DNA mismatch repair protein Msh3; MutS holomolog 3; divergent upstream protein; DUP; mismatch repair protein 1; MRP1 (MSH3, DUC1, DUG)

Function

• component of the post-replicative DNA mismatch repair system (MMR)
• heterodimerizes with MSH2 to form mutS beta which binds to DNA mismatches thereby initiating DNA repair
• when bound, the mutS beta heterodimer bends the DNA helix & shields approximately 20 base pairs
• mutS beta recognizes large insertion-deletion loops (IDL) up to 13 nucleotides long
• after mismatch binding, forms a ternary complex with the mutL alpha heterodimer, which is thought to be responsible for directing the downstream MMR events, including strand discrimination, excision, & resynthesis
• phosphorylated upon DNA damage, probably by ATM or ATR
• heterodimer consisting of MSH2-MSH3 (mutS beta)
• forms a ternary complex with mutL alpha (MLH1-PMS1)
• interacts with EXO1

Structure

• belongs to the DNA mismatch repair mutS family, MSH3 subfamily

Pathology

• defects in MSH3 are a cause of susceptibility to endometrial cancer

More general terms

• mutS family protein
• phosphoprotein

Component of

• MutS-beta

Database

• UniProt: http://www.uniprot.org/uniprot/P20585.html
• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=4437
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:4437
• OMIM: https://mirror.omim.org/entry/600887
• OMIM: https://mirror.omim.org/entry/608089