Sulfolobus tokodaii RadA paralog,stRadC2,is involved in DNA recombination via interaction with RadA and Hjc  

作　　者：WANG Lei SHENG DuoHong HAN WenYuan HUANG Bin ZHU ShanShan NI JinFeng LI Jia SHEN YuLong 

机构地区：[1]State Key Laboratory of Microbial Technology,Shandong University,Jinan 250100,China [2]College of Pharmacy,Shandong University of Chinese Medicine,Jinan 250014,China

出　　处：《Science China(Life Sciences)》2012年第3期261-267,共7页中国科学（生命科学英文版）

基　　金：supported by the National Natural Science Foundation of China (Grant Nos. 3093002 and 30870046 to Shen YuLong,and 30700011 to Sheng DuoHong);the Promotive Research Fund for Excellent Young and Middle-aged Scientists of Shandong Province (Grant No. BS2010SW014 to Sheng DuoHong)

摘　　要：Rad51/RadA paralogs found in eukaryotes and euryarchaea play important roles during recombination and repair,and mutations in one of the human Rad51 paralogs,Rad51C,are associated with breast and ovarian cancers.The hyperthermophilic crenarchaeon Sulfolobus tokodaii encodes four putative RadA paralogs and studies on these proteins may assist in understanding the functions of human Rad51 paralogs.Here,we report the biochemical characterization of stRadC2,a S.tokodaii RadA paralog.Pull-down assays revealed that the protein was able to interact with the recombinase,RadA,and the Holliday junction endonuclease,Hjc.stRadC2 inhibited the strand exchange activity of RadA and facilitated Hjc-mediated Holliday junction DNA cleavage in vitro.RT-PCR analysis revealed that stRadC2 transcription was immediately reduced after UV irradiation,but was restored to normal levels at the late stages of DNA repair.Our results suggest that stRadC2 may act as an anti-recombination factor in DNA recombinational repair in S.tokodaii.Rad51/RadA paralogs found in eukaryotes and euryarchaea play important roles during recombination and repair, and mutations in one of the human Rad51 paralogs, Rad51C, are associated with breast and ovarian cancers. The hyperthermophilic crenarchaeon Sulfolobus tokodaii encodes four putative RadA paralogs and studies on these proteins may assist in understand- ing the functions of human Rad51 paralogs. Here, we report the biochemical characterization of stRadC2, a S. tokodaii RadA paralog. Pull-down assays revealed that the protein was able to interact with the recombinase, RadA, and the Holliday junction endonuclease, Hjc. stRadC2 inhibited the strand exchange activity of RadA and facilitated Hjc-mediated Holliday junction DNA cleavage in vitro. RT-PCR analysis revealed that stRadC2 transcription was immediately reduced after UV irradiation, but was restored to normal levels at the late stages of DNA repair. Our results suggest that stRadC2 may act as an anti-recombination factor in DNA recombinational repair in S. tokodaii.

关 键 词：ARCHAEA SULFOLOBUS recombination RADA stRadC Hjc 

分 类 号：Q78[生物学—分子生物学] TQ330.67[化学工程—橡胶工业]