Rfc5, a replication factor C component, is required for regulation of Rad53 protein kinase in the yeast checkpoint pathway.
The RFC5 gene encodes a small subunit of replication factor C (RFC) complex in Saccharomyces cerevisiae. We have previously shown that a temperature-sensitive (ts) rfc5-1 mutation is impaired in the S-phase checkpoint. In this report, we show that the rfc5-1 mutation is sensitive to DNA-damaging agents. RFC5 is necessary for slowing the S-phase progression in response to DNA damage. The phosphorylation of the essential central transducer, Rad53 protein kinase, is reduced in response to DNA damage in rfc5-1 mutants during the S phase. Furthermore, the inducibility of RNR3 transcription in response to DNA damage is dependent on RFC5. It has been shown that phosphorylation of Rad53 is controlled by Mec1 and Tel1, members of the subfamily of ataxia-telangiectasia mutated (ATM) kinases. We also demonstrate that overexpression of TEL1 suppresses the ts growth defect and DNA damage sensitivity of rfc5-1 mutants and restores phosphorylation of Rad53 and RNR3 induction in response to DNA damage in rfc5-1. Our results, together with the observation that overexpression of RAD53 suppresses the defects of the rfc5-1 mutation, suggest that Rfc5 is part of a mechanism transducing the DNA damage signal to the activation of the central transducer Rad53.
Sugimoto
K
K
Department of Molecular Biology, Faculty of Science, Nagoya University, Japan.
Ando
S
S
Shimomura
T
T
Matsumoto
K
K
D018797:Cell Cycle Proteins; D064447:Checkpoint Kinase 2; D004249:DNA Damage / Q000502:physiology; D004261:DNA Replication; D004268:DNA-Binding Proteins / Q000235:genetics / Q000502:physiology*; D005656:Fungal Proteins / Q000235:genetics / Q000502:physiology*; D016195:G2 Phase / Q000502:physiology; D015966:Gene Expression Regulation, Fungal / Q000502:physiology; D005800:Genes, Fungal / Q000502:physiology; D018398:Homeodomain Proteins; D006918:Hydroxyurea / Q000494:pharmacology; D008741:Methyl Methanesulfonate / Q000494:pharmacology; D015778:Minor Histocompatibility Antigens; D009153:Mutagens / Q000494:pharmacology; D009154:Mutation; D010766:Phosphorylation; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000235:genetics / Q000502:physiology; D011494:Protein Kinases / Q000378:metabolism*; D017346:Protein Serine-Threonine Kinases; D019253:Proto-Oncogene Proteins c-bcl-2; D011836:Radiation Tolerance; D051818:Replication Protein C; D012097:Repressor Proteins; D016196:S Phase / Q000502:physiology*; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000254:growth & development / Q000528:radiation effects; D029701:Saccharomyces cerevisiae Proteins; D015398:Signal Transduction / Q000502:physiology*; D013696:Temperature; D015533:Transcriptional Activation / Q000502:physiology; D014466:Ultraviolet Rays
C096816:BCL2-related protein A1; D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; D018398:Homeodomain Proteins; C096063:MATA1 protein, S cerevisiae; D015778:Minor Histocompatibility Antigens; D009153:Mutagens; D019253:Proto-Oncogene Proteins c-bcl-2; D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins; D008741:Methyl Methanesulfonate; D011494:Protein Kinases; D017853:Phosphotransferases (Alcohol Group Acceptor); D064447:Checkpoint Kinase 2; D017346:Protein Serine-Threonine Kinases; C067022:RAD53 protein, S cerevisiae; D051818:Replication Protein C; D006918:Hydroxyurea