A novel Saccharomyces cerevisiae gene SRL5 is involved in the regulation of dNTP biosynthesis

초록

In an attempt to identify novel genes involved in DNA metabolism, we analyzed the proteins that were eluted from the single-stranded DNA cellulose column. The eluted proteins included replication and/or repair proteins (RPA, Rim1, RFC, ligase, CDC45, msh2, and msh3), histones, and some uncharacterized proteins. SRL5 (YDL156W), one of these uncharacterized proteins, is a putative protein of unknown function, containing three WD domains (WD-40 repeat). We found that deletion of this gene suppress the lethality of mutations of the essential S phase checkpoint genes, RAD53 and LCD1. We also found that the srl5D mutant cells were resistant to hydroxyurea and evidenced higher dNTP levels than were observed in the wild-type cells. The mutant cells also showed a significantly faster growth rate and higher dNTP levels at low temperature (16oC) than were observed in the wild-type cells, whereas we detected no differences in the growth rate at 30oC. TAP affinity purification showed that Srl5 interacts with RPA and histones. The function of Srl5 was discussed on the basis of these observations. (This work supported by grant R01-2007-000-20380-0 from KOSEF)