Kumar C, et al. (2011) Multiple factors insulate Msh2-Msh6 mismatch repair activity from defects in Msh2 domain I. J Mol Biol 411(4):765-80
Abstract: DNA mismatch repair (MMR) is a highly conserved mutation avoidance mechanism that corrects DNA polymerase misincorporation errors. In initial steps in MMR, Msh2-Msh6 binds mispairs and small insertion/deletion loops, and Msh2-Msh3 binds larger insertion/deletion loops. The msh2Delta1 mutation, which deletes the conserved DNA-binding domain I of Msh2, does not dramatically affect Msh2-Msh6-dependent repair. In contrast, msh2Delta1 mutants show strong defects in Msh2-Msh3 functions. Interestingly, several mutations identified in patients with hereditary non-polyposis colorectal cancer map to domain I of Msh2; none have been found in MSH3. To understand the role of Msh2 domain I in MMR, we examined the consequences of combining the msh2Delta1 mutation with mutations in two distinct regions of MSH6 and those that increase cellular mutational load (pol3-01 and rad27). These experiments reveal msh2Delta1-specific phenotypes in Msh2-Msh6 repair, with significant effects on mutation rates. In vitro assays demonstrate that msh2Delta1-Msh6 DNA binding is less specific for DNA mismatches and produces an altered footprint on a mismatch DNA substrate. Together, these results provide evidence that, in vivo, multiple factors insulate MMR from defects in domain I of Msh2 and provide insights into how mutations in Msh2 domain I may cause hereditary non-polyposis colorectal cancer.CI - Copyright (c) 2011 Elsevier Ltd. All rights reserved.
|Status: Published||Type: Journal Article | Research Support, N.I.H., Extramural||PubMed ID: 21726567|
Topics addressed in this paper
Number of different genes curated to this paper: 5
- To go to the Locus page for a gene, click on the gene name.
|Disease Gene Related|
|Non-Fungal Related Genes/Proteins|
|Protein Physical Properties|
|Protein Sequence Features|
|Protein-Nucleic Acid Interactions|