MLH1 Antibody (YA290),MedChemexpress,HY-P80226

MLH1 heterodimerizes with PMS2 to form MutL alpha, a core component of the post-replicative DNA mismatch repair (MMR) system. Repair initiation involves binding of MutS alpha (MSH2-MSH6) or MutS beta (MSH2-MSH3) to dsDNA mismatches, followed by recruitment of MutL alpha to the heteroduplex. Ternary complex formation (MutL-MutS-heteroduplex) with RFC and PCNA activates PMS2's endonuclease activity, creating single-strand breaks near mismatches to enable EXO1 exonuclease-mediated degradation of the error-containing strand. DNA methylation prevents cleavage, ensuring correction exclusively targets the newly synthesized mutated strand. MutL alpha (MLH1-PMS2) physically interacts with DNA polymerase III clamp loader subunits, suggesting a role in polymerase recruitment to MMR sites. MLH1 also participates in DNA damage signaling, inducing cell cycle arrest or apoptosis upon severe damage. by similar: MLH1 forms MutL gamma (with MLH3) during meiosis.