2010-2006
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The catalytic function of the Rev1 dCMP transferase is required in a lesion-specific manner for translesion synthesis and base damage-induced mutagenesis(Nucleic Acids Research, 2010, doi:10.1093/nar/gkq225)

ABSTRACT
The Rev1-Polf pathway is believed to be the major mechanism of translesion DNA synthesis and base damage-induced mutagenesis in eukaryotes. Whilei t is widely believed that Rev1 plays a non-catalytic function in translesion synthesis, the role of its dCMP transferase activity remains uncertain. To determine the relevance of its catalytic function in translesion synthesis, we separated the Rev1d CMP transferase activity from its non-catalyticf unction in yeast. This was achieved by mutatingt wo conserved amino acid residues in the catalytic domain of Rev1, i.e. D467A/E468A, where its catalyticf unction was abolished but its non-catalyticf unction remained intact. In this mutant strain,w hereas translesion synthesis and mutagenesis of UV radiation were fully functional, those of a site-specific 1,N6-ethenoadenine were severelyd eficient. Specifically, the predominant A!G mutations resulting from C insertion opposite the lesionw ere abolished. Therefore, translesion synthesisa nd mutagenesis of 1,N6-ethenoadenine require the catalytic function of the Rev1 dCMP transferase,i n contrast to those of UV lesions, which only require the non-catalytic function of Rev1. These results show that the catalytic function of the Rev1 dCMPt ransferase is required in a lesion-specific mannerf or translesion synthesis and base damage-inducedm
u
tagenesis.