RRC ID 44423
Author Koike M, Yutoku Y, Koike A.
Title The C-terminal region of Rad52 is essential for Rad52 nuclear and nucleolar localization, and accumulation at DNA damage sites immediately after irradiation.
Journal Biochem Biophys Res Commun
Abstract Rad52 plays essential roles in homologous recombination (HR) and repair of DNA double-strand breaks (DSBs) in Saccharomyces cerevisiae. However, in vertebrates, knockouts of the Rad52 gene show no hypersensitivity to agents that induce DSBs. Rad52 localizes in the nucleus and forms foci at a late stage following irradiation. Ku70 and Ku80, which play an essential role in nonhomologous DNA-end-joining (NHEJ), are essential for the accumulation of other core NHEJ factors, e.g., XRCC4, and a HR-related factor, e.g., BRCA1. Here, we show that the subcellular localization of EYFP-Rad52(1-418) changes dynamically during the cell cycle. In addition, EYFP-Rad52(1-418) accumulates rapidly at microirradiated sites and colocalizes with the DSB sensor protein Ku80. Moreover, the accumulation of EYFP-Rad52(1-418) at DSB sites is independent of the core NHEJ factors, i.e., Ku80 and XRCC4. Furthermore, we observed that EYFP-Rad52(1-418) localizes in nucleoli in CHO-K1 cells and XRCC4-deficient cells, but not in Ku80-deficient cells. We also found that Rad52 nuclear localization, nucleolar localization, and accumulation at DSB sites are dependent on eight amino acids (411-418) at the end of the C-terminal region of Rad52 (Rad52 CTR). Furthermore, basic amino acids on Rad52 CTR are highly conserved among mammalian, avian, and fish homologues, suggesting that Rad52 CTR is important for the regulation and function of Rad52 in vertebrates. These findings also suggest that the mechanism underlying the regulation of subcellular localization of Rad52 is important for the physiological function of Rad52 not only at a late stage following irradiation, but also at an early stage.
Volume 435(2)
Pages 260-6
Published 2013-5-31
DOI 10.1016/j.bbrc.2013.04.067
PII S0006-291X(13)00706-7
PMID 23639616
MeSH Animals CHO Cells Cell Nucleus / physiology* Cell Nucleus / radiation effects* Cricetinae Cricetulus DNA Damage / physiology* Protein Structure, Tertiary Rad52 DNA Repair and Recombination Protein / chemistry* Rad52 DNA Repair and Recombination Protein / metabolism* Structure-Activity Relationship
IF 2.705
Times Cited 6
Human and Animal Cells