The human oxidative DNA glycosylase NEIL1 excises psoralen-induced interstrand DNA cross-links in a three-stranded DNA structure.

ABSTRACT: Previously, we have demonstrated that human oxidative DNA glycosylase NEIL1 excises photoactivated psoralen-induced monoadducts but not genuine interstrand cross-links (ICLs) in duplex DNA. It has been postulated that the repair of ICLs in mammalian cells is mainly linked to DNA replication and proceeds via dual incisions in one DNA strand that bracket the cross-linked site. This process, known as "unhooking," enables strand separation and translesion DNA synthesis through the gap, yielding a three-stranded DNA repair intermediate composed of a short unhooked oligomer covalently bound to the duplex. At present, the detailed molecular mechanism of ICL repair in mammalian cells remains unclear. Here, we constructed and characterized three-stranded DNA structures containing a single ICL as su

SUBMITTER: Couve S 

PROVIDER: S-EPMC2673265 | biostudies-literature | 2009 May

REPOSITORIES: biostudies-literature