1
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Schumacher MA, Singh RR, Salinas R. Structure of the E. coli nucleoid-associated protein YejK reveals a novel DNA binding clamp. Nucleic Acids Res 2024; 52:7354-7366. [PMID: 38832628 PMCID: PMC11229321 DOI: 10.1093/nar/gkae459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2024] [Revised: 05/02/2024] [Accepted: 05/15/2024] [Indexed: 06/05/2024] Open
Abstract
Nucleoid-associated proteins (NAPs) play central roles in bacterial chromosome organization and DNA processes. The Escherichia coli YejK protein is a highly abundant, yet poorly understood NAP. YejK proteins are conserved among Gram-negative bacteria but show no homology to any previously characterized DNA-binding protein. Hence, how YejK binds DNA is unknown. To gain insight into YejK structure and its DNA binding mechanism we performed biochemical and structural analyses on the E. coli YejK protein. Biochemical assays demonstrate that, unlike many NAPs, YejK does not show a preference for AT-rich DNA and binds non-sequence specifically. A crystal structure revealed YejK adopts a novel fold comprised of two domains. Strikingly, each of the domains harbors an extended arm that mediates dimerization, creating an asymmetric clamp with a 30 Å diameter pore. The lining of the pore is electropositive and mutagenesis combined with fluorescence polarization assays support DNA binding within the pore. Finally, our biochemical analyses on truncated YejK proteins suggest a mechanism for YejK clamp loading. Thus, these data reveal YejK contains a newly described DNA-binding motif that functions as a novel clamp.
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Affiliation(s)
- Maria A Schumacher
- Department of Biochemistry, 307 Research Dr., Box 3711, Duke University Medical Center, Durham, NC 27710, USA
| | - Rajiv R Singh
- Department of Biochemistry, 307 Research Dr., Box 3711, Duke University Medical Center, Durham, NC 27710, USA
| | - Raul Salinas
- Department of Biochemistry, 307 Research Dr., Box 3711, Duke University Medical Center, Durham, NC 27710, USA
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2
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Weyh M, Jokisch ML, Nguyen TA, Fottner M, Lang K. Deciphering functional roles of protein succinylation and glutarylation using genetic code expansion. Nat Chem 2024; 16:913-921. [PMID: 38531969 PMCID: PMC11164685 DOI: 10.1038/s41557-024-01500-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Accepted: 03/01/2024] [Indexed: 03/28/2024]
Abstract
Post-translational modifications (PTMs) dynamically regulate cellular processes. Lysine undergoes a range of acylations, including malonylation, succinylation (SucK) and glutarylation (GluK). These PTMs increase the size of the lysine side chain and reverse its charge from +1 to -1 under physiological conditions, probably impacting protein structure and function. To understand the functional roles of these PTMs, homogeneously modified proteins are required for biochemical studies. While the site-specific encoding of PTMs and their mimics via genetic code expansion has facilitated the characterization of the functional roles of many PTMs, negatively charged lysine acylations have defied this approach. Here we describe site-specific incorporation of SucK and GluK into proteins via temporarily masking their negative charge through thioester derivatives. We prepare succinylated and glutarylated bacterial and mammalian target proteins, including non-refoldable multidomain proteins. This allows us to study how succinylation and glutarylation impact enzymatic activity of metabolic enzymes and regulate protein-DNA and protein-protein interactions in biological processes from replication to ubiquitin signalling.
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Affiliation(s)
- Maria Weyh
- Laboratory for Organic Chemistry, Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich, Switzerland
| | - Marie-Lena Jokisch
- Laboratory for Organic Chemistry, Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich, Switzerland
| | - Tuan-Anh Nguyen
- Department of Chemistry, Laboratory for Synthetic Biochemistry, Technical University of Munich Institute for Advanced Study, Garching, Germany
- CeMM Research Center for Molecular Medicine, Austrian Academy of Sciences, Vienna, Austria
| | - Maximilian Fottner
- Laboratory for Organic Chemistry, Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich, Switzerland.
| | - Kathrin Lang
- Laboratory for Organic Chemistry, Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich, Switzerland.
- Department of Chemistry, Laboratory for Synthetic Biochemistry, Technical University of Munich Institute for Advanced Study, Garching, Germany.
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3
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Landeck JT, Pajak J, Norman EK, Sedivy EL, Kelch BA. Differences between bacteria and eukaryotes in clamp loader mechanism, a conserved process underlying DNA replication. J Biol Chem 2024; 300:107166. [PMID: 38490435 PMCID: PMC11044049 DOI: 10.1016/j.jbc.2024.107166] [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: 01/10/2024] [Revised: 02/23/2024] [Accepted: 03/01/2024] [Indexed: 03/17/2024] Open
Abstract
Clamp loaders are pentameric ATPases that place circular sliding clamps onto DNA, where they function in DNA replication and genome integrity. The central activity of a clamp loader is the opening of the ring-shaped sliding clamp and the subsequent binding to primer-template (p/t)-junctions. The general architecture of clamp loaders is conserved across all life, suggesting that their mechanism is retained. Recent structural studies of the eukaryotic clamp loader replication factor C (RFC) revealed that it functions using a crab-claw mechanism, where clamp opening is coupled to a massive conformational change in the loader. Here we investigate the clamp loading mechanism of the Escherichia coli clamp loader at high resolution using cryo-electron microscopy. We find that the E. coli clamp loader opens the clamp using a crab-claw motion at a single pivot point, whereas the eukaryotic RFC loader uses motions distributed across the complex. Furthermore, we find clamp opening occurs in multiple steps, starting with a partly open state with a spiral conformation, and proceeding to a wide open clamp in a surprising planar geometry. Finally, our structures in the presence of p/t-junctions illustrate how the clamp closes around p/t-junctions and how the clamp loader initiates release from the loaded clamp. Our results reveal mechanistic distinctions in a macromolecular machine that is conserved across all domains of life.
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Affiliation(s)
- Jacob T Landeck
- Department of Biochemistry and Molecular Biotechnology, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA
| | - Joshua Pajak
- Department of Biochemistry and Molecular Biotechnology, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA
| | - Emily K Norman
- Department of Biochemistry and Molecular Biotechnology, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA
| | - Emma L Sedivy
- Department of Biochemistry and Molecular Biotechnology, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA
| | - Brian A Kelch
- Department of Biochemistry and Molecular Biotechnology, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA.
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4
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Marcus K, Huang Y, Subramanian S, Gee CL, Gorday K, Ghaffari-Kashani S, Luo XR, Zheng L, O'Donnell M, Subramaniam S, Kuriyan J. Autoinhibition of a clamp-loader ATPase revealed by deep mutagenesis and cryo-EM. Nat Struct Mol Biol 2024; 31:424-435. [PMID: 38177685 PMCID: PMC10950542 DOI: 10.1038/s41594-023-01177-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 11/08/2023] [Indexed: 01/06/2024]
Abstract
Clamp loaders are AAA+ ATPases that facilitate high-speed DNA replication. In eukaryotic and bacteriophage clamp loaders, ATP hydrolysis requires interactions between aspartate residues in one protomer, present in conserved 'DEAD-box' motifs, and arginine residues in adjacent protomers. We show that functional defects resulting from a DEAD-box mutation in the T4 bacteriophage clamp loader can be compensated by widely distributed single mutations in the ATPase domain. Using cryo-EM, we discovered an unsuspected inactive conformation of the clamp loader, in which DNA binding is blocked and the catalytic sites are disassembled. Mutations that restore function map to regions of conformational change upon activation, suggesting that these mutations may increase DNA affinity by altering the energetic balance between inactive and active states. Our results show that there are extensive opportunities for evolution to improve catalytic efficiency when an inactive intermediate is involved.
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Affiliation(s)
- Kendra Marcus
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Yongjian Huang
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Subu Subramanian
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Christine L Gee
- Howard Hughes Medical Institute, University of California, Berkeley, CA, USA
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
| | - Kent Gorday
- Biophysics Graduate Group, University of California, Berkeley, CA, USA
| | - Sam Ghaffari-Kashani
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
| | - Xiao Ran Luo
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
| | - Lisa Zheng
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
| | - Michael O'Donnell
- Howard Hughes Medical Institute, The Rockefeller University, New York, NY, USA
| | - Sriram Subramaniam
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada
| | - John Kuriyan
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA.
- Department of Chemistry, Vanderbilt University, Nashville, TN, USA.
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5
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Landeck JT, Pajak J, Norman EK, Sedivy EL, Kelch BA. Differences in clamp loader mechanism between bacteria and eukaryotes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.30.569468. [PMID: 38076975 PMCID: PMC10705477 DOI: 10.1101/2023.11.30.569468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/18/2023]
Abstract
Clamp loaders are pentameric ATPases that place circular sliding clamps onto DNA, where they function in DNA replication and genome integrity. The central activity of a clamp loader is the opening of the ring-shaped sliding clamp, and the subsequent binding to primer-template (p/t)-junctions. The general architecture of clamp loaders is conserved across all life, suggesting that their mechanism is retained. Recent structural studies of the eukaryotic clamp loader Replication Factor C (RFC) revealed that it functions using a crab-claw mechanism, where clamp opening is coupled to a massive conformational change in the loader. Here we investigate the clamp loading mechanism of the E. coli clamp loader at high resolution using cryo-electron microscopy (cryo-EM). We find that the E. coli clamp loader opens the clamp using a crab-claw motion at a single pivot point, whereas the eukaryotic RFC loader uses motions distributed across the complex. Furthermore, we find clamp opening occurs in multiple steps, starting with a partly open state with a spiral conformation, and proceeding to a wide open clamp in a surprising planar geometry. Finally, our structures in the presence of p/t-junctions illustrate how clamp closes around p/t-junctions and how the clamp loader initiates release from the loaded clamp. Our results reveal mechanistic distinctions in a macromolecular machine that is conserved across all domains of life.
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Affiliation(s)
- Jacob T. Landeck
- Department of Biochemistry and Molecular Biotechnology, University of Massachusetts Chan Medical School, Worcester MA
| | - Joshua Pajak
- Department of Biochemistry and Molecular Biotechnology, University of Massachusetts Chan Medical School, Worcester MA
| | - Emily K. Norman
- Department of Biochemistry and Molecular Biotechnology, University of Massachusetts Chan Medical School, Worcester MA
| | - Emma L. Sedivy
- Department of Biochemistry and Molecular Biotechnology, University of Massachusetts Chan Medical School, Worcester MA
| | - Brian A. Kelch
- Department of Biochemistry and Molecular Biotechnology, University of Massachusetts Chan Medical School, Worcester MA
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Li S, Ge H, Li Y, Zhang K, Yu S, Cao H, Wang Y, Deng H, Li J, Dai J, Li LF, Luo Y, Sun Y, Geng Z, Dong Y, Zhang H, Qiu HJ. The E301R protein of African swine fever virus functions as a sliding clamp involved in viral genome replication. mBio 2023; 14:e0164523. [PMID: 37772878 PMCID: PMC10653895 DOI: 10.1128/mbio.01645-23] [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: 08/09/2023] [Accepted: 08/22/2023] [Indexed: 09/30/2023] Open
Abstract
IMPORTANCE Sliding clamp is a highly conserved protein in the evolution of prokaryotic and eukaryotic cells. The sliding clamp is required for genomic replication as a critical co-factor of DNA polymerases. However, the sliding clamp analogs in viruses remain largely unknown. We found that the ASFV E301R protein (pE301R) exhibited a sliding clamp-like structure and similar functions during ASFV replication. Interestingly, pE301R is assembled into a unique ring-shaped homotetramer distinct from sliding clamps or proliferating cell nuclear antigens (PCNAs) from other species. Notably, the E301R gene is required for viral life cycle, but the pE301R function can be partially restored by the porcine PCNA. This study not only highlights the functional role of the ASFV pE301R as a viral sliding clamp analog, but also facilitates the dissection of the complex replication mechanism of ASFV, which provides novel clues for developing antivirals against ASF.
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Affiliation(s)
- Su Li
- State Key Laboratory for Animal Disease Control and Prevention, National African Swine Fever Para-Reference Laboratory, National High-Containment Facilities for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Hailiang Ge
- State Key Laboratory for Animal Disease Control and Prevention, National African Swine Fever Para-Reference Laboratory, National High-Containment Facilities for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
- College of Animal Sciences, Yangtze University, Jingzhou, China
| | - Yanhua Li
- Multidiscipline Research Center, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, China
| | - Kehui Zhang
- State Key Laboratory for Animal Disease Control and Prevention, National African Swine Fever Para-Reference Laboratory, National High-Containment Facilities for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Shaoxiong Yu
- State Key Laboratory for Animal Disease Control and Prevention, National African Swine Fever Para-Reference Laboratory, National High-Containment Facilities for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Hongwei Cao
- State Key Laboratory for Animal Disease Control and Prevention, National African Swine Fever Para-Reference Laboratory, National High-Containment Facilities for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Yanjin Wang
- State Key Laboratory for Animal Disease Control and Prevention, National African Swine Fever Para-Reference Laboratory, National High-Containment Facilities for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Hao Deng
- State Key Laboratory for Animal Disease Control and Prevention, National African Swine Fever Para-Reference Laboratory, National High-Containment Facilities for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Jiaqi Li
- State Key Laboratory for Animal Disease Control and Prevention, National African Swine Fever Para-Reference Laboratory, National High-Containment Facilities for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Jingwen Dai
- State Key Laboratory for Animal Disease Control and Prevention, National African Swine Fever Para-Reference Laboratory, National High-Containment Facilities for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Lian-Feng Li
- State Key Laboratory for Animal Disease Control and Prevention, National African Swine Fever Para-Reference Laboratory, National High-Containment Facilities for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Yuzi Luo
- State Key Laboratory for Animal Disease Control and Prevention, National African Swine Fever Para-Reference Laboratory, National High-Containment Facilities for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Yuan Sun
- State Key Laboratory for Animal Disease Control and Prevention, National African Swine Fever Para-Reference Laboratory, National High-Containment Facilities for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Zhi Geng
- Multidiscipline Research Center, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, China
| | - Yuhui Dong
- Multidiscipline Research Center, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, China
| | - Heng Zhang
- Multidiscipline Research Center, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, China
| | - Hua-Ji Qiu
- State Key Laboratory for Animal Disease Control and Prevention, National African Swine Fever Para-Reference Laboratory, National High-Containment Facilities for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
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7
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Shao Z, Yang J, Gao Y, Zhang Y, Zhao X, Shao Q, Zhang W, Cao C, Liu H, Gan J. Structural and functional studies of PCNA from African swine fever virus. J Virol 2023; 97:e0074823. [PMID: 37534905 PMCID: PMC10506467 DOI: 10.1128/jvi.00748-23] [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: 05/19/2023] [Accepted: 06/16/2023] [Indexed: 08/04/2023] Open
Abstract
Proliferating cell nuclear antigen (PCNA) belongs to the DNA sliding clamp family. Via interacting with various partner proteins, PCNA plays critical roles in DNA replication, DNA repair, chromatin assembly, epigenetic inheritance, chromatin remodeling, and many other fundamental biological processes. Although PCNA and PCNA-interacting partner networks are conserved across species, PCNA of a given species is rarely functional in heterologous systems, emphasizing the importance of more representative PCNA studies. Here, we report two crystal structures of PCNA from African swine fever virus (ASFV), which is the only member of the Asfarviridae family. Compared to the eukaryotic and archaeal PCNAs and the sliding clamp structural homologs from other viruses, AsfvPCNA possesses unique sequences and/or conformations at several regions, such as the J-loop, interdomain-connecting loop (IDCL), P-loop, and C-tail, which are involved in partner recognition or modification of sliding clamps. In addition to double-stranded DNA binding, we also demonstrate that AsfvPCNA can modestly enhance the ligation activity of the AsfvLIG protein. The unique structural features of AsfvPCNA can serve as a potential target for the development of ASFV-specific inhibitors and help combat the deadly virus. IMPORTANCE Two high-resolution crystal structures of African swine fever virus proliferating cell nuclear antigen (AsfvPCNA) are presented here. Structural comparison revealed that AsfvPCNA is unique at several regions, such as the J-loop, the interdomain-connecting loop linker, and the P-loop, which may play important roles in ASFV-specific partner selection of AsfvPCNA. Unlike eukaryotic and archaeal PCNAs, AsfvPCNA possesses high double-stranded DNA-binding affinity. Besides DNA binding, AsfvPCNA can also modestly enhance the ligation activity of the AsfvLIG protein, which is essential for the replication and repair of ASFV genome. The unique structural features make AsfvPCNA a potential target for drug development, which will help combat the deadly virus.
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Affiliation(s)
- Zhiwei Shao
- Shanghai Public Health Clinical Center, State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China
| | - Jie Yang
- Shanghai Public Health Clinical Center, State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China
| | - Yanqing Gao
- Shanghai Public Health Clinical Center, State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China
| | - Yixi Zhang
- Shanghai Public Health Clinical Center, State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China
| | - Xin Zhao
- Shanghai Public Health Clinical Center, State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China
| | - Qiyuan Shao
- Shanghai Public Health Clinical Center, State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China
| | - Weizhen Zhang
- Shanghai Public Health Clinical Center, State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China
| | - Chulei Cao
- Shanghai Public Health Clinical Center, State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China
| | - Hehua Liu
- Shanghai Public Health Clinical Center, State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China
| | - Jianhua Gan
- Shanghai Public Health Clinical Center, State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China
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DNA binding by the Rad9A subunit of the Rad9-Rad1-Hus1 complex. PLoS One 2022; 17:e0272645. [PMID: 35939452 PMCID: PMC9359528 DOI: 10.1371/journal.pone.0272645] [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: 02/14/2022] [Accepted: 07/22/2022] [Indexed: 11/19/2022] Open
Abstract
The Rad9-Rad1-Hus1 checkpoint clamp activates the DNA damage response and promotes DNA repair. DNA loading on the central channel of the Rad9-Rad1-Hus1 complex is required to execute its biological functions. Because Rad9A has the highest DNA affinity among the three subunits, we determined the domains and functional residues of human Rad9A that are critical for DNA interaction. The N-terminal globular domain (residues 1–133) had 3.7-fold better DNA binding affinity than the C-terminal globular domain (residues 134–266) of Rad9A1-266. Rad9A1-266 binds DNA 16-, 60-, and 30-fold better than Rad9A1-133, Rad9A134-266, and Rad9A94-266, respectively, indicating that different regions cooperatively contribute to DNA binding. We show that basic residues including K11, K15, R22, K78, K220, and R223 are important for DNA binding. The reductions on DNA binding of Ala substituted mutants of these basic residues show synergistic effect and are dependent on their residential Rad9A deletion constructs. Interestingly, deletion of a loop (residues 160–163) of Rad9A94-266 weakens DNA binding activity by 4.1-fold as compared to wild-type (WT) Rad9A94-266. Cellular sensitivity to genotoxin of rad9A knockout cells is restored by expressing WT-Rad9Afull. However, rad9A knockout cells expressing Rad9A mutants defective in DNA binding are more sensitive to H2O2 as compared to cells expressing WT-Rad9Afull. Only the rad9A knockout cells expressing loop-deleted Rad9A mutant are more sensitive to hydroxyurea than cells expressing WT-Rad9A. In addition, Rad9A-DNA interaction is required for DNA damage signaling activation. Our results indicate that DNA association by Rad9A is critical for maintaining cell viability and checkpoint activation under stress.
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Gaubitz C, Liu X, Pajak J, Stone NP, Hayes JA, Demo G, Kelch BA. Cryo-EM structures reveal high-resolution mechanism of a DNA polymerase sliding clamp loader. eLife 2022; 11:74175. [PMID: 35179493 PMCID: PMC8893722 DOI: 10.7554/elife.74175] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 02/01/2022] [Indexed: 11/13/2022] Open
Abstract
Sliding clamps are ring-shaped protein complexes that are integral to the DNA replication machinery of all life. Sliding clamps are opened and installed onto DNA by clamp loader AAA+ ATPase complexes. However, how a clamp loader opens and closes the sliding clamp around DNA is still unknown. Here, we describe structures of the Saccharomyces cerevisiae clamp loader Replication Factor C (RFC) bound to its cognate sliding clamp Proliferating Cell Nuclear Antigen (PCNA) en route to successful loading. RFC first binds to PCNA in a dynamic, closed conformation that blocks both ATPase activity and DNA binding. RFC then opens the PCNA ring through a large-scale ‘crab-claw’ expansion of both RFC and PCNA that explains how RFC prefers initial binding of PCNA over DNA. Next, the open RFC:PCNA complex binds DNA and interrogates the primer-template junction using a surprising base-flipping mechanism. Our structures indicate that initial PCNA opening and subsequent closure around DNA do not require ATP hydrolysis, but are driven by binding energy. ATP hydrolysis, which is necessary for RFC release, is triggered by interactions with both PCNA and DNA, explaining RFC’s switch-like ATPase activity. Our work reveals how a AAA+ machine undergoes dramatic conformational changes for achieving binding preference and substrate remodeling.
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Affiliation(s)
- Christl Gaubitz
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, United States
| | - Xingchen Liu
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, United States
| | - Joshua Pajak
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, United States
| | - Nicholas P Stone
- Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, United States
| | - Janelle A Hayes
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, United States
| | - Gabriel Demo
- Central European Institute of Technology - Masaryk University, Brno, Czech Republic
| | - Brian A Kelch
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, United States
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10
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Shen S, Davidson GA, Yang K, Zhuang Z. Photo-activatable Ub-PCNA probes reveal new structural features of the Saccharomyces cerevisiae Polη/PCNA complex. Nucleic Acids Res 2021; 49:9374-9388. [PMID: 34390346 PMCID: PMC8450101 DOI: 10.1093/nar/gkab646] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 07/02/2021] [Accepted: 08/12/2021] [Indexed: 12/05/2022] Open
Abstract
The Y-family DNA polymerase η (Polη) is critical for the synthesis past damaged DNA nucleotides in yeast through translesion DNA synthesis (TLS). TLS is initiated by monoubiquitination of proliferating cell nuclear antigen (PCNA) and the subsequent recruitment of TLS polymerases. Although individual structures of the Polη catalytic core and PCNA have been solved, a high-resolution structure of the complex of Polη/PCNA or Polη/monoubiquitinated PCNA (Ub-PCNA) still remains elusive, partly due to the disordered Polη C-terminal region and the flexibility of ubiquitin on PCNA. To circumvent these obstacles and obtain structural insights into this important TLS polymerase complex, we developed photo-activatable PCNA and Ub-PCNA probes containing a p-benzoyl-L-phenylalanine (pBpa) crosslinker at selected positions on PCNA. By photo-crosslinking the probes with full-length Polη, specific crosslinking sites were identified following tryptic digestion and tandem mass spectrometry analysis. We discovered direct interactions of the Polη catalytic core and its C-terminal region with both sides of the PCNA ring. Model building using the crosslinking site information as a restraint revealed multiple conformations of Polη in the polymerase complex. Availability of the photo-activatable PCNA and Ub-PCNA probes will also facilitate investigations into other PCNA-containing complexes important for DNA replication, repair and damage tolerance.
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Affiliation(s)
- Siqi Shen
- Department of Chemistry and Biochemistry, University of Delaware, 214A Drake Hall, Newark, DE 19716, USA
| | - Gregory A Davidson
- Department of Chemistry and Biochemistry, University of Delaware, 214A Drake Hall, Newark, DE 19716, USA
| | - Kun Yang
- Department of Chemistry and Biochemistry, University of Delaware, 214A Drake Hall, Newark, DE 19716, USA
| | - Zhihao Zhuang
- Department of Chemistry and Biochemistry, University of Delaware, 214A Drake Hall, Newark, DE 19716, USA
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11
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Strand discrimination in DNA mismatch repair. DNA Repair (Amst) 2021; 105:103161. [PMID: 34171627 DOI: 10.1016/j.dnarep.2021.103161] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 06/15/2021] [Accepted: 06/16/2021] [Indexed: 11/24/2022]
Abstract
DNA mismatch repair (MMR) corrects non-Watson-Crick basepairs generated by replication errors, recombination intermediates, and some forms of chemical damage to DNA. In MutS and MutL homolog-dependent MMR, damaged bases do not identify the error-containing daughter strand that must be excised and resynthesized. In organisms like Escherichia coli that use methyl-directed MMR, transient undermethylation identifies the daughter strand. For other organisms, growing in vitro and in vivo evidence suggest that strand discrimination is mediated by DNA replication-associated daughter strand nicks that direct asymmetric loading of the replicative clamp (the β-clamp in bacteria and the proliferating cell nuclear antigen, PCNA, in eukaryotes). Structural modeling suggests that replicative clamps mediate strand specificity either through the ability of MutL homologs to recognize the fixed orientation of the daughter strand relative to one face of the replicative clamps or through parental strand-specific diffusion of replicative clamps on DNA, which places the daughter strand in the MutL homolog endonuclease active site. Finally, identification of bacteria that appear to lack strand discrimination mediated by a replicative clamp and a pre-existing nick suggest that other strand discrimination mechanisms exist or that these organisms perform MMR by generating a double-stranded DNA break intermediate, which may be analogous to NucS-mediated MMR.
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12
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Subramanian S, Gorday K, Marcus K, Orellana MR, Ren P, Luo XR, O'Donnell ME, Kuriyan J. Allosteric communication in DNA polymerase clamp loaders relies on a critical hydrogen-bonded junction. eLife 2021; 10:e66181. [PMID: 33847559 PMCID: PMC8121543 DOI: 10.7554/elife.66181] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Accepted: 04/03/2021] [Indexed: 02/06/2023] Open
Abstract
Clamp loaders are AAA+ ATPases that load sliding clamps onto DNA. We mapped the mutational sensitivity of the T4 bacteriophage sliding clamp and clamp loader by deep mutagenesis, and found that residues not involved in catalysis or binding display remarkable tolerance to mutation. An exception is a glutamine residue in the AAA+ module (Gln 118) that is not located at a catalytic or interfacial site. Gln 118 forms a hydrogen-bonded junction in a helical unit that we term the central coupler, because it connects the catalytic centers to DNA and the sliding clamp. A suppressor mutation indicates that hydrogen bonding in the junction is important, and molecular dynamics simulations reveal that it maintains rigidity in the central coupler. The glutamine-mediated junction is preserved in diverse AAA+ ATPases, suggesting that a connected network of hydrogen bonds that links ATP molecules is an essential aspect of allosteric communication in these proteins.
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Affiliation(s)
- Subu Subramanian
- Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
- California Institute for Quantitative Biosciences (QB3), University of California, BerkeleyBerkeleyUnited States
- Howard Hughes Medical Institute, University of California, BerkeleyBerkeleyUnited States
| | - Kent Gorday
- Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
- California Institute for Quantitative Biosciences (QB3), University of California, BerkeleyBerkeleyUnited States
- Biophysics Graduate Group, University of California, BerkeleyBerkeleyUnited States
| | - Kendra Marcus
- Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
- California Institute for Quantitative Biosciences (QB3), University of California, BerkeleyBerkeleyUnited States
| | - Matthew R Orellana
- Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
- California Institute for Quantitative Biosciences (QB3), University of California, BerkeleyBerkeleyUnited States
| | - Peter Ren
- Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
- California Institute for Quantitative Biosciences (QB3), University of California, BerkeleyBerkeleyUnited States
| | - Xiao Ran Luo
- Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
- California Institute for Quantitative Biosciences (QB3), University of California, BerkeleyBerkeleyUnited States
| | - Michael E O'Donnell
- Howard Hughes Medical Institute, Rockefeller UniversityNew YorkUnited States
| | - John Kuriyan
- Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
- California Institute for Quantitative Biosciences (QB3), University of California, BerkeleyBerkeleyUnited States
- Howard Hughes Medical Institute, University of California, BerkeleyBerkeleyUnited States
- Department of Chemistry, University of California, BerkeleyBerkeleyUnited States
- Physical Biosciences Division, Lawrence Berkeley National LaboratoryBerkeleyUnited States
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13
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Sundaram R, Manohar K, Patel SK, Acharya N, Vasudevan D. Structural analyses of PCNA from the fungal pathogen Candida albicans identify three regions with species-specific conformations. FEBS Lett 2021; 595:1328-1349. [PMID: 33544878 DOI: 10.1002/1873-3468.14055] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Revised: 01/29/2021] [Accepted: 02/01/2021] [Indexed: 01/11/2023]
Abstract
An assembly of multiprotein complexes achieves chromosomal DNA replication at the replication fork. In eukaryotes, proliferating cell nuclear antigen (PCNA) plays a vital role in the assembly of multiprotein complexes at the replication fork and is essential for cell viability. PCNA from several organisms, including Saccharomyces cerevisiae, has been structurally characterised. However, the structural analyses of PCNA from fungal pathogens are limited. Recently, we have reported that PCNA from the opportunistic fungal pathogen Candida albicans complements the essential functions of ScPCNA in S. cerevisiae. Still, it only partially rescues the loss of ScPCNA when the yeast cells are under genotoxic stress. To understand this further, herein, we have determined the crystal structure of CaPCNA and compared that with the existing structures of other fungal and human PCNA. Our comparative structural and in-solution small-angle X-ray scattering (SAXS) analyses reveal that CaPCNA forms a stable homotrimer, both in crystal and in solution. It displays noticeable structural alterations in the oligomerisation interface, P-loop and hydrophobic pocket regions, suggesting its differential function in a heterologous system and avenues for developing specific therapeutics. DATABASES: The PDB and SASBDB accession codes for CaPCNA are 7BUP and SASDHQ9, respectively.
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Affiliation(s)
- Rajivgandhi Sundaram
- Laboratory of Macromolecular Crystallography, Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, India.,Manipal Academy of Higher Education, India
| | - Kodavati Manohar
- Laboratory of Genomic Instability and Diseases, Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, India
| | - Shraddheya Kumar Patel
- Laboratory of Genomic Instability and Diseases, Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, India
| | - Narottam Acharya
- Laboratory of Genomic Instability and Diseases, Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, India
| | - Dileep Vasudevan
- Laboratory of Macromolecular Crystallography, Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, India
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14
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Li H, Zheng F, O'Donnell M. Water skating: How polymerase sliding clamps move on DNA. FEBS J 2021; 288:7256-7262. [PMID: 33523561 DOI: 10.1111/febs.15740] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Revised: 01/19/2021] [Accepted: 01/24/2021] [Indexed: 11/30/2022]
Abstract
Polymerase sliding clamps are ring-shaped proteins that encircle duplex DNA and hold polymerases to DNA for high processivity during synthesis. The crystal structure of clamp-DNA complex reveals that the DNA is highly tilted through the clamp with extensive interaction with the clamp inner surface. In contrast to the tilted clamp-DNA interaction without DNA polymerases, recent structures of replicative polymerases of bacteria, eukaryotes, and archaea that are bound to the clamp and DNA show that the polymerase positions DNA straight through the clamp without direct protein-DNA contacts. Instead, the clamp-to-DNA interaction is mediated by one or two layers of water. Hence, clamps 'water skate' on DNA during function with replicative polymerases from all domains of life, providing a nearly frictionless bearing for fast and processive DNA synthesis.
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Affiliation(s)
- Huilin Li
- Department of Structural Biology, Van Andel Institute, Grand Rapids, MI, USA
| | - Fengwei Zheng
- Department of Structural Biology, Van Andel Institute, Grand Rapids, MI, USA
| | - Mike O'Donnell
- DNA Replication Laboratory, The Rockefeller University, New York, NY, USA.,HHMI, The Rockefeller University, New York, NY, USA
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15
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Structure of eukaryotic DNA polymerase δ bound to the PCNA clamp while encircling DNA. Proc Natl Acad Sci U S A 2020; 117:30344-30353. [PMID: 33203675 PMCID: PMC7720213 DOI: 10.1073/pnas.2017637117] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The structure of the eukaryotic chromosomal replicase, DNA polymerase (Pol) δ, was determined in complex with its cognate proliferating cell nuclear antigen (PCNA) sliding clamp on primed DNA. The results show that the Pol3 catalytic subunit binds atop the PCNA ring, and the two regulatory subunits of Pol δ, Pol31, and Pol32, are positioned off to the side of the Pol3 clamp. The catalytic Pol3 binds DNA and PCNA such as to thread the DNA straight through the circular PCNA clamp. Considering the large diameter of the PCNA clamp, there is room for water between DNA and the inner walls of PCNA, indicating the clamp “waterskates” on DNA during function with polymerase. The DNA polymerase (Pol) δ of Saccharomyces cerevisiae (S.c.) is composed of the catalytic subunit Pol3 along with two regulatory subunits, Pol31 and Pol32. Pol δ binds to proliferating cell nuclear antigen (PCNA) and functions in genome replication, repair, and recombination. Unique among DNA polymerases, the Pol3 catalytic subunit contains a 4Fe-4S cluster that may sense the cellular redox state. Here we report the 3.2-Å cryo-EM structure of S.c. Pol δ in complex with primed DNA, an incoming ddTTP, and the PCNA clamp. Unexpectedly, Pol δ binds only one subunit of the PCNA trimer. This singular yet extensive interaction holds DNA such that the 2-nm-wide DNA threads through the center of the 3-nm interior channel of the clamp without directly contacting the protein. Thus, a water-mediated clamp and DNA interface enables the PCNA clamp to “waterskate” along the duplex with minimum drag. Pol31 and Pol32 are positioned off to the side of the catalytic Pol3-PCNA-DNA axis. We show here that Pol31-Pol32 binds single-stranded DNA that we propose underlies polymerase recycling during lagging strand synthesis, in analogy to Escherichia coli replicase. Interestingly, the 4Fe-4S cluster in the C-terminal CysB domain of Pol3 forms the central interface to Pol31-Pol32, and this strategic location may explain the regulation of the oxidation state on Pol δ activity, possibly useful during cellular oxidative stress. Importantly, human cancer and other disease mutations map to nearly every domain of Pol3, suggesting that all aspects of Pol δ replication are important to human health and disease.
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16
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Reply to: "Does PCNA diffusion on DNA follow a rotation-coupled translation mechanism?". Nat Commun 2020; 11:4999. [PMID: 33020489 PMCID: PMC7536410 DOI: 10.1038/s41467-020-18856-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Accepted: 09/17/2020] [Indexed: 11/08/2022] Open
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17
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González-Magaña A, Blanco FJ. Human PCNA Structure, Function and Interactions. Biomolecules 2020; 10:biom10040570. [PMID: 32276417 PMCID: PMC7225939 DOI: 10.3390/biom10040570] [Citation(s) in RCA: 132] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 04/01/2020] [Accepted: 04/03/2020] [Indexed: 12/13/2022] Open
Abstract
Proliferating cell nuclear antigen (PCNA) is an essential factor in DNA replication and repair. It forms a homotrimeric ring that embraces the DNA and slides along it, anchoring DNA polymerases and other DNA editing enzymes. It also interacts with regulatory proteins through a sequence motif known as PCNA Interacting Protein box (PIP-box). We here review the latest contributions to knowledge regarding the structure-function relationships in human PCNA, particularly the mechanism of sliding, and of the molecular recognition of canonical and non-canonical PIP motifs. The unique binding mode of the oncogene p15 is described in detail, and the implications of the recently discovered structure of PCNA bound to polymerase δ are discussed. The study of the post-translational modifications of PCNA and its partners may yield therapeutic opportunities in cancer treatment, in addition to illuminating the way PCNA coordinates the dynamic exchange of its many partners in DNA replication and repair.
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Affiliation(s)
- Amaia González-Magaña
- CIC bioGUNE, Bizkaia Science and Technology Park, bld 800, 48160 Derio, Bizkaia, Spain;
| | - Francisco J. Blanco
- CIC bioGUNE, Bizkaia Science and Technology Park, bld 800, 48160 Derio, Bizkaia, Spain;
- IKERBASQUE, Basque Foundation for Science, Maria Diaz de Haro 3, 6 solairua, 48013 Bilbao, Bizkaia, Spain
- Correspondence:
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18
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Madru C, Henneke G, Raia P, Hugonneau-Beaufet I, Pehau-Arnaudet G, England P, Lindahl E, Delarue M, Carroni M, Sauguet L. Structural basis for the increased processivity of D-family DNA polymerases in complex with PCNA. Nat Commun 2020; 11:1591. [PMID: 32221299 PMCID: PMC7101311 DOI: 10.1038/s41467-020-15392-9] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Accepted: 03/05/2020] [Indexed: 11/09/2022] Open
Abstract
Replicative DNA polymerases (DNAPs) have evolved the ability to copy the genome with high processivity and fidelity. In Eukarya and Archaea, the processivity of replicative DNAPs is greatly enhanced by its binding to the proliferative cell nuclear antigen (PCNA) that encircles the DNA. We determined the cryo-EM structure of the DNA-bound PolD–PCNA complex from Pyrococcus abyssi at 3.77 Å. Using an integrative structural biology approach — combining cryo-EM, X-ray crystallography, protein–protein interaction measurements, and activity assays — we describe the molecular basis for the interaction and cooperativity between a replicative DNAP and PCNA. PolD recruits PCNA via a complex mechanism, which requires two different PIP-boxes. We infer that the second PIP-box, which is shared with the eukaryotic Polα replicative DNAP, plays a dual role in binding either PCNA or primase, and could be a master switch between an initiation and a processive phase during replication. Replicative DNA polymerases (DNAPs) have evolved the ability to copy the genome with high processivity and fidelity. Here, the authors present a cryo-EM structure of the DNA-bound PolD–PCNA complex from Pyrococcus abyssi to reveal the molecular basis for the interaction and cooperativity between a replicative DNAP and PCNA.
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Affiliation(s)
- Clément Madru
- Unit of Structural Dynamics of Macromolecules, Institut Pasteur and CNRS UMR 3528, Paris, France
| | - Ghislaine Henneke
- CNRS, Ifremer, Université de Brest, Laboratoire de Microbiologie des Environnements Extrêmes, Plouzané, France
| | - Pierre Raia
- Unit of Structural Dynamics of Macromolecules, Institut Pasteur and CNRS UMR 3528, Paris, France.,Sorbonne Université, École Doctorale Complexité du Vivant (ED515), Paris, France
| | - Inès Hugonneau-Beaufet
- Unit of Structural Dynamics of Macromolecules, Institut Pasteur and CNRS UMR 3528, Paris, France
| | | | - Patrick England
- Molecular Biophysics Platform, C2RT, Institut Pasteur, CNRS UMR 3528, Paris, France
| | - Erik Lindahl
- Department of Biochemistry and Biophysics, Science for Life Laboratory, Stockholm University, Stockholm, Sweden.,Department of Applied Physics, KTH Royal Institute of Technology, Stockholm, Sweden
| | - Marc Delarue
- Unit of Structural Dynamics of Macromolecules, Institut Pasteur and CNRS UMR 3528, Paris, France
| | - Marta Carroni
- Department of Biochemistry and Biophysics, Science for Life Laboratory, Stockholm University, Stockholm, Sweden.
| | - Ludovic Sauguet
- Unit of Structural Dynamics of Macromolecules, Institut Pasteur and CNRS UMR 3528, Paris, France.
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19
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Hayes JA, Hilbert BJ, Gaubitz C, Stone NP, Kelch BA. A thermophilic phage uses a small terminase protein with a fixed helix-turn-helix geometry. J Biol Chem 2020; 295:3783-3793. [PMID: 32014998 DOI: 10.1074/jbc.ra119.012224] [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: 12/16/2019] [Revised: 01/30/2020] [Indexed: 11/06/2022] Open
Abstract
Tailed bacteriophages use a DNA-packaging motor to encapsulate their genome during viral particle assembly. The small terminase (TerS) component of this DNA-packaging machinery acts as a molecular matchmaker that recognizes both the viral genome and the main motor component, the large terminase (TerL). However, how TerS binds DNA and the TerL protein remains unclear. Here we identified gp83 of the thermophilic bacteriophage P74-26 as the TerS protein. We found that TerSP76-26 oligomerizes into a nonamer that binds DNA, stimulates TerL ATPase activity, and inhibits TerL nuclease activity. A cryo-EM structure of TerSP76-26 revealed that it forms a ring with a wide central pore and radially arrayed helix-turn-helix domains. The structure further showed that these helix-turn-helix domains, which are thought to bind DNA by wrapping the double helix around the ring, are rigidly held in an orientation distinct from that seen in other TerS proteins. This rigid arrangement of the putative DNA-binding domain imposed strong constraints on how TerSP76-26 can bind DNA. Finally, the TerSP76-26 structure lacked the conserved C-terminal β-barrel domain used by other TerS proteins for binding TerL. This suggests that a well-ordered C-terminal β-barrel domain is not required for TerSP76-26 to carry out its matchmaking function. Our work highlights a thermophilic system for studying the role of small terminase proteins in viral maturation and presents the structure of TerSP76-26, revealing key differences between this thermophilic phage and its mesophilic counterparts.
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Affiliation(s)
- Janelle A Hayes
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts 01655
| | - Brendan J Hilbert
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts 01655
| | - Christl Gaubitz
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts 01655
| | - Nicholas P Stone
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts 01655
| | - Brian A Kelch
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts 01655
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20
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Paul Solomon Devakumar LJ, Gaubitz C, Lundblad V, Kelch BA, Kubota T. Effective mismatch repair depends on timely control of PCNA retention on DNA by the Elg1 complex. Nucleic Acids Res 2020; 47:6826-6841. [PMID: 31114918 PMCID: PMC6648347 DOI: 10.1093/nar/gkz441] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 05/06/2019] [Accepted: 05/09/2019] [Indexed: 11/14/2022] Open
Abstract
Proliferating cell nuclear antigen (PCNA) is a sliding clamp that acts as a central co-ordinator for mismatch repair (MMR) as well as DNA replication. Loss of Elg1, the major subunit of the PCNA unloader complex, causes over-accumulation of PCNA on DNA and also increases mutation rate, but it has been unclear if the two effects are linked. Here we show that timely removal of PCNA from DNA by the Elg1 complex is important to prevent mutations. Although premature unloading of PCNA generally increases mutation rate, the mutator phenotype of elg1Δ is attenuated by PCNA mutants PCNA-R14E and PCNA-D150E that spontaneously fall off DNA. In contrast, the elg1Δ mutator phenotype is exacerbated by PCNA mutants that accumulate on DNA due to enhanced electrostatic PCNA–DNA interactions. Epistasis analysis suggests that PCNA over-accumulation on DNA interferes with both MMR and MMR-independent process(es). In elg1Δ, over-retained PCNA hyper-recruits the Msh2–Msh6 mismatch recognition complex through its PCNA-interacting peptide motif, causing accumulation of MMR intermediates. Our results suggest that PCNA retention controlled by the Elg1 complex is critical for efficient MMR: PCNA needs to be on DNA long enough to enable MMR, but if it is retained too long it interferes with downstream repair steps.
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Affiliation(s)
- Lovely Jael Paul Solomon Devakumar
- Institute of Medical Sciences, School of Medicine, Medical Sciences & Nutrition, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, Scotland, UK
| | - Christl Gaubitz
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | | | - Brian A Kelch
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Takashi Kubota
- Institute of Medical Sciences, School of Medicine, Medical Sciences & Nutrition, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, Scotland, UK
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21
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He Y, Wang Z, Hu Y, Yi X, Wu L, Cao Z, Wang J. Sensitive and selective monitoring of the DNA damage-induced intracellular p21 protein and unraveling the role of the p21 protein in DNA repair and cell apoptosis by surface plasmon resonance. Analyst 2020; 145:3697-3704. [DOI: 10.1039/c9an02464f] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Sensitive and selective monitoring of DNA damage-induced intracellular p21 protein is proposed using surface plasmon resonance. The method serves as a viable means for unraveling the role of p21 protein in DNA repair and cell apoptosis.
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Affiliation(s)
- Yuhan He
- Hunan Provincial Key Laboratory of Micro & Nano Materials Interface Science
- College of Chemistry and Chemical Engineering
- Central South University
- Changsha
- P. R. China 410083
| | - Zixiao Wang
- Hunan Provincial Key Laboratory of Micro & Nano Materials Interface Science
- College of Chemistry and Chemical Engineering
- Central South University
- Changsha
- P. R. China 410083
| | - Yuqing Hu
- Hunan Provincial Key Laboratory of Micro & Nano Materials Interface Science
- College of Chemistry and Chemical Engineering
- Central South University
- Changsha
- P. R. China 410083
| | - Xinyao Yi
- Hunan Provincial Key Laboratory of Micro & Nano Materials Interface Science
- College of Chemistry and Chemical Engineering
- Central South University
- Changsha
- P. R. China 410083
| | - Ling Wu
- Hunan Provincial Key Laboratory of Micro & Nano Materials Interface Science
- College of Chemistry and Chemical Engineering
- Central South University
- Changsha
- P. R. China 410083
| | - Zhong Cao
- Hunan Provincial Key Laboratory of Materials Protection for Electric Power and Transportation
- School of Chemistry and Biological Engineering
- Changsha University of Science and Technology
- Changsha
- P. R. China 410114
| | - Jianxiu Wang
- Hunan Provincial Key Laboratory of Micro & Nano Materials Interface Science
- College of Chemistry and Chemical Engineering
- Central South University
- Changsha
- P. R. China 410083
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22
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Daitchman D, Greenblatt HM, Levy Y. Diffusion of ring-shaped proteins along DNA: case study of sliding clamps. Nucleic Acids Res 2019; 46:5935-5949. [PMID: 29860305 PMCID: PMC6158715 DOI: 10.1093/nar/gky436] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Accepted: 05/08/2018] [Indexed: 12/13/2022] Open
Abstract
Several DNA-binding proteins, such as topoisomerases, helicases and sliding clamps, have a toroidal (i.e. ring) shape that topologically traps DNA, with this quality being essential to their function. Many DNA-binding proteins that function, for example, as transcription factors or enzymes were shown to be able to diffuse linearly (i.e. slide) along DNA during the search for their target binding sites. The protein's sliding properties and ability to search DNA, which often also involves hopping and dissociation, are expected to be different when it encircles the DNA. In this study, we explored the linear diffusion of four ring-shaped proteins of very similar structure: three sliding clamps (PCNA, β-clamp, and the gp45) and the 9-1-1 protein, with a particular focus on PCNA. Coarse-grained molecular dynamics simulations were performed to decipher the sliding mechanism adopted by these ring-shaped proteins and to determine how the molecular properties of the inner and outer ring govern its search speed. We designed in silico variants to dissect the contributions of ring geometry and electrostatics to the sliding speed of ring-shaped proteins along DNA. We found that the toroidal proteins diffuse when they are tilted relative to the DNA axis and able to rotate during translocation, but that coupling between rotation and translocation is quite weak. Their diffusion speed is affected by the shape of the inner ring and, to a lesser extent, by its electrostatic properties. However, breaking the symmetry of the electrostatic potential can result in deviation of the DNA from the center of the ring and cause slower linear diffusion. The findings are discussed in light of earlier computational and experimental studies on the sliding of clamps.
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Affiliation(s)
- Dina Daitchman
- Department of Structural Biology, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Harry M Greenblatt
- Department of Structural Biology, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Yaakov Levy
- Department of Structural Biology, Weizmann Institute of Science, Rehovot 76100, Israel
- To whom correspondence should be addressed. Tel: +972 8 9344587;
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23
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De March M, Barrera-Vilarmau S, Crespan E, Mentegari E, Merino N, Gonzalez-Magaña A, Romano-Moreno M, Maga G, Crehuet R, Onesti S, Blanco FJ, De Biasio A. p15PAF binding to PCNA modulates the DNA sliding surface. Nucleic Acids Res 2019; 46:9816-9828. [PMID: 30102405 PMCID: PMC6182140 DOI: 10.1093/nar/gky723] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 07/31/2018] [Indexed: 12/15/2022] Open
Abstract
p15PAF is an oncogenic intrinsically disordered protein that regulates DNA replication and lesion bypass by interacting with the human sliding clamp PCNA. In the absence of DNA, p15PAF traverses the PCNA ring via an extended PIP-box that contacts the sliding surface. Here, we probed the atomic-scale structure of p15PAF–PCNA–DNA ternary complexes. Crystallography and MD simulations show that, when p15PAF occupies two subunits of the PCNA homotrimer, DNA within the ring channel binds the unoccupied subunit. The structure of PCNA-bound p15PAF in the absence and presence of DNA is invariant, and solution NMR confirms that DNA does not displace p15PAF from the ring wall. Thus, p15PAF reduces the available sliding surfaces of PCNA, and may function as a belt that fastens the DNA to the clamp during synthesis by the replicative polymerase (pol δ). This constraint, however, may need to be released for efficient DNA lesion bypass by the translesion synthesis polymerase (pol η). Accordingly, our biochemical data show that p15PAF impairs primer synthesis by pol η–PCNA holoenzyme against both damaged and normal DNA templates. In light of our findings, we discuss the possible mechanistic roles of p15PAF in DNA replication and suppression of DNA lesion bypass.
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Affiliation(s)
- Matteo De March
- Structural Biology Laboratory, Elettra-Sincrotrone Trieste S.C.p.A., Trieste 34149, Italy
| | - Susana Barrera-Vilarmau
- Institute of Advanced Chemistry of Catalonia (IQAC), CSIC, Jordi Girona 18-26, 08034, Barcelona, Spain
| | - Emmanuele Crespan
- Institute of Molecular Genetics, IGM-CNR, via Abbiategrasso 207, 27100 Pavia, Italy
| | - Elisa Mentegari
- Institute of Molecular Genetics, IGM-CNR, via Abbiategrasso 207, 27100 Pavia, Italy
| | - Nekane Merino
- CIC bioGUNE, Parque Tecnológico de Bizkaia Edificio 800, 48160 Derio, Spain
| | | | | | - Giovanni Maga
- Institute of Molecular Genetics, IGM-CNR, via Abbiategrasso 207, 27100 Pavia, Italy
| | - Ramon Crehuet
- Institute of Advanced Chemistry of Catalonia (IQAC), CSIC, Jordi Girona 18-26, 08034, Barcelona, Spain
| | - Silvia Onesti
- Structural Biology Laboratory, Elettra-Sincrotrone Trieste S.C.p.A., Trieste 34149, Italy
| | - Francisco J Blanco
- CIC bioGUNE, Parque Tecnológico de Bizkaia Edificio 800, 48160 Derio, Spain.,IKERBASQUE, Basque Foundation for Science, Bilbao, Spain
| | - Alfredo De Biasio
- Structural Biology Laboratory, Elettra-Sincrotrone Trieste S.C.p.A., Trieste 34149, Italy.,Leicester Institute of Structural & Chemical Biology and Department of Molecular & Cell Biology, University of Leicester, Lancaster Rd, Leicester LE1 7HB, UK
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24
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Jiang Q, Zhang W, Liu C, Lin Y, Wu Q, Dai J. Dissecting PCNA function with a systematically designed mutant library in yeast. J Genet Genomics 2019; 46:301-313. [PMID: 31281030 DOI: 10.1016/j.jgg.2019.03.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2018] [Revised: 02/27/2019] [Accepted: 03/07/2019] [Indexed: 11/26/2022]
Abstract
Proliferating cell nuclear antigen (PCNA), encoded by POL30 in Saccharomyces cerevisiae, is a key component of DNA metabolism. Here, a library consisting of 304 PCNA mutants was designed and constructed to probe the contribution of each residue to the biological function of PCNA. Five regions with elevated sensitivity to DNA damaging reagents were identified using high-throughput phenotype screening. Using a series of genetic and biochemical analyses, we demonstrated that one particular mutant, K168A, has defects in the DNA damage tolerance (DDT) pathway by disrupting the interaction between PCNA and Rad5. Subsequent domain analysis showed that the PCNA-Rad5 interaction is a prerequisite for the function of Rad5 in DDT. Our study not only provides a resource in the form of a library of versatile mutants to study the functions of PCNA, but also reveals a key residue on PCNA (K168) which highlights the importance of the PCNA-Rad5 interaction in the template switching (TS) pathway.
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Affiliation(s)
- Qingwen Jiang
- Center for Synthetic and Systems Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China; Shenzhen Key Laboratory of Synthetic Genomics and Center for Synthetic Genomics, Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Weimin Zhang
- Center for Synthetic and Systems Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China; Shenzhen Key Laboratory of Synthetic Genomics and Center for Synthetic Genomics, Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Chenghao Liu
- Center for Synthetic and Systems Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Yicong Lin
- Center for Synthetic and Systems Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China; Shenzhen Key Laboratory of Synthetic Genomics and Center for Synthetic Genomics, Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Qingyu Wu
- Center for Synthetic and Systems Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Junbiao Dai
- Center for Synthetic and Systems Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China; Shenzhen Key Laboratory of Synthetic Genomics and Center for Synthetic Genomics, Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China.
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25
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Raia P, Carroni M, Henry E, Pehau-Arnaudet G, Brûlé S, Béguin P, Henneke G, Lindahl E, Delarue M, Sauguet L. Structure of the DP1-DP2 PolD complex bound with DNA and its implications for the evolutionary history of DNA and RNA polymerases. PLoS Biol 2019; 17:e3000122. [PMID: 30657780 PMCID: PMC6355029 DOI: 10.1371/journal.pbio.3000122] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 01/31/2019] [Accepted: 01/10/2019] [Indexed: 02/01/2023] Open
Abstract
PolD is an archaeal replicative DNA polymerase (DNAP) made of a proofreading exonuclease subunit (DP1) and a larger polymerase catalytic subunit (DP2). Recently, we reported the individual crystal structures of the DP1 and DP2 catalytic cores, thereby revealing that PolD is an atypical DNAP that has all functional properties of a replicative DNAP but with the catalytic core of an RNA polymerase (RNAP). We now report the DNA-bound cryo-electron microscopy (cryo-EM) structure of the heterodimeric DP1-DP2 PolD complex from Pyrococcus abyssi, revealing a unique DNA-binding site. Comparison of PolD and RNAPs extends their structural similarities and brings to light the minimal catalytic core shared by all cellular transcriptases. Finally, elucidating the structure of the PolD DP1-DP2 interface, which is conserved in all eukaryotic replicative DNAPs, clarifies their evolutionary relationships with PolD and sheds light on the domain acquisition and exchange mechanism that occurred during the evolution of the eukaryotic replisome.
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Affiliation(s)
- Pierre Raia
- Unit of Structural Dynamics of Macromolecules, Pasteur Institute and CNRS UMR 3528, Paris, France
- Sorbonne Université, Ecole Doctorale Complexité du Vivant (ED515), Paris, France
| | - Marta Carroni
- Science for Life Laboratory, Department of Biochemistry and Biophysics, Stockholm University, Sweden
| | - Etienne Henry
- CNRS, IFREMER, Univ Brest, Laboratoire de Microbiologie des Environnements Extrêmes, Plouzané, France
| | | | - Sébastien Brûlé
- Molecular Biophysics Platform, Pasteur Institute, C2RT and CNRS UMR 3528, Paris, France
| | - Pierre Béguin
- Unit of Molecular Biology of Gene in Extremophiles, Pasteur Institute, Paris, France
| | - Ghislaine Henneke
- IFREMER, CNRS, Univ Brest, Laboratoire de Microbiologie des Environnements Extrêmes, Plouzané, France
| | - Erik Lindahl
- Science for Life Laboratory, Department of Biochemistry and Biophysics, Stockholm University, Sweden
| | - Marc Delarue
- Unit of Structural Dynamics of Macromolecules, Pasteur Institute and CNRS UMR 3528, Paris, France
| | - Ludovic Sauguet
- Unit of Structural Dynamics of Macromolecules, Pasteur Institute and CNRS UMR 3528, Paris, France
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26
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Laponogov I, Pan XS, Veselkov DA, Skamrova GB, Umrekar TR, Fisher LM, Sanderson MR. Trapping of the transport-segment DNA by the ATPase domains of a type II topoisomerase. Nat Commun 2018; 9:2579. [PMID: 29968711 PMCID: PMC6030046 DOI: 10.1038/s41467-018-05005-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Accepted: 05/25/2018] [Indexed: 11/09/2022] Open
Abstract
Type II topoisomerases alter DNA topology to control DNA supercoiling and chromosome segregation and are targets of clinically important anti-infective and anticancer therapeutics. They act as ATP-operated clamps to trap a DNA helix and transport it through a transient break in a second DNA. Here, we present the first X-ray crystal structure solved at 2.83 Å of a closed clamp complete with trapped T-segment DNA obtained by co-crystallizing the ATPase domain of S. pneumoniae topoisomerase IV with a nonhydrolyzable ATP analogue and 14-mer duplex DNA. The ATPase dimer forms a 22 Å protein hole occupied by the kinked DNA bound asymmetrically through positively charged residues lining the hole, and whose mutagenesis impacts the DNA decatenation, DNA relaxation and DNA-dependent ATPase activities of topo IV. These results and a side-bound DNA-ParE structure help explain how the T-segment DNA is captured and transported by a type II topoisomerase, and reveal a new enzyme-DNA interface for drug discovery.
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Affiliation(s)
- Ivan Laponogov
- Randall Centre for Cell and Molecular Biophysics, 3rd Floor New Hunt's House, Faculty of Life Sciences and Medicine, King's College London, London, SE1 1UL, UK.,Molecular and Clinical Sciences Research Institute, St. George's, University of London, Cranmer Terrace, London, SW17 0RE, UK.,Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, Sir Alexander Fleming Building, London, SW7 2AZ, UK
| | - Xiao-Su Pan
- Molecular and Clinical Sciences Research Institute, St. George's, University of London, Cranmer Terrace, London, SW17 0RE, UK
| | - Dennis A Veselkov
- Randall Centre for Cell and Molecular Biophysics, 3rd Floor New Hunt's House, Faculty of Life Sciences and Medicine, King's College London, London, SE1 1UL, UK
| | - Galyna B Skamrova
- Randall Centre for Cell and Molecular Biophysics, 3rd Floor New Hunt's House, Faculty of Life Sciences and Medicine, King's College London, London, SE1 1UL, UK
| | - Trishant R Umrekar
- Randall Centre for Cell and Molecular Biophysics, 3rd Floor New Hunt's House, Faculty of Life Sciences and Medicine, King's College London, London, SE1 1UL, UK.,The Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck College, University of London, Malet St., London, WC1E 7HX, UK
| | - L Mark Fisher
- Molecular and Clinical Sciences Research Institute, St. George's, University of London, Cranmer Terrace, London, SW17 0RE, UK.
| | - Mark R Sanderson
- Randall Centre for Cell and Molecular Biophysics, 3rd Floor New Hunt's House, Faculty of Life Sciences and Medicine, King's College London, London, SE1 1UL, UK.
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27
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Hashimoto H, Hishiki A, Hara K, Kikuchi S. Structural basis for the molecular interactions in DNA damage tolerances. Biophys Physicobiol 2017; 14:199-205. [PMID: 29362705 PMCID: PMC5773155 DOI: 10.2142/biophysico.14.0_199] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Accepted: 11/18/2017] [Indexed: 01/01/2023] Open
Abstract
DNA damage tolerance (DDT) is a cell function to avoid replication arrest by DNA damage during DNA replication. DDT includes two pathways, translesion DNA synthesis (TLS) and template-switched DNA synthesis (TS). DDT is regulated by ubiquitination of proliferating cell nuclear antigen that binds to double-stranded DNA and functions as scaffold protein for DNA metabolism. TLS is transient DNA synthesis using damaged DNA as a template by error-prone DNA polymerases termed TLS polymerases specialized for DNA damage. TS, in which one newly synthesized strand is utilized as an undamaged template for replication by replicative polymerases, is error-free process. Thus, DDT is not inherently a repair pathway. DDT is a mechanism to tolerate DNA damage, giving priority to DNA synthesis and enabling finish of DNA replication for cell survival and genome stability. DDT is associated with cancer development and thus is of great interest in drug discovery for cancer therapy. This review article describes recent progress in structural studies on protein-protein and protein-DNA complexes involved in TLS and TS, providing the molecular mechanisms of interactions in DDT.
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Affiliation(s)
- Hiroshi Hashimoto
- School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka 422-8002, Japan
| | - Asami Hishiki
- School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka 422-8002, Japan
| | - Kodai Hara
- School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka 422-8002, Japan
| | - Sotaro Kikuchi
- School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka 422-8002, Japan.,Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX 75390
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28
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Li H, Sandhu M, Malkas LH, Hickey RJ, Vaidehi N. How Does the Proliferating Cell Nuclear Antigen Modulate Binding Specificity to Multiple Partner Proteins? J Chem Inf Model 2017; 57:3011-3021. [DOI: 10.1021/acs.jcim.7b00171] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Hubert Li
- Department
of Molecular Immunology and ‡Department of Molecular Medicine, Beckman Research Institute of the City of Hope, 1500 East Duarte Road, Duarte, California 91010, United States
| | - Manbir Sandhu
- Department
of Molecular Immunology and ‡Department of Molecular Medicine, Beckman Research Institute of the City of Hope, 1500 East Duarte Road, Duarte, California 91010, United States
| | - Linda H. Malkas
- Department
of Molecular Immunology and ‡Department of Molecular Medicine, Beckman Research Institute of the City of Hope, 1500 East Duarte Road, Duarte, California 91010, United States
| | - Robert J. Hickey
- Department
of Molecular Immunology and ‡Department of Molecular Medicine, Beckman Research Institute of the City of Hope, 1500 East Duarte Road, Duarte, California 91010, United States
| | - Nagarajan Vaidehi
- Department
of Molecular Immunology and ‡Department of Molecular Medicine, Beckman Research Institute of the City of Hope, 1500 East Duarte Road, Duarte, California 91010, United States
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29
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De March M, De Biasio A. The dark side of the ring: role of the DNA sliding surface of PCNA. Crit Rev Biochem Mol Biol 2017; 52:663-673. [DOI: 10.1080/10409238.2017.1364218] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Matteo De March
- Structural Biology Laboratory, Elettra-Sincrotrone Trieste S.C.p.A, Trieste, Italy
| | - Alfredo De Biasio
- Structural Biology Laboratory, Elettra-Sincrotrone Trieste S.C.p.A, Trieste, Italy
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30
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Spampinato CP. Protecting DNA from errors and damage: an overview of DNA repair mechanisms in plants compared to mammals. Cell Mol Life Sci 2017; 74:1693-1709. [PMID: 27999897 PMCID: PMC11107726 DOI: 10.1007/s00018-016-2436-2] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Revised: 12/01/2016] [Accepted: 12/05/2016] [Indexed: 01/10/2023]
Abstract
The genome integrity of all organisms is constantly threatened by replication errors and DNA damage arising from endogenous and exogenous sources. Such base pair anomalies must be accurately repaired to prevent mutagenesis and/or lethality. Thus, it is not surprising that cells have evolved multiple and partially overlapping DNA repair pathways to correct specific types of DNA errors and lesions. Great progress in unraveling these repair mechanisms at the molecular level has been made by several talented researchers, among them Tomas Lindahl, Aziz Sancar, and Paul Modrich, all three Nobel laureates in Chemistry for 2015. Much of this knowledge comes from studies performed in bacteria, yeast, and mammals and has impacted research in plant systems. Two plant features should be mentioned. Plants differ from higher eukaryotes in that they lack a reserve germline and cannot avoid environmental stresses. Therefore, plants have evolved different strategies to sustain genome fidelity through generations and continuous exposure to genotoxic stresses. These strategies include the presence of unique or multiple paralogous genes with partially overlapping DNA repair activities. Yet, in spite (or because) of these differences, plants, especially Arabidopsis thaliana, can be used as a model organism for functional studies. Some advantages of this model system are worth mentioning: short life cycle, availability of both homozygous and heterozygous lines for many genes, plant transformation techniques, tissue culture methods and reporter systems for gene expression and function studies. Here, I provide a current understanding of DNA repair genes in plants, with a special focus on A. thaliana. It is expected that this review will be a valuable resource for future functional studies in the DNA repair field, both in plants and animals.
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Affiliation(s)
- Claudia P Spampinato
- Facultad de Ciencias Bioquímicas y Farmacéuticas, Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI), Universidad Nacional de Rosario, Suipacha 531, 2000, Rosario, Argentina.
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31
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Yoda T, Tanabe M, Tsuji T, Yoda T, Ishino S, Shirai T, Ishino Y, Takeyama H, Nishida H. Exonuclease processivity of archaeal replicative DNA polymerase in association with PCNA is expedited by mismatches in DNA. Sci Rep 2017; 7:44582. [PMID: 28300173 PMCID: PMC5353730 DOI: 10.1038/srep44582] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Accepted: 02/10/2017] [Indexed: 01/01/2023] Open
Abstract
Family B DNA polymerases comprise polymerase and 3′ −>5′ exonuclease domains, and detect a mismatch in a newly synthesized strand to remove it in cooperation with Proliferating cell nuclear antigen (PCNA), which encircles the DNA to provide a molecular platform for efficient protein–protein and protein–DNA interactions during DNA replication and repair. Once the repair is completed, the enzyme must stop the exonucleolytic process and switch to the polymerase mode. However, the cue to stop the degradation is unclear. We constructed several PCNA mutants and found that the exonuclease reaction was enhanced in the mutants lacking the conserved basic patch, located on the inside surface of PCNA. These mutants may mimic the Pol/PCNA complex processing the mismatched DNA, in which PCNA cannot interact rigidly with the irregularly distributed phosphate groups outside the dsDNA. Indeed, the exonuclease reaction with the wild type PCNA was facilitated by mismatched DNA substrates. PCNA may suppress the exonuclease reaction after the removal of the mismatched nucleotide. PCNA seems to act as a “brake” that stops the exonuclease mode of the DNA polymerase after the removal of a mismatched nucleotide from the substrate DNA, for the prompt switch to the DNA polymerase mode.
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Affiliation(s)
- Takuya Yoda
- Department of Life Science and Medical Bioscience, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Maiko Tanabe
- Hitachi, Ltd. Research &Development Group, 1-280 Higashi-koigakubo, Kokubunji, Tokyo 185-8601, Japan
| | - Toshiyuki Tsuji
- Department of Computer Bioscience, Nagahama Institute of Bio-Science and Technology, 1266 Tamura-cho, Nagahama, Shiga 526-0829, Japan
| | - Takao Yoda
- Department of Computer Bioscience, Nagahama Institute of Bio-Science and Technology, 1266 Tamura-cho, Nagahama, Shiga 526-0829, Japan
| | - Sonoko Ishino
- Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka, Fukuoka 812-8581, Japan
| | - Tsuyoshi Shirai
- Department of Computer Bioscience, Nagahama Institute of Bio-Science and Technology, 1266 Tamura-cho, Nagahama, Shiga 526-0829, Japan
| | - Yoshizumi Ishino
- Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka, Fukuoka 812-8581, Japan
| | - Haruko Takeyama
- Department of Life Science and Medical Bioscience, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Hirokazu Nishida
- Hitachi, Ltd. Research &Development Group, 1-280 Higashi-koigakubo, Kokubunji, Tokyo 185-8601, Japan
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32
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Kelch BA. Review: The lord of the rings: Structure and mechanism of the sliding clamp loader. Biopolymers 2017; 105:532-46. [PMID: 26918303 DOI: 10.1002/bip.22827] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Revised: 02/15/2016] [Accepted: 02/23/2016] [Indexed: 12/15/2022]
Abstract
Sliding clamps are ring-shaped polymerase processivity factors that act as master regulators of cellular replication by coordinating multiple functions on DNA to ensure faithful transmission of genetic and epigenetic information. Dedicated AAA+ ATPase machines called clamp loaders actively place clamps on DNA, thereby governing clamp function by controlling when and where clamps are used. Clamp loaders are also important model systems for understanding the basic principles of AAA+ mechanism and function. After nearly 30 years of study, the ATP-dependent mechanism of opening and loading of clamps is now becoming clear. Here I review the structural and mechanistic aspects of the clamp loading process, as well as comment on questions that will be addressed by future studies. © 2016 Wiley Periodicals, Inc. Biopolymers 105: 532-546, 2016.
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Affiliation(s)
- Brian A Kelch
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA, 01605
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33
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Billon P, Côté J. Novel mechanism of PCNA control through acetylation of its sliding surface. Mol Cell Oncol 2017; 4:e1279724. [PMID: 28401185 DOI: 10.1080/23723556.2017.1279724] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Revised: 01/03/2017] [Accepted: 01/04/2017] [Indexed: 10/20/2022]
Abstract
Recent findings revealed a new unexpected regulatory mechanism that controls the proliferating cell nuclear antigen (PCNA). Multiple positively-charged lysine residues located on the ring inner surface are neutralized by acetylation and required for cellular resistance to Desoxyribonucleic acid (DNA) damage. Here, we summarize the key observations, discuss implications, and perspectives linked to cancer, as well as challenges for future work.
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Affiliation(s)
- Pierre Billon
- Department of Genetics and Development, Herbert Irving Comprehensive Cancer Center, Columbia University Medical Center , New York, NY, USA
| | - Jacques Côté
- St-Patrick Research Group in Basic Oncology, Laval University Cancer Research Center, Centre de Recherche du CHU de Québec-Axe Oncologie , Quebec City, QC, Canada
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34
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De March M, Merino N, Barrera-Vilarmau S, Crehuet R, Onesti S, Blanco FJ, De Biasio A. Structural basis of human PCNA sliding on DNA. Nat Commun 2017; 8:13935. [PMID: 28071730 PMCID: PMC5234079 DOI: 10.1038/ncomms13935] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Accepted: 11/14/2016] [Indexed: 02/06/2023] Open
Abstract
Sliding clamps encircle DNA and tether polymerases and other factors to the genomic template. However, the molecular mechanism of clamp sliding on DNA is unknown. Using crystallography, NMR and molecular dynamics simulations, here we show that the human clamp PCNA recognizes DNA through a double patch of basic residues within the ring channel, arranged in a right-hand spiral that matches the pitch of B-DNA. We propose that PCNA slides by tracking the DNA backbone via a ‘cogwheel' mechanism based on short-lived polar interactions, which keep the orientation of the clamp invariant relative to DNA. Mutation of residues at the PCNA–DNA interface has been shown to impair the initiation of DNA synthesis by polymerase δ (pol δ). Therefore, our findings suggest that a clamp correctly oriented on DNA is necessary for the assembly of a replication-competent PCNA-pol δ holoenzyme. DNA sliding clamps are ring-shaped proteins that encircle DNA and harbour polymerases and other factors that promote processive DNA replication. Here the authors use X-ray crystallography, NMR and MD simulations to propose a model for a PCNA sliding mechanism that relies on short-lived polar interactions.
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Affiliation(s)
- Matteo De March
- Structural Biology Laboratory, Elettra-Sincrotrone Trieste S.C.p.A., 34149 Trieste, Italy
| | - Nekane Merino
- CIC bioGUNE, Parque Tecnologico de Bizkaia Edificio 800, 48160 Derio, Spain
| | - Susana Barrera-Vilarmau
- Institute of Advanced Chemistry of Catalonia (IQAC), CSIC, Jordi Girona 18-26, 08034 Barcelona, Spain
| | - Ramon Crehuet
- Institute of Advanced Chemistry of Catalonia (IQAC), CSIC, Jordi Girona 18-26, 08034 Barcelona, Spain
| | - Silvia Onesti
- Structural Biology Laboratory, Elettra-Sincrotrone Trieste S.C.p.A., 34149 Trieste, Italy
| | - Francisco J Blanco
- CIC bioGUNE, Parque Tecnologico de Bizkaia Edificio 800, 48160 Derio, Spain.,IKERBASQUE, Basque Foundation for Science, Bilbao 48013, Spain
| | - Alfredo De Biasio
- Structural Biology Laboratory, Elettra-Sincrotrone Trieste S.C.p.A., 34149 Trieste, Italy
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35
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Rychkov GN, Ilatovskiy AV, Nazarov IB, Shvetsov AV, Lebedev DV, Konev AY, Isaev-Ivanov VV, Onufriev AV. Partially Assembled Nucleosome Structures at Atomic Detail. Biophys J 2016; 112:460-472. [PMID: 28038734 DOI: 10.1016/j.bpj.2016.10.041] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 10/06/2016] [Accepted: 10/28/2016] [Indexed: 11/29/2022] Open
Abstract
The evidence is now overwhelming that partially assembled nucleosome states (PANS) are as important as the canonical nucleosome structure for the understanding of how accessibility to genomic DNA is regulated in cells. We use a combination of molecular dynamics simulation and atomic force microscopy to deliver, in atomic detail, structural models of three key PANS: the hexasome (H2A·H2B)·(H3·H4)2, the tetrasome (H3·H4)2, and the disome (H3·H4). Despite fluctuations of the conformation of the free DNA in these structures, regions of protected DNA in close contact with the histone core remain stable, thus establishing the basis for the understanding of the role of PANS in DNA accessibility regulation. On average, the length of protected DNA in each structure is roughly 18 basepairs per histone protein. Atomistically detailed PANS are used to explain experimental observations; specifically, we discuss interpretation of atomic force microscopy, Förster resonance energy transfer, and small-angle x-ray scattering data obtained under conditions when PANS are expected to exist. Further, we suggest an alternative interpretation of a recent genome-wide study of DNA protection in active chromatin of fruit fly, leading to a conclusion that the three PANS are present in actively transcribing regions in a substantial amount. The presence of PANS may not only be a consequence, but also a prerequisite for fast transcription in vivo.
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Affiliation(s)
- Georgy N Rychkov
- Division of Molecular and Radiation Biophysics, B.P. Konstantinov Petersburg Nuclear Physics Institute, National Research Center "Kurchatov Institute", Orlova Roscha, Gatchina, Leningrad District, Russia; Institute of Physics, Nanotechnology and Telecommunications, NRU Peter the Great St. Petersburg Polytechnic University, St. Petersburg, Russia
| | - Andrey V Ilatovskiy
- Division of Molecular and Radiation Biophysics, B.P. Konstantinov Petersburg Nuclear Physics Institute, National Research Center "Kurchatov Institute", Orlova Roscha, Gatchina, Leningrad District, Russia; Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, California
| | - Igor B Nazarov
- Institute of Cytology, Russian Academy of Sciences, St. Petersburg, Russia
| | - Alexey V Shvetsov
- Division of Molecular and Radiation Biophysics, B.P. Konstantinov Petersburg Nuclear Physics Institute, National Research Center "Kurchatov Institute", Orlova Roscha, Gatchina, Leningrad District, Russia; Institute of Applied Mathematics and Mechanics, NRU Peter the Great St. Petersburg Polytechnic University, St. Petersburg, Russia
| | - Dmitry V Lebedev
- Division of Molecular and Radiation Biophysics, B.P. Konstantinov Petersburg Nuclear Physics Institute, National Research Center "Kurchatov Institute", Orlova Roscha, Gatchina, Leningrad District, Russia
| | - Alexander Y Konev
- Division of Molecular and Radiation Biophysics, B.P. Konstantinov Petersburg Nuclear Physics Institute, National Research Center "Kurchatov Institute", Orlova Roscha, Gatchina, Leningrad District, Russia
| | - Vladimir V Isaev-Ivanov
- Division of Molecular and Radiation Biophysics, B.P. Konstantinov Petersburg Nuclear Physics Institute, National Research Center "Kurchatov Institute", Orlova Roscha, Gatchina, Leningrad District, Russia
| | - Alexey V Onufriev
- Departments of Computer Science and Physics, Virginia Tech, Blacksburg, Virginia.
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36
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Billon P, Li J, Lambert JP, Chen Y, Tremblay V, Brunzelle JS, Gingras AC, Verreault A, Sugiyama T, Couture JF, Côté J. Acetylation of PCNA Sliding Surface by Eco1 Promotes Genome Stability through Homologous Recombination. Mol Cell 2016; 65:78-90. [PMID: 27916662 DOI: 10.1016/j.molcel.2016.10.033] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Revised: 10/09/2016] [Accepted: 10/24/2016] [Indexed: 11/19/2022]
Abstract
During DNA replication, proliferating cell nuclear antigen (PCNA) adopts a ring-shaped structure to promote processive DNA synthesis, acting as a sliding clamp for polymerases. Known posttranslational modifications function at the outer surface of the PCNA ring to favor DNA damage bypass. Here, we demonstrate that acetylation of lysine residues at the inner surface of PCNA is induced by DNA lesions. We show that cohesin acetyltransferase Eco1 targets lysine 20 at the sliding surface of the PCNA ring in vitro and in vivo in response to DNA damage. Mimicking constitutive acetylation stimulates homologous recombination and robustly suppresses the DNA damage sensitivity of mutations in damage tolerance pathways. In comparison to the unmodified trimer, structural differences are observed at the interface between protomers in the crystal structure of the PCNA-K20ac ring. Thus, acetylation regulates PCNA sliding on DNA in the presence of DNA damage, favoring homologous recombination linked to sister-chromatid cohesion.
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Affiliation(s)
- Pierre Billon
- St-Patrick Research Group in Basic Oncology, Laval University Cancer Research Center, Centre de Recherche du CHU de Québec-Axe Oncologie, Quebec City, QC G1R 3S3, Canada
| | - Jian Li
- Department of Biological Sciences and Molecular and Cellular Biology Graduate Program, Ohio University, Athens, OH 45701, USA
| | - Jean-Philippe Lambert
- The Lunenfeld-Tanenbaum Research Institute at Mount Sinai Hospital, Toronto, ON M5G 1X5, Canada
| | - Yizhang Chen
- Department of Biological Sciences and Molecular and Cellular Biology Graduate Program, Ohio University, Athens, OH 45701, USA
| | - Véronique Tremblay
- Ottawa Institute of Systems Biology, Department of Biochemistry, Microbiology, and Immunology, University of Ottawa, 451 Smyth Road, Ottawa, ON K1H 8M5, Canada
| | - Joseph S Brunzelle
- Department of Molecular Pharmacology and Biological Chemistry, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Anne-Claude Gingras
- The Lunenfeld-Tanenbaum Research Institute at Mount Sinai Hospital, Toronto, ON M5G 1X5, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Alain Verreault
- Institute for Research in Immunology and Cancer and Département de Pathologie et Biologie Cellulaire, Université de Montréal, Montreal, QC H3C 3J7, Canada
| | - Tomohiko Sugiyama
- Department of Biological Sciences and Molecular and Cellular Biology Graduate Program, Ohio University, Athens, OH 45701, USA
| | - Jean-Francois Couture
- Ottawa Institute of Systems Biology, Department of Biochemistry, Microbiology, and Immunology, University of Ottawa, 451 Smyth Road, Ottawa, ON K1H 8M5, Canada
| | - Jacques Côté
- St-Patrick Research Group in Basic Oncology, Laval University Cancer Research Center, Centre de Recherche du CHU de Québec-Axe Oncologie, Quebec City, QC G1R 3S3, Canada.
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37
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Johnson C, Gali VK, Takahashi TS, Kubota T. PCNA Retention on DNA into G2/M Phase Causes Genome Instability in Cells Lacking Elg1. Cell Rep 2016; 16:684-95. [PMID: 27373149 PMCID: PMC4956615 DOI: 10.1016/j.celrep.2016.06.030] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Revised: 04/28/2016] [Accepted: 06/03/2016] [Indexed: 12/05/2022] Open
Abstract
Loss of the genome maintenance factor Elg1 causes serious genome instability that leads to cancer, but the underlying mechanism is unknown. Elg1 forms the major subunit of a replication factor C-like complex, Elg1-RLC, which unloads the ring-shaped polymerase clamp PCNA from DNA during replication. Here, we show that prolonged retention of PCNA on DNA into G2/M phase is the major cause of genome instability in elg1Δ yeast. Overexpression-induced accumulation of PCNA on DNA causes genome instability. Conversely, disassembly-prone PCNA mutants that relieve PCNA accumulation rescue the genome instability of elg1Δ cells. Covalent modifications to the retained PCNA make only a minor contribution to elg1Δ genome instability. By engineering cell-cycle-regulated ELG1 alleles, we show that abnormal accumulation of PCNA on DNA during S phase causes moderate genome instability and its retention through G2/M phase exacerbates genome instability. Our results reveal that PCNA unloading by Elg1-RLC is critical for genome maintenance.
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Affiliation(s)
- Catherine Johnson
- Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, Scotland, UK
| | - Vamsi K Gali
- Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, Scotland, UK
| | - Tatsuro S Takahashi
- Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan
| | - Takashi Kubota
- Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, Scotland, UK.
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38
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Abstract
A range of enzymes in DNA replication and repair bind to DNA-clamps: torus-shaped proteins that encircle double-stranded DNA and act as mobile tethers. Clamps from viruses (such as gp45 from the T4 bacteriophage) and eukaryotes (PCNAs) are homotrimers, each protomer containing two repeats of the DNA-clamp motif, while bacterial clamps (pol III β) are homodimers, each protomer containing three DNA-clamp motifs. Clamps need to be flexible enough to allow opening and loading onto primed DNA by clamp loader complexes. Equilibrium and steered molecular dynamics simulations have been used to study DNA-clamp conformation in open and closed forms. The E. coli and PCNA clamps appear to prefer closed, planar conformations. Remarkably, gp45 appears to prefer an open right-handed spiral conformation in solution, in agreement with previously reported biophysical data. The structural preferences of DNA clamps in solution have implications for understanding the duty cycle of clamp-loaders.
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39
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Abstract
Proliferating cell nuclear antigen (PCNA) plays critical roles in many aspects of DNA replication and replication-associated processes, including translesion synthesis, error-free damage bypass, break-induced replication, mismatch repair, and chromatin assembly. Since its discovery, our view of PCNA has evolved from a replication accessory factor to the hub protein in a large protein-protein interaction network that organizes and orchestrates many of the key events at the replication fork. We begin this review article with an overview of the structure and function of PCNA. We discuss the ways its many interacting partners bind and how these interactions are regulated by posttranslational modifications such as ubiquitylation and sumoylation. We then explore the many roles of PCNA in normal DNA replication and in replication-coupled DNA damage tolerance and repair processes. We conclude by considering how PCNA can interact physically with so many binding partners to carry out its numerous roles. We propose that there is a large, dynamic network of linked PCNA molecules at and around the replication fork. This network would serve to increase the local concentration of all the proteins necessary for DNA replication and replication-associated processes and to regulate their various activities.
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40
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Rohleder F, Huang J, Xue Y, Kuper J, Round A, Seidman M, Wang W, Kisker C. FANCM interacts with PCNA to promote replication traverse of DNA interstrand crosslinks. Nucleic Acids Res 2016; 44:3219-32. [PMID: 26825464 PMCID: PMC4838364 DOI: 10.1093/nar/gkw037] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Accepted: 01/12/2016] [Indexed: 12/27/2022] Open
Abstract
FANCM is a highly conserved DNA remodeling enzyme that promotes the activation of the Fanconi anemia DNA repair pathway and facilitates replication traverse of DNA interstrand crosslinks. However, how FANCM interacts with the replication machinery to promote traverse remains unclear. Here, we show that FANCM and its archaeal homolog Hef from Thermoplasma acidophilum interact with proliferating cell nuclear antigen (PCNA), an essential co-factor for DNA polymerases in both replication and repair. The interaction is mediated through a conserved PIP-box; and in human FANCM, it is strongly stimulated by replication stress. A FANCM variant carrying a mutation in the PIP-box is defective in promoting replication traverse of interstrand crosslinks and is also inefficient in promoting FANCD2 monoubiquitination, a key step of the Fanconi anemia pathway. Our data reveal a conserved interaction mode between FANCM and PCNA during replication stress, and suggest that this interaction is essential for FANCM to aid replication machines to traverse DNA interstrand crosslinks prior to post-replication repair.
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Affiliation(s)
- Florian Rohleder
- Rudolf Virchow Center for Experimental Biomedicine, Institute for Structural Biology, University of Würzburg, D-97080 Würzburg, Germany
| | - Jing Huang
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institute of Health, Baltimore, Maryland, MD 21224, USA
| | - Yutong Xue
- Laboratory of Genetics, National Institute on Aging, National Institute of Health, Baltimore, Maryland, MD 21224, USA
| | - Jochen Kuper
- Rudolf Virchow Center for Experimental Biomedicine, Institute for Structural Biology, University of Würzburg, D-97080 Würzburg, Germany
| | - Adam Round
- European Molecular Biology Laboratory, Grenoble Outstation, 71 Avenue des Martyrs, 38042 Grenoble, France Unit for Virus Host-Cell Interactions, Univ. Grenoble Alpes-EMBL-CNRS, 71 Avenue des Martyrs, 38042 Grenoble, France Faculty of Natural sciences, Keele University, Staffordshire ST5 5BG, UK
| | - Michael Seidman
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institute of Health, Baltimore, Maryland, MD 21224, USA
| | - Weidong Wang
- Laboratory of Genetics, National Institute on Aging, National Institute of Health, Baltimore, Maryland, MD 21224, USA
| | - Caroline Kisker
- Rudolf Virchow Center for Experimental Biomedicine, Institute for Structural Biology, University of Würzburg, D-97080 Würzburg, Germany
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41
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Duffy CM, Hilbert BJ, Kelch BA. A Disease-Causing Variant in PCNA Disrupts a Promiscuous Protein Binding Site. J Mol Biol 2015; 428:1023-1040. [PMID: 26688547 DOI: 10.1016/j.jmb.2015.11.029] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Revised: 11/10/2015] [Accepted: 11/21/2015] [Indexed: 11/27/2022]
Abstract
The eukaryotic DNA polymerase sliding clamp, proliferating cell nuclear antigen or PCNA, is a ring-shaped protein complex that surrounds DNA to act as a sliding platform for increasing processivity of cellular replicases and for coordinating various cellular pathways with DNA replication. A single point mutation, Ser228Ile, in the human PCNA gene was recently identified to cause a disease whose symptoms resemble those of DNA damage and repair disorders. The mutation lies near the binding site for most PCNA-interacting proteins. However, the structural consequences of the S228I mutation are unknown. Here, we describe the structure of the disease-causing variant, which reveals a large conformational change that dramatically transforms the binding pocket for PCNA client proteins. We show that the mutation markedly alters the binding energetics for some client proteins, while another, p21(CIP1), is only mildly affected. Structures of the disease variant bound to peptides derived from two PCNA partner proteins reveal that the binding pocket can adjust conformation to accommodate some ligands, indicating that the binding site is dynamic and pliable. Our work has implications for the plasticity of the binding site in PCNA and reveals how a disease mutation selectively alters interactions to a promiscuous binding site that is critical for DNA metabolism.
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Affiliation(s)
- Caroline M Duffy
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Brendan J Hilbert
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Brian A Kelch
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605, USA
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42
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Lau WCY, Li Y, Zhang Q, Huen MSY. Molecular architecture of the Ub-PCNA/Pol η complex bound to DNA. Sci Rep 2015; 5:15759. [PMID: 26503230 PMCID: PMC4621508 DOI: 10.1038/srep15759] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Accepted: 09/29/2015] [Indexed: 01/13/2023] Open
Abstract
Translesion synthesis (TLS) is the mechanism by which DNA polymerases replicate through unrepaired DNA lesions. TLS is activated by monoubiquitination of the homotrimeric proliferating cell nuclear antigen (PCNA) at lysine-164, followed by the switch from replicative to specialized polymerases at DNA damage sites. Pol η belongs to the Y-Family of specialized polymerases that can efficiently bypass UV-induced lesions. Like other members of the Y-Family polymerases, its recruitment to the damaged sites is mediated by the interaction with monoubiquitinated PCNA (Ub-PCNA) via its ubiquitin-binding domain and non-canonical PCNA-interacting motif in the C-terminal region. The structural determinants underlying the direct recognition of Ub-PCNA by Pol η, or Y-Family polymerases in general, remain largely unknown. Here we report a structure of the Ub-PCNA/Pol η complex bound to DNA determined by single-particle electron microscopy (EM). The overall obtained structure resembles that of the editing PCNA/PolB complex. Analysis of the map revealed the conformation of ubiquitin that binds the C-terminal domain of Pol η. Our present study suggests that the Ub-PCNA/Pol η interaction requires the formation of a structured binding interface, which is dictated by the inherent flexibility of Ub-PCNA.
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Affiliation(s)
- Wilson C Y Lau
- School of Biomedical Sciences, The University of Hong Kong, Hong Kong, China.,State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong, China
| | - Yinyin Li
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Qinfen Zhang
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Michael S Y Huen
- School of Biomedical Sciences, The University of Hong Kong, Hong Kong, China.,State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong, China
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43
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Pi F, Vieweger M, Zhao Z, Wang S, Guo P. Discovery of a new method for potent drug development using power function of stoichiometry of homomeric biocomplexes or biological nanomotors. Expert Opin Drug Deliv 2015; 13:23-36. [PMID: 26307193 DOI: 10.1517/17425247.2015.1082544] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
INTRODUCTION Multidrug resistance and the appearance of incurable diseases inspire the quest for potent therapeutics. AREAS COVERED We review a new methodology in designing potent drugs by targeting multi-subunit homomeric biological motors, machines or complexes with Z > 1 and K = 1, where Z is the stoichiometry of the target, and K is the number of drugged subunits required to block the function of the complex. The condition is similar to a series electrical circuit of Christmas decorations: failure of one light bulb causes the entire lighting system to lose power. In most multi-subunit, homomeric biological systems, a sequential coordination or cooperative action mechanism is utilized, thus K equals 1. Drug inhibition depends on the ratio of drugged to non-drugged complexes. When K = 1, and Z > 1, the inhibition effect follows a power law with respect to Z, leading to enhanced drug potency. The hypothesis that the potency of drug inhibition depends on the stoichiometry of the targeted biological complexes was recently quantified by Yang-Hui's Triangle (or binomial distribution), and proved using a highly sensitive in vitro phi29 viral DNA packaging system. Examples of targeting homomeric bio-complexes with high stoichiometry for potent drug discovery are discussed. EXPERT OPINION Biomotors with multiple subunits are widespread in viruses, bacteria and cells, making this approach generally applicable in the development of inhibition drugs with high efficiency.
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Affiliation(s)
- Fengmei Pi
- a 1 University of Kentucky, Nanobiotechnology Center , Lexington, KY 40536, USA.,b 2 University of Kentucky, Markey Cancer Center , Lexington, KY 40536, USA.,c 3 University of Kentucky, Department of Pharmaceutical Sciences , 789 S. Limestone Street, Room # 576, Lexington, KY 40536, USA +1 859 218 0128 ; +1 859 257 1307 ;
| | - Mario Vieweger
- a 1 University of Kentucky, Nanobiotechnology Center , Lexington, KY 40536, USA.,b 2 University of Kentucky, Markey Cancer Center , Lexington, KY 40536, USA.,c 3 University of Kentucky, Department of Pharmaceutical Sciences , 789 S. Limestone Street, Room # 576, Lexington, KY 40536, USA +1 859 218 0128 ; +1 859 257 1307 ;
| | - Zhengyi Zhao
- a 1 University of Kentucky, Nanobiotechnology Center , Lexington, KY 40536, USA.,b 2 University of Kentucky, Markey Cancer Center , Lexington, KY 40536, USA.,c 3 University of Kentucky, Department of Pharmaceutical Sciences , 789 S. Limestone Street, Room # 576, Lexington, KY 40536, USA +1 859 218 0128 ; +1 859 257 1307 ;
| | - Shaoying Wang
- a 1 University of Kentucky, Nanobiotechnology Center , Lexington, KY 40536, USA.,b 2 University of Kentucky, Markey Cancer Center , Lexington, KY 40536, USA.,c 3 University of Kentucky, Department of Pharmaceutical Sciences , 789 S. Limestone Street, Room # 576, Lexington, KY 40536, USA +1 859 218 0128 ; +1 859 257 1307 ;
| | - Peixuan Guo
- a 1 University of Kentucky, Nanobiotechnology Center , Lexington, KY 40536, USA.,b 2 University of Kentucky, Markey Cancer Center , Lexington, KY 40536, USA.,c 3 University of Kentucky, Department of Pharmaceutical Sciences , 789 S. Limestone Street, Room # 576, Lexington, KY 40536, USA +1 859 218 0128 ; +1 859 257 1307 ;
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44
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45
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Salama SA, Arab HH, Omar HA, Maghrabi IA, Snapka RM. Nicotine mediates hypochlorous acid-induced nuclear protein damage in mammalian cells. Inflammation 2015; 37:785-92. [PMID: 24357417 DOI: 10.1007/s10753-013-9797-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Activated neutrophils secrete hypochlorous acid (HOCl) into the extracellular space of inflamed tissues. Because of short diffusion distance in biological fluids, HOCl-damaging effect is restricted to the extracellular compartment. The current study aimed at investigating the ability of nicotine, a component of tobacco and electronic cigarettes, to mediate HOCl-induced intracellular damage. We report, for the first time, that HOCl reacts with nicotine to produce nicotine chloramine (Nic-Cl). Nic-Cl caused dose-dependent damage to proliferating cell nuclear antigen (PCNA), a nuclear protein, in cultured mammalian lung and kidney cells. Vitamin C, vitamin E analogue (Trolox), glutathione, and N-acetyl-L-cysteine inhibited the Nic-Cl-induced PCNA damage, implicating oxidation in PCNA damage. These findings point out the ability of nicotine to mediate HOCl-induced intracellular damage and suggest antioxidants as protective measures. The results also raise the possibility that Nic-Cl can be created in the inflamed tissues of tobacco and electronic cigarette smokers and may contribute to smoking-related diseases.
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Affiliation(s)
- Samir A Salama
- Division of Biochemistry and GTMR Unit, College of Clinical Pharmacy, Taif University, Al-Haweiah, Taif, 21974, Kingdom of Saudi Arabia,
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46
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Hwang BJ, Jin J, Gunther R, Madabushi A, Shi G, Wilson GM, Lu AL. Association of the Rad9-Rad1-Hus1 checkpoint clamp with MYH DNA glycosylase and DNA. DNA Repair (Amst) 2015; 31:80-90. [PMID: 26021743 DOI: 10.1016/j.dnarep.2015.05.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Revised: 05/04/2015] [Accepted: 05/08/2015] [Indexed: 12/18/2022]
Abstract
Cell cycle checkpoints provide surveillance mechanisms to activate the DNA damage response, thus preserving genomic integrity. The heterotrimeric Rad9-Rad1-Hus1 (9-1-1) clamp is a DNA damage response sensor and can be loaded onto DNA. 9-1-1 is involved in base excision repair (BER) by interacting with nearly every enzyme in BER. Here, we show that individual 9-1-1 components play distinct roles in BER directed by MYH DNA glycosylase. Analyses of Hus1 deletion mutants revealed that the interdomain connecting loop (residues 134-155) is a key determinant of MYH binding. Both the N-(residues 1-146) and C-terminal (residues 147-280) halves of Hus1, which share structural similarity, can interact with and stimulate MYH. The Hus1(K136A) mutant retains physical interaction with MYH but cannot stimulate MYH glycosylase activity. The N-terminal domain, but not the C-terminal half of Hus1 can also bind DNA with moderate affinity. Intact Rad9 expressed in bacteria binds to and stimulates MYH weakly. However, Rad9(1-266) (C-terminal truncated Rad9) can stimulate MYH activity and bind DNA with high affinity, close to that displayed by heterotrimeric 9(1-266)-1-1 complexes. Conversely, Rad1 has minimal roles in stimulating MYH activity or binding to DNA. Finally, we show that preferential recruitment of 9(1-266)-1-1 to 5'-recessed DNA substrates is an intrinsic property of this complex and is dependent on complex formation. Together, our findings provide a mechanistic rationale for unique contributions by individual 9-1-1 subunits to MYH-directed BER based on subunit asymmetry in protein-protein interactions and DNA binding events.
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Affiliation(s)
- Bor-Jang Hwang
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD 21201, United States
| | - Jin Jin
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD 21201, United States
| | - Randall Gunther
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD 21201, United States
| | - Amrita Madabushi
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD 21201, United States; Department of Natural and Physical Sciences, Life Sciences Institute; Baltimore City Community College, Baltimore, MD 21201, United States
| | - Guoli Shi
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD 21201, United States; University of Maryland School of Nursing, Baltimore, MD 21201, United States
| | - Gerald M Wilson
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD 21201, United States; Greenebaum Cancer Center, University of Maryland School of Medicine, Baltimore, MD 21201, United States
| | - A-Lien Lu
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD 21201, United States; Greenebaum Cancer Center, University of Maryland School of Medicine, Baltimore, MD 21201, United States.
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47
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Lim PX, Patel DR, Poisson KE, Basuita M, Tsai C, Lyndaker AM, Hwang BJ, Lu AL, Weiss RS. Genome Protection by the 9-1-1 Complex Subunit HUS1 Requires Clamp Formation, DNA Contacts, and ATR Signaling-independent Effector Functions. J Biol Chem 2015; 290:14826-40. [PMID: 25911100 DOI: 10.1074/jbc.m114.630640] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2014] [Indexed: 01/30/2023] Open
Abstract
The RAD9A-HUS1-RAD1 (9-1-1) complex is a heterotrimeric clamp that promotes checkpoint signaling and repair at DNA damage sites. In this study, we elucidated HUS1 functional residues that drive clamp assembly, DNA interactions, and downstream effector functions. First, we mapped a HUS1-RAD9A interface residue that was critical for 9-1-1 assembly and DNA loading. Next, we identified multiple positively charged residues in the inner ring of HUS1 that were crucial for genotoxin-induced 9-1-1 chromatin localization and ATR signaling. Finally, we found two hydrophobic pockets on the HUS1 outer surface that were important for cell survival after DNA damage. Interestingly, these pockets were not required for 9-1-1 chromatin localization or ATR-mediated CHK1 activation but were necessary for interactions between HUS1 and its binding partner MYH, suggesting that they serve as interaction domains for the recruitment and coordination of downstream effectors at damage sites. Together, these results indicate that, once properly loaded onto damaged DNA, the 9-1-1 complex executes multiple, separable functions that promote genome maintenance.
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Affiliation(s)
- Pei Xin Lim
- From the Department of Biomedical Sciences, Cornell University, Ithaca, New York 14853 and
| | - Darshil R Patel
- From the Department of Biomedical Sciences, Cornell University, Ithaca, New York 14853 and
| | - Kelsey E Poisson
- From the Department of Biomedical Sciences, Cornell University, Ithaca, New York 14853 and
| | - Manpreet Basuita
- From the Department of Biomedical Sciences, Cornell University, Ithaca, New York 14853 and
| | - Charlton Tsai
- From the Department of Biomedical Sciences, Cornell University, Ithaca, New York 14853 and
| | - Amy M Lyndaker
- From the Department of Biomedical Sciences, Cornell University, Ithaca, New York 14853 and
| | - Bor-Jang Hwang
- the Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, Maryland 21201
| | - A-Lien Lu
- the Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, Maryland 21201
| | - Robert S Weiss
- From the Department of Biomedical Sciences, Cornell University, Ithaca, New York 14853 and
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48
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Structure of p15PAF–PCNA complex and implications for clamp sliding during DNA replication and repair. Nat Commun 2015; 6:6439. [DOI: 10.1038/ncomms7439] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Accepted: 01/29/2015] [Indexed: 01/27/2023] Open
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49
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Niiranen L, Lian K, Johnson KA, Moe E. Crystal structure of the DNA polymerase III β subunit (β-clamp) from the extremophile Deinococcus radiodurans. BMC STRUCTURAL BIOLOGY 2015; 15:5. [PMID: 25886944 PMCID: PMC4350885 DOI: 10.1186/s12900-015-0032-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Accepted: 02/13/2015] [Indexed: 02/08/2023]
Abstract
BACKGROUND Deinococcus radiodurans is an extremely radiation and desiccation resistant bacterium which can tolerate radiation doses up to 5,000 Grays without losing viability. We are studying the role of DNA repair and replication proteins for this unusual phenotype by a structural biology approach. The DNA polymerase III β subunit (β-clamp) acts as a sliding clamp on DNA, promoting the binding and processivity of many DNA-acting proteins, and here we report the crystal structure of D. radiodurans β-clamp (Drβ-clamp) at 2.0 Å resolution. RESULTS The sequence verification process revealed that at the time of the study the gene encoding Drβ-clamp was wrongly annotated in the genome database, encoding a protein of 393 instead of 362 amino acids. The short protein was successfully expressed, purified and used for crystallisation purposes in complex with Cy5-labeled DNA. The structure, which was obtained from blue crystals, shows a typical ring-shaped bacterial β-clamp formed of two monomers, each with three domains of identical topology, but with no visible DNA in electron density. A visualisation of the electrostatic surface potential reveals a highly negatively charged outer surface while the inner surface and the dimer forming interface have a more even charge distribution. CONCLUSIONS The structure of Drβ-clamp was determined to 2.0 Å resolution and shows an evenly distributed electrostatic surface charge on the DNA interacting side. We hypothesise that this charge distribution may facilitate efficient movement on encircled DNA and help ensure efficient DNA metabolism in D. radiodurans upon exposure to high doses of ionizing irradiation or desiccation.
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Affiliation(s)
- Laila Niiranen
- The Norwegian Structural Biology Center (NorStruct), Department of Chemistry, UIT - the Arctic University of Norway, N-9037, Tromsø, Norway.
| | - Kjersti Lian
- The Norwegian Structural Biology Center (NorStruct), Department of Chemistry, UIT - the Arctic University of Norway, N-9037, Tromsø, Norway.
| | - Kenneth A Johnson
- The Norwegian Structural Biology Center (NorStruct), Department of Chemistry, UIT - the Arctic University of Norway, N-9037, Tromsø, Norway.
| | - Elin Moe
- The Norwegian Structural Biology Center (NorStruct), Department of Chemistry, UIT - the Arctic University of Norway, N-9037, Tromsø, Norway. .,The Macromolecular Crystallography Unit, Instituto de Tecnologia Química e Biológica (ITQB), Universidade Nova de Lisboa, Oeiras, 2780-157, Portugal.
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Common mechanisms of DNA translocation motors in bacteria and viruses using one-way revolution mechanism without rotation. Biotechnol Adv 2015; 32:853-72. [PMID: 24913057 DOI: 10.1016/j.biotechadv.2014.01.006] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2013] [Revised: 01/24/2014] [Accepted: 01/25/2014] [Indexed: 12/15/2022]
Abstract
Biomotors were once described into two categories: linear motor and rotation motor. Recently, a third type of biomotor with revolution mechanism without rotation has been discovered. By analogy, rotation resembles the Earth rotating on its axis in a complete cycle every 24h, while revolution resembles the Earth revolving around the Sun one circle per 365 days (see animations http://nanobio.uky.edu/movie.html). The action of revolution that enables a motor free of coiling and torque has solved many puzzles and debates that have occurred throughout the history of viral DNA packaging motor studies. It also settles the discrepancies concerning the structure, stoichiometry, and functioning of DNA translocation motors. This review uses bacteriophages Phi29, HK97, SPP1, P22, T4, and T7 as well as bacterial DNA translocase FtsK and SpoIIIE or the large eukaryotic dsDNA viruses such as mimivirus and vaccinia virus as examples to elucidate the puzzles. These motors use ATPase, some of which have been confirmed to be a hexamer, to revolve around the dsDNA sequentially. ATP binding induces conformational change and possibly an entropy alteration in ATPase to a high affinity toward dsDNA; but ATP hydrolysis triggers another entropic and conformational change in ATPase to a low affinity for DNA, by which dsDNA is pushed toward an adjacent ATPase subunit. The rotation and revolution mechanisms can be distinguished by the size of channel: the channels of rotation motors are equal to or smaller than 2 nm, that is the size of dsDNA, whereas channels of revolution motors are larger than 3 nm. Rotation motors use parallel threads to operate with a right-handed channel, while revolution motors use a left-handed channel to drive the right-handed DNA in an anti-chiral arrangement. Coordination of several vector factors in the same direction makes viral DNA-packaging motors unusually powerful and effective. Revolution mechanism that avoids DNA coiling in translocating the lengthy genomic dsDNA helix could be advantageous for cell replication such as bacterial binary fission and cell mitosis without the need for topoisomerase or helicase to consume additional energy.
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