Abstract
Mismatch repair（MMR）proteins contribute to genome integrity by correcting replication errors. We performed functional assay of many MLH1 mutants to clarify the pathogenicity of hereditary nonpolyposis colorectal cancer. The mutants were categorized by our two-type of functional assay. In higher eukaryotes, MMR proteins also regulate the cellular response to specific DNA damage caused by oxidization, alkylation or crosslinking. Previous studies have shown that MMR proteins were involved in the activation of apoptosis through p53- dependent and p53-independent mechanisms. MMRdeficient cells are known to be resistant to several DNA-damaging agents and exhibit various defects in the induction of p53 and its related p73 proteins, which are activators of apoptosis.
