PCNA interacts with hHus1/hRad9 in response to DNA damage and replication inhibition.
The hHus1 and several hRad proteins are involved in the control of DNA integrity checkpoints, although the mechanisms underlying these processes are unknown. Using a yeast two-hybrid system to detect protein-protein interactions, we found that human proliferating cell nuclear antigen (PCNA), a protein known to function in both DNA replication and repair, interacts with the human checkpoint-related protein Hus1 (hHus1). In human skin fibroblast cells, exposure to ionizing radiation of hydroxyurea triggers translocation of hHus1 from the cytosol to the nucleus, where it associates with PCNA as well as another checkpoint protein, hRad9. This nuclear translocation and the complex formation or hHus1 with PCNA and hRad9 correlate closely with changes in cell cycle distribution in response to radiation exposure. These results suggest that this multi-protein complex may be important for coordinating cell-cycle progression, DNA replication and repair of damaged DNA.
Komatsu
K
K
Drug Discovery Program, H. Lee Moffitt Cancer Center and Research Institute, 12902 Magnolia Drive, Tampa, Florida, FL 33612, USA.
Wharton
W
W
Hang
H
H
Wu
C
C
Singh
S
S
Lieberman
H B
HB
Pledger
W J
WJ
Wang
H G
HG
D021581:Active Transport, Cell Nucleus / Q000187:drug effects / Q000528:radiation effects; D002453:Cell Cycle / Q000187:drug effects / Q000528:radiation effects; D018797:Cell Cycle Proteins / Q000378:metabolism*; D002455:Cell Division / Q000187:drug effects / Q000528:radiation effects; D002460:Cell Line; D002467:Cell Nucleus / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects; D002478:Cells, Cultured; D003593:Cytoplasm / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects; D004249:DNA Damage / Q000528:radiation effects; D004261:DNA Replication / Q000187:drug effects; D005347:Fibroblasts; D005720:Gamma Rays; D006801:Humans; D006918:Hydroxyurea / Q000494:pharmacology; D046911:Macromolecular Substances; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism*; D011485:Protein Binding / Q000187:drug effects / Q000528:radiation effects; D029702:Schizosaccharomyces pombe Proteins; D012867:Skin; D020798:Two-Hybrid System Techniques
D018797:Cell Cycle Proteins; D046911:Macromolecular Substances; D018809:Proliferating Cell Nuclear Antigen; D029702:Schizosaccharomyces pombe Proteins; C106332:hus1 protein, S pombe; C069930:rad9 protein; D006918:Hydroxyurea