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Furman CM, Elbashir R, Pannafino G, Clark NL, Alani E. Experimental exchange of paralogous domains in the MLH family provides evidence of sub-functionalization after gene duplication. G3 (BETHESDA, MD.) 2021; 11:jkab111. [PMID: 33871573 PMCID: PMC8495741 DOI: 10.1093/g3journal/jkab111] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 03/31/2021] [Indexed: 01/24/2023]
Abstract
Baker's yeast contains a large number of duplicated genes; some function redundantly, whereas others have more specialized roles. We used the MLH family of DNA mismatch repair (MMR) proteins as a model to better understand the steps that lead to gene specialization following a gene duplication event. We focused on two highly conserved yeast MLH proteins, Pms1 and Mlh3, with Pms1 having a major role in the repair of misincorporation events during DNA replication and Mlh3 acting to resolve recombination intermediates in meiosis to form crossovers. The baker's yeast Mlh3 and Pms1 proteins are significantly diverged (19% overall identity), suggesting that an extensive number of evolutionary steps, some major, others involving subtle refinements, took place to diversify the MLH proteins. Using phylogenetic and molecular approaches, we provide evidence that all three domains (N-terminal ATP binding, linker, C-terminal endonuclease/MLH interaction) in the MLH protein family are critical for conferring pathway specificity. Importantly, mlh3 alleles in the ATP binding and endonuclease domains improved MMR functions in strains lacking the Pms1 protein and did not disrupt Mlh3 meiotic functions. This ability for mlh3 alleles to complement the loss of Pms1 suggests that an ancestral Pms1/Mlh3 protein was capable of performing both MMR and crossover functions. Our strategy for analyzing MLH pathway specificity provides an approach to understand how paralogs have evolved to support distinct cellular processes.
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Affiliation(s)
- Christopher M Furman
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853-2703, USA
| | - Ryan Elbashir
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853-2703, USA
| | - Gianno Pannafino
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853-2703, USA
| | - Nathan L Clark
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84132, USA
| | - Eric Alani
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853-2703, USA
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2
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Kobaisi F, Fayyad N, Sulpice E, Badran B, Fayyad-Kazan H, Rachidi W, Gidrol X. High-throughput synthetic rescue for exhaustive characterization of suppressor mutations in human genes. Cell Mol Life Sci 2020; 77:4209-4222. [PMID: 32270227 PMCID: PMC7588364 DOI: 10.1007/s00018-020-03519-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 03/21/2020] [Accepted: 03/30/2020] [Indexed: 02/06/2023]
Abstract
Inherited or acquired mutations can lead to pathological outcomes. However, in a process defined as synthetic rescue, phenotypic outcome created by primary mutation is alleviated by suppressor mutations. An exhaustive characterization of these mutations in humans is extremely valuable to better comprehend why patients carrying the same detrimental mutation exhibit different pathological outcomes or different responses to treatment. Here, we first review all known suppressor mutations' mechanisms characterized by genetic screens on model species like yeast or flies. However, human suppressor mutations are scarce, despite some being discovered based on orthologue genes. Because of recent advances in high-throughput screening, developing an inventory of human suppressor mutations for pathological processes seems achievable. In addition, we review several screening methods for suppressor mutations in cultured human cells through knock-out, knock-down or random mutagenesis screens on large scale. We provide examples of studies published over the past years that opened new therapeutic avenues, particularly in oncology.
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Affiliation(s)
- Farah Kobaisi
- University of Grenoble Alpes, CEA, INSERM, IRIG-BGE U1038, 38000, Grenoble, France
- Laboratory of Cancer Biology and Molecular Immunology, Faculty of Sciences I, Lebanese University, Hadath, Lebanon
- University of Grenoble Alpes, SYMMES/CIBEST UMR 5819 UGA-CNRS-CEA, IRIG/CEA-Grenoble, Grenoble, France
| | - Nour Fayyad
- University of Grenoble Alpes, SYMMES/CIBEST UMR 5819 UGA-CNRS-CEA, IRIG/CEA-Grenoble, Grenoble, France
| | - Eric Sulpice
- University of Grenoble Alpes, CEA, INSERM, IRIG-BGE U1038, 38000, Grenoble, France
| | - Bassam Badran
- Laboratory of Cancer Biology and Molecular Immunology, Faculty of Sciences I, Lebanese University, Hadath, Lebanon
| | - Hussein Fayyad-Kazan
- Laboratory of Cancer Biology and Molecular Immunology, Faculty of Sciences I, Lebanese University, Hadath, Lebanon
| | - Walid Rachidi
- University of Grenoble Alpes, SYMMES/CIBEST UMR 5819 UGA-CNRS-CEA, IRIG/CEA-Grenoble, Grenoble, France
| | - Xavier Gidrol
- University of Grenoble Alpes, CEA, INSERM, IRIG-BGE U1038, 38000, Grenoble, France.
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3
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Furman CM, Elbashir R, Alani E. Expanded roles for the MutL family of DNA mismatch repair proteins. Yeast 2020; 38:39-53. [PMID: 32652606 DOI: 10.1002/yea.3512] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 07/01/2020] [Accepted: 07/08/2020] [Indexed: 12/31/2022] Open
Abstract
The MutL family of DNA mismatch repair proteins plays a critical role in excising and repairing misincorporation errors during DNA replication. In many eukaryotes, members of this family have evolved to modulate and resolve recombination intermediates into crossovers during meiosis. In these organisms, such functions promote the accurate segregation of chromosomes during the meiosis I division. What alterations occurred in MutL homolog (MLH) family members that enabled them to acquire these new roles? In this review, we present evidence that the yeast Mlh1-Mlh3 and Mlh1-Mlh2 complexes have evolved novel enzymatic and nonenzymatic activities and protein-protein interactions that are critical for their meiotic functions. Curiously, even with these changes, these complexes retain backup and accessory roles in DNA mismatch repair during vegetative growth.
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Affiliation(s)
- Christopher M Furman
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
| | - Ryan Elbashir
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
| | - Eric Alani
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
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4
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Absence of MutSβ leads to the formation of slipped-DNA for CTG/CAG contractions at primate replication forks. DNA Repair (Amst) 2016; 42:107-18. [PMID: 27155933 DOI: 10.1016/j.dnarep.2016.04.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 03/22/2016] [Accepted: 04/05/2016] [Indexed: 11/22/2022]
Abstract
Typically disease-causing CAG/CTG repeats expand, but rare affected families can display high levels of contraction of the expanded repeat amongst offspring. Understanding instability is important since arresting expansions or enhancing contractions could be clinically beneficial. The MutSβ mismatch repair complex is required for CAG/CTG expansions in mice and patients. Oddly, by unknown mechanisms MutSβ-deficient mice incur contractions instead of expansions. Replication using CTG or CAG as the lagging strand template is known to cause contractions or expansions respectively; however, the interplay between replication and repair leading to this instability remains unclear. Towards understanding how repeat contractions may arise, we performed in vitro SV40-mediated replication of repeat-containing plasmids in the presence or absence of mismatch repair. Specifically, we separated repair from replication: Replication mediated by MutSβ- and MutSα-deficient human cells or cell extracts produced slipped-DNA heteroduplexes in the contraction- but not expansion-biased replication direction. Replication in the presence of MutSβ disfavoured the retention of replication products harbouring slipped-DNA heteroduplexes. Post-replication repair of slipped-DNAs by MutSβ-proficient extracts eliminated slipped-DNAs. Thus, a MutSβ-deficiency likely enhances repeat contractions because MutSβ protects against contractions by repairing template strand slip-outs. Replication deficient in LigaseI or PCNA-interaction mutant LigaseI revealed slipped-DNA formation at lagging strands. Our results reveal that distinct mechanisms lead to expansions or contractions and support inhibition of MutSβ as a therapeutic strategy to enhance the contraction of expanded repeats.
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Romanova NV, Crouse GF. Different roles of eukaryotic MutS and MutL complexes in repair of small insertion and deletion loops in yeast. PLoS Genet 2013; 9:e1003920. [PMID: 24204320 PMCID: PMC3814323 DOI: 10.1371/journal.pgen.1003920] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2013] [Accepted: 09/11/2013] [Indexed: 11/18/2022] Open
Abstract
DNA mismatch repair greatly increases genome fidelity by recognizing and removing replication errors. In order to understand how this fidelity is maintained, it is important to uncover the relative specificities of the different components of mismatch repair. There are two major mispair recognition complexes in eukaryotes that are homologues of bacterial MutS proteins, MutSα and MutSβ, with MutSα recognizing base-base mismatches and small loop mispairs and MutSβ recognizing larger loop mispairs. Upon recognition of a mispair, the MutS complexes then interact with homologues of the bacterial MutL protein. Loops formed on the primer strand during replication lead to insertion mutations, whereas loops on the template strand lead to deletions. We show here in yeast, using oligonucleotide transformation, that MutSα has a strong bias toward repair of insertion loops, while MutSβ has an even stronger bias toward repair of deletion loops. Our results suggest that this bias in repair is due to the different interactions of the MutS complexes with the MutL complexes. Two mutants of MutLα, pms1-G882E and pms1-H888R, repair deletion mispairs but not insertion mispairs. Moreover, we find that a different MutL complex, MutLγ, is extremely important, but not sufficient, for deletion repair in the presence of either MutLα mutation. MutSβ is present in many eukaryotic organisms, but not in prokaryotes. We suggest that the biased repair of deletion mispairs may reflect a critical eukaryotic function of MutSβ in mismatch repair.
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Affiliation(s)
- Nina V. Romanova
- Department of Biology, Emory University, Atlanta, Georgia, United States of America
| | - Gray F. Crouse
- Department of Biology, Emory University, Atlanta, Georgia, United States of America
- Winship Cancer Institute, Emory University, Atlanta, Georgia, United States of America
- * E-mail:
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6
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Wang Y, Zhou X, Song Y, Ji X, Zhang A, Zhang G, Gao Z. The mismatch repair gene hPMS1 (human postmeiotic segregation1) is down regulated in oral squamous cell carcinoma. Gene 2013; 524:28-34. [DOI: 10.1016/j.gene.2013.04.030] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2012] [Revised: 03/29/2013] [Accepted: 04/01/2013] [Indexed: 11/27/2022]
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Abstract
The DNA mismatch repair (MMR) system is a major DNA repair pathway whose function is critical for the correction of DNA biosynthetic errors. MMR is initiated by the binding of MutS proteins to mismatches and unpaired nucleotides followed by the recruitment of MutL proteins. The major MutL activity in eukaryotes is performed by MutLα, the heterocomplex of MLH1-PMS1 in yeast and plants and MLH1-PMS2 in humans. We here report the effect the expression of Arabidopsis PMS1 protein exerts on Saccharomyces cerevisiae genomic stability. A strain carrying specific microsatellite instability reporter systems was chosen for the study. The plant protein failed to complement the hypermutator phenotype of a pms1 deficient strain but increased approximately 14-fold and 2,000-fold the mutation rates of his7-2 and lys2::InsE-A 14 loci of MMR proficient strains when compared to wild-type strains, respectively. Overexpressing AtMLH1 in the AtPMS1-overproducing strain generated an increase in mutation rate comparable to that of AtPMS1 expression alone. Deletion of the C-terminal residues implicated in protein-protein interaction and including the putative endonuclease sequence of AtPMS1 completely eliminated the mutator phenotype. Taken together, these results indicate that the plant proteins affect yeast genomic stability, very possibly altering protein-protein interactions that are necessary to complete repair.
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8
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Kremer SA, Erdeniz N, Peterson-Nedry W, Swanson EA, Wehrli M. In vivo analysis in Drosophila reveals differential requirements of contact residues in Axin for interactions with GSK3beta or beta-catenin. Dev Biol 2009; 337:110-23. [PMID: 19850033 DOI: 10.1016/j.ydbio.2009.10.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2009] [Revised: 09/21/2009] [Accepted: 10/13/2009] [Indexed: 01/05/2023]
Abstract
Proper regulation of the Wingless/Wnt signaling pathway is essential for normal development. The scaffolding protein Axin plays a key role in this process through interactions with Drosophila Shaggy and Armadillo. In the current studies, we used a yeast two-hybrid assay to identify ten amino acids in Axin that are critical for in vitro interaction with Shaggy and two for interaction with Armadillo. We then generated five Axin variants in which individual putative contact amino acids were mutated and compared their activity, as assayed by rescue of axin null mutant flies, to that of Axin lacking the entire Shaggy (AxinDeltaSgg) or Armadillo (AxinDeltaArm) binding domain. Although we expected these mutants to function identically to Axin in which the entire binding domain was deleted, we instead observed a spectrum of phenotypic rescue. Specifically, two point mutants within the Shaggy binding domain showed loss of activity similar to that of AxinDeltaSgg and dominantly interfered with complex function, whereas a third mutant allele, AxinK446E, retained most function. Two Axin point mutants within the Armadillo binding domain were weak alleles and retained most function. These findings demonstrate the importance of in vivo verification of the role of specific amino acids within a protein.
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Affiliation(s)
- Susan A Kremer
- Department of Cell and Developmental Biology, Oregon Health and Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA
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Spampinato CP, Gomez RL, Galles C, Lario LD. From bacteria to plants: a compendium of mismatch repair assays. Mutat Res 2009; 682:110-28. [PMID: 19622396 DOI: 10.1016/j.mrrev.2009.07.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2009] [Revised: 06/16/2009] [Accepted: 07/13/2009] [Indexed: 10/20/2022]
Abstract
Mismatch repair (MMR) system maintains genome integrity by correcting mispaired or unpaired bases which have escaped the proofreading activity of DNA polymerases. The basic features of the pathway have been highly conserved throughout evolution, although the nature and number of the proteins involved in the mechanism vary from prokaryotes to eukaryotes and even between humans and plants. Cells deficient in MMR genes have been observed to display a mutator phenotype characterized by an increased rate in spontaneous mutation, instability of microsatellite sequences and illegitimate recombination between diverged DNA sequences. Studies of the mutator phenotype have demonstrated a critical role for the MMR system in mutation avoidance and genetic stability. Here, we briefly review our current knowledge of the MMR mechanism and then focus on the in vivo biochemical and genetic assays used to investigate the function of the MMR proteins in processing DNA mismatches generated during replication and mitotic recombination in Escherichia coli, Saccharomyces cerevisiae, Homo sapiens and Arabidopsis thaliana. An overview of the biochemical assays developed to study mismatch correction in vitro is also provided.
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Affiliation(s)
- Claudia P Spampinato
- Centro de Estudios Fotosintéticos y Bioquímicos, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Argentina.
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10
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Shah SN, Eckert KA. Human postmeiotic segregation 2 exhibits biased repair at tetranucleotide microsatellite sequences. Cancer Res 2009; 69:1143-9. [PMID: 19155293 DOI: 10.1158/0008-5472.can-08-3499] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The mismatch repair (MMR) system plays a major role in removing DNA polymerization errors, and loss of this pathway results in hereditary cancers characterized by microsatellite instability. We investigated microsatellite stability during DNA replication within human postmeiotic segregation 2 (hPMS2)-deficient and proficient human lymphoblastoid cell lines. Using a shuttle vector assay, we measured mutation rates at reporter cassettes containing defined mononucleotide, dinucleotide, and tetranucleotide microsatellite sequences. A mutator phenotype was observed in the hPMS2-deficient cell line. The mutation rate of vectors containing [G/C](10) or [GT/CA](10) alleles was elevated 20-fold to 40-fold in hPMS2-deficient cells, relative to an hPMS2-expressing cell line. We observed a 6-fold and 12-fold relative increase in mutation rate of [TTTC/AAAG](9) and [TTCC/AAGG](9) sequences, respectively, in hPMS2-deficient cells. Mutational specificity analyses suggested that repair by hPMS2 is biased. In the absence of hPMS2, a greater number of microsatellite expansion versus deletion mutations was observed, and expansion rates of the tetranucleotide alleles were similar. In the presence of hPMS2, we observed a 29-fold decrease in the [TTCC/AAGG](9) expansion rate but only a 6-fold decrease for the [TTTC/AAAG](9) allele. Our data indicate that hPMS2 is more protective of tetranucleotide expansions than deletions and that hPMS2 displays a sequence bias, wherein [TTCC/AAGG] sequences are stabilized to a greater extent than [TTTC/AAAG]. Our results allow for greater accuracy during identification of MMR defects by providing a mutational signature characteristic of hPMS2 defect. This study also provides clues to possible mechanisms of repair by hPMS2 in the context of the MMR system.
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Affiliation(s)
- Sandeep N Shah
- Department of Pathology, Gittlen Cancer Research Foundation and Intercollege Graduate Degree Program in Genetics, Pennsylvania State University College of Medicine, Hershey, Pennsylvania 17033, USA
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Erdeniz N, Nguyen M, Deschênes SM, Liskay RM. Mutations affecting a putative MutLalpha endonuclease motif impact multiple mismatch repair functions. DNA Repair (Amst) 2007; 6:1463-70. [PMID: 17567544 PMCID: PMC2366940 DOI: 10.1016/j.dnarep.2007.04.013] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2007] [Accepted: 04/16/2007] [Indexed: 12/11/2022]
Abstract
Mutations in DNA mismatch repair (MMR) lead to increased mutation rates and higher recombination between similar, but not identical sequences, as well as resistance to certain DNA methylating agents. Recently, a component of human MMR machinery, MutLalpha, has been shown to display a latent endonuclease activity. The endonuclease active site appears to include a conserved motif, DQHA(X)(2)E(X)(4)E, within the COOH-terminus of human PMS2. Substitution of the glutamic acid residue (E705) abolished the endonuclease activity and mismatch-dependent excision in vitro. Previously, we showed that the PMS2-E705K mutation and the corresponding mutation in Saccharomyces cerevisiae were both recessive loss of function alleles for mutation avoidance in vivo. Here, we show that mutations impacting this endonuclease motif also significantly affect MMR-dependent suppression of homeologous recombination in yeast and responses to S(n)1-type methylating agents in both yeast and mammalian cells. Thus, our in vivo results suggest that the endonuclease activity of MutLalpha is important not only in MMR-dependent mutation avoidance but also for recombination and damage response functions.
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Affiliation(s)
- Naz Erdeniz
- Department of Molecular and Medical Genetics, Oregon Health & Science University L103, 3181 SW, Sam Jackson Park Road, Portland, OR 97239-3098, United States
| | - Megan Nguyen
- Department of Molecular and Medical Genetics, Oregon Health & Science University L103, 3181 SW, Sam Jackson Park Road, Portland, OR 97239-3098, United States
| | - Suzanne M. Deschênes
- Department of Biology, Sacred Heart University, 5151 Park Ave., Fairfield, CT 06825, United States
| | - R. Michael Liskay
- Department of Molecular and Medical Genetics, Oregon Health & Science University L103, 3181 SW, Sam Jackson Park Road, Portland, OR 97239-3098, United States
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12
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Deschênes SM, Tomer G, Nguyen M, Erdeniz N, Juba NC, Sepúlveda N, Pisani JE, Liskay RM. The E705K mutation in hPMS2 exerts recessive, not dominant, effects on mismatch repair. Cancer Lett 2006; 249:148-56. [PMID: 17029773 PMCID: PMC2366906 DOI: 10.1016/j.canlet.2006.08.008] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2006] [Revised: 08/04/2006] [Accepted: 08/08/2006] [Indexed: 11/21/2022]
Abstract
The hPMS2 mutation E705K is associated with Turcot syndrome. To elucidate the pathogenesis of hPMS2-E705K, we modeled this mutation in yeast and characterized its expression and effects on mutation avoidance in mammalian cells. We found that while hPMS2-E705K (pms1-E738K in yeast) did not significantly affect hPMS2 (Pms1p in yeast) stability or interaction with MLH1, it could not complement the mutator phenotype in MMR-deficient mouse or yeast cells. Furthermore, hPMS2-E705K/pms1-E738K inhibited MMR in wild-type (WT) mammalian cell extracts or yeast cells only when present in excess amounts relative to WT PMS2. Our results strongly suggest that hPMS2-E705K is a recessive loss-of-function allele.
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Affiliation(s)
- Suzanne M Deschênes
- Department of Biology, Sacred Heart University, 5151 Park Ave., Fairfield, CT 06825, USA.
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13
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Plotz G, Zeuzem S, Raedle J. DNA mismatch repair and Lynch syndrome. J Mol Histol 2006; 37:271-83. [PMID: 16821093 DOI: 10.1007/s10735-006-9038-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2006] [Accepted: 06/06/2006] [Indexed: 01/31/2023]
Abstract
The evolutionary conserved mismatch repair proteins correct a wide range of DNA replication errors. Their importance as guardians of genetic integrity is reflected by the tremendous decrease of replication fidelity (two to three orders of magnitude) conferred by their loss. Germline mutations in mismatch repair genes, predominantly MSH2 and MLH1, have been found to underlie the Lynch syndrome (also called hereditary non-polyposis colorectal cancer, HNPCC), a hereditary predisposition for cancer. Lynch syndrome affects predominantly the colon and accounts for 2-5% of all colon cancer cases. During more than 30 years of biochemical, crystallographic and clinical research, deep insight has been achieved in the function of mismatch repair and the diseases that are associated with its loss. We review the biochemistry of mismatch repair and also introduce the clinical, diagnostic and genetic aspects of Lynch syndrome.
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Affiliation(s)
- Guido Plotz
- Klinik für Innere Medizin II, Universitätsklinikum des Saarlandes, Kirrberger Strasse, Gebäude 41, D-66421 Homburg, Germany.
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Abdulovic A, Kim N, Jinks-Robertson S. Mutagenesis and the three R's in yeast. DNA Repair (Amst) 2006; 5:409-21. [PMID: 16412705 DOI: 10.1016/j.dnarep.2005.11.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2005] [Revised: 11/17/2005] [Accepted: 11/17/2005] [Indexed: 11/19/2022]
Abstract
Mutagenesis is a prerequisite for evolution and also is an important contributor to human diseases. Most mutations in actively dividing cells originate during DNA replication as errors introduced when copying an undamaged DNA template or during the bypass of DNA lesions. In addition, mutations can be introduced during the repair of DNA double-strand breaks by either homologous recombination or non-homologous end-joining pathways. Finally, although generally considered to be a very high-fidelity process, the excision repair of DNA damage may be an important contributor to mutagenesis in non-dividing cells. In this review, we will discuss the well-known contributions of DNA replication to mutagenesis in Saccharomyces cerevisiae, as well as the less-appreciated contributions of recombination and repair to mutagenesis in this organism.
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Affiliation(s)
- Amy Abdulovic
- Biochemistry, Cell and Developmental Biology Program of the Graduate Division of Biological and Biomedical Sciences, Emory University, Atlanta, GA 30322, USA
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