1
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Zhang D, Xu S, Luo Z, Lin Z. MOC1 cleaves Holliday junctions through a cooperative nick and counter-nick mechanism mediated by metal ions. Nat Commun 2024; 15:5140. [PMID: 38886375 PMCID: PMC11183143 DOI: 10.1038/s41467-024-49490-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Accepted: 06/06/2024] [Indexed: 06/20/2024] Open
Abstract
Holliday junction resolution is a crucial process in homologous recombination and DNA double-strand break repair. Complete Holliday junction resolution requires two stepwise incisions across the center of the junction, but the precise mechanism of metal ion-catalyzed Holliday junction cleavage remains elusive. Here, we perform a metal ion-triggered catalysis in crystals to investigate the mechanism of Holliday junction cleavage by MOC1. We capture the structures of MOC1 in complex with a nicked Holliday junction at various catalytic states, including the ground state, the one-metal ion binding state, and the two-metal ion binding state. Moreover, we also identify a third metal ion that may aid in the nucleophilic attack on the scissile phosphate. Further structural and biochemical analyses reveal a metal ion-mediated allosteric regulation between the two active sites, contributing to the enhancement of the second strand cleavage following the first strand cleavage, as well as the precise symmetric cleavage across the Holliday junction. Our work provides insights into the mechanism of metal ion-catalyzed Holliday junction resolution by MOC1, with implications for understanding how cells preserve genome integrity during the Holliday junction resolution phase.
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Affiliation(s)
- Danping Zhang
- College of Chemistry, Fuzhou University, Fuzhou, 350108, China
| | - Shenjie Xu
- MOE Key Laboratory of Geriatric Diseases and Immunology, Institute of Molecular Enzymology, School of Biology and Basic Medical Sciences, Suzhou Medical College, Soochow University, Suzhou, 215123, China
| | - Zhipu Luo
- MOE Key Laboratory of Geriatric Diseases and Immunology, Institute of Molecular Enzymology, School of Biology and Basic Medical Sciences, Suzhou Medical College, Soochow University, Suzhou, 215123, China.
| | - Zhonghui Lin
- College of Chemistry, Fuzhou University, Fuzhou, 350108, China.
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2
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Tse YWE, Yun HY, Wyatt HDM. Annealing and purification of fluorescently labeled DNA substrates for in vitro assays. STAR Protoc 2023; 4:102128. [PMID: 36853679 PMCID: PMC9958487 DOI: 10.1016/j.xpro.2023.102128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 01/09/2023] [Accepted: 02/03/2023] [Indexed: 02/22/2023] Open
Abstract
We present a protocol to generate high-quality fluorescently labeled DNA substrates that can be used for biochemical assays, including DNA-binding and nuclease activity assays. We describe polyacrylamide-gel-electrophoresis-based purification of DNA oligonucleotides, followed by annealing the oligonucleotides and purifying the annealed substrates using anion-exchange chromatography. This protocol circumvents the use of radioisotopes, which require training and dedicated equipment for safe handling and necessitate specialized waste disposal. This protocol is amenable to varying lengths of oligonucleotides and DNA substrates. For complete details on the use and execution of this protocol, please refer to Payliss and Tse et al. (2022).1.
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Affiliation(s)
| | - Hwa Young Yun
- Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Haley Doris Myskiw Wyatt
- Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada; Canada Research Chairs Program, Temerty Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada.
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3
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Song Q, Hu Y, Yin A, Wang H, Yin Q. DNA Holliday Junction: History, Regulation and Bioactivity. Int J Mol Sci 2022; 23:9730. [PMID: 36077130 PMCID: PMC9456528 DOI: 10.3390/ijms23179730] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 08/16/2022] [Accepted: 08/18/2022] [Indexed: 11/16/2022] Open
Abstract
DNA Holliday junction (HJ) is a four-way stranded DNA intermediate that formed in replication fork regression, homology-dependent repair and mitosis, performing a significant role in genomic stability. Failure to remove HJ can induce an acceptable replication fork stalling and DNA damage in normal cells, leading to a serious chromosomal aberration and even cell death in HJ nuclease-deficient tumor cells. Thus, HJ is becoming an attractive target in cancer therapy. However, the development of HJ-targeting ligand faces great challenges because of flexile cavities on the center of HJs. This review introduces the discovery history of HJ, elucidates the formation and dissociation procedures of HJ in corresponding bio-events, emphasizes the importance of prompt HJ-removing in genome stability, and summarizes recent advances in HJ-based ligand discovery. Our review indicate that target HJ is a promising approach in oncotherapy.
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Affiliation(s)
- Qinqin Song
- State/Key Laboratory of Microbial Technology, Shandong University, 72 Jimo Binhai Road, Qingdao 266237, China
| | - Yuemiao Hu
- Key Laboratory of Molecular Pharmacology and Drug Evaluation, Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, School of Pharmacy, Yantai University, 30 Qingquan Road, Yantai 264005, China
| | - Anqi Yin
- Key Laboratory of Molecular Pharmacology and Drug Evaluation, Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, School of Pharmacy, Yantai University, 30 Qingquan Road, Yantai 264005, China
| | - Hongbo Wang
- Key Laboratory of Molecular Pharmacology and Drug Evaluation, Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, School of Pharmacy, Yantai University, 30 Qingquan Road, Yantai 264005, China
| | - Qikun Yin
- Key Laboratory of Molecular Pharmacology and Drug Evaluation, Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, School of Pharmacy, Yantai University, 30 Qingquan Road, Yantai 264005, China
- Bohai Rim Advanced Research Institute for Drug Discovery, 198 Binhai East Road, Yantai 264005, China
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4
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Verma P, Kumari P, Negi S, Yadav G, Gaur V. Holliday junction resolution by At-HIGLE: an SLX1 lineage endonuclease from Arabidopsis thaliana with a novel in-built regulatory mechanism. Nucleic Acids Res 2022; 50:4630-4646. [PMID: 35412622 PMCID: PMC9071465 DOI: 10.1093/nar/gkac239] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 03/24/2022] [Accepted: 04/01/2022] [Indexed: 12/14/2022] Open
Abstract
Holliday junction is the key homologous recombination intermediate, resolved by structure-selective endonucleases (SSEs). SLX1 is the most promiscuous SSE of the GIY-YIG nuclease superfamily. In fungi and animals, SLX1 nuclease activity relies on a non-enzymatic partner, SLX4, but no SLX1-SLX4 like complex has ever been characterized in plants. Plants exhibit specialized DNA repair and recombination machinery. Based on sequence similarity with the GIY-YIG nuclease domain of SLX1 proteins from fungi and animals, At-HIGLE was identified to be a possible SLX1 like nuclease from plants. Here, we elucidated the crystal structure of the At-HIGLE nuclease domain from Arabidopsis thaliana, establishing it as a member of the SLX1-lineage of the GIY-YIG superfamily with structural changes in DNA interacting regions. We show that At-HIGLE can process branched-DNA molecules without an SLX4 like protein. Unlike fungal SLX1, At-HIGLE exists as a catalytically active homodimer capable of generating two coordinated nicks during HJ resolution. Truncating the extended C-terminal region of At-HIGLE increases its catalytic activity, changes the nicking pattern, and monomerizes At-HIGLE. Overall, we elucidated the first structure of a plant SLX1-lineage protein, showed its HJ resolving activity independent of any regulatory protein, and identified an in-built novel regulatory mechanism engaging its C-terminal region.
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Affiliation(s)
- Prabha Verma
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Poonam Kumari
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Shreya Negi
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Gitanjali Yadav
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Vineet Gaur
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi 110067, India
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5
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Raul B, Bhattacharjee O, Ghosh A, Upadhyay P, Tembhare K, Singh A, Shaheen T, Ghosh AK, Torres-Jerez I, Krom N, Clevenger J, Udvardi M, Scheffler BE, Ozias-Akins P, Sharma RD, Bandyopadhyay K, Gaur V, Kumar S, Sinharoy S. Microscopic and Transcriptomic Analyses of Dalbergoid Legume Peanut Reveal a Divergent Evolution Leading to Nod-Factor-Dependent Epidermal Crack-Entry and Terminal Bacteroid Differentiation. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2022; 35:131-145. [PMID: 34689599 DOI: 10.1094/mpmi-05-21-0122-r] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Root nodule symbiosis (RNS) is the pillar behind sustainable agriculture and plays a pivotal role in the environmental nitrogen cycle. Most of the genetic, molecular, and cell-biological knowledge on RNS comes from model legumes that exhibit a root-hair mode of bacterial infection, in contrast to the Dalbergoid legumes exhibiting crack-entry of rhizobia. As a step toward understanding this important group of legumes, we have combined microscopic analysis and temporal transcriptome to obtain a dynamic view of plant gene expression during Arachis hypogaea (peanut) nodule development. We generated comprehensive transcriptome data by mapping the reads to A. hypogaea, and two diploid progenitor genomes. Additionally, we performed BLAST searches to identify nodule-induced yet-to-be annotated peanut genes. Comparison between peanut, Medicago truncatula, Lotus japonicus, and Glycine max showed upregulation of 61 peanut orthologs among 111 tested known RNS-related genes, indicating conservation in mechanisms of nodule development among members of the Papilionoid family. Unlike model legumes, recruitment of class 1 phytoglobin-derived symbiotic hemoglobin (SymH) in peanut indicates diversification of oxygen-scavenging mechanisms in the Papilionoid family. Finally, the absence of cysteine-rich motif-1-containing nodule-specific cysteine-rich peptide (NCR) genes but the recruitment of defensin-like NCRs suggest a diverse molecular mechanism of terminal bacteroid differentiation. In summary, our work describes genetic conservation and diversification in legume-rhizobia symbiosis in the Papilionoid family, as well as among members of the Dalbergoid legumes.[Formula: see text] Copyright © 2022 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.
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Affiliation(s)
- Bikash Raul
- National Institute of Plant Genome Research (NIPGR), Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Oindrila Bhattacharjee
- National Institute of Plant Genome Research (NIPGR), Aruna Asaf Ali Marg, New Delhi 110067, India
- Amity University Haryana, Amity Education Valley, Manesar, Panchgaon, Haryana 122412, India
| | - Amit Ghosh
- National Institute of Plant Genome Research (NIPGR), Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Priya Upadhyay
- National Institute of Plant Genome Research (NIPGR), Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Kunal Tembhare
- National Institute of Plant Genome Research (NIPGR), Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Ajeet Singh
- National Institute of Plant Genome Research (NIPGR), Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Tarannum Shaheen
- National Institute of Plant Genome Research (NIPGR), Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Asim Kumar Ghosh
- National Institute of Plant Genome Research (NIPGR), Aruna Asaf Ali Marg, New Delhi 110067, India
| | | | - Nick Krom
- Noble Research Institute, 2510 Sam Noble Pkwy, Ardmore, OK 73401, U.S.A
| | - Josh Clevenger
- University of Georgia, Institute of Plant Breeding, Genetics and Genomics and Department of Horticulture, Tifton, GA 31793, U.S.A
| | - Michael Udvardi
- Noble Research Institute, 2510 Sam Noble Pkwy, Ardmore, OK 73401, U.S.A
| | - Brian E Scheffler
- United States Department of Agriculture-Agricultural Research Service Jamie Whitten Delta States Research Center (JWDSRC) Stoneville, JWDSRC, Bldg.1, Room 229, Experiment Station Road, PO Box 36, Stoneville, MS 38776-0036, U.S.A
| | - Peggy Ozias-Akins
- University of Georgia, Institute of Plant Breeding, Genetics and Genomics and Department of Horticulture, Tifton, GA 31793, U.S.A
| | - Ravi Datta Sharma
- Amity University Haryana, Amity Education Valley, Manesar, Panchgaon, Haryana 122412, India
| | - Kaustav Bandyopadhyay
- Amity University Haryana, Amity Education Valley, Manesar, Panchgaon, Haryana 122412, India
| | - Vineet Gaur
- National Institute of Plant Genome Research (NIPGR), Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Shailesh Kumar
- National Institute of Plant Genome Research (NIPGR), Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Senjuti Sinharoy
- National Institute of Plant Genome Research (NIPGR), Aruna Asaf Ali Marg, New Delhi 110067, India
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6
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Payliss BJ, Patel A, Sheppard AC, Wyatt HDM. Exploring the Structures and Functions of Macromolecular SLX4-Nuclease Complexes in Genome Stability. Front Genet 2021; 12:784167. [PMID: 34804132 PMCID: PMC8599992 DOI: 10.3389/fgene.2021.784167] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Accepted: 10/21/2021] [Indexed: 12/15/2022] Open
Abstract
All organisms depend on the ability of cells to accurately duplicate and segregate DNA into progeny. However, DNA is frequently damaged by factors in the environment and from within cells. One of the most dangerous lesions is a DNA double-strand break. Unrepaired breaks are a major driving force for genome instability. Cells contain sophisticated DNA repair networks to counteract the harmful effects of genotoxic agents, thus safeguarding genome integrity. Homologous recombination is a high-fidelity, template-dependent DNA repair pathway essential for the accurate repair of DNA nicks, gaps and double-strand breaks. Accurate homologous recombination depends on the ability of cells to remove branched DNA structures that form during repair, which is achieved through the opposing actions of helicases and structure-selective endonucleases. This review focuses on a structure-selective endonuclease called SLX1-SLX4 and the macromolecular endonuclease complexes that assemble on the SLX4 scaffold. First, we discuss recent developments that illuminate the structure and biochemical properties of this somewhat atypical structure-selective endonuclease. We then summarize the multifaceted roles that are fulfilled by human SLX1-SLX4 and its associated endonucleases in homologous recombination and genome stability. Finally, we discuss recent work on SLX4-binding proteins that may represent integral components of these macromolecular nuclease complexes, emphasizing the structure and function of a protein called SLX4IP.
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Affiliation(s)
- Brandon J Payliss
- Department of Biochemistry, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Ayushi Patel
- Department of Biochemistry, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Anneka C Sheppard
- Department of Biochemistry, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Haley D M Wyatt
- Department of Biochemistry, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada.,Canada Research Chairs Program, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
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7
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Xu X, Wang M, Sun J, Yu Z, Li G, Yang N, Xu RM. Structure specific DNA recognition by the SLX1-SLX4 endonuclease complex. Nucleic Acids Res 2021; 49:7740-7752. [PMID: 34181713 PMCID: PMC8287910 DOI: 10.1093/nar/gkab542] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2020] [Revised: 06/04/2021] [Accepted: 06/11/2021] [Indexed: 11/13/2022] Open
Abstract
The SLX1–SLX4 structure-specific endonuclease complex is involved in processing diverse DNA damage intermediates, including resolution of Holliday junctions, collapse of stalled replication forks and removal of DNA flaps. The nuclease subunit SLX1 is inactive on its own, but become activated upon binding to SLX4 via its conserved C-terminal domain (CCD). Yet, how the SLX1–SLX4 complex recognizes specific DNA structure and chooses cleavage sites remains unknown. Here we show, through a combination of structural, biochemical and computational analyses, that the SAP domain of SLX4 is critical for efficient and accurate processing of 5′-flap DNA. It binds the minor groove of DNA about one turn away from the flap junction, and the 5′-flap is implicated in binding the core domain of SLX1. This binding mode accounts for specific recognition of 5′-flap DNA and specification of cleavage site by the SLX1–SLX4 complex.
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Affiliation(s)
- Xiang Xu
- State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy and Key Laboratory of Medical Data Analysis and Statistical Research of Tianjin, Nankai University, Tianjin 300353, China.,National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Mingzhu Wang
- Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, Anhui, China
| | - Jixue Sun
- State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy and Key Laboratory of Medical Data Analysis and Statistical Research of Tianjin, Nankai University, Tianjin 300353, China
| | - Zhenyu Yu
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Guohong Li
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China.,School of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Na Yang
- State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy and Key Laboratory of Medical Data Analysis and Statistical Research of Tianjin, Nankai University, Tianjin 300353, China
| | - Rui-Ming Xu
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China.,School of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China
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8
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Young SJ, West SC. Coordinated roles of SLX4 and MutSβ in DNA repair and the maintenance of genome stability. Crit Rev Biochem Mol Biol 2021; 56:157-177. [PMID: 33596761 PMCID: PMC7610648 DOI: 10.1080/10409238.2021.1881433] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 01/06/2021] [Accepted: 01/22/2021] [Indexed: 12/14/2022]
Abstract
SLX4 provides a molecular scaffold for the assembly of multiple protein complexes required for the maintenance of genome stability. It is involved in the repair of DNA crosslinks, the resolution of recombination intermediates, the response to replication stress and the maintenance of telomere length. To carry out these diverse functions, SLX4 interacts with three structure-selective endonucleases, MUS81-EME1, SLX1 and XPF-ERCC1, as well as the telomere binding proteins TRF2, RTEL1 and SLX4IP. Recently, SLX4 was shown to interact with MutSβ, a heterodimeric protein involved in DNA mismatch repair, trinucleotide repeat instability, crosslink repair and recombination. Importantly, MutSβ promotes the pathogenic expansion of CAG/CTG trinucleotide repeats, which is causative of myotonic dystrophy and Huntington's disease. The colocalization and specific interaction of MutSβ with SLX4, together with their apparently overlapping functions, are suggestive of a common role in reactions that promote DNA maintenance and genome stability. This review will focus on the role of SLX4 in DNA repair, the interplay between MutSβ and SLX4, and detail how they cooperate to promote recombinational repair and DNA crosslink repair. Furthermore, we speculate that MutSβ and SLX4 may provide an alternative cellular mechanism that modulates trinucleotide instability.
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Affiliation(s)
- Sarah J Young
- DNA Recombination and Repair Laboratory, The Francis Crick Institute, London, UK
| | - Stephen C West
- DNA Recombination and Repair Laboratory, The Francis Crick Institute, London, UK
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9
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Young SJ, Sebald M, Shah Punatar R, Larin M, Masino L, Rodrigo-Brenni MC, Liang CC, West SC. MutSβ Stimulates Holliday Junction Resolution by the SMX Complex. Cell Rep 2020; 33:108289. [PMID: 33086055 DOI: 10.1016/j.celrep.2020.108289] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 09/02/2020] [Accepted: 09/29/2020] [Indexed: 12/20/2022] Open
Abstract
MutSα and MutSβ play important roles in DNA mismatch repair and are linked to inheritable cancers and degenerative disorders. Here, we show that MSH2 and MSH3, the two components of MutSβ, bind SLX4 protein, a scaffold for the assembly of the SLX1-SLX4-MUS81-EME1-XPF-ERCC1 (SMX) trinuclease complex. SMX promotes the resolution of Holliday junctions (HJs), which are intermediates in homologous recombinational repair. We find that MutSβ binds HJs and stimulates their resolution by SLX1-SLX4 or SMX in reactions dependent upon direct interactions between MutSβ and SLX4. In contrast, MutSα does not stimulate HJ resolution. MSH3-depleted cells exhibit reduced sister chromatid exchanges and elevated levels of homologous recombination ultrafine bridges (HR-UFBs) at mitosis, consistent with defects in the processing of recombination intermediates. These results demonstrate a role for MutSβ in addition to its established role in the pathogenic expansion of CAG/CTG trinucleotide repeats, which is causative of myotonic dystrophy and Huntington's disease.
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Affiliation(s)
- Sarah J Young
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Marie Sebald
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | | | - Meghan Larin
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Laura Masino
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | | | - Chih-Chao Liang
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Stephen C West
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK.
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10
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Verma P, Tandon R, Yadav G, Gaur V. Structural Aspects of DNA Repair and Recombination in Crop Improvement. Front Genet 2020; 11:574549. [PMID: 33024442 PMCID: PMC7516265 DOI: 10.3389/fgene.2020.574549] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2020] [Accepted: 08/25/2020] [Indexed: 12/18/2022] Open
Abstract
The adverse effects of global climate change combined with an exponentially increasing human population have put substantial constraints on agriculture, accelerating efforts towards ensuring food security for a sustainable future. Conventional plant breeding and modern technologies have led to the creation of plants with better traits and higher productivity. Most crop improvement approaches (conventional breeding, genome modification, and gene editing) primarily rely on DNA repair and recombination (DRR). Studying plant DRR can provide insights into designing new strategies or improvising the present techniques for crop improvement. Even though plants have evolved specialized DRR mechanisms compared to other eukaryotes, most of our insights about plant-DRRs remain rooted in studies conducted in animals. DRR mechanisms in plants include direct repair, nucleotide excision repair (NER), base excision repair (BER), mismatch repair (MMR), non-homologous end joining (NHEJ) and homologous recombination (HR). Although each DRR pathway acts on specific DNA damage, there is crosstalk between these. Considering the importance of DRR pathways as a tool in crop improvement, this review focuses on a general description of each DRR pathway, emphasizing on the structural aspects of key DRR proteins. The review highlights the gaps in our understanding and the importance of studying plant DRR in the context of crop improvement.
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Affiliation(s)
- Prabha Verma
- National Institute of Plant Genome Research, New Delhi, India
| | - Reetika Tandon
- National Institute of Plant Genome Research, New Delhi, India
| | - Gitanjali Yadav
- National Institute of Plant Genome Research, New Delhi, India
| | - Vineet Gaur
- National Institute of Plant Genome Research, New Delhi, India
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