The Experts below are selected from a list of 1911 Experts worldwide ranked by ideXlab platform
Julian E Sale - One of the best experts on this subject based on the ideXlab platform.
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vertebrate dna damage tolerance requires the c terminus but not BRCT or transferase Domains of rev1
Nucleic Acids Research, 2005Co-Authors: Annalaura Ross, Laura J Simpson, Julian E SaleAbstract:REV1 is central to the DNA damage response of eukaryotes through an as yet poorly understood role in translesion synthesis. REV1 is a member of the Y-type DNA polymerase family and is capable of in vitro deoxycytidyl transferase activity opposite a range of damaged bases. However, non-catalytic roles for REV1 have been suggested by the Saccharomyces cerevisiae rev1-1 mutant, which carries a point mutation in the N-terminal BRCT Domain, and the recently demonstrated ability of the mammalian protein to interact with each of the other translesion polymerases via its extreme C-terminus. Here, we show that a region adjacent to this polymerase interacting Domain mediates an interaction with PCNA. These C-terminal Domains of REV1 are necessary, although not sufficient, for effective tolerance of DNA damage in the avian cell line DT40, while the BRCT Domain and transferase activity are not directly required. Together these data provide strong support for REV1 playing an important non-catalytic role in coordinating translesion synthesis. Further, unlike in budding yeast, rad18 is not epistatic to rev1 for DNA damage tolerance suggesting that REV1 and RAD18 play largely independent roles in the control of vertebrate translesion synthesis.
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vertebrate dna damage tolerance requires the c terminus but not BRCT or transferase Domains of rev1
Nucleic Acids Research, 2005Co-Authors: Annalaura Ross, Laura J Simpson, Julian E SaleAbstract:REV1 is central to the DNA damage response of eukaryotes through an as yet poorly understood role in translesion synthesis. REV1 is a member of the Y-type DNA polymerase family and is capable of in vitro deoxycytidyl transferase activity opposite a range of damaged bases. However, non-catalytic roles for REV1 have been suggested by the Saccharomyces cerevisiae rev1-1 mutant, which carries a point mutation in the N-terminal BRCT Domain, and the recently demonstrated ability of the mammalian protein to interact with each of the other translesion polymerases via its extreme C-terminus. Here, we show that a region adjacent to this polymerase interacting Domain mediates an interaction with PCNA. These C-terminal Domains of REV1 are necessary, although not sufficient, for effective tolerance of DNA damage in the avian cell line DT40, while the BRCT Domain and transferase activity are not directly required. Together these data provide strong support for REV1 playing an important non-catalytic role in coordinating translesion synthesis. Further, unlike in budding yeast, rad18 is not epistatic to rev1 for DNA damage tolerance suggesting that REV1 and RAD18 play largely independent roles in the control of vertebrate translesion synthesis.
Paul Russell - One of the best experts on this subject based on the ideXlab platform.
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multi BRCT Domain protein brc1 links rhp18 rad18 and γh2a to maintain genome stability during s phase
Molecular and Cellular Biology, 2017Co-Authors: Michael C Reubens, Sophie Rozenzhak, Paul RussellAbstract:DNA replication involves the inherent risk of genome instability, since replisomes invariably encounter DNA lesions or other structures that stall or collapse replication forks during the S phase. In the fission yeast Schizosaccharomyces pombe, the multi-BRCT Domain protein Brc1, which is related to budding yeast Rtt107 and mammalian PTIP, plays an important role in maintaining genome integrity and cell viability when cells experience replication stress. The C-terminal pair of BRCT Domains in Brc1 were previously shown to bind phosphohistone H2A (γH2A) formed by Rad3/ATR checkpoint kinase at DNA lesions; however, the putative scaffold interactions involving the N-terminal BRCT Domains 1 to 4 of Brc1 have remained obscure. Here, we show that these Domains bind Rhp18/Rad18, which is an E3 ubiquitin protein ligase that has crucial functions in postreplication repair. A missense allele in BRCT Domain 4 of Brc1 disrupts binding to Rhp18 and causes sensitivity to replication stress. Brc1 binding to Rhp18 and γH2A are required for the Brc1 overexpression suppression of smc6-74, a mutation that impairs the Smc5/6 structural maintenance of chromosomes complex required for chromosome integrity and repair of collapsed replication forks. From these findings, we propose that Brc1 provides scaffolding functions linking γH2A, Rhp18, and Smc5/6 complex at damaged replication forks.
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multi BRCT Domain protein brc1 links rhp18 rad18 and γh2a to maintain genome stability during s phase
bioRxiv, 2017Co-Authors: Michael C Reubens, Sophie Rozenzhak, Paul RussellAbstract:DNA replication involves the inherent risk of genome instability, as replisomes invariably encounter DNA lesions or other structures that stall or collapse replication forks during S-phase. In the fission yeast Schizosaccharomyces pombe, the multi-BRCT Domain protein Brc1, which is related to budding yeast Rtt107 and mammalian PTIP, plays an important role in maintaining genome integrity and cell viability when cells experience replication stress. The C-terminal pair of BRCT Domains in Brc1 were previously shown to bind phospho-histone H2A (γH2A) formed by Rad3/ATR checkpoint kinase at DNA lesions; however, the putative scaffold interactions involving the N-terminal BRCT Domains 1-4 of Brc1 have remained obscure. Here we show that these Domains bind Rhp18/Rad18, which is an E3 ubiquitin protein ligase that has crucial functions in postreplication repair. A missense allele in BRCT Domain 4 of Brc1 disrupts binding to Rhp18 and causes sensitivity to replication stress. Brc1 binding to Rhp18 and γH2A are required for the Brc1-overexpression suppression of smc6-74, which impairs the Smc5/6 structural maintenance of chromosomes complex required for chromosome integrity and repair of collapsed replication forks. From these findings we propose that Brc1 provides scaffolding functions linking γH2A, Rhp18, and Smc5/6 complex at damaged replication forks
Keith W Caldecott - One of the best experts on this subject based on the ideXlab platform.
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efficient single strand break repair requires binding to both poly adp ribose and dna by the central BRCT Domain of xrcc1
Cell Reports, 2019Co-Authors: Luis M Polo, Keith W Caldecott, Peter Hornyak, Fernando Garces, Zhihong Zeng, Richard Hailstone, Steve Matthews, Antony W Oliver, Laurence H PearlAbstract:XRCC1 accelerates repair of DNA single-strand breaks by acting as a scaffold protein for the recruitment of Polβ, LigIIIα, and end-processing factors, such as PNKP and APTX. XRCC1 itself is recruited to DNA damage through interaction of its central BRCT Domain with poly(ADP-ribose) chains generated by PARP1 or PARP2. XRCC1 is believed to interact directly with DNA at sites of damage, but the molecular basis for this interaction within XRCC1 remains unclear. We now show that the central BRCT Domain simultaneously mediates interaction of XRCC1 with poly(ADP-ribose) and DNA, through separate and non-overlapping binding sites on opposite faces of the Domain. Mutation of residues within the DNA binding site, which includes the site of a common disease-associated human polymorphism, affects DNA binding of this XRCC1 Domain in vitro and impairs XRCC1 recruitment and retention at DNA damage and repair of single-strand breaks in vivo. For graphical abstract see published version.
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The BRCT Domain: Signaling with Friends?
Science, 2003Co-Authors: Keith W CaldecottAbstract:The tandem BRCT Domains of the tumor suppressor protein BRCA1 are thought to contribute to this protein9s function in the cellular response to DNA damage. In his Perspective, Caldecott discusses new work ( Yu et al., Manke et al.) showing that the BRCT Domains of BRCA1 and of other proteins bind specifically to phosphorylated amino acids in their protein partners.
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mutation of a BRCT Domain selectively disrupts dna single strand break repair in noncycling chinese hamster ovary cells
Proceedings of the National Academy of Sciences of the United States of America, 2000Co-Authors: David J Moore, Richard M Taylor, Paula M Clements, Keith W CaldecottAbstract:The DNA single-strand break repair protein XRCC1 contains a BRCT Domain that binds and stabilizes intracellular DNA ligase III protein. We recently demonstrated that this Domain is largely dispensable for single-strand break repair and cellular resistance to DNA base damage in cycling cells. Here, we report that the BRCT Domain is required for single-strand break repair in noncycling cells. Mutations that disrupt the BRCT Domain and prevent DNA ligase III interaction abolished XRCC1-dependent repair in serum-starved Chinese hamster ovary cells, and reentry into cell cycle induced by readdition of serum restored repair. Elevating DNA ligase III levels in XRCC1 mutant cells using proteosome inhibitors or by expressing XRCC1 protein in which the BRCT Domain is disrupted but can still bind DNA ligase III failed to restore repair in noncycling cells. The requirement for the BRCT Domain for DNA strand break repair is thus for more than simply binding and stabilizing DNA ligase III. These data provide evidence in support of a selective role for a DNA repair protein or protein Domain in noncycling cells. We propose that the XRCC1 C-terminal BRCT Domain may be important for genetic stability in postmitotic cells in vivo.
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a cell cycle specific requirement for the xrcc1 BRCT ii Domain during mammalian dna strand break repair
Molecular and Cellular Biology, 2000Co-Authors: Richard M Taylor, David J Moore, Jenna Whitehouse, Penny A Johnson, Keith W CaldecottAbstract:XRCC1 protein is essential for viability in mammals and is required for efficient DNA single-strand break repair and genetic stability following DNA base damage. We report here that XRCC1-dependent strand break repair in G1 phase of the cell cycle is abolished by mutations created within the XRCC1 BRCT Domain that interact with DNA ligase III. In contrast, XRCC1-dependent DNA strand break repair in S phase is largely unaffected by these mutations. These data describe a cell cycle-specific role for a BRCT Domain, and we conclude that the XRCC1-DNA ligase III complex is required for DNA strand break repair in G1 phase of the cell cycle but is dispensable for this process in S phase. The S-phase DNA repair process can remove both strand breaks induced in S phase and those that persist from G1 and can in part compensate for lack of repair in G1. This process correlates with the appearance of XRCC1 nuclear foci that colocalize with Rad51 and may thus function in concert with homologous recombination.
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role of a BRCT Domain in the interaction of dna ligase iii α with the dna repair protein xrcc1
Current Biology, 1998Co-Authors: Richard M Taylor, Bill Wickstead, Sam Cronin, Keith W CaldecottAbstract:The BRCT Domain (for BRCA1 carboxyl terminus) is a protein motif of unknown function, comprising approximately 100 amino acids in five conserved blocks denoted A-E. BRCT Domains are present in the tumour suppressor protein BRCA1 [1-3], and the Domain is found in over 40 other proteins, defining a superfamily that includes DNA ligase III-alpha and the essential human DNA repair protein XRCC1. DNA ligase III-alpha and XRCC1 interact via their carboxyl termini, close to or within regions that contain a BRCT Domain [4]. To examine whether the primary role of the carboxy-terminal BRCT Domain of XRCC1 (denoted BRCT II) is to mediate the interaction with DNA ligase III-alpha, we identified the regions of the Domain that are required and sufficient for the interaction. An XRCC1 protein in which the conserved D-block tryptophan was disrupted by point mutation retained the ability to interact with DNA ligase III-alpha, so this tryptophan must mediate a different, although conserved, role. XRCC1 in which the weakly conserved C-block was mutated lost the ability to interact with DNA ligase III-alpha. Moreover, 20 amino acids spanning the C-block of BRCT II conferred full DNA ligase III-alpha binding activity upon an unrelated polypeptide. An XRCC1 protein in which this 20mer was deleted could not maintain normal levels of DNA ligase III-alpha in transfected rodent cells, a phenotype associated with defective repair [5]. In summary, these data demonstrate that a BRCT Domain can mediate a biologically important protein-protein interaction, and support the existence of additional roles.
Annalaura Ross - One of the best experts on this subject based on the ideXlab platform.
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vertebrate dna damage tolerance requires the c terminus but not BRCT or transferase Domains of rev1
Nucleic Acids Research, 2005Co-Authors: Annalaura Ross, Laura J Simpson, Julian E SaleAbstract:REV1 is central to the DNA damage response of eukaryotes through an as yet poorly understood role in translesion synthesis. REV1 is a member of the Y-type DNA polymerase family and is capable of in vitro deoxycytidyl transferase activity opposite a range of damaged bases. However, non-catalytic roles for REV1 have been suggested by the Saccharomyces cerevisiae rev1-1 mutant, which carries a point mutation in the N-terminal BRCT Domain, and the recently demonstrated ability of the mammalian protein to interact with each of the other translesion polymerases via its extreme C-terminus. Here, we show that a region adjacent to this polymerase interacting Domain mediates an interaction with PCNA. These C-terminal Domains of REV1 are necessary, although not sufficient, for effective tolerance of DNA damage in the avian cell line DT40, while the BRCT Domain and transferase activity are not directly required. Together these data provide strong support for REV1 playing an important non-catalytic role in coordinating translesion synthesis. Further, unlike in budding yeast, rad18 is not epistatic to rev1 for DNA damage tolerance suggesting that REV1 and RAD18 play largely independent roles in the control of vertebrate translesion synthesis.
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vertebrate dna damage tolerance requires the c terminus but not BRCT or transferase Domains of rev1
Nucleic Acids Research, 2005Co-Authors: Annalaura Ross, Laura J Simpson, Julian E SaleAbstract:REV1 is central to the DNA damage response of eukaryotes through an as yet poorly understood role in translesion synthesis. REV1 is a member of the Y-type DNA polymerase family and is capable of in vitro deoxycytidyl transferase activity opposite a range of damaged bases. However, non-catalytic roles for REV1 have been suggested by the Saccharomyces cerevisiae rev1-1 mutant, which carries a point mutation in the N-terminal BRCT Domain, and the recently demonstrated ability of the mammalian protein to interact with each of the other translesion polymerases via its extreme C-terminus. Here, we show that a region adjacent to this polymerase interacting Domain mediates an interaction with PCNA. These C-terminal Domains of REV1 are necessary, although not sufficient, for effective tolerance of DNA damage in the avian cell line DT40, while the BRCT Domain and transferase activity are not directly required. Together these data provide strong support for REV1 playing an important non-catalytic role in coordinating translesion synthesis. Further, unlike in budding yeast, rad18 is not epistatic to rev1 for DNA damage tolerance suggesting that REV1 and RAD18 play largely independent roles in the control of vertebrate translesion synthesis.
Junjie Chen - One of the best experts on this subject based on the ideXlab platform.
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a pocket on the surface of the n terminal BRCT Domain of mcph1 is required to prevent abnormal chromosome condensation
Journal of Molecular Biology, 2010Co-Authors: Mark W Richards, Justin W C Leung, Mark S Roe, Junjie Chen, Richard BaylissAbstract:Mcph1 is mutated in autosomal recessive primary microcephaly and premature chromosome condensation (PCC) syndrome. Increased chromosome condensation is a common feature of cells isolated from patients afflicted with either disease. Normal cells depleted of Mcph1 also exhibit PCC phenotype. Human Mcph1 contains three BRCA1-carboxyl terminal (BRCT) Domains, the first of which (Mcph1N) is necessary for the prevention of PCC. The only known disease-associated missense mutation in Mcph1 resides in this Domain (T27R). We have determined the X-ray crystal structure of human Mcph1N to 1.6 A resolution. Compared with other BRCT Domain structures, the most striking differences are an elongated, ordered β1–α1 loop and an adjacent hydrophobic pocket. This pocket is in the equivalent structural position to the phosphate binding site of BRCT Domains that recognize phospho-proteins, although the phosphate-binding residues are absent in Mcph1N. Mutations in the pocket abrogate the ability of full-length Mcph1 to rescue the PCC phenotype of Mcph1−/− mouse embryonic fibroblast cells, suggesting that it forms an essential part of a protein–protein interaction site necessary to prevent PCC.
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structure of a second BRCT Domain identified in the nijmegen breakage syndrome protein nbs1 and its function in an mdc1 dependent localization of nbs1 to dna damage sites
Journal of Molecular Biology, 2008Co-Authors: Gaofeng Cui, Junjie Chen, Maria Victoria Botuyan, Georges MerAbstract:Abstract The Nijmegen breakage syndrome protein Nbs1 is a component of the MRN (Mre11–Rad50–Nbs1) complex, central to the DNA damage response. While Nbs1 is generally believed to encompass a forkhead-associated Domain linked to a breast cancer C-terminal (BRCT) Domain, to date there is no experimental information on its three-dimensional structure. Through nuclear magnetic resonance (NMR) three-dimensional structure determination, we demonstrate that there is a second BRCT Domain (BRCT2) in Nbs1. The Domain has the characteristic BRCT topology, but with a long insertion shown to be flexible by NMR relaxation measurements. In the absence of sequence similarity to other proteins, a search for structural analogs of BRCT2 returned the second BRCT Domain of the tandem BRCT repeats of cell cycle checkpoint proteins MDC1 (mediator of DNA damage checkpoint protein 1) and BRCA1 (breast cancer protein 1), suggesting that like MDC1 and BRCA1, Nbs1 also possesses tandem BRCT Domains with phosphoprotein binding ability. Structure-based single point mutations in human Nbs1 were evaluated in vivo and revealed that BRCT2 is essential for an MDC1-dependent relocalization of Nbs1 to DNA damage sites, most likely through a direct interaction of Nbs1 tandem BRCT Domains with phosphorylated MDC1.
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the tandem BRCT Domain of 53bp1 is not required for its repair function
Journal of Biological Chemistry, 2006Co-Authors: Irene M Ward, Georges Mer, Claudia C S Chini, Ja Eun Kim, Kay Minn, Junjie ChenAbstract:53BP1 plays an important role in cellular response to DNA damage. It is thought to be the mammalian homologue of budding yeast Rad9 and/or fission yeast Crb2. Rad9/Crb2 are bona fide checkpoint proteins whose activation requires their corresponding C-terminal tandem BRCT (BRCA1 C-terminal) motifs, which mediate their oligomerization and phosphorylation at multiple sites following DNA damage. Here we show that the function of human 53BP1 similarly depends on its oligomerization and phosphorylation at multiple sites but in a BRCT Domain-independent manner. Moreover, unlike its proposed yeast counterparts, human 53BP1 only has limited checkpoint functions but rather acts as an adaptor in the repair of DNA double strand breaks. This difference in function may reflect the higher complexity of the DNA damage response network in metazoa including the evolution of other BRCT Domain-containing proteins that may have functions redundant or overlapping with those of 53BP1.
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the BRCT Domain is a phospho protein binding Domain
Science, 2003Co-Authors: Claudia C S Chini, Georges Mer, Junjie ChenAbstract:The carboxyl-terminal Domain (BRCT) of the Breast Cancer Gene 1 (BRCA1) protein is an evolutionarily conserved module that exists in a large number of proteins from prokaryotes to eukaryotes. Although most BRCT Domain–containing proteins participate in DNA-damage checkpoint or DNA-repair pathways, or both, the function of the BRCT Domain is not fully understood. We show that the BRCA1 BRCT Domain directly interacts with phosphorylated BRCA1-Associated Carboxyl-terminal Helicase (BACH1). This specific interaction between BRCA1 and phosphorylated BACH1 is cell cycle regulated and is required for DNA damage–induced checkpoint control during the transition from G2 to M phase of the cell cycle. Further, we show that two other BRCT Domains interact with their respective physiological partners in a phosphorylation-dependent manner. Thirteen additional BRCT Domains also preferentially bind phospho-peptides rather than nonphosphorylated control peptides. These data imply that the BRCT Domain is a phospho-protein binding Domain involved in cell cycle control.