title: Mutations in the gene encoding the 34 kDa subunit of yeast replication protein A cause defective S phase progression.
abstract: The in vivo function of the 34 kDa subunit of yeast replication protein A (RPA), encoded by the RFA2 gene, has been studied by analyzing the effect of Rpa34 depletion and by producing and characterizing rfa2 temperature-sensitive mutants. We show that unbalanced stoichiometry of the RPA subunits does not affect cell growth and cell cycle progression until the level of Rpa34 becomes rate-limiting, at which point cells arrest with a late S/G2 DNA content. Rpa34 is involved in DNA replication in vivo, since rfa2 ts mutants are defective in S phase progression and ARS plasmid stability, and rfa2 pol1 double mutants are non-viable. Moreover, when shifted to the restrictive temperature, about 50% of the rfa2 mutant cells rapidly die while traversing the S phase and the surviving cells arrest in late S/G2 at the RAD9 checkpoint. Finally, rfa2 mutant cells have a mutator and hyper-recombination phenotype and are more sensitive to hydroxyurea and methyl-methane-sulfonate than wild-type cells.
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics; D001483:Base Sequence; D002453:Cell Cycle / Q000235:genetics; D018797:Cell Cycle Proteins; D016923:Cell Death / Q000235:genetics; D002455:Cell Division / Q000235:genetics; D004257:DNA Polymerase II; D004260:DNA Repair; D004261:DNA Replication; D004268:DNA-Binding Proteins / Q000235:genetics*; D005656:Fungal Proteins / Q000235:genetics*; D016195:G2 Phase / Q000235:genetics; D016695:Glycosyltransferases / Q000235:genetics*; D008969:Molecular Sequence Data; D009154:Mutation; D010957:Plasmids / Q000737:chemistry; D051716:Replication Protein A; D012097:Repressor Proteins / Q000235:genetics; D016196:S Phase / Q000235:genetics*; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins; D013696:Temperature; D014157:Transcription Factors
chemical_list: D001426:Bacterial Proteins; D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; C082727:RFA2 protein, S cerevisiae; D051716:Replication Protein A; D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; C060486:methionine repressor protein, Bacteria; C069930:rad9 protein; D016695:Glycosyltransferases; D004257:DNA Polymerase II