AP-endonuclease 1 sculpts DNA through an anchoring tyrosine residue on the DNA intercalating loop.

ABSTRACT: Base excision repair (BER) maintains genomic stability through the repair of DNA damage. Within BER, AP-endonuclease 1 (APE1) is a multifunctional enzyme that processes DNA intermediates through its backbone cleavage activity. To accomplish these repair activities, APE1 must recognize and accommodate several diverse DNA substrates. This is hypothesized to occur through a DNA sculpting mechanism where structural adjustments of the DNA substrate are imposed by the protein; however, how APE1 uniquely sculpts each substrate within a single rigid active site remains unclear. Here, we utilize structural and biochemical approaches to probe the DNA sculpting mechanism of APE1, specifically by characterizing a protein loop that intercalates the minor groove of the DNA (termed the intercalating loop

SUBMITTER: Hoitsma NM 

PROVIDER: S-EPMC7367167 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature