria
| | - Jürg Kohli
- Institute of Cell Biology, University of Berne, CH-3012 Berne, Switzerland, Department of Chromosome Biology, University of Vienna, 1030 Vienna, Austria
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Rothenberg M, Kohli J, Ludin K. Ctp1 and the MRN-complex are required for endonucleolytic Rec12 removal with release of a single class of oligonucleotides in fission yeast. PLoS Genet 2009; 5:e1000722. [PMID: 19911044 PMCID: PMC2768786 DOI: 10.1371/journal.pgen.1000722] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2009] [Accepted: 10/15/2009] [Indexed: 11/18/2022] Open
Abstract
DNA double-strand breaks (DSBs) are formed during meiosis by the action of the topoisomerase-like Spo11/Rec12 protein, which remains covalently bound to the 5' ends of the broken DNA. Spo11/Rec12 removal is required for resection and initiation of strand invasion for DSB repair. It was previously shown that budding yeast Spo11, the homolog of fission yeast Rec12, is removed from DNA by endonucleolytic cleavage. The release of two Spo11 bound oligonucleotide classes, heterogeneous in length, led to the conjecture of asymmetric cleavage. In fission yeast, we found only one class of oligonucleotides bound to Rec12 ranging in length from 17 to 27 nucleotides. Ctp1, Rad50, and the nuclease activity of Rad32, the fission yeast homolog of Mre11, are required for endonucleolytic Rec12 removal. Further, we detected no Rec12 removal in a rad50S mutant. However, strains with additional loss of components localizing to the linear elements, Hop1 or Mek1, showed some Rec12 removal, a restoration depending on Ctp1 and Rad32 nuclease activity. But, deletion of hop1 or mek1 did not suppress the phenotypes of ctp1Delta and the nuclease dead mutant (rad32-D65N). We discuss what consequences for subsequent repair a single class of Rec12-oligonucleotides may have during meiotic recombination in fission yeast in comparison to two classes of Spo11-oligonucleotides in budding yeast. Furthermore, we hypothesize on the participation of Hop1 and Mek1 in Rec12 removal.
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Affiliation(s)
| | - Jürg Kohli
- Institute of Cell Biology, University of Bern, Switzerland
| | - Katja Ludin
- Institute of Cell Biology, University of Bern, Switzerland
- * E-mail:
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40
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Spirek M, Estreicher A, Csaszar E, Wells J, McFarlane RJ, Watts FZ, Loidl J. SUMOylation is required for normal development of linear elements and wild-type meiotic recombination in Schizosaccharomyces pombe. Chromosoma 2009; 119:59-72. [PMID: 19756689 DOI: 10.1007/s00412-009-0241-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2009] [Revised: 07/24/2009] [Accepted: 07/27/2009] [Indexed: 01/20/2023]
Abstract
In the fission yeast, Schizosaccharomyces pombe, synaptonemal complexes (SCs) are not formed during meiotic prophase. However, structures resembling the axial elements of SCs, the so-called linear elements (LinEs) appear. By in situ immunostaining, we found Pmt3 (S. pombe's SUMO protein) transiently along LinEs, suggesting that SUMOylation of some component(s) of LinEs occurs during meiosis. Mutation of the SUMO ligase Pli1 caused aberrant LinE formation and reduced genetic recombination indicating a role for SUMOylation of LinEs for the regulation of meiotic recombination. Western blot analysis of TAP-tagged Rec10 demonstrated that there is a Pli1-dependent posttranslational modification of this protein, which is a major LinE component and a distant homolog of the SC protein Red1. Mass spectrometry (MS) analysis revealed that Rec10 is both phosphorylated and ubiquitylated, but no evidence for SUMOylation of Rec10 was found. These findings indicate that the regulation of LinE and Rec10 function is modulated by Pli1-dependent SUMOylation of LinE protein(s) which directly or indirectly regulates Rec10 modification. On the side, MS analysis confirmed the interaction of Rec10 with the known LinE components Rec25, Rec27, and Hop1 and identified the meiotically upregulated protein Mug20 as a novel putative LinE-associated protein.
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Affiliation(s)
- Mario Spirek
- Department of Chromosome Biology, Center for Molecular Biology of the University of Vienna (MFPL), Dr. Bohr Gasse 1, 1030, Vienna, Austria
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41
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Abstract
Controlling the loading of Rad51 onto DNA is important for governing when and how homologous recombination is used. Here we use a combination of genetic assays and indirect immunofluorescence to show that the F-box DNA helicase (Fbh1) functions in direct opposition to the Rad52 orthologue Rad22 to curb Rad51 loading onto DNA in fission yeast. Surprisingly, this activity is unnecessary for limiting spontaneous direct-repeat recombination. Instead it appears to play an important role in preventing recombination when replication forks are blocked and/or broken. When overexpressed, Fbh1 specifically reduces replication fork block-induced recombination, as well as the number of Rad51 nuclear foci that are induced by replicative stress. These abilities are dependent on its DNA helicase/translocase activity, suggesting that Fbh1 exerts its control on recombination by acting as a Rad51 disruptase. In accord with this, overexpression of Fbh1 also suppresses the high levels of recombinant formation and Rad51 accumulation at a site-specific replication fork barrier in a strain lacking the Rad51 disruptase Srs2. Similarly overexpression of Srs2 suppresses replication fork block-induced gene conversion events in an fbh1Delta mutant, although an inability to suppress deletion events suggests that Fbh1 has a distinct functionality, which is not readily substituted by Srs2.
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42
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Alternative induction of meiotic recombination from single-base lesions of DNA deaminases. Genetics 2009; 182:41-54. [PMID: 19237686 DOI: 10.1534/genetics.109.101683] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Meiotic recombination enhances genetic diversity as well as ensures proper segregation of homologous chromosomes, requiring Spo11-initiated double-strand breaks (DSBs). DNA deaminases act on regions of single-stranded DNA and deaminate cytosine to uracil (dU). In the immunoglobulin locus, this lesion will initiate point mutations, gene conversion, and DNA recombination. To begin to delineate the effect of induced base lesions on meiosis, we analyzed the effect of expressing DNA deaminases (activation-induced deaminase, AID, and APOBEC3C) in germ cells. We show that meiotic dU:dG lesions can partially rescue a spo11Delta phenotype in yeast and worm. In rec12 Schizosaccharomyces pombe, AID expression increased proper chromosome segregation, thereby enhancing spore viability, and induced low-frequency meiotic crossovers. Expression of AID in the germ cells of Caenorhabditis elegans spo-11 induced meiotic RAD-51 foci formation and chromosomal bivalency and segregation, as well as an increase in viability. RNAi experiments showed that this rescue was dependent on uracil DNA-glycosylase (Ung). Furthermore, unlike ionizing radiation-induced spo-11 rescue, AID expression did not induce large numbers of DSBs during the rescue. This suggests that the products of DNA deamination and base excision repair, such as uracil, an abasic site, or a single-stranded nick, are sufficient to initiate and alter meiotic recombination in uni- and multicellular organisms.
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43
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Ctp1CtIP and Rad32Mre11 nuclease activity are required for Rec12Spo11 removal, but Rec12Spo11 removal is dispensable for other MRN-dependent meiotic functions. Mol Cell Biol 2009; 29:1671-81. [PMID: 19139281 DOI: 10.1128/mcb.01182-08] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The evolutionarily conserved Mre11/Rad50/Nbs1 (MRN) complex is involved in various aspects of meiosis. Whereas available evidence suggests that the Mre11 nuclease activity might be responsible for Spo11 removal in Saccharomyces cerevisiae, this has not been confirmed experimentally. This study demonstrates for the first time that Mre11 (Schizosaccharomyces pombe Rad32(Mre11)) nuclease activity is required for the removal of Rec12(Spo11). Furthermore, we show that the CtIP homologue Ctp1 is required for Rec12(Spo11) removal, confirming functional conservation between Ctp1(CtIP) and the more distantly related Sae2 protein from Saccharomyces cerevisiae. Finally, we show that the MRN complex is required for meiotic recombination, chromatin remodeling at the ade6-M26 recombination hot spot, and formation of linear elements (which are the equivalent of the synaptonemal complex found in other eukaryotes) but that all of these functions are proficient in a rad50S mutant, which is deficient for Rec12(Spo11) removal. These observations suggest that the conserved role of the MRN complex in these meiotic functions is independent of Rec12(Spo11) removal.
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44
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Abstract
The fission yeast, Schizosaccharomyces pombe, much like the budding yeast, is a particularly well-suited model organism for genetic research. However, the miniscule size of both yeasts' nuclei has hindered their success as research models for cytologists. A solution to this problem is provided by the spreading of nuclei, which increases their volume and allows for a better spatial resolution of nuclear contents. Here we describe nuclear spreading in fission yeast. Spreading of meiotic nuclei is particularly helpful in exposing the linear elements (LinEs), which are the fission yeasts' rudimentary version of the synaptonemal complex. Although the LinEs' role is still not fully understood, they serve as important meiotic hallmarks and their presence and morphology can be used in characterizing meiotic mutants. We first describe methods to induce meiosis in liquid cell cultures, then outline a method to break down cell and nuclear membranes by detergent treatment to release chromatin on cytological slides, and finally provide a set of protocols for analyzing these nuclei by immunostaining and fluorescence in situ hybridization (FISH), and by electron microscopy.
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Affiliation(s)
- Josef Loidl
- Department of Chromosome Biology, Center for Molecular Biology, University of Vienna, Vienna, Austria
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45
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Abstract
The fission yeast Schizosaccharomyces pombe has many biological characteristics that make it an ideal model organism for the study of meiosis. A nearly synchronous meiosis is one of the most important. Under certain environmental and genetic conditions, large cultures of S. pombe can be induced to undergo meiosis in a timely and predictable manner that allows for changes in the DNA to be observed and analyzed by gel electrophoresis. Initiation of meiotic recombination via programmed DNA double-strand breaks, the formation of joint molecule recombination intermediates, and the resolution of these intermediates into crossover DNA products can all be seen with consistent timing during the progression of a synchronous meiotic induction. The timing of recombination events, the genetic requirements for the formation and disappearance of recombination intermediates, and the analysis of the DNA structures of those intermediates allow a comparison of meiotic recombination in fission yeast with that in the only other species similarly studied, the budding yeast Saccharomyces cerevisiae.
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Doll E, Molnar M, Cuanoud G, Octobre G, Latypov V, Ludin K, Kohli J. Cohesin and recombination proteins influence the G1-to-S transition in azygotic meiosis in Schizosaccharomyces pombe. Genetics 2008; 180:727-40. [PMID: 18780734 PMCID: PMC2567376 DOI: 10.1534/genetics.108.092619] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2008] [Accepted: 08/05/2008] [Indexed: 11/18/2022] Open
Abstract
To determine whether recombination and/or sister-chromatid cohesion affect the timing of meiotic prophase events, the horsetail stage and S phase were analyzed in Schizosaccharomyces pombe strains carrying mutations in the cohesin genes rec8 or rec11, the linear element gene rec10, the pairing gene meu13, the double-strand-break formation genes rec6, rec7, rec12, rec14, rec15, and mde2, and the recombination gene dmc1. The double-mutant strains rec8 rec11 and rec8 rec12 were also assayed. Most of the single and both double mutants showed advancement of bulk DNA synthesis, start of nuclear movement (horsetail stage), and meiotic divisions by up to 2 hr. Only mde2 and dmc1 deletion strains showed wild-type timing. Contrasting behavior was observed for rec8 deletions (delayed by 1 hr) compared to a rec8 point mutation (advanced by 1 hr). An hypothesis for the role of cohesin and recombination proteins in the control of the G(1)-to-S transition is proposed. Finally, differences between azygotic meiosis and two other types of fission yeast meiosis (zygotic and pat1-114 meiosis) are discussed with respect to possible control steps in meiotic G(1).
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Affiliation(s)
- Eveline Doll
- Institute of Cell Biology, University of Berne, CH-3012 Berne, Switzerland
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Holloman WK, Schirawski J, Holliday R. The homologous recombination system of Ustilago maydis. Fungal Genet Biol 2008; 45 Suppl 1:S31-9. [PMID: 18502156 PMCID: PMC2583931 DOI: 10.1016/j.fgb.2008.04.006] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2008] [Revised: 04/09/2008] [Accepted: 04/11/2008] [Indexed: 12/26/2022]
Abstract
Homologous recombination is a high fidelity, template-dependent process that is used in repair of damaged DNA, recovery of broken replication forks, and disjunction of homologous chromosomes in meiosis. Much of what is known about recombination genes and mechanisms comes from studies on baker's yeast. Ustilago maydis, a basidiomycete fungus, is distant evolutionarily from baker's yeast and so offers the possibility of gaining insight into recombination from an alternative perspective. Here we have surveyed the genome of U. maydis to determine the composition of its homologous recombination system. Compared to baker's yeast, there are fundamental differences in the function as well as in the repertoire of dedicated components. These include the use of a BRCA2 homolog and its modifier Dss1 rather than Rad52 as a mediator of Rad51, the presence of only a single Rad51 paralog, and the absence of Dmc1 and auxiliary meiotic proteins.
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Affiliation(s)
- William K Holloman
- Cornell University Weill Medical College, Department of Microbiology and Immunology, NY 10021, USA.
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The Rad52 homologs Rad22 and Rti1 of Schizosaccharomyces pombe are not essential for meiotic interhomolog recombination, but are required for meiotic intrachromosomal recombination and mating-type-related DNA repair. Genetics 2008; 178:2399-412. [PMID: 18430957 DOI: 10.1534/genetics.107.085696] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Proteins of the RAD52 epistasis group play an essential role in repair of some types of DNA damage and genetic recombination. In Schizosaccharomyces pombe, Rad22 (a Rad52 ortholog) has been shown to be as necessary for repair and recombination events during vegetative growth as its Saccharomyces cerevisiae counterpart. This finding contrasts with previous reports where, due to suppressor mutations in the fbh1 gene, rad22 mutants did not display a severe defect. We have analyzed the roles of Rad22 and Rti1, another Rad52 homolog, during meiotic recombination and meiosis in general. Both proteins play an important role in spore viability. During meiotic prophase I, they partially colocalize and partially localize to Rad51 foci and linear elements. Genetic analysis showed that meiotic interchromosomal crossover and conversion events were unexpectedly not much affected by deletion of either or both genes. A strong decrease of intrachromosomal recombination assayed by a gene duplication construct was observed. Therefore, we propose that the most important function of Rad22 and Rti1 in S. pombe meiosis is repair of double-strand breaks with involvement of the sister chromatids. In addition, a novel mating-type-related repair function of Rad22 specific to meiosis and spore germination is described.
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Davis L, Rozalén AE, Moreno S, Smith GR, Martín-Castellanos C. Rec25 and Rec27, novel linear-element components, link cohesin to meiotic DNA breakage and recombination. Curr Biol 2008; 18:849-54. [PMID: 18514516 PMCID: PMC3119532 DOI: 10.1016/j.cub.2008.05.025] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2008] [Revised: 04/18/2008] [Accepted: 05/02/2008] [Indexed: 01/12/2023]
Abstract
Meiosis is a specialized nuclear division by which sexually reproducing diploid organisms generate haploid gametes. Recombination between homologous chromosomes facilitates accurate meiotic chromosome segregation and is initiated by DNA double-strand breaks (DSBs) made by the conserved topoisomerase-like protein Spo11 (Rec12 in fission yeast), but DSBs are not evenly distributed across the genome. In Schizosaccharomyces pombe, proteinaceous structures known as linear elements (LinEs) are formed during meiotic prophase. The meiosis-specific cohesin subunits Rec8 and Rec11 are essential for DSB formation in some regions of the genome, as well as for formation of LinEs or the related synaptonemal complex (SC) in other eukaryotes. Proteins required for DSB formation decorate LinEs, and mutants lacking Rec10, a major component of LinEs, are completely defective for recombination. Although recombination may occur in the context of LinEs, it is not well understood how Rec10 is loaded onto chromosomes. We describe two novel components of LinEs in fission yeast, Rec25 and Rec27. Comparisons of rec25Delta, rec27Delta, and rec10Delta mutants suggest multiple pathways to load Rec10. In the major pathway, Rec10 is loaded, together with Rec25 and Rec27, in a Rec8-dependent manner with subsequent region-specific effects on recombination.
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Affiliation(s)
- Luther Davis
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, U.S.A
| | - Ana E. Rozalén
- Instituto de Biología Molecular y Celular del Cáncer, CSIC/Universidad de Salamanca, Campus Miguel de Unamuno, 37007 Salamanca, Spain
| | - Sergio Moreno
- Instituto de Biología Molecular y Celular del Cáncer, CSIC/Universidad de Salamanca, Campus Miguel de Unamuno, 37007 Salamanca, Spain
| | - Gerald R. Smith
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, U.S.A
| | - Cristina Martín-Castellanos
- Instituto de Biología Molecular y Celular del Cáncer, CSIC/Universidad de Salamanca, Campus Miguel de Unamuno, 37007 Salamanca, Spain
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50
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Bernard P, Schmidt CK, Vaur S, Dheur S, Drogat J, Genier S, Ekwall K, Uhlmann F, Javerzat JP. Cell-cycle regulation of cohesin stability along fission yeast chromosomes. EMBO J 2008; 27:111-21. [PMID: 18079700 PMCID: PMC2206136 DOI: 10.1038/sj.emboj.7601955] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2007] [Accepted: 11/16/2007] [Indexed: 02/08/2023] Open
Abstract
Sister chromatid cohesion is mediated by cohesin, but the process of cohesion establishment during S-phase is still enigmatic. In mammalian cells, cohesin binding to chromatin is dynamic in G1, but becomes stabilized during S-phase. Whether the regulation of cohesin stability is integral to the process of cohesion establishment is unknown. Here, we provide evidence that fission yeast cohesin also displays dynamic behavior. Cohesin association with G1 chromosomes requires continued activity of the cohesin loader Mis4/Ssl3, suggesting that repeated loading cycles maintain cohesin binding. Cohesin instability in G1 depends on wpl1, the fission yeast ortholog of mammalian Wapl, suggestive of a conserved mechanism that controls cohesin stability on chromosomes. wpl1 is nonessential, indicating that a change in wpl1-dependent cohesin dynamics is dispensable for cohesion establishment. Instead, we find that cohesin stability increases at the time of S-phase in a reaction that can be uncoupled from DNA replication. Hence, cohesin stabilization might be a pre-requisite for cohesion establishment rather than its consequence.
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Affiliation(s)
- Pascal Bernard
- Université Bordeaux 2, CNRS Institut de Biochimie et Génétique Cellulaires, Bordeaux, France
| | | | - Sabine Vaur
- Université Bordeaux 2, CNRS Institut de Biochimie et Génétique Cellulaires, Bordeaux, France
| | - Sonia Dheur
- Université Bordeaux 2, CNRS Institut de Biochimie et Génétique Cellulaires, Bordeaux, France
| | - Julie Drogat
- Université Bordeaux 2, CNRS Institut de Biochimie et Génétique Cellulaires, Bordeaux, France
| | - Sylvie Genier
- Université Bordeaux 2, CNRS Institut de Biochimie et Génétique Cellulaires, Bordeaux, France
| | - Karl Ekwall
- Department of Biosciences and Medical Nutrition, School of Life Sciences, Karolinska Institutet, University College Sodertorn, Huddinge, Sweden
| | - Frank Uhlmann
- Chromosome Segregation Laboratory, Cancer Research UK, London Research Institute, London, UK
| | - Jean-Paul Javerzat
- Université Bordeaux 2, CNRS Institut de Biochimie et Génétique Cellulaires, Bordeaux, France
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