The active site residues Gln55 and Arg73 play a key role in DNA damage bypass by S. cerevisiae Pol η.

ABSTRACT: Eukaryotic DNA polymerase eta (Pol η) plays a key role in the efficient and accurate DNA translesion synthesis (TLS) opposite UV-induced thymine dimers. Pol η is also involved in bypass of many other DNA lesions but possesses low fidelity on undamaged DNA templates. To better understand the mechanism of DNA synthesis by Pol η we investigated substitutions of evolutionary conserved active site residues Gln55 and Arg73 in Saccharomyces cerevisiae Pol η. We analyzed the efficiency and fidelity of DNA synthesis by the mutant Pol η variants opposite thymine dimers, abasic site, thymine glycol, 8-oxoguanine and on undamaged DNA. Substitutions Q55A and R73A decreased the catalytic activity and significantly affected DNA damage bypass by Pol η. In particular, the Q55A substitution reduced the effi

SUBMITTER: Boldinova EO 

PROVIDER: S-EPMC6037775 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature