1
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Jiang YK, Medley EA, Brown GW. Two independent DNA repair pathways cause mutagenesis in template switching deficient Saccharomyces cerevisiae. Genetics 2023; 225:iyad153. [PMID: 37594077 DOI: 10.1093/genetics/iyad153] [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: 06/27/2023] [Accepted: 08/08/2023] [Indexed: 08/19/2023] Open
Abstract
Upon DNA replication stress, cells utilize the postreplication repair pathway to repair single-stranded DNA and maintain genome integrity. Postreplication repair is divided into 2 branches: error-prone translesion synthesis, signaled by proliferating cell nuclear antigen (PCNA) monoubiquitination, and error-free template switching, signaled by PCNA polyubiquitination. In Saccharomyces cerevisiae, Rad5 is involved in both branches of repair during DNA replication stress. When the PCNA polyubiquitination function of Rad5 s disrupted, Rad5 recruits translesion synthesis polymerases to stalled replication forks, resulting in mutagenic repair. Details of how mutagenic repair is carried out, as well as the relationship between Rad5-mediated mutagenic repair and the canonical PCNA-mediated mutagenic repair, remain to be understood. We find that Rad5-mediated mutagenic repair requires the translesion synthesis polymerase ζ but does not require other yeast translesion polymerase activities. Furthermore, we show that Rad5-mediated mutagenic repair is independent of PCNA binding by Rev1 and so is separable from canonical mutagenic repair. In the absence of error-free template switching, both modes of mutagenic repair contribute additively to replication stress response in a replication timing-independent manner. Cellular contexts where error-free template switching is compromised are not simply laboratory phenomena, as we find that a natural variant in RAD5 is defective in PCNA polyubiquitination and therefore defective in error-free repair, resulting in Rad5- and PCNA-mediated mutagenic repair. Our results highlight the importance of Rad5 in regulating spontaneous mutagenesis and genetic diversity in S. cerevisiae through different modes of postreplication repair.
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Affiliation(s)
- Yangyang Kate Jiang
- Department of Biochemistry, University of Toronto, 1 King's College Circle, Toronto, ON M5S 1A8, Canada
- Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON M5S 3E1, Canada
| | - Eleanor A Medley
- Department of Biochemistry, University of Toronto, 1 King's College Circle, Toronto, ON M5S 1A8, Canada
- Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON M5S 3E1, Canada
| | - Grant W Brown
- Department of Biochemistry, University of Toronto, 1 King's College Circle, Toronto, ON M5S 1A8, Canada
- Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON M5S 3E1, Canada
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2
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Muellner J, Schmidt KH. Helicase activities of Rad5 and Rrm3 genetically interact in the prevention of recombinogenic DNA lesions in Saccharomyces cerevisiae. DNA Repair (Amst) 2023; 126:103488. [PMID: 37054652 PMCID: PMC10399609 DOI: 10.1016/j.dnarep.2023.103488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 03/09/2023] [Accepted: 03/28/2023] [Indexed: 03/31/2023]
Abstract
The genome must be monitored to ensure its duplication is completed accurately to prevent genome instability. In Saccharomyces cerevisiae, the 5' to 3' DNA helicase Rrm3, a member of the conserved PIF1 family, facilitates replication fork progression through an unknown mechanism. Disruption of Rrm3 helicase activity leads to increased replication fork pausing throughout the yeast genome. Here, we show that Rrm3 contributes to replication stress tolerance in the absence of the fork reversal activity of Rad5, defined by its HIRAN domain and DNA helicase activity, but not in the absence of Rad5's ubiquitin ligase activity. The Rrm3 and Rad5 helicase activities also interact in the prevention of recombinogenic DNA lesions, and DNA lesions that accumulate in their absence need to be salvaged by a Rad59-dependent recombination pathway. Disruption of the structure-specific endonuclease Mus81 leads to accumulation of recombinogenic DNA lesions and chromosomal rearrangements in the absence of Rrm3, but not Rad5. Thus, at least two mechanisms exist to overcome fork stalling at replication barriers, defined by Rad5-mediated fork reversal and Mus81-mediated cleavage, and contribute to the maintenance of chromosome stability in the absence of Rrm3.
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Affiliation(s)
- Julius Muellner
- Department of Molecular Biosciences, University of South Florida, Tampa, FL 33620, United States; Graduate program in Cell and Molecular Biology, University of South Florida, Tampa, FL 33620, United States
| | - Kristina H Schmidt
- Department of Molecular Biosciences, University of South Florida, Tampa, FL 33620, United States; Graduate program in Cell and Molecular Biology, University of South Florida, Tampa, FL 33620, United States; Cancer Biology and Evolution Program, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL 33612, United States.
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3
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Krawczyk M, Halas A, Sledziewska-Gojska E. A novel role for Mms2 in the control of spontaneous mutagenesis and Pol3 abundance. DNA Repair (Amst) 2023; 125:103484. [PMID: 36934633 DOI: 10.1016/j.dnarep.2023.103484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 02/27/2023] [Accepted: 03/09/2023] [Indexed: 03/14/2023]
Abstract
Mms2 is a ubiquitin E2-variant protein with a very well-documented function in the tolerance pathway that protects both human and yeast cells from the lethal and mutagenic effects of DNA damage. Interestingly, a high expression level of human MMS2 is associated with poor survival prognosis in different cancer diseases. Here we have analyzed the physiological effects of Mms2 overproduction in yeast cells. We show that an increased level of this protein causes a spontaneous mutator effect independent of Ubc13, a cognate partner of Mms2 in the PCNA-polyubiquitinating complex responsible for the template switch. Instead, this new promutagenic role of Mms2 requires Ubc4 (E2) and two ubiquitin ligases of HECT and RING families, Rsp5 and Not4, respectively. We have established that the promutagenic activity of Mms2 is dependent on the activities of error-prone DNA polymerase ζ and Rev1. Additionally, it requires the ubiquitination of K164 in PCNA which facilitates recruitment of these translesion polymerases to the replication complex. Importantly, we have established also that the cellular abundance of Mms2 influences the cellular level of Pol3, the catalytic subunit of replicative DNA polymerase δ. Lack of Mms2 increases the Pol3 abundance, whereas in response to Mms2 overproduction the Pol3 level decreases. We hypothesize that increased levels of spontaneous mutagenesis may result from the Mms2-induced reduction in Pol3 accumulation leading to increased participation of error-prone polymerase ζ in the replication complex.
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Affiliation(s)
- Michal Krawczyk
- Laboratory of Mutagenesis and DNA Damage Tolerance, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106 Warsaw, Poland
| | - Agnieszka Halas
- Laboratory of Mutagenesis and DNA Damage Tolerance, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106 Warsaw, Poland
| | - Ewa Sledziewska-Gojska
- Laboratory of Mutagenesis and DNA Damage Tolerance, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106 Warsaw, Poland.
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4
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González-Garrido C, Prado F. Parental histone distribution and location of the replication obstacle at nascent strands control homologous recombination. Cell Rep 2023; 42:112174. [PMID: 36862554 DOI: 10.1016/j.celrep.2023.112174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 12/09/2022] [Accepted: 02/10/2023] [Indexed: 03/03/2023] Open
Abstract
The advance and stability of replication forks rely on a tight co-regulation of DNA synthesis and nucleosome assembly. We show that mutants affected in parental histone recycling are impaired in the recombinational repair of the single-stranded DNA gaps generated in response to DNA adducts that hamper replication, which are then filled in by translesion synthesis. These recombination defects are in part due to an excess of parental nucleosomes at the invaded strand that destabilizes the sister chromatid junction formed after strand invasion through a Srs2-dependent mechanism. In addition, we show that a dCas9∗/R-loop is more recombinogenic when the dCas9∗/DNA-RNA hybrid interferes with the lagging than with the leading strand, and this recombination is particularly sensitive to problems in the deposition of parental histones at the strand that contains the hindrance. Therefore, parental histone distribution and location of the replication obstacle at the lagging or leading strand regulate homologous recombination.
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Affiliation(s)
- Cristina González-Garrido
- Centro Andaluz de Biología Molecular y Medicina Regenerativa-CABIMER, Consejo Superior de Investigaciones Científicas, Universidad de Sevilla, Universidad Pablo de Olavide, Seville, Spain
| | - Félix Prado
- Centro Andaluz de Biología Molecular y Medicina Regenerativa-CABIMER, Consejo Superior de Investigaciones Científicas, Universidad de Sevilla, Universidad Pablo de Olavide, Seville, Spain.
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5
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Masłowska KH, Pagès V. Rad5 participates in lesion bypass through its Rev1-binding and ubiquitin ligase domains, but not through its helicase function. Front Mol Biosci 2022; 9:1062027. [DOI: 10.3389/fmolb.2022.1062027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Accepted: 11/21/2022] [Indexed: 12/04/2022] Open
Abstract
DNA Damage Tolerance (DDT) functions to bypass replication-blocking lesions and is divided into two distinct pathways: error-prone Translesion Synthesis (TLS) and error-free Damage Avoidance (DA). Rad5 is a multifunctional protein that is involved in these DDT processes. Saccharomyces cerevisiae Rad5 contains three well defined domains: a RING domain that promotes PCNA polyubiquitination, a ssDNA-dependent ATPase/helicase domain, and a Rev1-binding domain. Both the RING domain and the ATPase/helicase domain are conserved in human Rad5 ortholog HLTF. In this study we used domain-specific mutants to address the contribution of each of the Rad5 domains to the lesion tolerance. We demonstrate that the two critical functions of Rad5 during DNA damage tolerance are the activation of template switching through polyubiquitination of PCNA and the recruitment of TLS polymerases, and that loss of one of those functions can be compensated by increased usage of the other. We also show that, unlike previously suggested, the helicase activity does not play any role in lesion tolerance.
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6
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Mechanistic insights into the multiple activities of the Rad5 family of enzymes. J Mol Biol 2022; 434:167581. [DOI: 10.1016/j.jmb.2022.167581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2022] [Revised: 04/01/2022] [Accepted: 04/02/2022] [Indexed: 11/18/2022]
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7
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Wegmann S, Meister C, Renz C, Yakoub G, Wollscheid HP, Takahashi DT, Mikicic I, Beli P, Ulrich HD. Linkage reprogramming by tailor-made E3s reveals polyubiquitin chain requirements in DNA-damage bypass. Mol Cell 2022; 82:1589-1602.e5. [PMID: 35263628 PMCID: PMC9098123 DOI: 10.1016/j.molcel.2022.02.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 01/05/2022] [Accepted: 02/08/2022] [Indexed: 12/22/2022]
Abstract
A polyubiquitin chain can adopt a variety of shapes, depending on how the ubiquitin monomers are joined. However, the relevance of linkage for the signaling functions of polyubiquitin chains is often poorly understood because of our inability to control or manipulate this parameter in vivo. Here, we present a strategy for reprogramming polyubiquitin chain linkage by means of tailor-made, linkage- and substrate-selective ubiquitin ligases. Using the polyubiquitylation of the budding yeast replication factor PCNA in response to DNA damage as a model case, we show that altering the features of a polyubiquitin chain in vivo can change the fate of the modified substrate. We also provide evidence for redundancy between distinct but structurally similar linkages, and we demonstrate by proof-of-principle experiments that the method can be generalized to targets beyond PCNA. Our study illustrates a promising approach toward the in vivo analysis of polyubiquitin signaling.
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Affiliation(s)
- Sabrina Wegmann
- Institute of Molecular Biology gGmbH (IMB), Ackermannweg 4, 55128 Mainz, Germany
| | - Cindy Meister
- Institute of Molecular Biology gGmbH (IMB), Ackermannweg 4, 55128 Mainz, Germany
| | - Christian Renz
- Institute of Molecular Biology gGmbH (IMB), Ackermannweg 4, 55128 Mainz, Germany
| | - George Yakoub
- Institute of Molecular Biology gGmbH (IMB), Ackermannweg 4, 55128 Mainz, Germany
| | | | - Diane T Takahashi
- Université de Strasbourg, UMR7242 Biotechnologie et Signalisation Cellulaire, Ecole Supérieure de Biotechnologie de Strasbourg, 10413 Illkirch, Strasbourg, France
| | - Ivan Mikicic
- Institute of Molecular Biology gGmbH (IMB), Ackermannweg 4, 55128 Mainz, Germany
| | - Petra Beli
- Institute of Molecular Biology gGmbH (IMB), Ackermannweg 4, 55128 Mainz, Germany; Institute for Developmental Biology and Neurobiology, Johannes Gutenberg-Universität, 55128 Mainz, Germany
| | - Helle D Ulrich
- Institute of Molecular Biology gGmbH (IMB), Ackermannweg 4, 55128 Mainz, Germany.
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8
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Toth R, Balogh D, Pinter L, Jaksa G, Szeplaki B, Graf A, Gyorfy Z, Enyedi MZ, Kiss E, Haracska L, Unk I. The Rad5 Helicase and RING Domains Contribute to Genome Stability through their Independent Catalytic Activities. J Mol Biol 2022; 434:167437. [PMID: 34990655 DOI: 10.1016/j.jmb.2021.167437] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 12/08/2021] [Accepted: 12/28/2021] [Indexed: 11/27/2022]
Abstract
Genomic stability is compromised by DNA damage that obstructs replication. Rad5 plays a prominent role in DNA damage bypass processes that evolved to ensure the continuation of stalled replication. Like its human orthologs, the HLTF and SHPRH tumor suppressors, yeast Rad5 has a RING domain that supports ubiquitin ligase activity promoting PCNA polyubiquitylation and a helicase domain that in the case of HLTF and Rad5 was shown to exhibit an ATPase-linked replication fork reversal activity. The RING domain is embedded in the helicase domain, confusing their separate investigation and the understanding of the exact role of Rad5 in DNA damage bypass. Particularly, it is still debated whether the helicase domain plays a catalytic or a non-enzymatic role during error-free damage bypass and whether it facilitates a function separately from the RING domain. In this study, through in vivo and in vitro characterization of domain-specific mutants, we delineate the contributions of the two domains to Rad5 function. Yeast genetic experiments and whole-genome sequencing complemented with biochemical assays demonstrate that the ubiquitin ligase and the ATPase-linked activities of Rad5 exhibit independent catalytic activities in facilitating separate pathways during error-free lesion bypass. Our results also provide important insights into the mutagenic role of Rad5 and indicate its tripartite contribution to DNA damage tolerance.
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Affiliation(s)
- Robert Toth
- DNA Repair Research Group, Institute of Genetics, Biological Research Centre, Szeged, Eotvos Loránd Research Network, Szeged H-6726, Hungary; University of Szeged, Doctoral School of Biology, Hungary
| | - David Balogh
- HCEMM-BRC Mutagenesis and Carcinogenesis Research Group, Institute of Genetics, Biological Research Centre, Szeged, Eotvos Loránd Research Network, Szeged H-6726, Hungary
| | | | | | | | - Alexandra Graf
- HCEMM-BRC Mutagenesis and Carcinogenesis Research Group, Institute of Genetics, Biological Research Centre, Szeged, Eotvos Loránd Research Network, Szeged H-6726, Hungary
| | - Zsuzsanna Gyorfy
- DNA Repair Research Group, Institute of Genetics, Biological Research Centre, Szeged, Eotvos Loránd Research Network, Szeged H-6726, Hungary
| | - Marton Zs Enyedi
- HCEMM-BRC Mutagenesis and Carcinogenesis Research Group, Institute of Genetics, Biological Research Centre, Szeged, Eotvos Loránd Research Network, Szeged H-6726, Hungary; Delta Bio 2000 Ltd., Szeged H-6726, Hungary
| | - Erno Kiss
- HCEMM-BRC Mutagenesis and Carcinogenesis Research Group, Institute of Genetics, Biological Research Centre, Szeged, Eotvos Loránd Research Network, Szeged H-6726, Hungary
| | - Lajos Haracska
- HCEMM-BRC Mutagenesis and Carcinogenesis Research Group, Institute of Genetics, Biological Research Centre, Szeged, Eotvos Loránd Research Network, Szeged H-6726, Hungary
| | - Ildiko Unk
- DNA Repair Research Group, Institute of Genetics, Biological Research Centre, Szeged, Eotvos Loránd Research Network, Szeged H-6726, Hungary.
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9
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Elserafy M, El-Shiekh I, Fleifel D, Atteya R, AlOkda A, Abdrabbou MM, Nasr M, El-Khamisy SF. A role for Rad5 in ribonucleoside monophosphate (rNMP) tolerance. Life Sci Alliance 2021; 4:4/10/e202000966. [PMID: 34407997 PMCID: PMC8380674 DOI: 10.26508/lsa.202000966] [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: 11/19/2020] [Revised: 07/24/2021] [Accepted: 07/03/2021] [Indexed: 11/29/2022] Open
Abstract
Ribonucleoside incorporation in genomic DNA poses a significant threat to genomic integrity. Here, we describe how cells tolerate this threat and discuss implications for cancer therapeutics. Ribonucleoside monophosphate (rNMP) incorporation in genomic DNA poses a significant threat to genomic integrity. In addition to repair, DNA damage tolerance mechanisms ensure replication progression upon encountering unrepaired lesions. One player in the tolerance mechanism is Rad5, which is an E3 ubiquitin ligase and helicase. Here, we report a new role for yeast Rad5 in tolerating rNMP incorporation, in the absence of the bona fide ribonucleotide excision repair pathway via RNase H2. This role of Rad5 is further highlighted after replication stress induced by hydroxyurea or by increasing rNMP genomic burden using a mutant DNA polymerase (Pol ε - Pol2-M644G). We further demonstrate the importance of the ATPase and ubiquitin ligase domains of Rad5 in rNMP tolerance. These findings suggest a similar role for the human Rad5 homologues helicase-like transcription factor (HLTF) and SNF2 Histone Linker PHD RING Helicase (SHPRH) in rNMP tolerance, which may impact the response of cancer cells to replication stress-inducing therapeutics.
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Affiliation(s)
- Menattallah Elserafy
- Center for Genomics, Helmy Institute for Medical Sciences, Zewail City of Science and Technology, Giza, Egypt.,University of Science and Technology, Zewail City of Science and Technology, Giza, Egypt
| | - Iman El-Shiekh
- Center for Genomics, Helmy Institute for Medical Sciences, Zewail City of Science and Technology, Giza, Egypt.,University of Science and Technology, Zewail City of Science and Technology, Giza, Egypt
| | - Dalia Fleifel
- Center for Genomics, Helmy Institute for Medical Sciences, Zewail City of Science and Technology, Giza, Egypt
| | - Reham Atteya
- Center for Genomics, Helmy Institute for Medical Sciences, Zewail City of Science and Technology, Giza, Egypt
| | - Abdelrahman AlOkda
- Center for Genomics, Helmy Institute for Medical Sciences, Zewail City of Science and Technology, Giza, Egypt.,University of Science and Technology, Zewail City of Science and Technology, Giza, Egypt
| | - Mohamed M Abdrabbou
- Center for Genomics, Helmy Institute for Medical Sciences, Zewail City of Science and Technology, Giza, Egypt.,University of Science and Technology, Zewail City of Science and Technology, Giza, Egypt
| | - Mostafa Nasr
- Center for Genomics, Helmy Institute for Medical Sciences, Zewail City of Science and Technology, Giza, Egypt.,University of Science and Technology, Zewail City of Science and Technology, Giza, Egypt
| | - Sherif F El-Khamisy
- Center for Genomics, Helmy Institute for Medical Sciences, Zewail City of Science and Technology, Giza, Egypt .,The Healthy Lifespan Institute and Institute of Neuroscience, School of Bioscience, University of Sheffield, South Yorkshire, UK.,The Institute of Cancer Therapeutics, University of Bradford, West Yorkshire, UK.,Center for Genomics, Zewail City of Science and Technology, Giza, Egypt
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10
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Arbel M, Liefshitz B, Kupiec M. DNA damage bypass pathways and their effect on mutagenesis in yeast. FEMS Microbiol Rev 2021; 45:5896953. [PMID: 32840566 DOI: 10.1093/femsre/fuaa038] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 08/23/2020] [Indexed: 12/11/2022] Open
Abstract
What is the origin of mutations? In contrast to the naïve notion that mutations are unfortunate accidents, genetic research in microorganisms has demonstrated that most mutations are created by genetically encoded error-prone repair mechanisms. However, error-free repair pathways also exist, and it is still unclear how cells decide when to use one repair method or the other. Here, we summarize what is known about the DNA damage tolerance mechanisms (also known as post-replication repair) for perhaps the best-studied organism, the yeast Saccharomyces cerevisiae. We describe the latest research, which has established the existence of at least two error-free and two error-prone inter-related mechanisms of damage tolerance that compete for the handling of spontaneous DNA damage. We explore what is known about the induction of mutations by DNA damage. We point to potential paradoxes and to open questions that still remain unanswered.
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Affiliation(s)
- Matan Arbel
- The Shmunis School of Biomedicine and Cancer Research, Tel Aviv University, Ramat Aviv 69978, Israel
| | - Batia Liefshitz
- The Shmunis School of Biomedicine and Cancer Research, Tel Aviv University, Ramat Aviv 69978, Israel
| | - Martin Kupiec
- The Shmunis School of Biomedicine and Cancer Research, Tel Aviv University, Ramat Aviv 69978, Israel
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11
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Su J, Xu R, Mongia P, Toyofuku N, Nakagawa T. Fission yeast Rad8/HLTF facilitates Rad52-dependent chromosomal rearrangements through PCNA lysine 107 ubiquitination. PLoS Genet 2021; 17:e1009671. [PMID: 34292936 PMCID: PMC8297803 DOI: 10.1371/journal.pgen.1009671] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Accepted: 06/18/2021] [Indexed: 11/19/2022] Open
Abstract
Gross chromosomal rearrangements (GCRs), including translocation, deletion, and inversion, can cause cell death and genetic diseases such as cancer in multicellular organisms. Rad51, a DNA strand exchange protein, suppresses GCRs by repairing spontaneous DNA damage through a conservative way of homologous recombination, gene conversion. On the other hand, Rad52 that catalyzes single-strand annealing (SSA) causes GCRs using homologous sequences. However, the detailed mechanism of Rad52-dependent GCRs remains unclear. Here, we provide genetic evidence that fission yeast Rad8/HLTF facilitates Rad52-dependent GCRs through the ubiquitination of lysine 107 (K107) of PCNA, a DNA sliding clamp. In rad51Δ cells, loss of Rad8 eliminated 75% of the isochromosomes resulting from centromere inverted repeat recombination, showing that Rad8 is essential for the formation of the majority of isochromosomes in rad51Δ cells. Rad8 HIRAN and RING finger mutations reduced GCRs, suggesting that Rad8 facilitates GCRs through 3’ DNA-end binding and ubiquitin ligase activity. Mms2 and Ubc4 but not Ubc13 ubiquitin-conjugating enzymes were required for GCRs. Consistent with this, mutating PCNA K107 rather than the well-studied PCNA K164 reduced GCRs. Rad8-dependent PCNA K107 ubiquitination facilitates Rad52-dependent GCRs, as PCNA K107R, rad8, and rad52 mutations epistatically reduced GCRs. In contrast to GCRs, PCNA K107R did not significantly change gene conversion rates, suggesting a specific role of PCNA K107 ubiquitination in GCRs. PCNA K107R enhanced temperature-sensitive growth defects of DNA ligase I cdc17-K42 mutant, implying that PCNA K107 ubiquitination occurs when Okazaki fragment maturation fails. Remarkably, K107 is located at the interface between PCNA subunits, and an interface mutation D150E bypassed the requirement of PCNA K107 and Rad8 ubiquitin ligase for GCRs. These data suggest that Rad8-dependent PCNA K107 ubiquitination facilitates Rad52-dependent GCRs by changing the PCNA clamp structure. Gross chromosomal rearrangements (GCRs), including translocation, can alter gene dosage and activity, resulting in genetic diseases such as cancer. However, GCRs can occur by some enzymes, including Rad52 recombinase, and result in chromosomal evolution. Therefore, GCRs are not only pathological but also physiological phenomena from an evolutionary point of view. However, the detailed mechanism of GCRs remains unclear. Here, using fission yeast, we show that the homolog of human HLTF, Rad8 causes GCRs through noncanonical ubiquitination of proliferating cellular nuclear antigen (PCNA) at a lysine 107 (K107). Rad51, a DNA strand exchange protein, suppresses the formation of isochromosomes whose arms mirror each another and chromosomal truncation. We found that, like Rad52, Rad8 is required for isochromosome formation but not chromosomal truncation in rad51Δ cells, showing a specific role of Rad8 in homology-mediated GCRs. Mutations in Rad8 ubiquitin E3 ligase RING finger domain, Mms2-Ubc4 ubiquitin-conjugating enzymes, and PCNA K107 reduced GCRs in rad51Δ cells, suggesting that Rad8-Mms2-Ubc4-dependent PCNA K107 ubiquitination facilitates GCRs. PCNA trimers form a DNA sliding clamp. The K107 residue is located at the PCNA-PCNA interface, and an interface mutation D150E restored GCRs in PCNA K107R mutant cells. This study provides genetic evidence that Rad8-dependent PCNA K107 ubiquitination facilitates GCRs by changing the PCNA clamp structure.
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Affiliation(s)
- Jie Su
- Department of Biological Sciences, Graduate School of Science, Osaka University, Toyonaka, Japan
| | - Ran Xu
- Department of Biological Sciences, Graduate School of Science, Osaka University, Toyonaka, Japan
| | - Piyusha Mongia
- Department of Biological Sciences, Graduate School of Science, Osaka University, Toyonaka, Japan
| | - Naoko Toyofuku
- Department of Biological Sciences, Graduate School of Science, Osaka University, Toyonaka, Japan
| | - Takuro Nakagawa
- Department of Biological Sciences, Graduate School of Science, Osaka University, Toyonaka, Japan
- * E-mail:
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12
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Wong RP, Petriukov K, Ulrich HD. Daughter-strand gaps in DNA replication - substrates of lesion processing and initiators of distress signalling. DNA Repair (Amst) 2021; 105:103163. [PMID: 34186497 DOI: 10.1016/j.dnarep.2021.103163] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 06/18/2021] [Accepted: 06/19/2021] [Indexed: 10/21/2022]
Abstract
Dealing with DNA lesions during genome replication is particularly challenging because damaged replication templates interfere with the progression of the replicative DNA polymerases and thereby endanger the stability of the replisome. A variety of mechanisms for the recovery of replication forks exist, but both bacteria and eukaryotic cells also have the option of continuing replication downstream of the lesion, leaving behind a daughter-strand gap in the newly synthesized DNA. In this review, we address the significance of these single-stranded DNA structures as sites of DNA damage sensing and processing at a distance from ongoing genome replication. We describe the factors controlling the emergence of daughter-strand gaps from stalled replication intermediates, the benefits and risks of their expansion and repair via translesion synthesis or recombination-mediated template switching, and the mechanisms by which they activate local as well as global replication stress signals. Our growing understanding of daughter-strand gaps not only identifies them as targets of fundamental genome maintenance mechanisms, but also suggests that proper control over their activities has important practical implications for treatment strategies and resistance mechanisms in cancer therapy.
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Affiliation(s)
- Ronald P Wong
- Institute of Molecular Biology (IMB) gGmbH, Ackermannweg 4, D - 55128 Mainz, Germany
| | - Kirill Petriukov
- Institute of Molecular Biology (IMB) gGmbH, Ackermannweg 4, D - 55128 Mainz, Germany
| | - Helle D Ulrich
- Institute of Molecular Biology (IMB) gGmbH, Ackermannweg 4, D - 55128 Mainz, Germany.
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13
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DNA-damage tolerance through PCNA ubiquitination and sumoylation. Biochem J 2021; 477:2655-2677. [PMID: 32726436 DOI: 10.1042/bcj20190579] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 07/08/2020] [Accepted: 07/10/2020] [Indexed: 12/12/2022]
Abstract
DNA-damage tolerance (DDT) is employed by eukaryotic cells to bypass replication-blocking lesions induced by DNA-damaging agents. In budding yeast Saccharomyces cerevisiae, DDT is mediated by RAD6 epistatic group genes and the central event for DDT is sequential ubiquitination of proliferating cell nuclear antigen (PCNA), a DNA clamp required for replication and DNA repair. DDT consists of two parallel pathways: error-prone DDT is mediated by PCNA monoubiquitination, which recruits translesion synthesis DNA polymerases to bypass lesions with decreased fidelity; and error-free DDT is mediated by K63-linked polyubiquitination of PCNA at the same residue of monoubiquitination, which facilitates homologous recombination-mediated template switch. Interestingly, the same PCNA residue is also subjected to sumoylation, which leads to inhibition of unwanted recombination at replication forks. All three types of PCNA posttranslational modifications require dedicated conjugating and ligation enzymes, and these enzymes are highly conserved in eukaryotes, from yeast to human.
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14
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Shen M, Dhingra N, Wang Q, Cheng C, Zhu S, Tian X, Yu J, Gong X, Li X, Zhang H, Xu X, Zhai L, Xie M, Gao Y, Deng H, He Y, Niu H, Zhao X, Xiang S. Structural basis for the multi-activity factor Rad5 in replication stress tolerance. Nat Commun 2021; 12:321. [PMID: 33436623 PMCID: PMC7804152 DOI: 10.1038/s41467-020-20538-w] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Accepted: 12/04/2020] [Indexed: 12/17/2022] Open
Abstract
The yeast protein Rad5 and its orthologs in other eukaryotes promote replication stress tolerance and cell survival using their multiple activities, including ubiquitin ligase, replication fork remodeling and DNA lesion targeting activities. Here, we present the crystal structure of a nearly full-length Rad5 protein. The structure shows three distinct, but well-connected, domains required for Rad5’s activities. The spatial arrangement of these domains suggest that different domains can have autonomous activities but also undergo intrinsic coordination. Moreover, our structural, biochemical and cellular studies demonstrate that Rad5’s HIRAN domain mediates interactions with the DNA metabolism maestro factor PCNA and contributes to its poly-ubiquitination, binds to DNA and contributes to the Rad5-catalyzed replication fork regression, defining a new type of HIRAN domains with multiple activities. Our work provides a framework to understand how Rad5 integrates its various activities in replication stress tolerance. Rad5 is a hub connecting three replication stress tolerance pathways. Here, the authors present the 3.3 Å crystal structure of a N-terminal truncated K.lactis Rad5 construct that reveals the spatial arrangement of the HIRAN, Snf2 and RING domains and structure-guided in vitro and in vivo experiments reveal multiple activities of the yeast Rad5 HIRAN domain among them a role in binding PCNA and supporting its ubiquitination.
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Affiliation(s)
- Miaomiao Shen
- Department of Biochemistry and Molecular Biology, Tianjin Medical University, 300070, Tianjin, P. R. China.,Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Tianjin Medical University, 300070, Tianjin, P. R. China.,The province and ministry co-sponsored collaborative innovation center for medical epigenetics, Tianjin Medical University, 300070, Tianjin, P. R. China
| | - Nalini Dhingra
- Molecular Biology Department, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Quan Wang
- Department of Molecular and Cellular Biochemistry, Indiana University Bloomington, Bloomington, IN, 47405, USA
| | - Chen Cheng
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, CAS Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, 201210, Shanghai, P. R. China
| | - Songbiao Zhu
- MOE Key Laboratory of Bioinformatics, Center for Synthetic and Systematic Biology, School of Life Sciences, Tsinghua University, 100084, Beijing, P. R. China
| | - Xiaolin Tian
- MOE Key Laboratory of Bioinformatics, Center for Synthetic and Systematic Biology, School of Life Sciences, Tsinghua University, 100084, Beijing, P. R. China
| | - Jun Yu
- CAS Key Laboratory of Nutrition, Metabolism and Food safety, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 200031, Shanghai, P. R. China
| | - Xiaoxin Gong
- Department of Biochemistry and Molecular Biology, Tianjin Medical University, 300070, Tianjin, P. R. China.,Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Tianjin Medical University, 300070, Tianjin, P. R. China.,The province and ministry co-sponsored collaborative innovation center for medical epigenetics, Tianjin Medical University, 300070, Tianjin, P. R. China
| | - Xuzhichao Li
- Department of Biochemistry and Molecular Biology, Tianjin Medical University, 300070, Tianjin, P. R. China.,Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Tianjin Medical University, 300070, Tianjin, P. R. China.,The province and ministry co-sponsored collaborative innovation center for medical epigenetics, Tianjin Medical University, 300070, Tianjin, P. R. China
| | - Hongwei Zhang
- CAS Key Laboratory of Nutrition, Metabolism and Food safety, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 200031, Shanghai, P. R. China
| | - Xin Xu
- Department of Biochemistry and Molecular Biology, Tianjin Medical University, 300070, Tianjin, P. R. China.,Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Tianjin Medical University, 300070, Tianjin, P. R. China.,The province and ministry co-sponsored collaborative innovation center for medical epigenetics, Tianjin Medical University, 300070, Tianjin, P. R. China
| | - Liting Zhai
- CAS Key Laboratory of Nutrition, Metabolism and Food safety, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 200031, Shanghai, P. R. China
| | - Min Xie
- CAS Key Laboratory of Nutrition, Metabolism and Food safety, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 200031, Shanghai, P. R. China
| | - Ying Gao
- CAS Key Laboratory of Nutrition, Metabolism and Food safety, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 200031, Shanghai, P. R. China
| | - Haiteng Deng
- MOE Key Laboratory of Bioinformatics, Center for Synthetic and Systematic Biology, School of Life Sciences, Tsinghua University, 100084, Beijing, P. R. China
| | - Yongning He
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, CAS Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, 201210, Shanghai, P. R. China
| | - Hengyao Niu
- Department of Molecular and Cellular Biochemistry, Indiana University Bloomington, Bloomington, IN, 47405, USA
| | - Xiaolan Zhao
- Molecular Biology Department, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Song Xiang
- Department of Biochemistry and Molecular Biology, Tianjin Medical University, 300070, Tianjin, P. R. China. .,Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Tianjin Medical University, 300070, Tianjin, P. R. China. .,The province and ministry co-sponsored collaborative innovation center for medical epigenetics, Tianjin Medical University, 300070, Tianjin, P. R. China.
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15
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Takahashi TS, Wollscheid HP, Lowther J, Ulrich HD. Effects of chain length and geometry on the activation of DNA damage bypass by polyubiquitylated PCNA. Nucleic Acids Res 2020; 48:3042-3052. [PMID: 32009145 PMCID: PMC7102961 DOI: 10.1093/nar/gkaa053] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Revised: 01/15/2020] [Accepted: 01/30/2020] [Indexed: 01/06/2023] Open
Abstract
Ubiquitylation of the eukaryotic sliding clamp, PCNA, activates a pathway of DNA damage bypass that facilitates the replication of damaged DNA. In its monoubiquitylated form, PCNA recruits a set of damage-tolerant DNA polymerases for translesion synthesis. Alternatively, modification by K63-linked polyubiquitylation triggers a recombinogenic process involving template switching. Despite the identification of proteins interacting preferentially with polyubiquitylated PCNA, the molecular function of the chain and the relevance of its K63-linkage are poorly understood. Using genetically engineered mimics of polyubiquitylated PCNA, we have now examined the properties of the ubiquitin chain required for damage bypass in budding yeast. By varying key parameters such as the geometry of the junction, cleavability and capacity for branching, we demonstrate that either the structure of the ubiquitin-ubiquitin junction or its dynamic assembly or disassembly at the site of action exert a critical impact on damage bypass, even though known effectors of polyubiquitylated PCNA are not strictly linkage-selective. Moreover, we found that a single K63-junction supports substantial template switching activity, irrespective of its attachment site on PCNA. Our findings provide insight into the interrelationship between the two branches of damage bypass and suggest the existence of a yet unidentified, highly linkage-selective receptor of polyubiquitylated PCNA.
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Affiliation(s)
- Tomio S Takahashi
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, 91198, Gif-sur-Yvette cedex, France
| | | | | | - Helle D Ulrich
- Institute of Molecular Biology gGmbH (IMB), Ackermannweg 4, D-55128 Mainz, Germany
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16
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Shin S, Hyun K, Kim J, Hohng S. ATP Binding to Rad5 Initiates Replication Fork Reversal by Inducing the Unwinding of the Leading Arm and the Formation of the Holliday Junction. Cell Rep 2019; 23:1831-1839. [PMID: 29742437 DOI: 10.1016/j.celrep.2018.04.029] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 02/20/2018] [Accepted: 04/05/2018] [Indexed: 11/30/2022] Open
Abstract
Replication fork reversal is one of the major pathways for reactivating stalled DNA replication. Many enzymes with replication fork reversal activity have DNA-unwinding activity as well, but none of the fork reversal enzymes in the SWI/SNF family shows a separate DNA-unwinding activity, raising the question of how they initiate the remodeling process. Here, we found ATP binding to Rad5 induces the unwinding of the leading arm of the replication fork and proximally positions the leading and lagging arms. This facilitates the spontaneous remodeling of the replication fork into a four-way junction. Once the four-way junction is formed, Rad5 migrates the four-way junction at a speed of 7.1 ± 0.14 nt/s. The 3' end anchoring of the leading arm by Rad5's HIRAN domain is critical for both branch migration and the recovery of the three-way junction, but not for the structural transition to the four-way junction.
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Affiliation(s)
- Soochul Shin
- Department of Physics and Astronomy, Institute of Applied Physics, National Center of Creative Research Initiatives, Seoul National University, Seoul 08826, Republic of Korea
| | - Kwangbeom Hyun
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
| | - Jaehoon Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea.
| | - Sungchul Hohng
- Department of Physics and Astronomy, Institute of Applied Physics, National Center of Creative Research Initiatives, Seoul National University, Seoul 08826, Republic of Korea.
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17
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García-Rodríguez N, Wong RP, Ulrich HD. The helicase Pif1 functions in the template switching pathway of DNA damage bypass. Nucleic Acids Res 2019; 46:8347-8356. [PMID: 30107417 PMCID: PMC6144865 DOI: 10.1093/nar/gky648] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Accepted: 08/08/2018] [Indexed: 11/13/2022] Open
Abstract
Replication of damaged DNA is challenging because lesions in the replication template frequently interfere with an orderly progression of the replisome. In this situation, complete duplication of the genome is ensured by the action of DNA damage bypass pathways effecting either translesion synthesis by specialized, damage-tolerant DNA polymerases or a recombination-like mechanism called template switching (TS). Here we report that budding yeast Pif1, a helicase known to be involved in the resolution of complex DNA structures as well as the maturation of Okazaki fragments during replication, contributes to DNA damage bypass. We show that Pif1 expands regions of single-stranded DNA, so-called daughter-strand gaps, left behind the replication fork as a consequence of replisome re-priming. This function requires interaction with the replication clamp, proliferating cell nuclear antigen, facilitating its recruitment to damage sites, and complements the activity of an exonuclease, Exo1, in the processing of post-replicative daughter-strand gaps in preparation for TS. Our results thus reveal a novel function of a conserved DNA helicase that is known as a key player in genome maintenance.
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Affiliation(s)
| | - Ronald P Wong
- Institute of Molecular Biology (IMB), Ackermannweg 4, D-55128 Mainz, Germany
| | - Helle D Ulrich
- Institute of Molecular Biology (IMB), Ackermannweg 4, D-55128 Mainz, Germany
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18
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Masuda Y, Mitsuyuki S, Kanao R, Hishiki A, Hashimoto H, Masutani C. Regulation of HLTF-mediated PCNA polyubiquitination by RFC and PCNA monoubiquitination levels determines choice of damage tolerance pathway. Nucleic Acids Res 2019; 46:11340-11356. [PMID: 30335157 PMCID: PMC6265450 DOI: 10.1093/nar/gky943] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Accepted: 10/04/2018] [Indexed: 12/16/2022] Open
Abstract
DNA-damage tolerance protects cells via at least two sub-pathways regulated by proliferating cell nuclear antigen (PCNA) ubiquitination in eukaryotes: translesion DNA synthesis (TLS) and template switching (TS), which are stimulated by mono- and polyubiquitination, respectively. However, how cells choose between the two pathways remains unclear. The regulation of ubiquitin ligases catalyzing polyubiquitination, such as helicase-like transcription factor (HLTF), could play a role in the choice of pathway. Here, we demonstrate that the ligase activity of HLTF is stimulated by double-stranded DNA via HIRAN domain-dependent recruitment to stalled primer ends. Replication factor C (RFC) and PCNA located at primer ends, however, suppress en bloc polyubiquitination in the complex, redirecting toward sequential chain elongation. When PCNA in the complex is monoubiquitinated by RAD6-RAD18, the resulting ubiquitin moiety is immediately polyubiquitinated by coexisting HLTF, indicating a coupling reaction between mono- and polyubiquitination. By contrast, when PCNA was monoubiquitinated in the absence of HLTF, it was not polyubiquitinated by subsequently recruited HLTF unless all three-subunits of PCNA were monoubiquitinated, indicating that the uncoupling reaction specifically occurs on three-subunit-monoubiquitinated PCNA. We discuss the physiological relevance of the different modes of the polyubiquitination to the choice of cells between TLS and TS under different conditions.
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Affiliation(s)
- Yuji Masuda
- Department of Genome Dynamics, Research Institute of Environmental Medicine, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan.,Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550, Japan
| | - Satoshi Mitsuyuki
- Department of Genome Dynamics, Research Institute of Environmental Medicine, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan.,Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550, Japan
| | - Rie Kanao
- Department of Genome Dynamics, Research Institute of Environmental Medicine, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan.,Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550, Japan
| | - Asami Hishiki
- School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8002, Japan
| | - Hiroshi Hashimoto
- School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8002, Japan
| | - Chikahide Masutani
- Department of Genome Dynamics, Research Institute of Environmental Medicine, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan.,Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550, Japan
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19
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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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20
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Gallo D, Brown GW. Post-replication repair: Rad5/HLTF regulation, activity on undamaged templates, and relationship to cancer. Crit Rev Biochem Mol Biol 2019; 54:301-332. [PMID: 31429594 DOI: 10.1080/10409238.2019.1651817] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Revised: 07/12/2019] [Accepted: 07/31/2019] [Indexed: 12/18/2022]
Abstract
The eukaryotic post-replication repair (PRR) pathway allows completion of DNA replication when replication forks encounter lesions on the DNA template and are mediated by post-translational ubiquitination of the DNA sliding clamp proliferating cell nuclear antigen (PCNA). Monoubiquitinated PCNA recruits translesion synthesis (TLS) polymerases to replicate past DNA lesions in an error-prone manner while addition of K63-linked polyubiquitin chains signals for error-free template switching to the sister chromatid. Central to both branches is the E3 ubiquitin ligase and DNA helicase Rad5/helicase-like transcription factor (HLTF). Mutations in PRR pathway components lead to genomic rearrangements, cancer predisposition, and cancer progression. Recent studies have challenged the notion that the PRR pathway is involved only in DNA lesion tolerance and have shed new light on its roles in cancer progression. Molecular details of Rad5/HLTF recruitment and function at replication forks have emerged. Mounting evidence indicates that PRR is required during lesion-less replication stress, leading to TLS polymerase activity on undamaged templates. Analysis of PRR mutation status in human cancers and PRR function in cancer models indicates that down regulation of PRR activity is a viable strategy to inhibit cancer cell growth and reduce chemoresistance. Here, we review these findings, discuss how they change our views of current PRR models, and look forward to targeting the PRR pathway in the clinic.
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Affiliation(s)
- David Gallo
- Department of Biochemistry and Donnelly Centre, University of Toronto , Toronto , Canada
| | - Grant W Brown
- Department of Biochemistry and Donnelly Centre, University of Toronto , Toronto , Canada
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21
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Gallo D, Kim T, Szakal B, Saayman X, Narula A, Park Y, Branzei D, Zhang Z, Brown GW. Rad5 Recruits Error-Prone DNA Polymerases for Mutagenic Repair of ssDNA Gaps on Undamaged Templates. Mol Cell 2019; 73:900-914.e9. [PMID: 30733119 DOI: 10.1016/j.molcel.2019.01.001] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2018] [Revised: 09/13/2018] [Accepted: 12/27/2018] [Indexed: 12/30/2022]
Abstract
Post-replication repair (PRR) allows tolerance of chemical- and UV-induced DNA base lesions in both an error-free and an error-prone manner. In classical PRR, PCNA monoubiquitination recruits translesion synthesis (TLS) DNA polymerases that can replicate through lesions. We find that PRR responds to DNA replication stress that does not cause base lesions. Rad5 forms nuclear foci during normal S phase and after exposure to types of replication stress where DNA base lesions are likely absent. Rad5 binds to the sites of stressed DNA replication forks, where it recruits TLS polymerases to repair single-stranded DNA (ssDNA) gaps, preventing mitotic defects and chromosome breaks. In contrast to the prevailing view of PRR, our data indicate that Rad5 promotes both mutagenic and error-free repair of undamaged ssDNA that arises during physiological and exogenous replication stress.
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Affiliation(s)
- David Gallo
- Department of Biochemistry, University of Toronto, 1 King's College Circle, Toronto, ON M5S 3E1, Canada; Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON M5S 3E1, Canada
| | - TaeHyung Kim
- Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON M5S 3E1, Canada; Department of Computer Science, University of Toronto, 1 King's College Circle, Toronto, ON M5S 3E1, Canada
| | - Barnabas Szakal
- IFOM, Fondazione Istituto FIRC di Oncologia Molecolare, Via Adamello 16, 20139 Milan, Italy
| | - Xanita Saayman
- Department of Biochemistry, University of Toronto, 1 King's College Circle, Toronto, ON M5S 3E1, Canada; Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON M5S 3E1, Canada
| | - Ashrut Narula
- Department of Biochemistry, University of Toronto, 1 King's College Circle, Toronto, ON M5S 3E1, Canada; Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON M5S 3E1, Canada
| | - Yoona Park
- Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON M5S 3E1, Canada; Department of Computer Science, University of Toronto, 1 King's College Circle, Toronto, ON M5S 3E1, Canada
| | - Dana Branzei
- IFOM, Fondazione Istituto FIRC di Oncologia Molecolare, Via Adamello 16, 20139 Milan, Italy; Istituto di Genetica Molecolare, Consiglio Nazionale delle Ricerche (IGM-CNR), Via Abbiategrasso 207, 27100 Pavia, Italy
| | - Zhaolei Zhang
- Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON M5S 3E1, Canada; Department of Computer Science, University of Toronto, 1 King's College Circle, Toronto, ON M5S 3E1, Canada
| | - Grant W Brown
- Department of Biochemistry, University of Toronto, 1 King's College Circle, Toronto, ON M5S 3E1, Canada; Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON M5S 3E1, Canada.
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22
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Prado F. Homologous Recombination: To Fork and Beyond. Genes (Basel) 2018; 9:genes9120603. [PMID: 30518053 PMCID: PMC6316604 DOI: 10.3390/genes9120603] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 11/29/2018] [Accepted: 11/29/2018] [Indexed: 12/15/2022] Open
Abstract
Accurate completion of genome duplication is threatened by multiple factors that hamper the advance and stability of the replication forks. Cells need to tolerate many of these blocking lesions to timely complete DNA replication, postponing their repair for later. This process of lesion bypass during DNA damage tolerance can lead to the accumulation of single-strand DNA (ssDNA) fragments behind the fork, which have to be filled in before chromosome segregation. Homologous recombination plays essential roles both at and behind the fork, through fork protection/lesion bypass and post-replicative ssDNA filling processes, respectively. I review here our current knowledge about the recombination mechanisms that operate at and behind the fork in eukaryotes, and how these mechanisms are controlled to prevent unscheduled and toxic recombination intermediates. A unifying model to integrate these mechanisms in a dynamic, replication fork-associated process is proposed from yeast results.
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Affiliation(s)
- Félix Prado
- Department of Genome Biology, Andalusian Molecular Biology and Regenerative Medicine Center (CABIMER), CSIC-University of Seville-University Pablo de Olavide, 41092 Seville, Spain.
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23
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Hayashi M, Keyamura K, Hishida T. Cyclin-dependent kinase modulates budding yeast Rad5 stability during cell cycle. PLoS One 2018; 13:e0204680. [PMID: 30256854 PMCID: PMC6157869 DOI: 10.1371/journal.pone.0204680] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Accepted: 09/12/2018] [Indexed: 12/12/2022] Open
Abstract
The DNA damage tolerance (DDT) pathway facilitates the bypass of the fork-blocking lesions without removing them through either translesion DNA synthesis or error-free damage bypass mechanism. The Saccharomyces cerevisiae Rad5 is a multi-functional protein involved in the error-free branch of the DDT pathway, and its protein level periodically fluctuates through the cell cycle; however, the mechanistic basis and functional importance of the Rad5 level for the cell cycle regulation remain unclear. Here, we show that Rad5 is predominantly phosphorylated on serine 130 (S130) during S/G2 phase and that this modification depends on the cyclin-dependent kinase Cdc28/CDK1. We also show that the phosphorylated Rad5 species at S130 exhibit a relatively short half-life compared with non-phosphorylated Rad5 moiety, and that the Rad5 protein is partially stabilized in phosphorylation-defective rad5 S130A cells. Importantly, the elimination of this modification results in a defective cell-cycle dependent Rad5 oscillation pattern. Together, our results demonstrate that CDK1 modulates Rad5 stability by phosphorylation during the cell cycle, suggesting a crosstalk between the phosphorylation and degradation of Rad5.
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Affiliation(s)
- Masafumi Hayashi
- Department of Life Science, Graduate School of Science, Gakushuin University, Tokyo, Japan
| | - Kenji Keyamura
- Department of Life Science, Graduate School of Science, Gakushuin University, Tokyo, Japan
| | - Takashi Hishida
- Department of Life Science, Graduate School of Science, Gakushuin University, Tokyo, Japan
- * E-mail:
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24
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Díaz-Mejía JJ, Celaj A, Mellor JC, Coté A, Balint A, Ho B, Bansal P, Shaeri F, Gebbia M, Weile J, Verby M, Karkhanina A, Zhang Y, Wong C, Rich J, Prendergast D, Gupta G, Öztürk S, Durocher D, Brown GW, Roth FP. Mapping DNA damage-dependent genetic interactions in yeast via party mating and barcode fusion genetics. Mol Syst Biol 2018; 14:e7985. [PMID: 29807908 PMCID: PMC5974512 DOI: 10.15252/msb.20177985] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Condition‐dependent genetic interactions can reveal functional relationships between genes that are not evident under standard culture conditions. State‐of‐the‐art yeast genetic interaction mapping, which relies on robotic manipulation of arrays of double‐mutant strains, does not scale readily to multi‐condition studies. Here, we describe barcode fusion genetics to map genetic interactions (BFG‐GI), by which double‐mutant strains generated via en masse “party” mating can also be monitored en masse for growth to detect genetic interactions. By using site‐specific recombination to fuse two DNA barcodes, each representing a specific gene deletion, BFG‐GI enables multiplexed quantitative tracking of double mutants via next‐generation sequencing. We applied BFG‐GI to a matrix of DNA repair genes under nine different conditions, including methyl methanesulfonate (MMS), 4‐nitroquinoline 1‐oxide (4NQO), bleomycin, zeocin, and three other DNA‐damaging environments. BFG‐GI recapitulated known genetic interactions and yielded new condition‐dependent genetic interactions. We validated and further explored a subnetwork of condition‐dependent genetic interactions involving MAG1,SLX4, and genes encoding the Shu complex, and inferred that loss of the Shu complex leads to an increase in the activation of the checkpoint protein kinase Rad53.
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Affiliation(s)
- J Javier Díaz-Mejía
- Donnelly Centre, University of Toronto, Toronto, ON, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada.,Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, Toronto, ON, Canada.,Department of Computer Science, University of Toronto, Toronto, ON, Canada
| | - Albi Celaj
- Donnelly Centre, University of Toronto, Toronto, ON, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada.,Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, Toronto, ON, Canada.,Department of Computer Science, University of Toronto, Toronto, ON, Canada
| | - Joseph C Mellor
- Donnelly Centre, University of Toronto, Toronto, ON, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada.,Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, Toronto, ON, Canada.,Department of Computer Science, University of Toronto, Toronto, ON, Canada.,Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, USA
| | - Atina Coté
- Donnelly Centre, University of Toronto, Toronto, ON, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada.,Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, Toronto, ON, Canada
| | - Attila Balint
- Donnelly Centre, University of Toronto, Toronto, ON, Canada.,Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Brandon Ho
- Donnelly Centre, University of Toronto, Toronto, ON, Canada.,Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Pritpal Bansal
- Donnelly Centre, University of Toronto, Toronto, ON, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada.,Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, Toronto, ON, Canada
| | - Fatemeh Shaeri
- Donnelly Centre, University of Toronto, Toronto, ON, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada.,Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, Toronto, ON, Canada
| | - Marinella Gebbia
- Donnelly Centre, University of Toronto, Toronto, ON, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Jochen Weile
- Donnelly Centre, University of Toronto, Toronto, ON, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada.,Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, Toronto, ON, Canada
| | - Marta Verby
- Donnelly Centre, University of Toronto, Toronto, ON, Canada.,Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, Toronto, ON, Canada
| | - Anna Karkhanina
- Donnelly Centre, University of Toronto, Toronto, ON, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada.,Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, Toronto, ON, Canada
| | - YiFan Zhang
- Donnelly Centre, University of Toronto, Toronto, ON, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada.,Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, Toronto, ON, Canada
| | - Cassandra Wong
- Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, Toronto, ON, Canada
| | - Justin Rich
- Donnelly Centre, University of Toronto, Toronto, ON, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada.,Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, Toronto, ON, Canada
| | - D'Arcy Prendergast
- Donnelly Centre, University of Toronto, Toronto, ON, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada.,Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, Toronto, ON, Canada
| | - Gaurav Gupta
- Donnelly Centre, University of Toronto, Toronto, ON, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada.,Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, Toronto, ON, Canada
| | - Sedide Öztürk
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, USA
| | - Daniel Durocher
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada.,Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, Toronto, ON, Canada
| | - Grant W Brown
- Donnelly Centre, University of Toronto, Toronto, ON, Canada.,Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Frederick P Roth
- Donnelly Centre, University of Toronto, Toronto, ON, Canada .,Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada.,Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, Toronto, ON, Canada.,Department of Computer Science, University of Toronto, Toronto, ON, Canada.,Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, USA.,Center for Cancer Systems Biology (CCSB) and Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA, USA.,Canadian Institute for Advanced Research, Toronto, ON, Canada
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25
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Chavez DA, Greer BH, Eichman BF. The HIRAN domain of helicase-like transcription factor positions the DNA translocase motor to drive efficient DNA fork regression. J Biol Chem 2018; 293:8484-8494. [PMID: 29643183 DOI: 10.1074/jbc.ra118.002905] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Revised: 04/09/2018] [Indexed: 11/06/2022] Open
Abstract
Helicase-like transcription factor (HLTF) is a central mediator of the DNA damage response and maintains genome stability by regressing stalled replication forks. The N-terminal HIRAN domain binds specifically to the 3'-end of single-stranded DNA (ssDNA), and disrupting this function interferes with fork regression in vitro as well as replication fork progression in cells under replication stress. Here, we investigated the mechanism by which the HIRAN-ssDNA interaction facilitates fork remodeling. Our results indicated that HIRAN capture of a denatured nascent leading 3'-end directs specific binding of HLTF to forks. DNase footprinting revealed that HLTF binds to the parental duplex ahead of the fork and at the leading edge behind the fork. Moreover, we found that the HIRAN domain is important for initiating regression of forks when both nascent strands are at the junction, but is dispensable when forks contain ssDNA regions on either template strand. We also found that HLTF catalyzes fork restoration from a partially regressed structure in a HIRAN-dependent manner. Thus, HIRAN serves as a substrate-recognition domain to properly orient the ATPase motor domain at stalled and regressed forks and initiates fork remodeling by guiding formation of a four-way junction. We discuss how these activities compare with those of two related fork remodelers, SWI/SNF-related, matrix-associated, actin-dependent regulator of chromatin, subfamily A-like 1 (SMARCAL1) and zinc finger RANBP2 type-containing 3 (ZRANB3) to provide insight into their nonredundant roles in DNA damage tolerance.
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Affiliation(s)
| | | | - Brandt F Eichman
- From the Department of Biological Sciences and .,Department of Biochemistry, Vanderbilt University, Nashville, Tennessee 37232
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26
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Abstract
One major challenge during genome duplication is the stalling of DNA replication forks by various forms of template blockages. As these barriers can lead to incomplete replication, multiple mechanisms have to act concertedly to correct and rescue stalled replication forks. Among these mechanisms, replication fork regression entails simultaneous annealing of nascent and template strands, which leads to regression of replication forks and formation of four-way DNA junctions. In principle, this process can lead to either positive outcomes, such as DNA repair and replication resumption, or less desirable outcomes, such as misalignment between nascent and template DNA and DNA cleavage. While our understanding of replication fork regression and its various possible outcomes is still at an early stage, recent studies using combinational approaches in multiple organisms have begun to identify the enzymes that catalyze this DNA transaction and how these enzymes are regulated, as well as the specific manners by which fork regression can influence replication. This review summarizes these recent progresses. In keeping with the theme of this series of reviews, we focus on studies in yeast and compare to findings in higher eukaryotes. It is anticipated that these findings will form the basis for future endeavors to further elucidate replication fork remodeling and its implications for genome maintenance.
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27
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Klemm T, Mannuß A, Kobbe D, Knoll A, Trapp O, Dorn A, Puchta H. The DNA translocase RAD5A acts independently of the other main DNA repair pathways, and requires both its ATPase and RING domain for activity in Arabidopsis thaliana. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2017; 91:725-740. [PMID: 28509359 DOI: 10.1111/tpj.13602] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Revised: 04/27/2017] [Accepted: 05/09/2017] [Indexed: 06/07/2023]
Abstract
Multiple pathways exist to repair DNA damage induced by methylating and crosslinking agents in Arabidopsis thaliana. The SWI2/SNF2 translocase RAD5A, the functional homolog of budding yeast Rad5 that is required for the error-free branch of post-replicative repair, plays a surprisingly prominent role in the repair of both kinds of lesions in Arabidopsis. Here we show that both the ATPase domain and the ubiquitination function of the RING domain of the Arabidopsis protein are essential for the cellular response to different forms of DNA damage. To define the exact role of RAD5A within the complex network of DNA repair pathways, we crossed the rad5a mutant line with mutants of different known repair factors of Arabidopsis. We had previously shown that RAD5A acts independently of two main pathways of replication-associated DNA repair defined by the helicase RECQ4A and the endonuclease MUS81. The enhanced sensitivity of all double mutants tested in this study indicates that the repair of damaged DNA by RAD5A also occurs independently of nucleotide excision repair (AtRAD1), single-strand break repair (AtPARP1), as well as microhomology-mediated double-strand break repair (AtTEB). Moreover, RAD5A can partially complement for a deficient AtATM-mediated DNA damage response in plants, as the double mutant shows phenotypic growth defects.
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Affiliation(s)
- Tobias Klemm
- Botanical Institute, Karlsruhe Institute of Technology, Kaiserstr. 12, 76131, Karlsruhe, Germany
| | | | - Daniela Kobbe
- Botanical Institute, Karlsruhe Institute of Technology, Kaiserstr. 12, 76131, Karlsruhe, Germany
| | - Alexander Knoll
- Botanical Institute, Karlsruhe Institute of Technology, Kaiserstr. 12, 76131, Karlsruhe, Germany
| | | | - Annika Dorn
- Botanical Institute, Karlsruhe Institute of Technology, Kaiserstr. 12, 76131, Karlsruhe, Germany
| | - Holger Puchta
- Botanical Institute, Karlsruhe Institute of Technology, Kaiserstr. 12, 76131, Karlsruhe, Germany
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28
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Jalal D, Chalissery J, Hassan AH. Genome maintenance in Saccharomyces cerevisiae: the role of SUMO and SUMO-targeted ubiquitin ligases. Nucleic Acids Res 2017; 45:2242-2261. [PMID: 28115630 PMCID: PMC5389695 DOI: 10.1093/nar/gkw1369] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Accepted: 01/02/2017] [Indexed: 01/08/2023] Open
Abstract
The genome of the cell is often exposed to DNA damaging agents and therefore requires an intricate well-regulated DNA damage response (DDR) to overcome its deleterious effects. The DDR needs proper regulation for its timely activation, repression, as well as appropriate choice of repair pathway. Studies in Saccharomyces cerevisiae have advanced our understanding of the DNA damage response, as well as the mechanisms the cell employs to maintain genome stability and how these mechanisms are regulated. Eukaryotic cells utilize post-translational modifications as a means for fine-tuning protein functions. Ubiquitylation and SUMOylation involve the attachment of small protein molecules onto proteins to modulate function or protein–protein interactions. SUMO in particular, was shown to act as a molecular glue when DNA damage occurs, facilitating the assembly of large protein complexes in repair foci. In other instances, SUMOylation alters a protein's biochemical activities, and interactions. SUMO-targeted ubiquitin ligases (STUbLs) are enzymes that target SUMOylated proteins for ubiquitylation and subsequent degradation, providing a function for the SUMO modification in the regulation and disassembly of repair complexes. Here, we discuss the major contributions of SUMO and STUbLs in the regulation of DNA damage repair pathways as well as in the maintenance of critical regions of the genome, namely rDNA regions, telomeres and the 2 μm circle in budding yeast.
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Affiliation(s)
- Deena Jalal
- Department of Biochemistry, College of Medicine and Health Sciences, United Arab Emirates University, P.O. Box 17666, Al-Ain, UAE
| | - Jisha Chalissery
- Department of Biochemistry, College of Medicine and Health Sciences, United Arab Emirates University, P.O. Box 17666, Al-Ain, UAE
| | - Ahmed H Hassan
- Department of Biochemistry, College of Medicine and Health Sciences, United Arab Emirates University, P.O. Box 17666, Al-Ain, UAE
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29
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Fasullo MT, Sun M. Both RAD5-dependent and independent pathways are involved in DNA damage-associated sister chromatid exchange in budding yeast. AIMS GENETICS 2017; 4:84-102. [PMID: 28596989 PMCID: PMC5460634 DOI: 10.3934/genet.2017.2.84] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Sister chromatids are preferred substrates for recombinational repair after cells are exposed to DNA damage. While some agents directly cause double-strand breaks (DSBs), others form DNA base adducts which stall or impede the DNA replication fork. We asked which types of DNA damage can stimulate SCE in budding yeast mutants defective in template switch mechanisms and whether PCNA polyubiquitination functions are required for DNA damage-associated SCE after exposure to potent recombinagens. We measured spontaneous and DNA damage-associated unequal sister chromatid exchange (uSCE) in yeast strains containing two fragments of his3 after exposure to MMS, 4-NQO, UV, X rays, and HO endonuclease-induced DSBs. We determined whether other genes in the pathway for template switching, including UBC13, MMS2, SGS1, and SRS2 were required for DNA damage-associated SCE. RAD5 was required for DNA damage-associated SCE after exposure to UV, MMS, and 4-NQO, but not for spontaneous, X-ray-associated, or HO endonuclease-induced SCE. While UBC13, MMS2, and SGS1 were required for MMS and 4NQO-associated SCE, they were not required for UV-associated SCE. DNA damage-associated recombination between his3 recombination substrates on non-homologous recombination was enhanced in rad5 mutants. These results demonstrate that DNA damaging agents that cause DSBs stimulate SCE by RAD5-independent mechanisms, while several potent agents that generate bulky DNA adducts stimulate SCE by multiple RAD5-dependent mechanisms. We suggest that DSB-associated recombination that occurs in G2 is RAD5-independent.
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Affiliation(s)
- Michael T Fasullo
- College of Nanoscale Sciences and Engineering, SUNY Polytechnic Institute, 257 Fuller Road, Albany, New York 12203, United States
| | - Mingzeng Sun
- College of Nanoscale Sciences and Engineering, SUNY Polytechnic Institute, 257 Fuller Road, Albany, New York 12203, United States
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30
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Monoubiquitylation of histone H2B contributes to the bypass of DNA damage during and after DNA replication. Proc Natl Acad Sci U S A 2017; 114:E2205-E2214. [PMID: 28246327 PMCID: PMC5358361 DOI: 10.1073/pnas.1612633114] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
DNA lesion bypass is mediated by DNA damage tolerance (DDT) pathways and homologous recombination (HR). The DDT pathways, which involve translesion synthesis and template switching (TS), are activated by the ubiquitylation (ub) of PCNA through components of the RAD6-RAD18 pathway, whereas the HR pathway is independent of RAD18 However, it is unclear how these processes are coordinated within the context of chromatin. Here we show that Bre1, an ubiquitin ligase specific for histone H2B, is recruited to chromatin in a manner coupled to replication of damaged DNA. In the absence of Bre1 or H2Bub, cells exhibit accumulation of unrepaired DNA lesions. Consequently, the damaged forks become unstable and resistant to repair. We provide physical, genetic, and cytological evidence that H2Bub contributes toward both Rad18-dependent TS and replication fork repair by HR. Using an inducible system of DNA damage bypass, we further show that H2Bub is required for the regulation of DDT after genome duplication. We propose that Bre1-H2Bub facilitates fork recovery and gap-filling repair by controlling chromatin dynamics in response to replicative DNA damage.
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31
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Syed S, Desler C, Rasmussen LJ, Schmidt KH. A Novel Rrm3 Function in Restricting DNA Replication via an Orc5-Binding Domain Is Genetically Separable from Rrm3 Function as an ATPase/Helicase in Facilitating Fork Progression. PLoS Genet 2016; 12:e1006451. [PMID: 27923055 PMCID: PMC5140057 DOI: 10.1371/journal.pgen.1006451] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2016] [Accepted: 10/31/2016] [Indexed: 11/21/2022] Open
Abstract
In response to replication stress cells activate the intra-S checkpoint, induce DNA repair pathways, increase nucleotide levels, and inhibit origin firing. Here, we report that Rrm3 associates with a subset of replication origins and controls DNA synthesis during replication stress. The N-terminal domain required for control of DNA synthesis maps to residues 186–212 that are also critical for binding Orc5 of the origin recognition complex. Deletion of this domain is lethal to cells lacking the replication checkpoint mediator Mrc1 and leads to mutations upon exposure to the replication stressor hydroxyurea. This novel Rrm3 function is independent of its established role as an ATPase/helicase in facilitating replication fork progression through polymerase blocking obstacles. Using quantitative mass spectrometry and genetic analyses, we find that the homologous recombination factor Rdh54 and Rad5-dependent error-free DNA damage bypass act as independent mechanisms on DNA lesions that arise when Rrm3 catalytic activity is disrupted whereas these mechanisms are dispensable for DNA damage tolerance when the replication function is disrupted, indicating that the DNA lesions generated by the loss of each Rrm3 function are distinct. Although both lesion types activate the DNA-damage checkpoint, we find that the resultant increase in nucleotide levels is not sufficient for continued DNA synthesis under replication stress. Together, our findings suggest a role of Rrm3, via its Orc5-binding domain, in restricting DNA synthesis that is genetically and physically separable from its established catalytic role in facilitating fork progression through replication blocks. When cells duplicate their genome, the replication machinery is constantly at risk of encountering obstacles, including unusual DNA structures, bound proteins, or transcribing polymerases and transcripts. Cells possess DNA helicases that facilitate movement of the replication fork through such obstacles. Here, we report the discovery that one of these DNA helicases, Rrm3, is also required for restricting DNA synthesis under replication stress. We find that the site in Rrm3 critical for this new replication function is also required for binding a subunit of the replication origin recognition complex, which raises the possibility that Rrm3 controls replication by affecting initiation. This is supported by our finding that Rrm3 associates with a subset of replication origins. Rrm3’s ability to restrict replication does not require its helicase activity or the phosphorylation site that regulates this activity. Notably, cells need error-free bypass pathways and homologous recombination to deal with DNA lesions that arise when the helicase function of Rrm3 is disrupted, but not when its replication function is disrupted. This indicates that the DNA lesions that form in the absence of the two distinct Rrm3 function are different, although both activate the DNA-damage checkpoint and are toxic to cells that lack the mediator of the replication checkpoint Mrc1.
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Affiliation(s)
- Salahuddin Syed
- Department of Cell Biology, Microbiology, and Molecular Biology, University of South Florida, Tampa, Florida, United States of America
- Graduate Program in Cellular and Molecular Biology, University of South Florida, Tampa, Florida, United States of America
| | - Claus Desler
- Center for Healthy Aging, Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Lene J. Rasmussen
- Center for Healthy Aging, Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Kristina H. Schmidt
- Department of Cell Biology, Microbiology, and Molecular Biology, University of South Florida, Tampa, Florida, United States of America
- Cancer Biology and Evolution Program, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida, United States of America
- * E-mail:
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32
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Kobbe D, Kahles A, Walter M, Klemm T, Mannuss A, Knoll A, Focke M, Puchta H. AtRAD5A is a DNA translocase harboring a HIRAN domain which confers binding to branched DNA structures and is required for DNA repair in vivo. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2016; 88:521-530. [PMID: 27458713 DOI: 10.1111/tpj.13283] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Revised: 07/20/2016] [Accepted: 07/22/2016] [Indexed: 05/26/2023]
Abstract
DNA lesions such as crosslinks represent obstacles for the replication machinery. Nonetheless, replication can proceed via the DNA damage tolerance pathway also known as postreplicative repair pathway. SNF2 ATPase Rad5 homologs, such as RAD5A of the model plant Arabidopsis thaliana, are important for the error-free mode of this pathway. We able to demonstrate before, that RAD5A is a key factor in the repair of DNA crosslinks in Arabidopsis. Here, we show by in vitro analysis that AtRAD5A protein is a DNA translocase able to catalyse fork regression. Interestingly, replication forks with a gap in the leading strand are processed best, in line with its suggested function. Furthermore AtRAD5A catalyses branch migration of a Holliday junction and is furthermore not impaired by the DNA binding of a model protein, which is indicative of its ability to displace other proteins. Rad5 homologs possess HIRAN (Hip116, Rad5; N-terminal) domains. By biochemical analysis we were able to demonstrate that the HIRAN domain variant from Arabidopsis RAD5A mediates structure selective DNA binding without the necessity for a free 3'OH group as has been shown to be required for binding of HIRAN domains in a mammalian RAD5 homolog. The biological importance of the HIRAN domain in AtRAD5A is demonstrated by our result that it is required for its function in DNA crosslink repair in vivo.
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Affiliation(s)
- Daniela Kobbe
- Botanical Institute II, Karlsruhe Institute of Technology (KIT), Karlsruhe, 76131, Germany
| | - Andy Kahles
- Botanical Institute II, Karlsruhe Institute of Technology (KIT), Karlsruhe, 76131, Germany
| | - Maria Walter
- Botanical Institute II, Karlsruhe Institute of Technology (KIT), Karlsruhe, 76131, Germany
| | - Tobias Klemm
- Botanical Institute II, Karlsruhe Institute of Technology (KIT), Karlsruhe, 76131, Germany
| | - Anja Mannuss
- Botanical Institute II, Karlsruhe Institute of Technology (KIT), Karlsruhe, 76131, Germany
| | - Alexander Knoll
- Botanical Institute II, Karlsruhe Institute of Technology (KIT), Karlsruhe, 76131, Germany
| | - Manfred Focke
- Botanical Institute II, Karlsruhe Institute of Technology (KIT), Karlsruhe, 76131, Germany
| | - Holger Puchta
- Botanical Institute II, Karlsruhe Institute of Technology (KIT), Karlsruhe, 76131, Germany
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33
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Replication-Associated Recombinational Repair: Lessons from Budding Yeast. Genes (Basel) 2016; 7:genes7080048. [PMID: 27548223 PMCID: PMC4999836 DOI: 10.3390/genes7080048] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Revised: 08/05/2016] [Accepted: 08/09/2016] [Indexed: 12/23/2022] Open
Abstract
Recombinational repair processes multiple types of DNA lesions. Though best understood in the repair of DNA breaks, recombinational repair is intimately linked to other situations encountered during replication. As DNA strands are decorated with many types of blocks that impede the replication machinery, a great number of genomic regions cannot be duplicated without the help of recombinational repair. This replication-associated recombinational repair employs both the core recombination proteins used for DNA break repair and the specialized factors that couple replication with repair. Studies from multiple organisms have provided insights into the roles of these specialized factors, with the findings in budding yeast being advanced through use of powerful genetics and methods for detecting DNA replication and repair intermediates. In this review, we summarize recent progress made in this organism, ranging from our understanding of the classical template switch mechanisms to gap filling and replication fork regression pathways. As many of the protein factors and biological principles uncovered in budding yeast are conserved in higher eukaryotes, these findings are crucial for stimulating studies in more complex organisms.
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34
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García-Rodríguez N, Wong RP, Ulrich HD. Functions of Ubiquitin and SUMO in DNA Replication and Replication Stress. Front Genet 2016; 7:87. [PMID: 27242895 PMCID: PMC4865505 DOI: 10.3389/fgene.2016.00087] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 04/27/2016] [Indexed: 12/14/2022] Open
Abstract
Complete and faithful duplication of its entire genetic material is one of the essential prerequisites for a proliferating cell to maintain genome stability. Yet, during replication DNA is particularly vulnerable to insults. On the one hand, lesions in replicating DNA frequently cause a stalling of the replication machinery, as most DNA polymerases cannot cope with defective templates. This situation is aggravated by the fact that strand separation in preparation for DNA synthesis prevents common repair mechanisms relying on strand complementarity, such as base and nucleotide excision repair, from working properly. On the other hand, the replication process itself subjects the DNA to a series of hazardous transformations, ranging from the exposure of single-stranded DNA to topological contortions and the generation of nicks and fragments, which all bear the risk of inducing genomic instability. Dealing with these problems requires rapid and flexible responses, for which posttranslational protein modifications that act independently of protein synthesis are particularly well suited. Hence, it is not surprising that members of the ubiquitin family, particularly ubiquitin itself and SUMO, feature prominently in controlling many of the defensive and restorative measures involved in the protection of DNA during replication. In this review we will discuss the contributions of ubiquitin and SUMO to genome maintenance specifically as they relate to DNA replication. We will consider cases where the modifiers act during regular, i.e., unperturbed stages of replication, such as initiation, fork progression, and termination, but also give an account of their functions in dealing with lesions, replication stalling and fork collapse.
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35
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Xu X, Lin A, Zhou C, Blackwell SR, Zhang Y, Wang Z, Feng Q, Guan R, Hanna MD, Chen Z, Xiao W. Involvement of budding yeast Rad5 in translesion DNA synthesis through physical interaction with Rev1. Nucleic Acids Res 2016; 44:5231-45. [PMID: 27001510 PMCID: PMC4914093 DOI: 10.1093/nar/gkw183] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Accepted: 03/09/2016] [Indexed: 11/17/2022] Open
Abstract
DNA damage tolerance (DDT) is responsible for genomic stability and cell viability by bypassing the replication block. In Saccharomyces cerevisiae DDT employs two parallel branch pathways to bypass the DNA lesion, namely translesion DNA synthesis (TLS) and error-free lesion bypass, which are mediated by sequential modifications of PCNA. Rad5 has been placed in the error-free branch of DDT because it contains an E3 ligase domain required for PCNA polyubiquitination. Rad5 is a multi-functional protein and may also play a role in TLS, since it interacts with the TLS polymerase Rev1. In this study we mapped the Rev1-interaction domain in Rad5 to the amino acid resolution and demonstrated that Rad5 is indeed involved in TLS possibly through recruitment of Rev1. Genetic analyses show that the dual functions of Rad5 can be separated and reconstituted. Crystal structure analysis of the Rad5–Rev1 interaction reveals a consensus RFF motif in the Rad5 N-terminus that binds to a hydrophobic pocket within the C-terminal domain of Rev1 that is highly conserved in eukaryotes. This study indicates that Rad5 plays a critical role in pathway choice between TLS and error-free DDT.
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Affiliation(s)
- Xin Xu
- College of Life Sciences, Capital Normal University, Beijing 100048, China
| | - Aiyang Lin
- College of Life Sciences, Capital Normal University, Beijing 100048, China
| | - Cuiyan Zhou
- Center for Structure Biology, School of Life Science, Tsinghua University, Beijing 100084, China
| | - Susan R Blackwell
- Department of Microbiology and Immunology, University of Saskatchewan, Saskatoon, SK S7N 5E5, Canada
| | - Yiran Zhang
- College of Life Sciences, Capital Normal University, Beijing 100048, China
| | - Zihao Wang
- College of Life Sciences, Capital Normal University, Beijing 100048, China
| | - Qianqian Feng
- College of Life Sciences, Capital Normal University, Beijing 100048, China
| | - Ruifang Guan
- Center for Structure Biology, School of Life Science, Tsinghua University, Beijing 100084, China
| | - Michelle D Hanna
- Department of Microbiology and Immunology, University of Saskatchewan, Saskatoon, SK S7N 5E5, Canada
| | - Zhucheng Chen
- Center for Structure Biology, School of Life Science, Tsinghua University, Beijing 100084, China
| | - Wei Xiao
- College of Life Sciences, Capital Normal University, Beijing 100048, China Department of Microbiology and Immunology, University of Saskatchewan, Saskatoon, SK S7N 5E5, Canada
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36
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Kile AC, Chavez DA, Bacal J, Eldirany S, Korzhnev DM, Bezsonova I, Eichman BF, Cimprich KA. HLTF's Ancient HIRAN Domain Binds 3' DNA Ends to Drive Replication Fork Reversal. Mol Cell 2015; 58:1090-100. [PMID: 26051180 DOI: 10.1016/j.molcel.2015.05.013] [Citation(s) in RCA: 151] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Revised: 04/29/2015] [Accepted: 05/01/2015] [Indexed: 12/20/2022]
Abstract
Stalled replication forks are a critical problem for the cell because they can lead to complex genome rearrangements that underlie cell death and disease. Processes such as DNA damage tolerance and replication fork reversal protect stalled forks from these events. A central mediator of these DNA damage responses in humans is the Rad5-related DNA translocase, HLTF. Here, we present biochemical and structural evidence that the HIRAN domain, an ancient and conserved domain found in HLTF and other DNA processing proteins, is a modified oligonucleotide/oligosaccharide (OB) fold that binds to 3' ssDNA ends. We demonstrate that the HIRAN domain promotes HLTF-dependent fork reversal in vitro through its interaction with 3' ssDNA ends found at forks. Finally, we show that HLTF restrains replication fork progression in cells in a HIRAN-dependent manner. These findings establish a mechanism of HLTF-mediated fork reversal and provide insight into the requirement for distinct fork remodeling activities in the cell.
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Affiliation(s)
- Andrew C Kile
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Diana A Chavez
- Department of Biological Sciences and Center for Structural Biology, Vanderbilt University, Nashville, TN 37232, USA
| | - Julien Bacal
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Sherif Eldirany
- Department of Molecular Biology and Biophysics, University of Connecticut Health Center, Farmington, CT 06032, USA
| | - Dmitry M Korzhnev
- Department of Molecular Biology and Biophysics, University of Connecticut Health Center, Farmington, CT 06032, USA
| | - Irina Bezsonova
- Department of Molecular Biology and Biophysics, University of Connecticut Health Center, Farmington, CT 06032, USA
| | - Brandt F Eichman
- Department of Biological Sciences and Center for Structural Biology, Vanderbilt University, Nashville, TN 37232, USA.
| | - Karlene A Cimprich
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA.
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