The mismatch repair endonuclease MutLα tethers duplex regions of DNA together and relieves DNA torsional tension.

ABSTRACT: In eukaryotic mismatch repair, MutS homologs recognize mismatches and recruit the MutLα endonuclease which introduces a nick in the newly replicated, error-containing DNA strand. The nick occurs in response to the mismatch, but at a site up to several hundred base pairs away. The MutLα nick promotes mismatch excision by an exonuclease (Exo1) or removal by the strand displacement activity of a DNA polymerase which may work in conjunction with a flap endonuclease. Models have suggested that MutL homolog endonucleases form oligomeric complexes which facilitate and are activated by strand capture mechanisms, although such models have never been explicitly tested. We present evidence that the mismatch repair MutLα endonuclease is activated by DNA-DNA associations and that it can use this proper

SUBMITTER: Witte SJ 

PROVIDER: S-EPMC10085691 | biostudies-literature | 2023 Apr

REPOSITORIES: biostudies-literature