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Lu T, Yang J, Cai Y, Ding M, Yu Z, Fang X, Zhou X, Wang X. NCAPD3 promotes diffuse large B-cell lymphoma progression through modulating SIRT1 expression in an H3K9 monomethylation-dependent manner. J Adv Res 2024:S2090-1232(24)00086-9. [PMID: 38432395 DOI: 10.1016/j.jare.2024.02.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 01/31/2024] [Accepted: 02/29/2024] [Indexed: 03/05/2024] Open
Abstract
INTRODUCTION Condensin, a family of structural maintenance of chromosome complexes, has been shown to regulate chromosome compaction and segregation during mitosis. NCAPD3, a HEAT-repeat subunit of condensin II, plays a dominant role in condensin-mediated chromosome dynamics but remains unexplored in lymphoma. OBJECTIVES The study aims to unravel the molecular function and mechanism of NCAPD3 in diffuse large B-cell lymphoma (DLBCL). METHODS The expression and clinical significance of NCAPD3 were assessed in public database and clinical specimens. Chromosome spreads, co-immunoprecipitation (co-IP), mass spectrometry (MS), and chromatin immunoprecipitation (ChIP) assays were conducted to untangle the role and mechanism of NCAPD3 in DLBCL. RESULTS NCAPD3 was highly expressed in DLBCL, correlated with poor prognosis. NCAPD3 deficiency impeded cell proliferation, induced apoptosis and increased the chemosensitivity. Instead, NCAPD3 overexpression facilitated cell proliferation. In vivo experiments further indicated targeting NCAPD3 suppressed tumor growth. Noteworthily, NCAPD3 deficiency disturbed the mitosis, triggering the formation of aneuploids. To reveal the function of NCAPD3 in DLBCL, chromosome spreads were conducted, presenting that chromosomes became compact upon NCAPD3 overexpression, instead, loose, twisted and lacking axial rigidity upon NCAPD3 absence. Meanwhile, the classical transcription-activated marker, H3K4 trimethylation, was found globally upregulated after NCAPD3 knockout, suggesting that NCAPD3 might participate in chromatin remodeling and transcription regulation. MS revealed NCAPD3 could interact with transcription factor, TFII I. Further co-IP and ChIP assays verified NCAPD3 could be anchored at the promoter of SIRT1 by TFII I and then supported the transcription of SIRT1 via recognizing H3K9 monomethylation (H3K9me1) on SIRT1 promoter. Function reversion assay verified the oncogenic role of NCAPD3 in DLBCL was partially mediated by SIRT1. CONCLUSION This study demonstrated that dysregulation of NCAPD3 could disturb chromosome compaction and segregation and regulate the transcription activity of SIRT1 in an H3K9me1-dependent manner, which provided novel insights into targeted strategy for DLBCL.
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Affiliation(s)
- Tiange Lu
- Department of Hematology, Shandong Provincial Hospital, Shandong University, Jinan, Shandong 250021, China
| | - Juan Yang
- Department of Hematology, Shandong Provincial Hospital, Shandong University, Jinan, Shandong 250021, China; National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China
| | - Yiqing Cai
- Department of Hematology, Shandong Provincial Hospital, Shandong University, Jinan, Shandong 250021, China
| | - Mengfei Ding
- Department of Hematology, Shandong Provincial Hospital, Shandong University, Jinan, Shandong 250021, China
| | - Zhuoya Yu
- Department of Hematology, Shandong Provincial Hospital, Shandong University, Jinan, Shandong 250021, China
| | - Xiaosheng Fang
- Department of Hematology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong 250021, China; Taishan Scholars Program of Shandong Province, Jinan, Shandong 250021, China; Branch of National Clinical Research Center for Hematologic Diseases, Jinan, Shandong 250021, China; National Clinical Research Center for Hematologic Diseases, the First Affiliated Hospital of Soochow University, Suzhou 251006, China.
| | - Xiangxiang Zhou
- Department of Hematology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong 250021, China; Taishan Scholars Program of Shandong Province, Jinan, Shandong 250021, China; Branch of National Clinical Research Center for Hematologic Diseases, Jinan, Shandong 250021, China; National Clinical Research Center for Hematologic Diseases, the First Affiliated Hospital of Soochow University, Suzhou 251006, China.
| | - Xin Wang
- Department of Hematology, Shandong Provincial Hospital, Shandong University, Jinan, Shandong 250021, China; Department of Hematology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong 250021, China; Taishan Scholars Program of Shandong Province, Jinan, Shandong 250021, China; Branch of National Clinical Research Center for Hematologic Diseases, Jinan, Shandong 250021, China; National Clinical Research Center for Hematologic Diseases, the First Affiliated Hospital of Soochow University, Suzhou 251006, China.
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Abstract
Many cellular processes require large-scale rearrangements of chromatin structure. Structural maintenance of chromosomes (SMC) protein complexes are molecular machines that can provide structure to chromatin. These complexes can connect DNA elements in cis, walk along DNA, build and processively enlarge DNA loops and connect DNA molecules in trans to hold together the sister chromatids. These DNA-shaping abilities place SMC complexes at the heart of many DNA-based processes, including chromosome segregation in mitosis, transcription control and DNA replication, repair and recombination. In this Review, we discuss the latest insights into how SMC complexes such as cohesin, condensin and the SMC5-SMC6 complex shape DNA to direct these fundamental chromosomal processes. We also consider how SMC complexes, by building chromatin loops, can counteract the natural tendency of alike chromatin regions to cluster. SMC complexes thus control nuclear organization by participating in a molecular tug of war that determines the architecture of our genome.
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Affiliation(s)
- Claire Hoencamp
- Division of Cell Biology, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Benjamin D Rowland
- Division of Cell Biology, The Netherlands Cancer Institute, Amsterdam, The Netherlands.
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Sundararajan S, Park H, Kawano S, Johansson M, Lama B, Saito-Fujita T, Saitoh N, Arnaoutov A, Dasso M, Wang Z, Keifenheim D, Clarke DJ, Azuma Y. Methylated histones on mitotic chromosomes promote topoisomerase IIα function for high fidelity chromosome segregation. iScience 2023; 26:106743. [PMID: 37197327 PMCID: PMC10183659 DOI: 10.1016/j.isci.2023.106743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 10/31/2022] [Accepted: 04/21/2023] [Indexed: 05/19/2023] Open
Abstract
DNA Topoisomerase IIα (TopoIIα) decatenates sister chromatids, allowing their segregation in mitosis. Without the TopoIIα Strand Passage Reaction (SPR), chromosome bridges and ultra-fine DNA bridges (UFBs) arise in anaphase. The TopoIIα C-terminal domain is dispensable for the SPR in vitro but essential for mitotic functions in vivo. Here, we present evidence that the Chromatin Tether (ChT) within the CTD interacts with specific methylated nucleosomes and is crucial for high-fidelity chromosome segregation. Mutation of individual αChT residues disrupts αChT-nucleosome interaction, induces loss of segregation fidelity and reduces association of TopoIIα with chromosomes. Specific methyltransferase inhibitors reducing histone H3 or H4 methylation decreased TopoIIα at centromeres and increased segregation errors. Methyltransferase inhibition did not further increase aberrant anaphases in the ChT mutants, indicating a functional connection. The evidence reveals novel cellular regulation whereby TopoIIα specifically interacts with methylated nucleosomes via the αChT to ensure high-fidelity chromosome segregation.
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Affiliation(s)
- Sanjana Sundararajan
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66045, USA
| | - Hyewon Park
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66045, USA
| | - Shinji Kawano
- Department of Biochemistry, Faculty of Science, Okayama University of Science, Okayama 700-0081, Japan
| | - Marnie Johansson
- Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, MN 55455, USA
| | - Bunu Lama
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66045, USA
| | - Tomoko Saito-Fujita
- Division of Cancer Biology, The Cancer Institute of Japanese Foundation for Cancer Research, Tokyo 135-8550, Japan
| | - Noriko Saitoh
- Division of Cancer Biology, The Cancer Institute of Japanese Foundation for Cancer Research, Tokyo 135-8550, Japan
| | - Alexei Arnaoutov
- Division of Molecular and Cellular Biology, National Institute for Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892-4480, USA
| | - Mary Dasso
- Division of Molecular and Cellular Biology, National Institute for Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892-4480, USA
| | - Zhengqiang Wang
- Center for Drug Design, College of Pharmacy, University of Minnesota, Minneapolis, MN 55455, USA
| | - Daniel Keifenheim
- Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, MN 55455, USA
| | - Duncan J. Clarke
- Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, MN 55455, USA
| | - Yoshiaki Azuma
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66045, USA
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Yoshida MM, Kinoshita K, Aizawa Y, Tane S, Yamashita D, Shintomi K, Hirano T. Molecular dissection of condensin II-mediated chromosome assembly using in vitro assays. eLife 2022; 11:78984. [PMID: 35983835 PMCID: PMC9433093 DOI: 10.7554/elife.78984] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2022] [Accepted: 08/11/2022] [Indexed: 11/18/2022] Open
Abstract
In vertebrates, condensin I and condensin II cooperate to assemble rod-shaped chromosomes during mitosis. Although the mechanism of action and regulation of condensin I have been studied extensively, our corresponding knowledge of condensin II remains very limited. By introducing recombinant condensin II complexes into Xenopus egg extracts, we dissect the roles of its individual subunits in chromosome assembly. We find that one of two HEAT subunits, CAP-D3, plays a crucial role in condensin II-mediated assembly of chromosome axes, whereas the other HEAT subunit, CAP-G2, has a very strong negative impact on this process. The structural maintenance of chromosomes ATPase and the basic amino acid clusters of the kleisin subunit CAP-H2 are essential for this process. Deletion of the C-terminal tail of CAP-D3 increases the ability of condensin II to assemble chromosomes and further exposes a hidden function of CAP-G2 in the lateral compaction of chromosomes. Taken together, our results uncover a multilayered regulatory mechanism unique to condensin II, and provide profound implications for the evolution of condensin II.
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Affiliation(s)
| | | | - Yuuki Aizawa
- Chromosome Dynamics Laboratory, RIKEN, Wako, Japan
| | - Shoji Tane
- Chromosome Dynamics Laboratory, RIKEN, Wako, Japan
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Pommier Y, Nussenzweig A, Takeda S, Austin C. Human topoisomerases and their roles in genome stability and organization. Nat Rev Mol Cell Biol 2022; 23:407-427. [PMID: 35228717 PMCID: PMC8883456 DOI: 10.1038/s41580-022-00452-3] [Citation(s) in RCA: 114] [Impact Index Per Article: 57.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/06/2022] [Indexed: 12/15/2022]
Abstract
Human topoisomerases comprise a family of six enzymes: two type IB (TOP1 and mitochondrial TOP1 (TOP1MT), two type IIA (TOP2A and TOP2B) and two type IA (TOP3A and TOP3B) topoisomerases. In this Review, we discuss their biochemistry and their roles in transcription, DNA replication and chromatin remodelling, and highlight the recent progress made in understanding TOP3A and TOP3B. Because of recent advances in elucidating the high-order organization of the genome through chromatin loops and topologically associating domains (TADs), we integrate the functions of topoisomerases with genome organization. We also discuss the physiological and pathological formation of irreversible topoisomerase cleavage complexes (TOPccs) as they generate topoisomerase DNA–protein crosslinks (TOP-DPCs) coupled with DNA breaks. We discuss the expanding number of redundant pathways that repair TOP-DPCs, and the defects in those pathways, which are increasingly recognized as source of genomic damage leading to neurological diseases and cancer. Topoisomerases have essential roles in transcription, DNA replication, chromatin remodelling and, as recently revealed, 3D genome organization. However, topoisomerases also generate DNA–protein crosslinks coupled with DNA breaks, which are increasingly recognized as a source of disease-causing genomic damage.
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6
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Wenda JM, Prosée RF, Gabus C, Steiner FA. Mitotic chromosome condensation requires phosphorylation of the centromeric protein KNL-2 in C. elegans. J Cell Sci 2021; 134:272713. [PMID: 34734636 PMCID: PMC8714079 DOI: 10.1242/jcs.259088] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 10/25/2021] [Indexed: 11/20/2022] Open
Abstract
Centromeres are chromosomal regions that serve as sites for kinetochore formation and microtubule attachment, processes that are essential for chromosome segregation during mitosis. Centromeres are almost universally defined by the histone variant CENP-A. In the holocentric nematode C. elegans, CENP-A deposition depends on the loading factor KNL-2. Depletion of either CENP-A or KNL-2 results in defects in centromere maintenance, chromosome condensation and kinetochore formation, leading to chromosome segregation failure. Here, we show that KNL-2 is phosphorylated by CDK-1 in vitro, and that mutation of three C-terminal phosphorylation sites causes chromosome segregation defects and an increase in embryonic lethality. In strains expressing phosphodeficient KNL-2, CENP-A and kinetochore proteins are properly localised, indicating that the role of KNL-2 in centromere maintenance is not affected. Instead, the mutant embryos exhibit reduced mitotic levels of condensin II on chromosomes and significant chromosome condensation impairment. Our findings separate the functions of KNL-2 in CENP-A loading and chromosome condensation, and demonstrate that KNL-2 phosphorylation regulates the cooperation between centromeric regions and the condensation machinery in C. elegans. This article has an associated First Person interview with the first author of the paper. Summary: Phosphorylation of the essential centromere protein KNL-2 is required for mitotic chromosome condensation, but not for the role of KNL-2 in centromere maintenance and kinetochore formation.
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Affiliation(s)
- Joanna M Wenda
- Department of Molecular Biology and Institute for Genetics and Genomics in Geneva, Section of Biology, Faculty of Sciences, University of Geneva, 1211 Geneva, Switzerland
| | - Reinier F Prosée
- Department of Molecular Biology and Institute for Genetics and Genomics in Geneva, Section of Biology, Faculty of Sciences, University of Geneva, 1211 Geneva, Switzerland
| | - Caroline Gabus
- Department of Molecular Biology and Institute for Genetics and Genomics in Geneva, Section of Biology, Faculty of Sciences, University of Geneva, 1211 Geneva, Switzerland
| | - Florian A Steiner
- Department of Molecular Biology and Institute for Genetics and Genomics in Geneva, Section of Biology, Faculty of Sciences, University of Geneva, 1211 Geneva, Switzerland
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7
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Vernizzi L, Lehner CF. Bivalent individualization during chromosome territory formation in Drosophila spermatocytes by controlled condensin II protein activity and additional force generators. PLoS Genet 2021; 17:e1009870. [PMID: 34669718 PMCID: PMC8559962 DOI: 10.1371/journal.pgen.1009870] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 11/01/2021] [Accepted: 10/11/2021] [Indexed: 12/12/2022] Open
Abstract
Reduction of genome ploidy from diploid to haploid necessitates stable pairing of homologous chromosomes into bivalents before the start of the first meiotic division. Importantly, this chromosome pairing must avoid interlocking of non-homologous chromosomes. In spermatocytes of Drosophila melanogaster, where homolog pairing does not involve synaptonemal complex formation and crossovers, associations between non-homologous chromosomes are broken up by chromosome territory formation in early spermatocytes. Extensive non-homologous associations arise from the coalescence of the large blocks of pericentromeric heterochromatin into a chromocenter and from centromere clustering. Nevertheless, during territory formation, bivalents are moved apart into spatially separate subnuclear regions. The condensin II subunits, Cap-D3 and Cap-H2, have been implicated, but the remarkable separation of bivalents during interphase might require more than just condensin II. For further characterization of this process, we have applied time-lapse imaging using fluorescent markers of centromeres, telomeres and DNA satellites in pericentromeric heterochromatin. We describe the dynamics of the disruption of centromere clusters and the chromocenter in normal spermatocytes. Mutations in Cap-D3 and Cap-H2 abolish chromocenter disruption, resulting in excessive chromosome missegregation during M I. Chromocenter persistence in the mutants is not mediated by the special system, which conjoins homologs in compensation for the absence of crossovers in Drosophila spermatocytes. However, overexpression of Cap-H2 precluded conjunction between autosomal homologs, resulting in random segregation of univalents. Interestingly, Cap-D3 and Cap-H2 mutant spermatocytes displayed conspicuous stretching of the chromocenter, as well as occasional chromocenter disruption, suggesting that territory formation might involve forces unrelated to condensin II. While the molecular basis of these forces remains to be clarified, they are not destroyed by inhibitors of F actin and microtubules. Our results indicate that condensin II activity promotes chromosome territory formation in co-operation with additional force generators and that careful co-ordination with alternative homolog conjunction is crucial.
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Affiliation(s)
- Luisa Vernizzi
- Department of Molecular Life Science (DMLS), University of Zurich, Zurich, Switzerland
| | - Christian F. Lehner
- Department of Molecular Life Science (DMLS), University of Zurich, Zurich, Switzerland
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8
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Shintomi K, Hirano T. Guiding functions of the C-terminal domain of topoisomerase IIα advance mitotic chromosome assembly. Nat Commun 2021; 12:2917. [PMID: 34006877 PMCID: PMC8131626 DOI: 10.1038/s41467-021-23205-w] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Accepted: 04/20/2021] [Indexed: 12/21/2022] Open
Abstract
Topoisomerase II (topo II) is one of the six proteins essential for mitotic chromatid reconstitution in vitro. It is not fully understood, however, mechanistically how this enzyme regulates this process. In an attempt to further refine the reconstitution assay, we have found that chromosomal binding of Xenopus laevis topo IIα is sensitive to buffer conditions and depends on its C-terminal domain (CTD). Enzymological assays using circular DNA substrates supports the idea that topo IIα first resolves inter-chromatid entanglements to drive individualization and then generates intra-chromatid entanglements to promote thickening. Importantly, only the latter process requires the CTD. By using frog egg extracts, we also show that the CTD contributes to proper formation of nucleosome-depleted chromatids by competing with a linker histone for non-nucleosomal DNA. Our results demonstrate that topo IIα utilizes its CTD to deliver the enzymatic core to crowded environments created during mitotic chromatid assembly, thereby fine-tuning this process. Topoisomerase IIα (topo IIα) is critical for mitotic chromatid assembly. Here the authors report a refinement of the mitotic chromatid reconstitution assay and provide novel insights into the C-terminal domain (CTD) of topo IIα.
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Affiliation(s)
| | - Tatsuya Hirano
- Chromosome Dynamics Laboratory, RIKEN, Wako, Saitama, Japan.
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9
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Paulson JR, Hudson DF, Cisneros-Soberanis F, Earnshaw WC. Mitotic chromosomes. Semin Cell Dev Biol 2021; 117:7-29. [PMID: 33836947 PMCID: PMC8406421 DOI: 10.1016/j.semcdb.2021.03.014] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Revised: 03/23/2021] [Accepted: 03/23/2021] [Indexed: 01/25/2023]
Abstract
Our understanding of the structure and function of mitotic chromosomes has come a long way since these iconic objects were first recognized more than 140 years ago, though many details remain to be elucidated. In this chapter, we start with the early history of chromosome studies and then describe the path that led to our current understanding of the formation and structure of mitotic chromosomes. We also discuss some of the remaining questions. It is now well established that each mitotic chromatid consists of a central organizing region containing a so-called "chromosome scaffold" from which loops of DNA project radially. Only a few key non-histone proteins and protein complexes are required to form the chromosome: topoisomerase IIα, cohesin, condensin I and condensin II, and the chromokinesin KIF4A. These proteins are concentrated along the axis of the chromatid. Condensins I and II are primarily responsible for shaping the chromosome and the scaffold, and they produce the loops of DNA by an ATP-dependent process known as loop extrusion. Modelling of Hi-C data suggests that condensin II adopts a spiral staircase arrangement with an extruded loop extending out from each step in a roughly helical pattern. Condensin I then forms loops nested within these larger condensin II loops, thereby giving rise to the final compaction of the mitotic chromosome in a process that requires Topo IIα.
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Affiliation(s)
- James R Paulson
- Department of Chemistry, University of Wisconsin Oshkosh, 800 Algoma Boulevard, Oshkosh, WI 54901, USA.
| | - Damien F Hudson
- Murdoch Children's Research Institute, Royal Children's Hospital, Parkville, VIC 3052, Australia
| | - Fernanda Cisneros-Soberanis
- Wellcome Trust Centre for Cell Biology, ICB, University of Edinburgh, Michael Swann Building, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, Scotland, UK
| | - William C Earnshaw
- Wellcome Trust Centre for Cell Biology, ICB, University of Edinburgh, Michael Swann Building, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, Scotland, UK.
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10
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Wang H, Liu X, Li G. Explore a novel function of human condensins in cellular senescence. Cell Biosci 2020; 10:147. [PMID: 33375949 PMCID: PMC7772929 DOI: 10.1186/s13578-020-00512-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2020] [Accepted: 12/06/2020] [Indexed: 11/26/2022] Open
Abstract
There are two kinds of condensins in human cells, known as condensin I and condensin II. The canonical roles of condensins are participated in chromosome dynamics, including chromosome condensation and segregation during cell division. Recently, a novel function of human condensins has been found with increasing evidences that they play important roles in cellular senescence. This paper reviewed the research progress of human condensins involved in different types of cellular senescence, mainly oncogene-induced senescence (OIS) and replicative senescence (RS). The future perspectives of human condensins involved in cellular senescence are also discussed.
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Affiliation(s)
- Hongzhen Wang
- School of Life Sciences, Jilin Normal University, 136000, Siping, People's Republic of China. .,Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education, School of Life Sciences, Jilin University, 130012, Changchun, People's Republic of China.
| | - Xin Liu
- School of Life Sciences, Jilin Normal University, 136000, Siping, People's Republic of China
| | - Guiying Li
- Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education, School of Life Sciences, Jilin University, 130012, Changchun, People's Republic of China
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11
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Banigan EJ, Mirny LA. The interplay between asymmetric and symmetric DNA loop extrusion. eLife 2020; 9:e63528. [PMID: 33295869 PMCID: PMC7793625 DOI: 10.7554/elife.63528] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Accepted: 11/30/2020] [Indexed: 12/30/2022] Open
Abstract
Chromosome compaction is essential for reliable transmission of genetic information. Experiments suggest that ∼1000-fold compaction is driven by condensin complexes that extrude chromatin loops, by progressively collecting chromatin fiber from one or both sides of the complex to form a growing loop. Theory indicates that symmetric two-sided loop extrusion can achieve such compaction, but recent single-molecule studies (Golfier et al., 2020) observed diverse dynamics of condensins that perform one-sided, symmetric two-sided, and asymmetric two-sided extrusion. We use simulations and theory to determine how these molecular properties lead to chromosome compaction. High compaction can be achieved if even a small fraction of condensins have two essential properties: a long residence time and the ability to perform two-sided (not necessarily symmetric) extrusion. In mixtures of condensins I and II, coupling two-sided extrusion and stable chromatin binding by condensin II promotes compaction. These results provide missing connections between single-molecule observations and chromosome-scale organization.
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Affiliation(s)
- Edward J Banigan
- Department of Physics and Institute for Medical Engineering and Science, Massachusetts Institute of TechnologyCambridgeUnited States
| | - Leonid A Mirny
- Department of Physics and Institute for Medical Engineering and Science, Massachusetts Institute of TechnologyCambridgeUnited States
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12
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Cutts EE, Vannini A. Condensin complexes: understanding loop extrusion one conformational change at a time. Biochem Soc Trans 2020; 48:2089-2100. [PMID: 33005926 PMCID: PMC7609036 DOI: 10.1042/bst20200241] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 09/07/2020] [Accepted: 09/09/2020] [Indexed: 12/12/2022]
Abstract
Condensin and cohesin, both members of the structural maintenance of chromosome (SMC) family, contribute to the regulation and structure of chromatin. Recent work has shown both condensin and cohesin extrude DNA loops and most likely work via a conserved mechanism. This review focuses on condensin complexes, highlighting recent in vitro work characterising DNA loop formation and protein structure. We discuss similarities between condensin and cohesin complexes to derive a possible mechanistic model, as well as discuss differences that exist between the different condensin isoforms found in higher eukaryotes.
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Affiliation(s)
- Erin E. Cutts
- Division of Structural Biology, The Institute of Cancer Research, London SW7 3RP, U.K
| | - Alessandro Vannini
- Division of Structural Biology, The Institute of Cancer Research, London SW7 3RP, U.K
- Fondazione Human Technopole, Structural Biology Research Centre, 20157 Milan, Italy
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13
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Kleinschnitz K, Vießmann N, Jordan M, Heidmann SK. Condensin I is required for faithful meiosis in Drosophila males. Chromosoma 2020; 129:141-160. [PMID: 32314039 PMCID: PMC7260282 DOI: 10.1007/s00412-020-00733-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Revised: 02/17/2020] [Accepted: 02/20/2020] [Indexed: 01/03/2023]
Abstract
The heteropentameric condensin complexes play vital roles in the formation and faithful segregation of mitotic chromosomes in eukaryotes. While the different contributions of the two common condensin complexes, condensin I and condensin II, to chromosome morphology and behavior in mitosis have been thoroughly investigated, much less is known about the specific roles of the two complexes during meiotic divisions. In Drosophila melanogaster, faithful mitotic divisions depend on functional condensin I, but not on condensin II. However, meiotic divisions in Drosophila males require functional condensin II subunits. The role of condensin I during male meiosis in Drosophila has been unresolved. Here, we show that condensin I-specific subunits localize to meiotic chromatin in both meiosis I and II during Drosophila spermatogenesis. Live cell imaging reveals defects during meiotic divisions after RNAi-mediated knockdown of condensin I-specific mRNAs. This phenotype correlates with reduced male fertility and an increase in nondisjunction events both in meiosis I and meiosis II. Consistently, a reduction in male fertility was also observed after proteasome-mediated degradation of the condensin I subunit Barren. Taken together, our results demonstrate an essential role of condensin I during male meiosis in Drosophila melanogaster.
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Affiliation(s)
| | - Nina Vießmann
- Lehrstuhl für Genetik, University of Bayreuth, Bayreuth, Germany
| | - Mareike Jordan
- Lehrstuhl für Genetik, University of Bayreuth, Bayreuth, Germany
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
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14
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Yasuda Y, Tokunaga K, Koga T, Sakamoto C, Goldberg IG, Saitoh N, Nakao M. Computational analysis of morphological and molecular features in gastric cancer tissues. Cancer Med 2020; 9:2223-2234. [PMID: 32012497 PMCID: PMC7064096 DOI: 10.1002/cam4.2885] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 11/13/2019] [Accepted: 01/14/2020] [Indexed: 02/06/2023] Open
Abstract
Biological morphologies of cells and tissues represent their physiological and pathological conditions. The importance of quantitative assessment of morphological information has been highly recognized in clinical diagnosis and therapeutic strategies. In this study, we used a supervised machine learning algorithm wndchrm to classify hematoxylin and eosin (H&E)‐stained images of human gastric cancer tissues. This analysis distinguished between noncancer and cancer tissues with different histological grades. We then classified the H&E‐stained images by expression levels of cancer‐associated nuclear ATF7IP/MCAF1 and membranous PD‐L1 proteins using immunohistochemistry of serial sections. Interestingly, classes with low and high expressions of each protein exhibited significant morphological dissimilarity in H&E images. These results indicated that morphological features in cancer tissues are correlated with expression of specific cancer‐associated proteins, suggesting the usefulness of biomolecular‐based morphological classification.
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Affiliation(s)
- Yoko Yasuda
- Department of Medical Cell Biology, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto, Japan.,Department of Health Science, Faculty of Medical Science, Kyushu University, Fukuoka, Japan
| | - Kazuaki Tokunaga
- Department of Medical Cell Biology, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto, Japan
| | - Tomoaki Koga
- Department of Medical Cell Biology, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto, Japan
| | - Chiyomi Sakamoto
- Department of Medical Cell Biology, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto, Japan
| | - Ilya G Goldberg
- Image Informatics and Computational Biology Unit, Laboratory of Genetics, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA
| | | | - Mitsuyoshi Nakao
- Department of Medical Cell Biology, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto, Japan
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15
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Chromosome disentanglement driven via optimal compaction of loop-extruded brush structures. Proc Natl Acad Sci U S A 2019; 116:24956-24965. [PMID: 31757850 DOI: 10.1073/pnas.1906355116] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Eukaryote cell division features a chromosome compaction-decompaction cycle that is synchronized with their physical and topological segregation. It has been proposed that lengthwise compaction of chromatin into mitotic chromosomes via loop extrusion underlies the compaction-segregation/resolution process. We analyze this disentanglement scheme via considering the chromosome to be a succession of DNA/chromatin loops-a polymer "brush"-where active extrusion of loops controls the brush structure. Given type-II DNA topoisomerase (Topo II)-catalyzed topology fluctuations, we find that interchromosome entanglements are minimized for a certain "optimal" loop that scales with the chromosome size. The optimal loop organization is in accord with experimental data across species, suggesting an important structural role of genomic loops in maintaining a less entangled genome. Application of the model to the interphase genome indicates that active loop extrusion can maintain a level of chromosome compaction with suppressed entanglements; the transition to the metaphase state requires higher lengthwise compaction and drives complete topological segregation. Optimized genomic loops may provide a means for evolutionary propagation of gene-expression patterns while simultaneously maintaining a disentangled genome. We also find that compact metaphase chromosomes have a densely packed core along their cylindrical axes that explains their observed mechanical stiffness. Our model connects chromosome structural reorganization to topological resolution through the cell cycle and highlights a mechanism of directing Topo II-mediated strand passage via loop extrusion-driven lengthwise compaction.
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16
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Sun C, Huang S, Wang H, Xie R, Zhang L, Zhou Q, He X, Ju W. Non-SMC condensin I complex subunit H enhances proliferation, migration, and invasion of hepatocellular carcinoma. Mol Carcinog 2019; 58:2266-2275. [PMID: 31523845 PMCID: PMC6899668 DOI: 10.1002/mc.23114] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 08/26/2019] [Accepted: 08/30/2019] [Indexed: 12/16/2022]
Abstract
Non‐SMC condensing I complex subunit H (NCAPH) is a member of the Barr protein family and part of the condensin I complex. The upregulation of NCAPH is associated with poor prognosis in patients with colon cancer. However, the relationship between NCAPH and hepatocellular carcinoma (HCC) remains unclear. This study aimed to explore NCAPH expression in HCC tissues and to investigate NCAPH functions in HCC cells. In this study, we found that high expression of NCAPH in HCC indicated worse prognosis via bioinformatics analysis. Consistently, quantitative real‐time polymerase chain reaction assays in 20 pairs of HCC specimens and the immunohistochemical analysis of 100 HCC tissues showed the upregulation of NCAPH. We established stable NCAPH‐overexpressing and NCAPH knockdown cell lines. Cell Counting Kit‐8 assays and colony formation assay were performed to analyze cell proliferation. Migration and invasion were analyzed by Transwell assays. Subcutaneous xenograft models were used to explore the role of NCAPH in tumor formation in vivo. Our results showed that NCAPH promoted tumor proliferation, migration, and invasion in vitro and in vivo. In conclusion, our findings indicate that NCAPH could serve as a novel prognostic biomarker and a potential therapeutic target for patients with HCC.
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Affiliation(s)
- Chengjun Sun
- Organ Transplant Center, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Shanzhou Huang
- Department of General Surgery, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangdong, China
| | - Hanyu Wang
- Organ Transplant Center, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Rongxing Xie
- Organ Transplant Center, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Lishan Zhang
- Organ Transplant Center, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Qi Zhou
- Department of Liver Surgery, The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China.,Department of General Surgery, Hui Ya Hospital of The First Affiliated Hospital, Sun Yat-sen University, Huizhou, Guangdong, China
| | - Xiaoshun He
- Organ Transplant Center, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Weiqiang Ju
- Organ Transplant Center, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
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17
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Abstract
Condensins and cohesins are highly conserved complexes that tether together DNA loci within a single DNA molecule to produce DNA loops. Condensin and cohesin structures, however, are different, and the DNA loops produced by each underlie distinct cell processes. Condensin rods compact chromosomes during mitosis, with condensin I and II complexes producing spatially defined and nested looping in metazoan cells. Structurally adaptive cohesin rings produce loops, which organize the genome during interphase. Cohesin-mediated loops, termed topologically associating domains or TADs, antagonize the formation of epigenetically defined but untethered DNA volumes, termed compartments. While condensin complexes formed through cis-interactions must maintain chromatin compaction throughout mitosis, cohesins remain highly dynamic during interphase to allow for transcription-mediated responses to external cues and the execution of developmental programs. Here, I review differences in condensin and cohesin structures, and highlight recent advances regarding the intramolecular or cis-based tetherings through which condensins compact DNA during mitosis and cohesins organize the genome during interphase.
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Affiliation(s)
- Robert V Skibbens
- Department of Biological Sciences, 111 Research Drive, Lehigh University, Bethlehem, PA 18015, USA
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18
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Lawrimore J, Doshi A, Friedman B, Yeh E, Bloom K. Geometric partitioning of cohesin and condensin is a consequence of chromatin loops. Mol Biol Cell 2018; 29:2737-2750. [PMID: 30207827 PMCID: PMC6249845 DOI: 10.1091/mbc.e18-02-0131] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 08/13/2018] [Accepted: 09/04/2018] [Indexed: 12/29/2022] Open
Abstract
SMC (structural maintenance of chromosomes) complexes condensin and cohesin are crucial for proper chromosome organization. Condensin has been reported to be a mechanochemical motor capable of forming chromatin loops, while cohesin passively diffuses along chromatin to tether sister chromatids. In budding yeast, the pericentric region is enriched in both condensin and cohesin. As in higher-eukaryotic chromosomes, condensin is localized to the axial chromatin of the pericentric region, while cohesin is enriched in the radial chromatin. Thus, the pericentric region serves as an ideal model for deducing the role of SMC complexes in chromosome organization. We find condensin-mediated chromatin loops establish a robust chromatin organization, while cohesin limits the area that chromatin loops can explore. Upon biorientation, extensional force from the mitotic spindle aggregates condensin-bound chromatin from its equilibrium position to the axial core of pericentric chromatin, resulting in amplified axial tension. The axial localization of condensin depends on condensin's ability to bind to chromatin to form loops, while the radial localization of cohesin depends on cohesin's ability to diffuse along chromatin. The different chromatin-tethering modalities of condensin and cohesin result in their geometric partitioning in the presence of an extensional force on chromatin.
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Affiliation(s)
- Josh Lawrimore
- Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
- Biology Department, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Ayush Doshi
- Biology Department, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Brandon Friedman
- Biology Department, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Elaine Yeh
- Biology Department, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Kerry Bloom
- Biology Department, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
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19
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Condensin controls mitotic chromosome stiffness and stability without forming a structurally contiguous scaffold. Chromosome Res 2018; 26:277-295. [PMID: 30143891 DOI: 10.1007/s10577-018-9584-1] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Revised: 08/03/2018] [Accepted: 08/07/2018] [Indexed: 01/26/2023]
Abstract
During cell division, chromosomes must be folded into their compact mitotic form to ensure their segregation. This process is thought to be largely controlled by the action of condensin SMC protein complexes on chromatin fibers. However, how condensins organize metaphase chromosomes is not understood. We have combined micromanipulation of single human mitotic chromosomes, sub-nanonewton force measurement, siRNA interference of condensin subunit expression, and fluorescence microscopy, to analyze the role of condensin in large-scale chromosome organization. Condensin depletion leads to a dramatic (~ 10-fold) reduction in chromosome elastic stiffness relative to the native, non-depleted case. We also find that prolonged metaphase stalling of cells leads to overloading of chromosomes with condensin, with abnormally high chromosome stiffness. These results demonstrate that condensin is a main element controlling the stiffness of mitotic chromosomes. Isolated, slightly stretched chromosomes display a discontinuous condensing staining pattern, suggesting that condensins organize mitotic chromosomes by forming isolated compaction centers that do not form a continuous scaffold.
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20
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Takagi M, Ono T, Natsume T, Sakamoto C, Nakao M, Saitoh N, Kanemaki MT, Hirano T, Imamoto N. Ki-67 and condensins support the integrity of mitotic chromosomes through distinct mechanisms. J Cell Sci 2018; 131:jcs.212092. [PMID: 29487178 DOI: 10.1242/jcs.212092] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Accepted: 02/15/2018] [Indexed: 12/11/2022] Open
Abstract
Although condensins play essential roles in mitotic chromosome assembly, Ki-67 (also known as MKI67), a protein localizing to the periphery of mitotic chromosomes, had also been shown to make a contribution to the process. To examine their respective roles, we generated a set of HCT116-based cell lines expressing Ki-67 and/or condensin subunits that were fused with an auxin-inducible degron for their conditional degradation. Both the localization and the dynamic behavior of Ki-67 on mitotic chromosomes were not largely affected upon depletion of condensin subunits, and vice versa. When both Ki-67 and SMC2 (a core subunit of condensins) were depleted, ball-like chromosome clusters with no sign of discernible thread-like structures were observed. This severe defective phenotype was distinct from that observed in cells depleted of either Ki-67 or SMC2 alone. Our results show that Ki-67 and condensins, which localize to the external surface and the central axis of mitotic chromosomes, respectively, have independent yet cooperative functions in supporting the structural integrity of mitotic chromosomes.
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Affiliation(s)
| | - Takao Ono
- Chromosome Dynamics Laboratory, RIKEN, Wako 351-0198, Japan
| | - Toyoaki Natsume
- Division of Molecular Cell Engineering, NIG, Mishima 411-8540, Japan
| | - Chiyomi Sakamoto
- Department of Medical Cell Biology, IMEG, Kumamoto University, Kumamoto 860-0811, Japan
| | - Mitsuyoshi Nakao
- Department of Medical Cell Biology, IMEG, Kumamoto University, Kumamoto 860-0811, Japan
| | - Noriko Saitoh
- Department of Medical Cell Biology, IMEG, Kumamoto University, Kumamoto 860-0811, Japan.,Department of Cancer Biology, The Cancer Institute of JFCR, Tokyo 135-8550, Japan
| | - Masato T Kanemaki
- Division of Molecular Cell Engineering, NIG, Mishima 411-8540, Japan
| | - Tatsuya Hirano
- Chromosome Dynamics Laboratory, RIKEN, Wako 351-0198, Japan
| | - Naoko Imamoto
- Cellular Dynamics Laboratory, RIKEN, Wako 351-0198, Japan
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21
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Wang HZ, Yang SH, Li GY, Cao X. Subunits of human condensins are potential therapeutic targets for cancers. Cell Div 2018; 13:2. [PMID: 29467813 PMCID: PMC5819170 DOI: 10.1186/s13008-018-0035-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Accepted: 02/05/2018] [Indexed: 11/16/2022] Open
Abstract
The main role of condensins is to regulate chromosome condensation and segregation during cell cycles. Recently, it has been suggested in the literatures that subunits of condensin I and condensin II are involved in some human cancers. This paper will first briefly discuss discoveries of human condensins, their components and structures, and their multiple cellular functions. This will be followed by reviews of most recent studies on subunits of human condensins and their dysregulations or mutations in human cancers. It can be concluded that many of these subunits have potentials to be novel targets for cancer therapies. However, hCAP-D2, a subunit of human condensin I, has not been directly documented to be associated with any human cancers to date. This review hypothesizes that hCAP-D2 can also be a potential therapeutic target for human cancers, and therefore that all subunits of human condensins are potential therapeutic targets for human cancers.
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Affiliation(s)
- Hong-Zhen Wang
- 1School of Life Sciences, Jilin Normal University, Siping, 136000 P. R. China.,2Key Laboratory for Molecular Enzymology and Engineering of The Ministry of Education, School of Life Sciences, Jilin University, Changchun, 130012 P. R. China.,3Department of Chemical and Biological Engineering, University of Ottawa, Ottawa, K1N 6N5 Canada
| | - Si-Han Yang
- 1School of Life Sciences, Jilin Normal University, Siping, 136000 P. R. China
| | - Gui-Ying Li
- 2Key Laboratory for Molecular Enzymology and Engineering of The Ministry of Education, School of Life Sciences, Jilin University, Changchun, 130012 P. R. China
| | - Xudong Cao
- 3Department of Chemical and Biological Engineering, University of Ottawa, Ottawa, K1N 6N5 Canada
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22
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Shintomi K, Hirano T. Mitotic Chromosome Assembly In Vitro: Functional Cross Talk between Nucleosomes and Condensins. COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY 2017; 82:157-164. [PMID: 29118204 DOI: 10.1101/sqb.2017.82.033639] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The mitotic chromosome is a macromolecular assembly that ensures error-free transmission of the genome during cell division. It has long been a big mystery how long stretches of DNA might be folded into rod-shaped chromosomes or how such an elaborate process might be accomplished at a mechanistic level. Cell-free extracts made from frog eggs offer a unique opportunity to address these questions by enabling mitotic chromosomes to be assembled in a test tube. Moreover, the core part of the chromosome assembly reaction can now be reconstituted with a limited number of purified factors. A combination of these in vitro assays makes it possible not only to prepare a complete list of proteins required for chromosome assembly but also to dissect functions of individual proteins and their cooperation with unparalleled clarity. Emerging lines of evidence underscore the paramount importance of condensins in building mitotic chromosomes and shed new light on the functional cross talk between nucleosomes and condensins in this process.
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Affiliation(s)
- Keishi Shintomi
- Chromosome Dynamics Laboratory, RIKEN, Wako, Saitama 351-0198, Japan
| | - Tatsuya Hirano
- Chromosome Dynamics Laboratory, RIKEN, Wako, Saitama 351-0198, Japan
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