Homologous pairing and ring and filament structure formation activities of the human Xrcc2*Rad51D complex.
The Xrcc2 and Rad51D/Rad51L3 proteins, which belong to the Rad51 paralogs, are required for homologous recombinational repair (HRR) in vertebrates. The Xrcc2 and Rad51D/Rad51L3 genes, whose products interact with each other, have essential roles in ensuring normal embryonic development. In the present study, we coexpressed the human Xrcc2 and Rad51D/Rad51L3 proteins (Xrcc2 and Rad51D, respectively) in Escherichia coli, and purified the Xrcc2*Rad51D complex to homogeneity. The Xrcc2 small middle dotRad51D complex catalyzed homologous pairing between single-stranded and double-stranded DNA, similar to the function of the Xrcc3*Rad51C complex, which is another complex of the Rad51 paralogs. An electron microscopic analysis showed that Xrcc2*Rad51D formed a multimeric ring structure in the absence of DNA. In the presence of ssDNA, Xrcc2*Rad51D formed a filamentous structure, which is commonly observed among the human homologous pairing proteins, Rad51, Rad52, and Xrcc3*Rad51C.
Kurumizaka
Hitoshi
H
RIKEN Genomic Sciences Center, 1-7-22 Suehiro-cho, Tsurumi, Yokohama 230-0045, Japan.
Ikawa
Shukuko
S
Nakada
Maki
M
Enomoto
Rima
R
Kagawa
Wataru
W
Kinebuchi
Takashi
T
Yamazoe
Mitsuyoshi
M
Yokoyama
Shigeyuki
S
Shibata
Takehiko
T
D002384:Catalysis; D002942:Circular Dichroism; D002945:Cisplatin / Q000494:pharmacology*; D003432:Cross-Linking Reagents / Q000494:pharmacology; D004247:DNA / Q000378:metabolism; D004277:DNA, Single-Stranded / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000737:chemistry*; D004305:Dose-Response Relationship, Drug; D004926:Escherichia coli / Q000378:metabolism; D006801:Humans; D008854:Microscopy, Electron; D009698:Nucleoproteins / Q000378:metabolism; D011485:Protein Binding
D003432:Cross-Linking Reagents; D004277:DNA, Single-Stranded; D004268:DNA-Binding Proteins; D009698:Nucleoproteins; C112629:RAD51D protein, human; C113187:XRCC2 protein, human; D004247:DNA; D002945:Cisplatin