1
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Zagelbaum J, Gautier J. Double-strand break repair and mis-repair in 3D. DNA Repair (Amst) 2023; 121:103430. [PMID: 36436496 PMCID: PMC10799305 DOI: 10.1016/j.dnarep.2022.103430] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 11/13/2022] [Accepted: 11/15/2022] [Indexed: 11/18/2022]
Abstract
DNA double-strand breaks (DSBs) are lesions that arise frequently from exposure to damaging agents as well as from ongoing physiological DNA transactions. Mis-repair of DSBs leads to rearrangements and structural variations in chromosomes, including insertions, deletions, and translocations implicated in disease. The DNA damage response (DDR) limits pathologic mutations and large-scale chromosome rearrangements. DSB repair initiates in 2D at DNA lesions with the stepwise recruitment of repair proteins and local chromatin remodeling which facilitates break accessibility. More complex structures are then formed via protein assembly into nanodomains and via genome folding into chromatin loops. Subsequently, 3D reorganization of DSBs is guided by clustering forces which drive the assembly of repair domains harboring multiple lesions. These domains are further stabilized and insulated into condensates via liquid-liquid phase-separation. Here, we discuss the benefits and risks associated with this 3D reorganization of the broken genome.
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Affiliation(s)
- Jennifer Zagelbaum
- Institute for Cancer Genetics, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA; Integrated Program in Cellular, Molecular, and Biomedical Studies, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
| | - Jean Gautier
- Institute for Cancer Genetics, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA; Department of Genetics and Development, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA.
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2
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Masai H. Replicon hypothesis revisited. Biochem Biophys Res Commun 2022; 633:77-80. [DOI: 10.1016/j.bbrc.2022.09.060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Accepted: 09/14/2022] [Indexed: 11/06/2022]
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3
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Effects of replication domains on genome-wide UV-induced DNA damage and repair. PLoS Genet 2022; 18:e1010426. [PMID: 36155646 PMCID: PMC9536635 DOI: 10.1371/journal.pgen.1010426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Revised: 10/06/2022] [Accepted: 09/12/2022] [Indexed: 11/19/2022] Open
Abstract
Nucleotide excision repair is the primary repair mechanism that removes UV-induced DNA lesions in placentals. Unrepaired UV-induced lesions could result in mutations during DNA replication. Although the mutagenesis of pyrimidine dimers is reasonably well understood, the direct effects of replication fork progression on nucleotide excision repair are yet to be clarified. Here, we applied Damage-seq and XR-seq techniques and generated replication maps in synchronized UV-treated HeLa cells. The results suggest that ongoing replication stimulates local repair in both early and late replication domains. Additionally, it was revealed that lesions on lagging strand templates are repaired slower in late replication domains, which is probably due to the imbalanced sequence context. Asymmetric relative repair is in line with the strand bias of melanoma mutations, suggesting a role of exogenous damage, repair, and replication in mutational strand asymmetry.
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4
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Belmont AS. Nuclear Compartments: An Incomplete Primer to Nuclear Compartments, Bodies, and Genome Organization Relative to Nuclear Architecture. Cold Spring Harb Perspect Biol 2021; 14:cshperspect.a041268. [PMID: 34400557 PMCID: PMC9248822 DOI: 10.1101/cshperspect.a041268] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
This work reviews nuclear compartments, defined broadly to include distinct nuclear structures, bodies, and chromosome domains. It first summarizes original cytological observations before comparing concepts of nuclear compartments emerging from microscopy versus genomic approaches and then introducing new multiplexed imaging approaches that promise in the future to meld both approaches. I discuss how previous models of radial distribution of chromosomes or the binary division of the genome into A and B compartments are now being refined by the recognition of more complex nuclear compartmentalization. The poorly understood question of how these nuclear compartments are established and maintained is then discussed, including through the modern perspective of phase separation, before moving on to address possible functions of nuclear compartments, using the possible role of nuclear speckles in modulating gene expression as an example. Finally, the review concludes with a discussion of future questions for this field.
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Affiliation(s)
- Andrew S Belmont
- Department of Cell and Developmental Biology, University of Illinois, Urbana-Champaign, Urbana, Illinois 61801, USA
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5
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Kirstein N, Buschle A, Wu X, Krebs S, Blum H, Kremmer E, Vorberg IM, Hammerschmidt W, Lacroix L, Hyrien O, Audit B, Schepers A. Human ORC/MCM density is low in active genes and correlates with replication time but does not delimit initiation zones. eLife 2021; 10:62161. [PMID: 33683199 PMCID: PMC7993996 DOI: 10.7554/elife.62161] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Accepted: 03/05/2021] [Indexed: 12/22/2022] Open
Abstract
Eukaryotic DNA replication initiates during S phase from origins that have been licensed in the preceding G1 phase. Here, we compare ChIP-seq profiles of the licensing factors Orc2, Orc3, Mcm3, and Mcm7 with gene expression, replication timing, and fork directionality profiles obtained by RNA-seq, Repli-seq, and OK-seq. Both, the origin recognition complex (ORC) and the minichromosome maintenance complex (MCM) are significantly and homogeneously depleted from transcribed genes, enriched at gene promoters, and more abundant in early- than in late-replicating domains. Surprisingly, after controlling these variables, no difference in ORC/MCM density is detected between initiation zones, termination zones, unidirectionally replicating regions, and randomly replicating regions. Therefore, ORC/MCM density correlates with replication timing but does not solely regulate the probability of replication initiation. Interestingly, H4K20me3, a histone modification proposed to facilitate late origin licensing, was enriched in late-replicating initiation zones and gene deserts of stochastic replication fork direction. We discuss potential mechanisms specifying when and where replication initiates in human cells.
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Affiliation(s)
- Nina Kirstein
- Research Unit Gene Vectors, Helmholtz Zentrum München (GmbH), German Research Center for Environmental Health, Munich, Germany
| | - Alexander Buschle
- Research Unit Gene Vectors, Helmholtz Zentrum München (GmbH), German Research Center for Environmental Health and German Center for Infection Research (DZIF), Munich, Germany
| | - Xia Wu
- Institut de Biologie de l'ENS (IBENS), Département de Biologie, Ecole Normale Supérieure, CNRS, Inserm, PSL Research University, Paris, France
| | - Stefan Krebs
- Laboratory for Functional Genome Analysis (LAFUGA), Gene Center of the Ludwig-Maximilians Universität (LMU) München, Munich, Germany
| | - Helmut Blum
- Laboratory for Functional Genome Analysis (LAFUGA), Gene Center of the Ludwig-Maximilians Universität (LMU) München, Munich, Germany
| | - Elisabeth Kremmer
- Institute for Molecular Immunology, Monoclonal Antibody Core Facility, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Neuherberg, Germany
| | - Ina M Vorberg
- German Center for Neurodegenerative Diseases (DZNE e.V.), Bonn, Germany.,Rheinische Friedrich-Wilhelms-Universität Bonn, Bonn, Germany
| | - Wolfgang Hammerschmidt
- Research Unit Gene Vectors, Helmholtz Zentrum München (GmbH), German Research Center for Environmental Health and German Center for Infection Research (DZIF), Munich, Germany
| | - Laurent Lacroix
- Institut de Biologie de l'ENS (IBENS), Département de Biologie, Ecole Normale Supérieure, CNRS, Inserm, PSL Research University, Paris, France
| | - Olivier Hyrien
- Institut de Biologie de l'ENS (IBENS), Département de Biologie, Ecole Normale Supérieure, CNRS, Inserm, PSL Research University, Paris, France
| | - Benjamin Audit
- Univ Lyon, ENS de Lyon, Univ. Claude Bernard, CNRS, Laboratoire de Physique, 69342 Lyon, France
| | - Aloys Schepers
- Research Unit Gene Vectors, Helmholtz Zentrum München (GmbH), German Research Center for Environmental Health, Munich, Germany
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6
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Dao FY, Lv H, Zhang D, Zhang ZM, Liu L, Lin H. DeepYY1: a deep learning approach to identify YY1-mediated chromatin loops. Brief Bioinform 2020; 22:6024741. [PMID: 33279983 DOI: 10.1093/bib/bbaa356] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 10/19/2020] [Accepted: 11/04/2020] [Indexed: 12/29/2022] Open
Abstract
The protein Yin Yang 1 (YY1) could form dimers that facilitate the interaction between active enhancers and promoter-proximal elements. YY1-mediated enhancer-promoter interaction is the general feature of mammalian gene control. Recently, some computational methods have been developed to characterize the interactions between DNA elements by elucidating important features of chromatin folding; however, no computational methods have been developed for identifying the YY1-mediated chromatin loops. In this study, we developed a deep learning algorithm named DeepYY1 based on word2vec to determine whether a pair of YY1 motifs would form a loop. The proposed models showed a high prediction performance (AUCs$\ge$0.93) on both training datasets and testing datasets in different cell types, demonstrating that DeepYY1 has an excellent performance in the identification of the YY1-mediated chromatin loops. Our study also suggested that sequences play an important role in the formation of YY1-mediated chromatin loops. Furthermore, we briefly discussed the distribution of the replication origin site in the loops. Finally, a user-friendly web server was established, and it can be freely accessed at http://lin-group.cn/server/DeepYY1.
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Affiliation(s)
- Fu-Ying Dao
- Center for Informational Biology at the University of Electronic Science and Technology of China
| | - Hao Lv
- Center for Informational Biology at the University of Electronic Science and Technology of China
| | - Dan Zhang
- Center for Informational Biology at the University of Electronic Science and Technology of China
| | - Zi-Mei Zhang
- Center for Informational Biology at the University of Electronic Science and Technology of China
| | - Li Liu
- Laboratory of Theoretical Biophysics at the Inner Mongolia University
| | - Hao Lin
- Center for Informational Biology at the University of Electronic Science and Technology of China
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7
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Cremer M, Brandstetter K, Maiser A, Rao SSP, Schmid VJ, Guirao-Ortiz M, Mitra N, Mamberti S, Klein KN, Gilbert DM, Leonhardt H, Cardoso MC, Aiden EL, Harz H, Cremer T. Cohesin depleted cells rebuild functional nuclear compartments after endomitosis. Nat Commun 2020; 11:6146. [PMID: 33262376 PMCID: PMC7708632 DOI: 10.1038/s41467-020-19876-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 10/28/2020] [Indexed: 01/05/2023] Open
Abstract
Cohesin plays an essential role in chromatin loop extrusion, but its impact on a compartmentalized nuclear architecture, linked to nuclear functions, is less well understood. Using live-cell and super-resolved 3D microscopy, here we find that cohesin depletion in a human colon cancer derived cell line results in endomitosis and a single multilobulated nucleus with chromosome territories pervaded by interchromatin channels. Chromosome territories contain chromatin domain clusters with a zonal organization of repressed chromatin domains in the interior and transcriptionally competent domains located at the periphery. These clusters form microscopically defined, active and inactive compartments, which likely correspond to A/B compartments, which are detected with ensemble Hi-C. Splicing speckles are observed nearby within the lining channel system. We further observe that the multilobulated nuclei, despite continuous absence of cohesin, pass through S-phase with typical spatio-temporal patterns of replication domains. Evidence for structural changes of these domains compared to controls suggests that cohesin is required for their full integrity.
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Affiliation(s)
- Marion Cremer
- Anthropology and Human Genomics, Department Biology II, Ludwig-Maximilians-Universität München, München, Germany.
| | - Katharina Brandstetter
- Human Biology & BioImaging, Center for Molecular Biosystems, Department Biology II, Ludwig-Maximilians-Universität München, München, Germany
| | - Andreas Maiser
- Human Biology & BioImaging, Center for Molecular Biosystems, Department Biology II, Ludwig-Maximilians-Universität München, München, Germany
| | - Suhas S P Rao
- Center for Genome Architecture, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
- Department of Structural Biology, Stanford University School of Medicine, California, USA
| | - Volker J Schmid
- Bayesian Imaging and Spatial Statistics Group, Department of Statistics, Ludwig-Maximilians-Universität München, München, Germany
| | - Miguel Guirao-Ortiz
- Human Biology & BioImaging, Center for Molecular Biosystems, Department Biology II, Ludwig-Maximilians-Universität München, München, Germany
| | - Namita Mitra
- Center for Genome Architecture, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Stefania Mamberti
- Cell Biology and Epigenetics, Department of Biology, Technische Universität Darmstadt, Darmstadt, Germany
| | - Kyle N Klein
- Department of Biological Science, Florida State University, Tallahassee, FL, USA
| | - David M Gilbert
- Department of Biological Science, Florida State University, Tallahassee, FL, USA
| | - Heinrich Leonhardt
- Human Biology & BioImaging, Center for Molecular Biosystems, Department Biology II, Ludwig-Maximilians-Universität München, München, Germany
| | - M Cristina Cardoso
- Cell Biology and Epigenetics, Department of Biology, Technische Universität Darmstadt, Darmstadt, Germany
| | - Erez Lieberman Aiden
- Center for Genome Architecture, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
- Center for Theoretical Biological Physics, Rice University, Houston, TX, USA
- Broad Institute of the Massachusetts Institute of Technology and Harvard University, Cambridge, MA, USA
- Departments of Computer Science and Computational and Applied Mathematics, Rice University, Houston, TX, USA
| | - Hartmann Harz
- Human Biology & BioImaging, Center for Molecular Biosystems, Department Biology II, Ludwig-Maximilians-Universität München, München, Germany.
| | - Thomas Cremer
- Anthropology and Human Genomics, Department Biology II, Ludwig-Maximilians-Universität München, München, Germany.
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8
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Abstract
In all kingdoms of life, DNA is used to encode hereditary information. Propagation of the genetic material between generations requires timely and accurate duplication of DNA by semiconservative replication prior to cell division to ensure each daughter cell receives the full complement of chromosomes. DNA synthesis of daughter strands starts at discrete sites, termed replication origins, and proceeds in a bidirectional manner until all genomic DNA is replicated. Despite the fundamental nature of these events, organisms have evolved surprisingly divergent strategies that control replication onset. Here, we discuss commonalities and differences in replication origin organization and recognition in the three domains of life.
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Affiliation(s)
- Babatunde Ekundayo
- Quantitative Biology, Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Franziska Bleichert
- Quantitative Biology, Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
- * E-mail:
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9
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Rivera-Mulia JC, Kim S, Gabr H, Chakraborty A, Ay F, Kahveci T, Gilbert DM. Replication timing networks reveal a link between transcription regulatory circuits and replication timing control. Genome Res 2019; 29:1415-1428. [PMID: 31434679 PMCID: PMC6724675 DOI: 10.1101/gr.247049.118] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2018] [Accepted: 08/05/2019] [Indexed: 12/11/2022]
Abstract
DNA replication occurs in a defined temporal order known as the replication timing (RT) program and is regulated during development, coordinated with 3D genome organization and transcriptional activity. However, transcription and RT are not sufficiently coordinated to predict each other, suggesting an indirect relationship. Here, we exploit genome-wide RT profiles from 15 human cell types and intermediate differentiation stages derived from human embryonic stem cells to construct different types of RT regulatory networks. First, we constructed networks based on the coordinated RT changes during cell fate commitment to create highly complex RT networks composed of thousands of interactions that form specific functional subnetwork communities. We also constructed directional regulatory networks based on the order of RT changes within cell lineages, and identified master regulators of differentiation pathways. Finally, we explored relationships between RT networks and transcriptional regulatory networks (TRNs) by combining them into more complex circuitries of composite and bipartite networks. Results identified novel trans interactions linking transcription factors that are core to the regulatory circuitry of each cell type to RT changes occurring in those cell types. These core transcription factors were found to bind cooperatively to sites in the affected replication domains, providing provocative evidence that they constitute biologically significant directional interactions. Our findings suggest a regulatory link between the establishment of cell-type-specific TRNs and RT control during lineage specification.
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Affiliation(s)
- Juan Carlos Rivera-Mulia
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota Medical School, Minneapolis, Minnesota 55455, USA
| | - Sebo Kim
- Department of Computer and Information Sciences and Engineering, University of Florida, Gainesville, Florida 32611, USA
| | - Haitham Gabr
- Department of Computer and Information Sciences and Engineering, University of Florida, Gainesville, Florida 32611, USA
| | - Abhijit Chakraborty
- La Jolla Institute for Allergy and Immunology, La Jolla, California 92037, USA
| | - Ferhat Ay
- La Jolla Institute for Allergy and Immunology, La Jolla, California 92037, USA.,School of Medicine, University of California San Diego, La Jolla, California 92093, USA
| | - Tamer Kahveci
- Department of Computer and Information Sciences and Engineering, University of Florida, Gainesville, Florida 32611, USA
| | - David M Gilbert
- Department of Biological Science, Florida State University, Tallahassee, Florida, 32306-4295, USA.,Center for Genomics and Personalized Medicine, Florida State University, Tallahassee, Florida 32306, USA
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10
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Merchut-Maya JM, Bartek J, Maya-Mendoza A. Regulation of replication fork speed: Mechanisms and impact on genomic stability. DNA Repair (Amst) 2019; 81:102654. [PMID: 31320249 DOI: 10.1016/j.dnarep.2019.102654] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Replication of DNA is a fundamental biological process that ensures precise duplication of the genome and thus safeguards inheritance. Any errors occurring during this process must be repaired before the cell divides, by activating the DNA damage response (DDR) machinery that detects and corrects the DNA lesions. Consistent with its significance, DNA replication is under stringent control, both spatial and temporal. Defined regions of the genome are replicated at specific times during S phase and the speed of replication fork progression is adjusted to fully replicate DNA in pace with the cell cycle. Insults that impair DNA replication cause replication stress (RS), which can lead to genomic instability and, potentially, to cell transformation. In this perspective, we review the current concept of replication stress, including the recent findings on the effects of accelerated fork speed and their impact on genomic (in)stability. We discuss in detail the Fork Speed Regulatory Network (FSRN), an integrated molecular machinery that regulates the velocity of DNA replication forks. Finally, we explore the potential for targeting FSRN components as an avenue to treat cancer.
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Affiliation(s)
- Joanna Maria Merchut-Maya
- DNA Replication and Cancer Group, Genome Integrity Unit, Danish Cancer Society Research Center, Copenhagen, Denmark
| | - Jiri Bartek
- Genome Integrity Unit, Danish Cancer Society Research Center, Copenhagen, Denmark; Department of Medical Biochemistry and Biophysics, Division of Genome Biology, Science for Life Laboratory, Karolinska Institute, Stockholm, Sweden.
| | - Apolinar Maya-Mendoza
- DNA Replication and Cancer Group, Genome Integrity Unit, Danish Cancer Society Research Center, Copenhagen, Denmark.
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11
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Zhang H, Petrie MV, He Y, Peace JM, Chiolo IE, Aparicio OM. Dynamic relocalization of replication origins by Fkh1 requires execution of DDK function and Cdc45 loading at origins. eLife 2019; 8:45512. [PMID: 31084713 PMCID: PMC6533057 DOI: 10.7554/elife.45512] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Accepted: 05/13/2019] [Indexed: 12/11/2022] Open
Abstract
Chromosomal DNA elements are organized into spatial domains within the eukaryotic nucleus. Sites undergoing DNA replication, high-level transcription, and repair of double-strand breaks coalesce into foci, although the significance and mechanisms giving rise to these dynamic structures are poorly understood. In S. cerevisiae, replication origins occupy characteristic subnuclear localizations that anticipate their initiation timing during S phase. Here, we link localization of replication origins in G1 phase with Fkh1 activity, which is required for their early replication timing. Using a Fkh1-dependent origin relocalization assay, we determine that execution of Dbf4-dependent kinase function, including Cdc45 loading, results in dynamic relocalization of a replication origin from the nuclear periphery to the interior in G1 phase. Origin mobility increases substantially with Fkh1-driven relocalization. These findings provide novel molecular insight into the mechanisms that govern dynamics and spatial organization of DNA replication origins and possibly other functional DNA elements.
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Affiliation(s)
- Haiyang Zhang
- Molecular and Computational Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, United States
| | - Meghan V Petrie
- Molecular and Computational Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, United States
| | - Yiwei He
- Molecular and Computational Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, United States
| | - Jared M Peace
- Molecular and Computational Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, United States
| | - Irene E Chiolo
- Molecular and Computational Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, United States
| | - Oscar M Aparicio
- Molecular and Computational Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, United States
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12
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Palumbo E, Russo A. Common fragile site instability in normal cells: Lessons and perspectives. Genes Chromosomes Cancer 2018; 58:260-269. [PMID: 30387295 DOI: 10.1002/gcc.22705] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 09/25/2018] [Accepted: 10/01/2018] [Indexed: 12/26/2022] Open
Abstract
Mechanisms and events related to common fragile site (CFS) instability are well known in cancer cells. Here, we argue that normal cells remain an important experimental model to address questions related to CFS instability in the absence of alterations in cell cycle and DNA damage repair pathways, which are common features acquired in cancer. Furthermore, a major gap of knowledge concerns the stability of CFSs during gametogenesis. CFS instability in meiotic or postmeiotic stages of the germ cell line could generate chromosome deletions or large rearrangements. This in turn can lead to the functional loss of the several CFS-associated genes with tumor suppressor function. Our hypothesis is that such mutations can potentially result in genetic predisposition to develop cancer. Indirect evidence for CFS instability in human germ cells has been provided by genomic investigations in family pedigrees associated with genetic disease. The issue of CFS instability in the germ cell line should represent one of the future efforts, and may take advantage of the existence of sequence and functional conservation of CFSs between rodents and humans.
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Affiliation(s)
- Elisa Palumbo
- Department of Molecular Medicine, University of Padova, Padova, Italy
| | - Antonella Russo
- Department of Molecular Medicine, University of Padova, Padova, Italy
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