Novel role for the C terminus of Saccharomyces cerevisiae Rev1 in mediating protein-protein interactions.
The Saccharomyces cerevisiae REV3/7-encoded polymerase zeta and Rev1 are central to the replicative bypass of DNA lesions, a process called translesion synthesis (TLS). While yeast polymerase zeta extends from distorted DNA structures, Rev1 predominantly incorporates C residues from across a template G and a variety of DNA lesions. Intriguingly, Rev1 catalytic activity does not appear to be required for TLS. Instead, yeast Rev1 is thought to participate in TLS by facilitating protein-protein interactions via an N-terminal BRCT motif. In addition, higher eukaryotic homologs of Rev1 possess a C terminus that interacts with other TLS polymerases. Due to a lack of sequence similarity, the yeast Rev1 C-terminal region, located after the polymerase domain, had initially been thought not to play a role in TLS. Here, we report that elevated levels of the yeast Rev1 C terminus confer a strong dominant-negative effect on viability and induced mutagenesis after DNA damage, highlighting the crucial role that the C terminus plays in DNA damage tolerance. We show that this phenotype requires REV7 and, using immunoprecipitations from crude extracts, demonstrate that, in addition to the polymerase-associated domain, the extreme Rev1 C terminus and the BRCT region of Rev1 mediate interactions with Rev7.
D'Souza
Sanjay
S
Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Walker
Graham C
GC
D020816:Amino Acid Motifs; D002470:Cell Survival; D004249:DNA Damage; D004259:DNA-Directed DNA Polymerase / Q000235:genetics / Q000378:metabolism; D009154:Mutation; D009713:Nucleotidyltransferases / Q000235:genetics / Q000378:metabolism*; D010446:Peptide Fragments / Q000235:genetics / Q000378:metabolism*; D010641:Phenotype; D017434:Protein Structure, Tertiary; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism* / Q000528:radiation effects; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D014466:Ultraviolet Rays; D000099270:Y-Family DNA Polymerases
D004259:DNA-Directed DNA Polymerase; D009713:Nucleotidyltransferases; D010446:Peptide Fragments; D029701:Saccharomyces cerevisiae Proteins; C092219:REV7 protein, S cerevisiae; C100951:REV1 protein, S cerevisiae; D000099270:Y-Family DNA Polymerases