1
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Hu J, Crickard JB. All who wander are not lost: the search for homology during homologous recombination. Biochem Soc Trans 2024; 52:367-377. [PMID: 38323621 PMCID: PMC10903458 DOI: 10.1042/bst20230705] [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: 11/17/2023] [Revised: 01/10/2024] [Accepted: 01/12/2024] [Indexed: 02/08/2024]
Abstract
Homologous recombination (HR) is a template-based DNA double-strand break repair pathway that functions to maintain genomic integrity. A vital component of the HR reaction is the identification of template DNA to be used during repair. This occurs through a mechanism known as the homology search. The homology search occurs in two steps: a collision step in which two pieces of DNA are forced to collide and a selection step that results in homologous pairing between matching DNA sequences. Selection of a homologous template is facilitated by recombinases of the RecA/Rad51 family of proteins in cooperation with helicases, translocases, and topoisomerases that determine the overall fidelity of the match. This menagerie of molecular machines acts to regulate critical intermediates during the homology search. These intermediates include recombinase filaments that probe for short stretches of homology and early strand invasion intermediates in the form of displacement loops (D-loops) that stabilize paired DNA. Here, we will discuss recent advances in understanding how these specific intermediates are regulated on the molecular level during the HR reaction. We will also discuss how the stability of these intermediates influences the ultimate outcomes of the HR reaction. Finally, we will discuss recent physiological models developed to explain how the homology search protects the genome.
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Affiliation(s)
- Jingyi Hu
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, U.S.A
| | - J Brooks Crickard
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, U.S.A
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2
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Li H, Playter C, Das P, McCord RP. Chromosome compartmentalization: causes, changes, consequences, and conundrums. Trends Cell Biol 2024:S0962-8924(24)00021-7. [PMID: 38395734 DOI: 10.1016/j.tcb.2024.01.009] [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: 10/31/2023] [Revised: 01/12/2024] [Accepted: 01/22/2024] [Indexed: 02/25/2024]
Abstract
The spatial segregation of the genome into compartments is a major feature of 3D genome organization. New data on mammalian chromosome organization across different conditions reveal important information about how and why these compartments form and change. A combination of epigenetic state, nuclear body tethering, physical forces, gene expression, and replication timing (RT) can all influence the establishment and alteration of chromosome compartments. We review the causes and implications of genomic regions undergoing a 'compartment switch' that changes their physical associations and spatial location in the nucleus. About 20-30% of genomic regions change compartment during cell differentiation or cancer progression, whereas alterations in response to a stimulus within a cell type are usually much more limited. However, even a change in 1-2% of genomic bins may have biologically relevant implications. Finally, we review the effects of compartment changes on gene regulation, DNA damage repair, replication, and the physical state of the cell.
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Affiliation(s)
- Heng Li
- Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, TN, USA
| | - Christopher Playter
- Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, TN, USA
| | - Priyojit Das
- University of Tennessee-Oak Ridge National Laboratory (UT-ORNL) Graduate School of Genome Science and Technology, University of Tennessee, Knoxville, TN, USA
| | - Rachel Patton McCord
- Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, TN, USA.
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3
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Wang YL, Zhao WW, Shi J, Wan XB, Zheng J, Fan XJ. Liquid-liquid phase separation in DNA double-strand breaks repair. Cell Death Dis 2023; 14:746. [PMID: 37968256 PMCID: PMC10651886 DOI: 10.1038/s41419-023-06267-0] [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: 12/26/2022] [Revised: 10/23/2023] [Accepted: 11/01/2023] [Indexed: 11/17/2023]
Abstract
DNA double-strand breaks (DSBs) are the fatal type of DNA damage mostly induced by exposure genome to ionizing radiation or genotoxic chemicals. DSBs are mainly repaired by homologous recombination (HR) and nonhomologous end joining (NHEJ). To repair DSBs, a large amount of DNA repair factors was observed to be concentrated at the end of DSBs in a specific spatiotemporal manner to form a repair center. Recently, this repair center was characterized as a condensate derived from liquid-liquid phase separation (LLPS) of key DSBs repair factors. LLPS has been found to be the mechanism of membraneless organelles formation and plays key roles in a variety of biological processes. In this review, the recent advances and mechanisms of LLPS in the formation of DSBs repair-related condensates are summarized.
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Affiliation(s)
- Yun-Long Wang
- Henan Provincial Key Laboratory of Radiation Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, 450052, PR China
- Academy of Medical Sciences, Zhengzhou University, Zhengzhou, Henan, 450052, PR China
- Department of Radiation Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, 450052, PR China
- Department of Radiation Oncology, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, 510655, PR China
| | - Wan-Wen Zhao
- Department of Radiation Oncology, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, 510655, PR China
- GuangDong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, 510655, PR China
| | - Jie Shi
- Department of Radiation Oncology, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, 510655, PR China
- GuangDong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, 510655, PR China
| | - Xiang-Bo Wan
- Henan Provincial Key Laboratory of Radiation Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, 450052, PR China
- Academy of Medical Sciences, Zhengzhou University, Zhengzhou, Henan, 450052, PR China
- Department of Radiation Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, 450052, PR China
- Department of Radiation Oncology, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, 510655, PR China
| | - Jian Zheng
- Department of Radiation Oncology, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, 510655, PR China
- GuangDong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, 510655, PR China
| | - Xin-Juan Fan
- Henan Provincial Key Laboratory of Radiation Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, 450052, PR China.
- Academy of Medical Sciences, Zhengzhou University, Zhengzhou, Henan, 450052, PR China.
- GuangDong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, 510655, PR China.
- Department of Pathology, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, 510655, PR China.
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4
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Phipps J, Dubrana K. DNA Repair in Space and Time: Safeguarding the Genome with the Cohesin Complex. Genes (Basel) 2022; 13:198. [PMID: 35205243 PMCID: PMC8872453 DOI: 10.3390/genes13020198] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Revised: 01/20/2022] [Accepted: 01/20/2022] [Indexed: 12/04/2022] Open
Abstract
DNA double-strand breaks (DSBs) are a deleterious form of DNA damage, which must be robustly addressed to ensure genome stability. Defective repair can result in chromosome loss, point mutations, loss of heterozygosity or chromosomal rearrangements, which could lead to oncogenesis or cell death. We explore the requirements for the successful repair of DNA DSBs by non-homologous end joining and homology-directed repair (HDR) mechanisms in relation to genome folding and dynamics. On the occurrence of a DSB, local and global chromatin composition and dynamics, as well as 3D genome organization and break localization within the nuclear space, influence how repair proceeds. The cohesin complex is increasingly implicated as a key regulator of the genome, influencing chromatin composition and dynamics, and crucially genome organization through folding chromosomes by an active loop extrusion mechanism, and maintaining sister chromatid cohesion. Here, we consider how this complex is now emerging as a key player in the DNA damage response, influencing repair pathway choice and efficiency.
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Affiliation(s)
| | - Karine Dubrana
- UMR Stabilité Génétique Cellules Souches et Radiations, INSERM, iRCM/IBFJ CEA, Université de Paris and Université Paris-Saclay, F-92265 Fontenay-aux-Roses, France;
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5
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Wen J, Wang Y, Yuan M, Huang Z, Zou Q, Pu Y, Zhao B, Cai Z. Role of mismatch repair in aging. Int J Biol Sci 2021; 17:3923-3935. [PMID: 34671209 PMCID: PMC8495402 DOI: 10.7150/ijbs.64953] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Accepted: 09/07/2021] [Indexed: 01/10/2023] Open
Abstract
A common feature of aging is the accumulation of genetic damage throughout life. DNA damage can lead to genomic instability. Many diseases associated with premature aging are a result of increased accumulation of DNA damage. In order to minimize these damages, organisms have evolved a complex network of DNA repair mechanisms, including mismatch repair (MMR). In this review, we detail the effects of MMR on genomic instability and its role in aging emphasizing on the association between MMR and the other hallmarks of aging, serving to drive or amplify these mechanisms. These hallmarks include telomere attrition, epigenetic alterations, mitochondrial dysfunction, altered nutrient sensing and cell senescence. The close relationship between MMR and these markers may provide prevention and treatment strategies, to reduce the incidence of age-related diseases and promote the healthy aging of human beings.
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Affiliation(s)
- Jie Wen
- Chongqing Key Laboratory of Neurodegenerative Diseases, Chongqing, 400013, China.,Department of Neurology, Chongqing General Hospital, University of Chinese Academy of Sciences, Chongqing, 400013, China.,Department and Institute of Neurology, Guangdong Medical University, Guangdong, 524001, China.,Guangdong Key Laboratory of aging related cardio cerebral diseases, Guangdong, 524001, China
| | - Yangyang Wang
- Chongqing Key Laboratory of Neurodegenerative Diseases, Chongqing, 400013, China.,Department of Neurology, Chongqing General Hospital, University of Chinese Academy of Sciences, Chongqing, 400013, China
| | - Minghao Yuan
- Chongqing Key Laboratory of Neurodegenerative Diseases, Chongqing, 400013, China.,Department of Neurology, Chongqing General Hospital, University of Chinese Academy of Sciences, Chongqing, 400013, China
| | - Zhenting Huang
- Chongqing Key Laboratory of Neurodegenerative Diseases, Chongqing, 400013, China.,Department of Neurology, Chongqing General Hospital, University of Chinese Academy of Sciences, Chongqing, 400013, China
| | - Qian Zou
- Chongqing Key Laboratory of Neurodegenerative Diseases, Chongqing, 400013, China.,Department of Neurology, Chongqing General Hospital, University of Chinese Academy of Sciences, Chongqing, 400013, China
| | - Yinshuang Pu
- Chongqing Key Laboratory of Neurodegenerative Diseases, Chongqing, 400013, China.,Department of Neurology, Chongqing General Hospital, University of Chinese Academy of Sciences, Chongqing, 400013, China
| | - Bin Zhao
- Department and Institute of Neurology, Guangdong Medical University, Guangdong, 524001, China.,Guangdong Key Laboratory of aging related cardio cerebral diseases, Guangdong, 524001, China
| | - Zhiyou Cai
- Chongqing Key Laboratory of Neurodegenerative Diseases, Chongqing, 400013, China.,Department of Neurology, Chongqing General Hospital, University of Chinese Academy of Sciences, Chongqing, 400013, China
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6
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Disruption of Chromatin Dynamics by Hypotonic Stress Suppresses HR and Shifts DSB Processing to Error-Prone SSA. Int J Mol Sci 2021; 22:ijms222010957. [PMID: 34681628 PMCID: PMC8535785 DOI: 10.3390/ijms222010957] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 10/04/2021] [Accepted: 10/05/2021] [Indexed: 11/17/2022] Open
Abstract
The processing of DNA double-strand breaks (DSBs) depends on the dynamic characteristics of chromatin. To investigate how abrupt changes in chromatin compaction alter these dynamics and affect DSB processing and repair, we exposed irradiated cells to hypotonic stress (HypoS). Densitometric and chromosome-length analyses show that HypoS transiently decompacts chromatin without inducing histone modifications known from regulated local chromatin decondensation, or changes in Micrococcal Nuclease (MNase) sensitivity. HypoS leaves undisturbed initial stages of DNA-damage-response (DDR), such as radiation-induced ATM activation and H2AX-phosphorylation. However, detection of ATM-pS1981, γ-H2AX and 53BP1 foci is reduced in a protein, cell cycle phase and cell line dependent manner; likely secondary to chromatin decompaction that disrupts the focal organization of DDR proteins. While HypoS only exerts small effects on classical nonhomologous end-joining (c-NHEJ) and alternative end-joining (alt-EJ), it markedly suppresses homologous recombination (HR) without affecting DNA end-resection at DSBs, and clearly enhances single-strand annealing (SSA). These shifts in pathway engagement are accompanied by decreases in HR-dependent chromatid-break repair in the G2-phase, and by increases in alt-EJ and SSA-dependent chromosomal translocations. Consequently, HypoS sensitizes cells to ionizing radiation (IR)-induced killing. We conclude that HypoS-induced global chromatin decompaction compromises regulated chromatin dynamics and genomic stability by suppressing DSB-processing by HR, and allowing error-prone processing by alt-EJ and SSA.
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7
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ATM controls the extent of DNA end resection by eliciting sequential posttranslational modifications of CtIP. Proc Natl Acad Sci U S A 2021; 118:2022600118. [PMID: 33723063 DOI: 10.1073/pnas.2022600118] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
DNA end resection is a critical step in the repair of DNA double-strand breaks (DSBs) via homologous recombination (HR). However, the mechanisms governing the extent of resection at DSB sites undergoing homology-directed repair remain unclear. Here, we show that, upon DSB induction, the key resection factor CtIP is modified by the ubiquitin-like protein SUMO at lysine 578 in a PIAS4-dependent manner. CtIP SUMOylation occurs on damaged chromatin and requires prior hyperphosphorylation by the ATM protein kinase. SUMO-modified hyperphosphorylated CtIP is targeted by the SUMO-dependent E3 ubiquitin ligase RNF4 for polyubiquitination and subsequent degradation. Consequently, disruption of CtIP SUMOylation results in aberrant accumulation of CtIP at DSBs, which, in turn, causes uncontrolled excessive resection, defective HR, and increased cellular sensitivity to DSB-inducing agents. These findings reveal a previously unidentified regulatory mechanism that regulates CtIP activity at DSBs and thus the extent of end resection via ATM-dependent sequential posttranslational modification of CtIP.
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8
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Hawkins CJ, Miles MA. Mutagenic Consequences of Sublethal Cell Death Signaling. Int J Mol Sci 2021; 22:ijms22116144. [PMID: 34200309 PMCID: PMC8201051 DOI: 10.3390/ijms22116144] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 06/03/2021] [Accepted: 06/05/2021] [Indexed: 02/06/2023] Open
Abstract
Many human cancers exhibit defects in key DNA damage response elements that can render tumors insensitive to the cell death-promoting properties of DNA-damaging therapies. Using agents that directly induce apoptosis by targeting apoptotic components, rather than relying on DNA damage to indirectly stimulate apoptosis of cancer cells, may overcome classical blocks exploited by cancer cells to evade apoptotic cell death. However, there is increasing evidence that cells surviving sublethal exposure to classical apoptotic signaling may recover with newly acquired genomic changes which may have oncogenic potential, and so could theoretically spur the development of subsequent cancers in cured patients. Encouragingly, cells surviving sublethal necroptotic signaling did not acquire mutations, suggesting that necroptosis-inducing anti-cancer drugs may be less likely to trigger therapy-related cancers. We are yet to develop effective direct inducers of other cell death pathways, and as such, data regarding the consequences of cells surviving sublethal stimulation of those pathways are still emerging. This review details the currently known mutagenic consequences of cells surviving different cell death signaling pathways, with implications for potential oncogenic transformation. Understanding the mechanisms of mutagenesis associated (or not) with various cell death pathways will guide us in the development of future therapeutics to minimize therapy-related side effects associated with DNA damage.
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Affiliation(s)
- Christine J. Hawkins
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Bundoora, VIC 3086, Australia;
| | - Mark A. Miles
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Bundoora, VIC 3086, Australia;
- School of Health and Biomedical Sciences, RMIT University, Bundoora, VIC 3083, Australia
- Correspondence:
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9
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Miné-Hattab J, Heltberg M, Villemeur M, Guedj C, Mora T, Walczak AM, Dahan M, Taddei A. Single molecule microscopy reveals key physical features of repair foci in living cells. eLife 2021; 10:60577. [PMID: 33543712 PMCID: PMC7924958 DOI: 10.7554/elife.60577] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 01/26/2021] [Indexed: 12/20/2022] Open
Abstract
In response to double strand breaks (DSB), repair proteins accumulate at damaged sites, forming membrane-less sub-compartments or foci. Here we explored the physical nature of these foci, using single molecule microscopy in living cells. Rad52, the functional homolog of BRCA2 in yeast, accumulates at DSB sites and diffuses ~6 times faster within repair foci than the focus itself, exhibiting confined motion. The Rad52 confinement radius coincides with the focus size: foci resulting from 2 DSBs are twice larger in volume that the ones induced by a unique DSB and the Rad52 confinement radius scales accordingly. In contrast, molecules of the single strand binding protein Rfa1 follow anomalous diffusion similar to the focus itself or damaged chromatin. We conclude that while most Rfa1 molecules are bound to the ssDNA, Rad52 molecules are free to explore the entire focus reflecting the existence of a liquid droplet around damaged DNA.
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Affiliation(s)
- Judith Miné-Hattab
- Institut Curie, PSL University, Sorbonne Université, CNRS, Nuclear Dynamics, Paris, France
| | - Mathias Heltberg
- Institut Curie, PSL University, Sorbonne Université, CNRS, Nuclear Dynamics, Paris, France.,Laboratoire de Physique de l'Ecole Normale Supérieure, PSL University, CNRS, Sorbonne Université , Université de Paris, Paris, France
| | - Marie Villemeur
- Institut Curie, PSL University, Sorbonne Université, CNRS, Nuclear Dynamics, Paris, France
| | - Chloé Guedj
- Institut Curie, PSL University, Sorbonne Université, CNRS, Nuclear Dynamics, Paris, France
| | - Thierry Mora
- Laboratoire de Physique de l'Ecole Normale Supérieure, PSL University, CNRS, Sorbonne Université , Université de Paris, Paris, France
| | - Aleksandra M Walczak
- Laboratoire de Physique de l'Ecole Normale Supérieure, PSL University, CNRS, Sorbonne Université , Université de Paris, Paris, France
| | - Maxime Dahan
- Institut Curie, PSL University, Sorbonne Université, CNRS, Physico Chimie Curie, Paris, France
| | - Angela Taddei
- Institut Curie, PSL University, Sorbonne Université, CNRS, Nuclear Dynamics, Paris, France.,Cogitamus Laboratory, Paris, France
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10
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Mackenroth B, Alani E. Collaborations between chromatin and nuclear architecture to optimize DNA repair fidelity. DNA Repair (Amst) 2021; 97:103018. [PMID: 33285474 PMCID: PMC8486310 DOI: 10.1016/j.dnarep.2020.103018] [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: 07/30/2020] [Revised: 10/18/2020] [Accepted: 11/05/2020] [Indexed: 01/22/2023]
Abstract
Homologous recombination (HR), considered the highest fidelity DNA double-strand break (DSB) repair pathway that a cell possesses, is capable of repairing multiple DSBs without altering genetic information. However, in "last resort" scenarios, HR can be directed to low fidelity subpathways which often use non-allelic donor templates. Such repair mechanisms are often highly mutagenic and can also yield chromosomal rearrangements and/or deletions. While the choice between HR and its less precise counterpart, non-homologous end joining (NHEJ), has received much attention, less is known about how cells manage and prioritize HR subpathways. In this review, we describe work focused on how chromatin and nuclear architecture orchestrate subpathway choice and repair template usage to maintain genome integrity without sacrificing cell survival. Understanding the relationships between nuclear architecture and recombination mechanics will be critical to understand these cellular repair decisions.
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Affiliation(s)
- Beata Mackenroth
- Department of Molecular Biology and Genetics, Cornell University, 459 Biotechnology Building, Ithaca, NY, 14853-2703, United States
| | - Eric Alani
- Department of Molecular Biology and Genetics, Cornell University, 459 Biotechnology Building, Ithaca, NY, 14853-2703, United States.
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11
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Falk M, Hausmann M. A Paradigm Revolution or Just Better Resolution-Will Newly Emerging Superresolution Techniques Identify Chromatin Architecture as a Key Factor in Radiation-Induced DNA Damage and Repair Regulation? Cancers (Basel) 2020; 13:E18. [PMID: 33374540 PMCID: PMC7793109 DOI: 10.3390/cancers13010018] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 12/18/2020] [Indexed: 02/07/2023] Open
Abstract
DNA double-strand breaks (DSBs) have been recognized as the most serious lesions in irradiated cells. While several biochemical pathways capable of repairing these lesions have been identified, the mechanisms by which cells select a specific pathway for activation at a given DSB site remain poorly understood. Our knowledge of DSB induction and repair has increased dramatically since the discovery of ionizing radiation-induced foci (IRIFs), initiating the possibility of spatiotemporally monitoring the assembly and disassembly of repair complexes in single cells. IRIF exploration revealed that all post-irradiation processes-DSB formation, repair and misrepair-are strongly dependent on the characteristics of DSB damage and the microarchitecture of the whole affected chromatin domain in addition to the cell status. The microscale features of IRIFs, such as their morphology, mobility, spatiotemporal distribution, and persistence kinetics, have been linked to repair mechanisms. However, the influence of various biochemical and structural factors and their specific combinations on IRIF architecture remains unknown, as does the hierarchy of these factors in the decision-making process for a particular repair mechanism at each individual DSB site. New insights into the relationship between the physical properties of the incident radiation, chromatin architecture, IRIF architecture, and DSB repair mechanisms and repair efficiency are expected from recent developments in optical superresolution microscopy (nanoscopy) techniques that have shifted our ability to analyze chromatin and IRIF architectures towards the nanoscale. In the present review, we discuss this relationship, attempt to correlate still rather isolated nanoscale studies with already better-understood aspects of DSB repair at the microscale, and consider whether newly emerging "correlated multiscale structuromics" can revolutionarily enhance our knowledge in this field.
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Affiliation(s)
- Martin Falk
- Institute of Biophysics, The Czech Academy of Sciences, 612 65 Brno, Czech Republic
| | - Michael Hausmann
- Kirchhoff Institute for Physics, Heidelberg University, 69120 Heidelberg, Germany;
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12
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Blokhina YP, Buchwalter A. Moving fast and breaking things: Incidence and repair of DNA damage within ribosomal DNA repeats. Mutat Res 2020; 821:111715. [PMID: 32717383 DOI: 10.1016/j.mrfmmm.2020.111715] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 06/25/2020] [Accepted: 07/13/2020] [Indexed: 12/31/2022]
Abstract
The genes that code for ribosomal RNA are present in hundreds of tandemly arrayed copies in the human genome. Ribosomal DNA repeats transcribe vast amounts of ribosomal RNA in order to meet the cell's relentless demand for ribosome production. Intrinsic features of ribosomal DNA repeats render them uniquely vulnerable to DNA damage. Sensing and repairing damage to ribosomal DNA involves dramatic spatial reorganization of the nucleolus, the phase-separated nuclear subdomain where ribosomes are made. We highlight recent advances in detecting the incidence of DNA damage and defining the mechanisms of DNA repair on these essential genes.
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Affiliation(s)
- Yana P Blokhina
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA, United States
| | - Abigail Buchwalter
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA, United States; Department of Physiology, University of California, San Francisco, San Francisco, CA, United States; Chan Zuckerberg Biohub, San Francisco, CA, United States.
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13
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Karakaidos P, Karagiannis D, Rampias T. Resolving DNA Damage: Epigenetic Regulation of DNA Repair. Molecules 2020; 25:molecules25112496. [PMID: 32471288 PMCID: PMC7321228 DOI: 10.3390/molecules25112496] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 05/22/2020] [Accepted: 05/25/2020] [Indexed: 12/18/2022] Open
Abstract
Epigenetic research has rapidly evolved into a dynamic field of genome biology. Chromatin regulation has been proved to be an essential aspect for all genomic processes, including DNA repair. Chromatin structure is modified by enzymes and factors that deposit, erase, and interact with epigenetic marks such as DNA and histone modifications, as well as by complexes that remodel nucleosomes. In this review we discuss recent advances on how the chromatin state is modulated during this multi-step process of damage recognition, signaling, and repair. Moreover, we examine how chromatin is regulated when different pathways of DNA repair are utilized. Furthermore, we review additional modes of regulation of DNA repair, such as through the role of global and localized chromatin states in maintaining expression of DNA repair genes, as well as through the activity of epigenetic enzymes on non-nucleosome substrates. Finally, we discuss current and future applications of the mechanistic interplays between chromatin regulation and DNA repair in the context cancer treatment.
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Affiliation(s)
| | - Dimitris Karagiannis
- Department of Genetics and Development, Columbia University Medical Center, New York, NY 10032, USA;
| | - Theodoros Rampias
- Biomedical Research Foundation of the Academy of Athens, 11527 Athens, Greece;
- Correspondence: ; Tel.: +30-210-659-7469
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14
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Ngo K, Epum EA, Friedman KL. Emerging non-canonical roles for the Rad51-Rad52 interaction in response to double-strand breaks in yeast. Curr Genet 2020; 66:917-926. [PMID: 32399607 DOI: 10.1007/s00294-020-01081-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 04/28/2020] [Accepted: 04/29/2020] [Indexed: 12/24/2022]
Abstract
DNA double-strand break repair allows cells to survive both exogenous and endogenous insults to the genome. In yeast, the recombinases Rad51 and Rad52 are central to multiple forms of homology-dependent repair. Classically, Rad51 and Rad52 are thought to act cooperatively, with formation of the functional Rad51 nucleofilament facilitated by the mediator function of Rad52. Several studies have now identified functions for the interaction between Rad51 and Rad52 that are independent of the mediator function of Rad52 and affect a seemingly diverse array of functions in de novo telomere addition, global chromosome mobility following DNA damage, Rad51 nucleofilament stability, checkpoint adaptation, and microhomology-mediated chromosome rearrangements. Here, we review these functions with an emphasis on our recent discovery that the Rad51-Rad52 interaction influences the probability of de novo telomere addition at sites preferentially targeted by telomerase following a double-strand break (DSB). We present data addressing the prevalence of sites within the yeast genome that are capable of stimulating de novo telomere addition following a DSB and speculate about the potential role such sites may play in genome stability.
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Affiliation(s)
- Katrina Ngo
- Department of Biological Sciences, Vanderbilt University, Nashville, TN, USA
| | - Esther A Epum
- Department of Biological Sciences, Vanderbilt University, Nashville, TN, USA
- Department of Biology, Rosenstiel Basic Medical Sciences Research Center, Brandeis University, Waltham, MA, USA
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15
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Arbel M, Liefshitz B, Kupiec M. How yeast cells deal with stalled replication forks. Curr Genet 2020; 66:911-915. [PMID: 32394094 DOI: 10.1007/s00294-020-01082-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 04/24/2020] [Accepted: 04/29/2020] [Indexed: 12/27/2022]
Abstract
DNA polymerases sometimes stall during DNA replication at sites where DNA is damaged, or upon encounter with proteins or secondary structures of DNA. When that happens, the polymerase clamp PCNA can become modified with a single ubiquitin moiety at lysine 164, opening DNA Damage Tolerance (DDT) mechanisms that either repair or bypass the lesions. An alternative repair mechanism is the salvage recombination (SR) pathway, which copies information from the sister chromatid. SUMOylation of PCNA at the same lysine, or at lysine 127, can recruit the Srs2 helicase, which negatively controls SR. Recently, we have dissected the relationship between SR and the DDT pathways, and showed that overexpression of either the PCNA unloader Elg1, or the Rad52 homologous recombination protein, can bypass the repression by Srs2. Our results shed light on the interactions between different DNA damage repair/bypass proteins, and underscore the importance of PCNA modifications in organizing the complex task of dealing with DNA damage during replication of the genetic material.
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Affiliation(s)
- Matan Arbel
- School of Molecular Cell Biology and Biotechnology, Tel Aviv University, 69978, Ramat, Aviv, Israel
| | - Batia Liefshitz
- School of Molecular Cell Biology and Biotechnology, Tel Aviv University, 69978, Ramat, Aviv, Israel
| | - Martin Kupiec
- School of Molecular Cell Biology and Biotechnology, Tel Aviv University, 69978, Ramat, Aviv, Israel.
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16
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Hiraoka Y. Phase separation drives pairing of homologous chromosomes. Curr Genet 2020; 66:881-887. [PMID: 32285141 DOI: 10.1007/s00294-020-01077-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 04/04/2020] [Accepted: 04/06/2020] [Indexed: 01/06/2023]
Abstract
Pairing of homologous chromosomes is crucial for ensuring accurate segregation of chromosomes during meiosis. Molecular mechanisms of homologous chromosome pairing in meiosis have been extensively studied in the fission yeast Schizosaccharomyces pombe. In this organism, meiosis-specific noncoding RNA transcribed from specific genes accumulates at the respective gene loci, and chromosome-associated RNA-protein complexes mediate meiotic pairing of homologous loci through phase separation. Pairing of homologous chromosomes also occurs in somatic diploid cells in certain situations. For example, somatic pairing of homologous chromosomes occurs during the early embryogenesis in diptera, and relies on the transcription-associated chromatin architecture. Earlier models also suggest that transcription factories along the chromosome mediate pairing of homologous chromosomes in plants. These studies suggest that RNA bodies formed on chromosomes mediate the pairing of homologous chromosomes. This review summarizes lessons from S. pombe to provide general insights into mechanisms of homologous chromosome pairing mediated by phase separation of chromosome-associated RNA-protein complexes.
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Affiliation(s)
- Yasushi Hiraoka
- Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka, Suita, 565-0871, Japan.
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17
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Harari Y, Gershon L, Alonso-Perez E, Klein S, Berneman Y, Choudhari K, Singh P, Sau S, Liefshitz B, Kupiec M. Telomeres and stress in yeast cells: When genes and environment interact. Fungal Biol 2019; 124:311-315. [PMID: 32389293 DOI: 10.1016/j.funbio.2019.09.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 09/09/2019] [Accepted: 09/09/2019] [Indexed: 12/27/2022]
Abstract
Telomeres are structures composed of simple DNA repeats and specific proteins that protect the eukaryotic chromosomal ends from degradation, and facilitate the replication of the genome. They are central to the maintenance of the genome integrity, and play important roles in the development of cancer and in the process of aging in humans. The yeast Saccharomyces cerevisiae has greatly contributed to our understanding of basic telomere biology. Our laboratory has carried out systematic screen for mutants that affect telomere length, and identified ∼500 genes that, when mutated, affect telomere length. Remarkably, all ∼500 TLM (Telomere Length Maintenance) genes participate in a very tight homeostatic process, and it is enough to mutate one of them to change the steady-state telomere length. Despite this complex network of balances, it is also possible to change telomere length in yeast by applying several types of external stresses. We summarize our insights about the molecular mechanisms by which genes and environment interact to affect telomere length.
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Affiliation(s)
- Yaniv Harari
- School of Molecular Cell Biology and Biotechnology, Tel Aviv University, Ramat Aviv, 69978, Israel
| | - Lihi Gershon
- School of Molecular Cell Biology and Biotechnology, Tel Aviv University, Ramat Aviv, 69978, Israel
| | - Elisa Alonso-Perez
- School of Molecular Cell Biology and Biotechnology, Tel Aviv University, Ramat Aviv, 69978, Israel
| | - Shir Klein
- School of Molecular Cell Biology and Biotechnology, Tel Aviv University, Ramat Aviv, 69978, Israel
| | - Yael Berneman
- School of Molecular Cell Biology and Biotechnology, Tel Aviv University, Ramat Aviv, 69978, Israel
| | - Karan Choudhari
- School of Molecular Cell Biology and Biotechnology, Tel Aviv University, Ramat Aviv, 69978, Israel
| | - Pragyan Singh
- School of Molecular Cell Biology and Biotechnology, Tel Aviv University, Ramat Aviv, 69978, Israel
| | - Soumitra Sau
- Amity Institute of Biotechnology, Amity University Kolkata, Kolkata, India
| | - Batia Liefshitz
- School of Molecular Cell Biology and Biotechnology, Tel Aviv University, Ramat Aviv, 69978, Israel
| | - Martin Kupiec
- School of Molecular Cell Biology and Biotechnology, Tel Aviv University, Ramat Aviv, 69978, Israel.
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18
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Estrem C, Moore JK. Help or hindrance: how do microtubule-based forces contribute to genome damage and repair? Curr Genet 2019; 66:303-311. [PMID: 31501990 DOI: 10.1007/s00294-019-01033-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Revised: 08/27/2019] [Accepted: 08/27/2019] [Indexed: 10/26/2022]
Abstract
Forces generated by molecular motors and the cytoskeleton move the nucleus and genome during many cellular processes, including cell migration and division. How these forces impact the genome, and whether cells regulate cytoskeletal forces to preserve genome integrity is unclear. We recently demonstrated that, in budding yeast, mutants that stabilize the microtubule cytoskeleton cause excessive movement of the mitotic spindle and nucleus. We found that increased nuclear movement results in DNA damage and increased time to repair the damage through homology-directed repair. Our results indicate that nuclear movement impairs DNA repair through increased tension on chromosomes and nuclear deformation. However, the previous studies have shown genome mobility, driven by cytoskeleton-based forces, aids in homology-directed DNA repair. This sets up an apparent paradox, where genome mobility may prevent or promote DNA repair. Hence, this review explores how the genome is affected by nuclear movement and how genome mobility could aid or hinder homology-directed repair.
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Affiliation(s)
- Cassi Estrem
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Jeffrey K Moore
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, CO, USA.
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19
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Marnef A, Finoux AL, Arnould C, Guillou E, Daburon V, Rocher V, Mangeat T, Mangeot PE, Ricci EP, Legube G. A cohesin/HUSH- and LINC-dependent pathway controls ribosomal DNA double-strand break repair. Genes Dev 2019; 33:1175-1190. [PMID: 31395742 PMCID: PMC6719620 DOI: 10.1101/gad.324012.119] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Accepted: 06/26/2019] [Indexed: 02/01/2023]
Abstract
The ribosomal DNA (rDNA) represents a particularly unstable locus undergoing frequent breakage. DNA double-strand breaks (DSBs) within rDNA induce both rDNA transcriptional repression and nucleolar segregation, but the link between the two events remains unclear. Here we found that DSBs induced on rDNA trigger transcriptional repression in a cohesin- and HUSH (human silencing hub) complex-dependent manner throughout the cell cycle. In S/G2 cells, transcriptional repression is further followed by extended resection within the interior of the nucleolus, DSB mobilization at the nucleolar periphery within nucleolar caps, and repair by homologous recombination. We showed that nuclear envelope invaginations frequently connect the nucleolus and that rDNA DSB mobilization, but not transcriptional repression, involves the nuclear envelope-associated LINC complex and the actin pathway. Altogether, our data indicate that rDNA break localization at the nucleolar periphery is not a direct consequence of transcriptional repression but rather is an active process that shares features with the mobilization of persistent DSB in active genes and heterochromatin.
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Affiliation(s)
- Aline Marnef
- Laboratoire de Biologie Cellulaire et Moléculaire du Contrôle de la Prolifération (LBCMCP), Centre de Biologie Intégrative (CBI), Centre National de la Recherche Scientifique (CNRS), Université de Toulouse, Toulouse 31062, France
| | - Anne-Laure Finoux
- Laboratoire de Biologie Cellulaire et Moléculaire du Contrôle de la Prolifération (LBCMCP), Centre de Biologie Intégrative (CBI), Centre National de la Recherche Scientifique (CNRS), Université de Toulouse, Toulouse 31062, France
| | - Coline Arnould
- Laboratoire de Biologie Cellulaire et Moléculaire du Contrôle de la Prolifération (LBCMCP), Centre de Biologie Intégrative (CBI), Centre National de la Recherche Scientifique (CNRS), Université de Toulouse, Toulouse 31062, France
| | - Emmanuelle Guillou
- Laboratoire de Biologie Cellulaire et Moléculaire du Contrôle de la Prolifération (LBCMCP), Centre de Biologie Intégrative (CBI), Centre National de la Recherche Scientifique (CNRS), Université de Toulouse, Toulouse 31062, France
| | - Virginie Daburon
- Laboratoire de Biologie Cellulaire et Moléculaire du Contrôle de la Prolifération (LBCMCP), Centre de Biologie Intégrative (CBI), Centre National de la Recherche Scientifique (CNRS), Université de Toulouse, Toulouse 31062, France
| | - Vincent Rocher
- Laboratoire de Biologie Cellulaire et Moléculaire du Contrôle de la Prolifération (LBCMCP), Centre de Biologie Intégrative (CBI), Centre National de la Recherche Scientifique (CNRS), Université de Toulouse, Toulouse 31062, France
| | - Thomas Mangeat
- Laboratoire de Biologie Cellulaire et Moléculaire du Contrôle de la Prolifération (LBCMCP), Centre de Biologie Intégrative (CBI), Centre National de la Recherche Scientifique (CNRS), Université de Toulouse, Toulouse 31062, France
| | - Philippe E Mangeot
- International Center for Infectiology Research (CIRI), Ecole Normale Supérieure de Lyon (ENS), U1111, Institut National de la Santé et de la Recherche Médicale (INSERM), UMR5308, Centre National de la Recherche Scientifique (CNRS), Université Claude Bernard Lyon 1, Université Lyon, Lyon F-6900, France
| | - Emiliano P Ricci
- Laboratoire de Biologie et Modélisation de la Cellule (LBMC), Ecole Normale Supérieure de Lyon (ENS), U1210, Institut National de la Santé et de la Recherche Médicale (INSERM), UMR5239, Centre National de la Recherche Scientifique (CNRS), Université Claude Bernard Lyon 1, Université de Lyon, Lyon F-69007, France
| | - Gaëlle Legube
- Laboratoire de Biologie Cellulaire et Moléculaire du Contrôle de la Prolifération (LBCMCP), Centre de Biologie Intégrative (CBI), Centre National de la Recherche Scientifique (CNRS), Université de Toulouse, Toulouse 31062, France
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20
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A role for the yeast PCNA unloader Elg1 in eliciting the DNA damage checkpoint. Curr Genet 2019; 66:79-84. [PMID: 31332476 DOI: 10.1007/s00294-019-01020-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2019] [Revised: 07/16/2019] [Accepted: 07/17/2019] [Indexed: 12/28/2022]
Abstract
During cell proliferation, the genome is constantly threatened by cellular and external factors. When the DNA is damaged, or when its faithful duplication is delayed by DNA polymerase stalling, the cells induce a coordinated response termed the DNA damage response (DDR) or checkpoint. Elg1 forms an RFC-like complex in charge of unloading the DNA polymerase processively factor PCNA during DNA replication and DNA repair. Using checkpoint-inducible strains, a recently published paper (Sau et al. in mBio 10(3):e01159-19. https://doi.org/10.1128/mbio.01159-19, 2019) uncovered a role for Elg1 in eliciting the DNA damage checkpoint (DC), one of the branches of the DDR. The apical kinase Mec1/ATR phosphorylates Elg1, as well as the adaptor proteins Rad9/53BP1 and Dpb11/TopBP1, which are recruited to the site of DNA damage to amplify the checkpoint signal. In the absence of Elg1, Rad9 and Dpb11 are recruited but fail to be phosphorylated and the signal is therefore not amplified. Thus, Elg1 appears to coordinate DNA repair and the induction of the DNA damage checkpoint.
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21
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Double-strand breaks in motion: implications for chromosomal rearrangement. Curr Genet 2019; 66:1-6. [PMID: 31321486 DOI: 10.1007/s00294-019-01015-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 07/06/2019] [Accepted: 07/09/2019] [Indexed: 01/01/2023]
Abstract
DNA double-strand breaks (DSBs) must be rejoined properly to prevent the occurrence of serious genomic rearrangements associated with many human diseases. Non-homologous end joining (NHEJ) is a DSB repair mechanism known to protect genomic integrity that is also implicated in creating genomic translocations, inversions, deletions, and insertions. We recently investigated the impact of the pre-damage spatial proximity of DSB-bearing loci on the frequency of trans repair by NHEJ and surprisingly found no correlation between them. In this review, we consider various models that might account for these unexpected results. While DSB movement is necessary to explain our findings, many questions remain about the nature and timing of that motion.
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22
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Moving forward one step back at a time: reversibility during homologous recombination. Curr Genet 2019; 65:1333-1340. [PMID: 31123771 DOI: 10.1007/s00294-019-00995-7] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 05/10/2019] [Accepted: 05/13/2019] [Indexed: 10/26/2022]
Abstract
DNA double-strand breaks are genotoxic lesions whose repair can be templated off an intact DNA duplex through the conserved homologous recombination (HR) pathway. Because it mainly consists of a succession of non-covalent associations of molecules, HR is intrinsically reversible. Reversibility serves as an integral property of HR, exploited and tuned at various stages throughout the pathway with anti- and pro-recombinogenic consequences. Here, we focus on the reversibility of displacement loops (D-loops), a central DNA joint molecule intermediate whose dynamics and regulation have recently been physically probed in somatic S. cerevisiae cells. From homology search to repair completion, we discuss putative roles of D-loop reversibility in repair fidelity and outcome.
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23
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Miné-Hattab J, Taddei A. Physical principles and functional consequences of nuclear compartmentalization in budding yeast. Curr Opin Cell Biol 2019; 58:105-113. [PMID: 30928833 DOI: 10.1016/j.ceb.2019.02.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Revised: 01/28/2019] [Accepted: 02/20/2019] [Indexed: 12/19/2022]
Abstract
One striking feature of eukaryotic nuclei is the existence of discrete regions, in which specific factors concentrate while others are excluded, thus forming microenvironments with different molecular compositions and biological functions. These domains are often referred to as subcompartments even though they are not membrane enclosed. Despite their functional importance the physical nature of these structures remains largely unknown. Here, we describe how the Saccharomyces cerevisiae nucleus is compartmentalized and discuss possible physical models underlying the formation and maintenance of chromatin associated subcompartments. Focusing on three particular examples, the nucleolus, silencing foci, and repair foci, we discuss the biological implications of these different models as well as possible approaches to challenge them in living cells.
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Affiliation(s)
- Judith Miné-Hattab
- Institut Curi-PSL Research University, CNRS, Sorbonne Université, UMR3664, F-75005, Paris, France
| | - Angela Taddei
- Institut Curi-PSL Research University, CNRS, Sorbonne Université, UMR3664, F-75005, Paris, France.
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