Hrq1 functions independently of Sgs1 to preserve genome integrity in Saccharomyces cerevisiae

作者：Choi Do Hee; Lee Rina; Kwon Sung Hun; Bae Sung Ho^*

来源：Journal of Microbiology, 2013, 51(1): 105-112.

DOI：10.1007/s12275-013-3048-2

• Hrq1
• RecQ helicase
• DNA helicase
• RECQL4 orthologue
• Sgs1
• recombination

Maintenance of genome stability in eukaryotes involves a number of conserved proteins, including RecQ helicases, which play multiple roles at various steps in homologous recombination and DNA repair pathways. Sgs1 has been described as the only RecQ helicase in lower eukaryotes. However, recent studies revealed the presence of a second RecQ helicase, Hrq1, which is most homologous to human RECQL4. Here we show that hrq1 Delta mutation resulted in increased mitotic recombination and spontaneous mutation in Saccharomyces cerevisiae, and sgs1 Delta mutation had additive effects on the phenotypes of hrq1 Delta. We also observed that the hrq1 Delta mutant was sensitive to 4-nitroquinoline 1-oxide and cisplatin, which was not complemented by overexpression of Sgs1. In addition, the hrq1 Delta sgs1 Delta double mutant displayed synthetic growth defect as well as a shortened chronological life span compared with the respective single mutants. Analysis of the type of age-dependent Can(r) mutations revealed that only point mutations were found in hrq1 Delta, whereas significant numbers of gross deletion mutations were found in sgs1 Delta. Our results suggest that Hrq1 is involved in recombination and DNA repair pathways in S. cerevisiae independent of Sgs1.

• 出版日期2013-2