title: Exonuclease 1-dependent and independent mismatch repair.
abstract: DNA mismatch repair (MMR) acts to repair mispaired bases resulting from misincorporation errors during DNA replication and also recognizes mispaired bases in recombination (HR) intermediates. Exonuclease 1 (Exo1) is a 5' → 3' exonuclease that participates in a number of DNA repair pathways. Exo1 was identified as an exonuclease that participates in Saccharomyces cerevisiae and human MMR where it functions to excise the daughter strand after mispair recognition, and additionally Exo1 functions in end resection during HR. However, Exo1 is not absolutely required for end resection during HR in vivo. Similarly, while Exo1 is required in MMR reactions that have been reconstituted in vitro, genetics studies have shown that it is not absolutely required for MMR in vivo suggesting the existence of Exo1-independent and Exo1-dependent MMR subpathways. Here, we review what is known about the Exo1-independent and Exo1-dependent subpathways, including studies of mutations in MMR genes that specifically disrupt either subpathway.
authors.affiliation: Ludwig Institute for Cancer Research, 9500 Gilman Drive, La Jolla, CA 92093-0669, USA.
authors.forename: Eva M
authors.initials: EM
authors.lastname: Goellner
authors.affiliation: Ludwig Institute for Cancer Research, 9500 Gilman Drive, La Jolla, CA 92093-0669, USA; Departments of Medicine, University of California, San Diego School of Medicine, 9500 Gilman Drive, La Jolla, CA 92093-0669, USA.
authors.forename: Christopher D
authors.initials: CD
authors.lastname: Putnam
authors.affiliation: Ludwig Institute for Cancer Research, 9500 Gilman Drive, La Jolla, CA 92093-0669, USA; Departments of Cellular and Molecular Medicine, University of California, San Diego School of Medicine, 9500 Gilman Drive, La Jolla, CA 92093-0669, USA; Moores - UCSD Cancer Center, University of California, San Diego School of Medicine, 9500 Gilman Drive, La Jolla, CA 92093-0669, USA; Institute of Genomic Medicine, University of California, San Diego School of Medicine, 9500 Gilman Drive, La Jolla, CA 92093-0669, USA. Electronic address: rkolodner@ucsd.edu.
authors.forename: Richard D
authors.initials: RD
authors.lastname: Kolodner
mesh_terms: D020137:Base Pair Mismatch; D053903:DNA Breaks, Double-Stranded; D053843:DNA Mismatch Repair; D004261:DNA Replication; D004271:DNA, Fungal / Q000737:chemistry* / Q000378:metabolism; D005090:Exodeoxyribonucleases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D015966:Gene Expression Regulation, Fungal; D006801:Humans; D008958:Models, Molecular; D009154:Mutation; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D012441:Saccharomyces cerevisiae / Q000201:enzymology* / Q000235:genetics
chemical_list: D004271:DNA, Fungal; D005090:Exodeoxyribonucleases; C028450:exodeoxyribonuclease I
keywords: DNA replication fidelity; Excision; Mispaired base; Mlh1–Pms1; Msh2–Msh6; Mutagenesis; Recombination