Functional and physical interaction between Rad24 and Rfc5 in the yeast checkpoint pathways.
The RFC5 gene encodes a small subunit of replication factor C (RFC) complex in Saccharomyces cerevisiae and has been shown to be required for the checkpoints which respond to replication block and DNA damage. Here we describe the isolation of RAD24, known to play a role in the DNA damage checkpoint, as a dosage-dependent suppressor of rfc5-1. RAD24 overexpression suppresses the sensitivity of rfc5-1 cells to DNA-damaging agents and the defect in DNA damage-induced Rad53 phosphorylation. Rad24, like Rfc5, is required for the regulation of Rad53 phosphorylation in response to DNA damage. The Rad24 protein, which is structurally related to the RFC subunits, interacts physically with RFC subunits Rfc2 and Rfc5 and cosediments with Rfc5. Although the rad24Delta mutation alone does not cause a defect in the replication block checkpoint, it does enhance the defect in rfc5-1 mutants. Furthermore, overexpression of RAD24 suppresses the rfc5-1 defect in the replication block checkpoint. Taken together, our results demonstrate a physical and functional interaction between Rad24 and Rfc5 in the checkpoint pathways.
Shimomura
T
T
Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa-ku, Nagoya 464-0814, Japan.
Ando
S
S
Matsumoto
K
K
Sugimoto
K
K
D018797:Cell Cycle Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D064447:Checkpoint Kinase 2; D004249:DNA Damage; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D005656:Fungal Proteins / Q000737:chemistry / Q000378:metabolism; D005800:Genes, Fungal; D005838:Genotype; D018398:Homeodomain Proteins; D047908:Intracellular Signaling Peptides and Proteins; D007700:Kinetics; D008741:Methyl Methanesulfonate; D015778:Minor Histocompatibility Antigens; D016296:Mutagenesis; D009153:Mutagens; D010766:Phosphorylation; D011494:Protein Kinases / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases; D019253:Proto-Oncogene Proteins c-bcl-2; D051818:Replication Protein C; D012097:Repressor Proteins; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins; D008941:Spindle Apparatus / Q000235:genetics; D014466:Ultraviolet Rays
C096816:BCL2-related protein A1; D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; D018398:Homeodomain Proteins; D047908:Intracellular Signaling Peptides and Proteins; C096063:MATA1 protein, S cerevisiae; D015778:Minor Histocompatibility Antigens; D009153:Mutagens; D019253:Proto-Oncogene Proteins c-bcl-2; C088385:RAD24 protein, S cerevisiae; D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins; D008741:Methyl Methanesulfonate; D011494:Protein Kinases; D064447:Checkpoint Kinase 2; D017346:Protein Serine-Threonine Kinases; C067022:RAD53 protein, S cerevisiae; D051818:Replication Protein C