title: Sulfolobus tokodaii RadA paralog, stRadC2, is involved in DNA recombination via interaction with RadA and Hjc.
abstract: 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.
authors.affiliation: State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Wang
authors.forename: DuoHong
authors.initials: D
authors.lastname: Sheng
authors.forename: WenYuan
authors.initials: W
authors.lastname: Han
authors.forename: Bin
authors.initials: B
authors.lastname: Huang
authors.forename: ShanShan
authors.initials: S
authors.lastname: Zhu
authors.forename: JinFeng
authors.initials: J
authors.lastname: Ni
authors.forename: Jia
authors.initials: J
authors.lastname: Li
authors.forename: YuLong
authors.initials: Y
authors.lastname: Shen
mesh_terms: D000595:Amino Acid Sequence; D019843:Archaeal Proteins / Q000737:chemistry* / Q000378:metabolism / Q000502:physiology; D004247:DNA / Q000235:genetics*; D004260:DNA Repair; D045566:DNA, Cruciform; D004277:DNA, Single-Stranded / Q000235:genetics; D004268:DNA-Binding Proteins / Q000378:metabolism*; D020745:Genome, Archaeal; D006801:Humans; D008969:Molecular Sequence Data; D010957:Plasmids / Q000378:metabolism; D017434:Protein Structure, Tertiary; D051135:Rad51 Recombinase / Q000737:chemistry; D011995:Recombination, Genetic; D012441:Saccharomyces cerevisiae / Q000235:genetics; D017386:Sequence Homology, Amino Acid; D016944:Sulfolobus / Q000378:metabolism*; D013997:Time Factors
chemical_list: D019843:Archaeal Proteins; D045566:DNA, Cruciform; D004277:DNA, Single-Stranded; D004268:DNA-Binding Proteins; C117252:RadA protein, archaeal; D004247:DNA; C495153:RAD51 protein, human; D051135:Rad51 Recombinase