Article

In vitro studies of DNA mismatch repair proteins.

Genetics & Biochemistry Branch, National Institutes of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
Analytical Biochemistry (Impact Factor: 2.31). 02/2011; 413(2):179-84. DOI: 10.1016/j.ab.2011.02.017
Source: PubMed

ABSTRACT The ability to monitor and characterize DNA mismatch repair activity in various mammalian cells is important for understanding mechanisms involved in mutagenesis and tumorigenesis. Since mismatch repair proteins recognize mismatches containing both normal and chemically altered or damaged bases, in vitro assays must accommodate a variety of mismatches in different sequence contexts. Here we describe the construction of DNA mismatch substrates containing G:T or O(6)meG:T mismatches, the purification of recombinant native human MutSα (MSH2-MSH6) and MutLα (MLH1-PMS2) proteins, and in vitro mismatch repair and excision assays that can be adapted to study mismatch repair in nuclear extracts from mismatch repair proficient and deficient cells.

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