Silencing of p29 affects DNA damage responses with UV irradiation.
Human p29 is a newly identified nuclear protein whose function is largely undetermined. We found that p29 associated with chromatin, interacted with MCM3, and localized with proliferating cell nuclear antigen foci in the S phase. Silencing of p29 using small interfering RNA duplexes reduced DNA synthesis and increased the expression of p107, a member of the RB family, and of cyclin-dependent kinase inhibitor p21, accompanied with a decreased expression of DNA polymerase alpha. Lethal events consisting of premature chromatin condensation with a reduced Chk1 phosphorylation were observed in p29-depleted cells in response to UV irradiation. Intriguingly, the phosphorylation of ataxia telangectasia-mutated kinases at S1981 was suppressed in p29-depleted HeLa cells with UV irradiation, but not in hydroxyurea- and ionizing radiation-treated cells. Taken together, these results reveal a novel function of p29 in the regulation of DNA replication checkpoint responses.
Chu
Po-Chen
PC
Institute of Biochemical Sciences, National Taiwan University, Taipei, Taiwan.
Yang
Yuh-Cheng
YC
Lu
Yen-Ta
YT
Chen
Hsiang-Ting
HT
Yu
Lung-Chih
LC
Chang
Mau-Sun
MS
D017209:Apoptosis / Q000528:radiation effects; D004247:DNA / Q000235:genetics*; D004249:DNA Damage; D004261:DNA Replication / Q000528:radiation effects; D020868:Gene Silencing; D006367:HeLa Cells; D006801:Humans; D008938:Mitosis / Q000528:radiation effects; D009687:Nuclear Proteins / Q000172:deficiency / Q000235:genetics*; D034741:RNA, Small Interfering / Q000235:genetics / Q000528:radiation effects; D016601:RNA-Binding Proteins; D014466:Ultraviolet Rays
C418608:GCIP-interacting protein p29, human; D009687:Nuclear Proteins; D034741:RNA, Small Interfering; D016601:RNA-Binding Proteins; D004247:DNA