title: Role of Schizosaccharomyces pombe RecQ homolog, recombination, and checkpoint genes in UV damage tolerance.
abstract: The cellular responses to DNA damage are complex and include direct DNA repair pathways that remove the damage and indirect damage responses which allow cells to survive DNA damage that has not been, or cannot be, removed. We have identified the gene mutated in the rad12.502 strain as a Schizosaccharomyces pombe recQ homolog. The same gene (designated rqh1) is also mutated in the hus2.22 mutant. We show that Rqhl is involved in a DNA damage survival mechanism which prevents cell death when UV-induced DNA damage cannot be removed. This pathway also requires the correct functioning of the recombination machinery and the six checkpoint rad gene products plus the Cdsl kinase. Our data suggest that Rqh1 operates during S phase as part of a mechanism which prevents DNA damage causing cell lethality. This process may involve the bypass of DNA damage sites by the replication fork. Finally, in contrast with the reported literature, we do not find that rqh1 (rad12) mutant cells are defective in UV dimer endonuclease activity.
authors.affiliation: School of Biological Sciences, Sussex University, Falmer, Brighton, United Kingdom. j.m.murray@sussex.ac.uk
authors.forename: J M
authors.initials: JM
authors.lastname: Murray
authors.forename: H D
authors.initials: HD
authors.lastname: Lindsay
authors.forename: C A
authors.initials: CA
authors.lastname: Munday
authors.forename: A M
authors.initials: AM
authors.lastname: Carr
mesh_terms: D000251:Adenosine Triphosphatases / Q000235:genetics*; D004249:DNA Damage; D004265:DNA Helicases / Q000235:genetics* / Q000378:metabolism; D004260:DNA Repair / Q000235:genetics / Q000502:physiology; D004261:DNA Replication; D004271:DNA, Fungal / Q000235:genetics / Q000378:metabolism / Q000528:radiation effects; D005057:Eukaryotic Cells; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism; D017353:Gene Deletion; D005800:Genes, Fungal; D008954:Models, Biological; D009154:Mutation; D016366:Open Reading Frames; D053484:RecQ Helicases; D011995:Recombination, Genetic; D012568:Schizosaccharomyces / Q000235:genetics* / Q000378:metabolism / Q000528:radiation effects*; D029702:Schizosaccharomyces pombe Proteins; D014466:Ultraviolet Rays
chemical_list: D004271:DNA, Fungal; D005656:Fungal Proteins; D029702:Schizosaccharomyces pombe Proteins; D000251:Adenosine Triphosphatases; D004265:DNA Helicases; D053484:RecQ Helicases; C106462:Rqh1 protein, S pombe