RAD51B:RAD51C binds single-stranded DNA

The complex of Rad51B and Rad51C binds single-stranded DNA and hydrolyses ATP (Sigurdsson et al. 2001). Rad51B and Rad51C are both required for recombination and DNA double-strand break repair in vivo. The complex cannot substitute for RPA but enhances Rad51/RPA mediated repair. The proposed mechanism for this is that Rad51b:Rad51C partially overcomes the suppressive effect of RPA on Rad51-catalyzed DNA pairing and strand exchange; RPA is an important accessory factor for Rad51-mediated homologous DNA pairing and strand exchange, but it can also compete with Rad51 for binding sites on the ssDNA template, which, when allowed to occur, suppresses pairing and strand exchange efficiency markedly (Sung et al. 2000).

Rad51B与Rad51C的复合物能够结合单链DNA并水解ATP（Sigurdsson等，2001年）。Rad51B和Rad51C在体内对于重组及DNA双链断裂修复均属必需。此复合物虽不能替代RPA，却能增强Rad51/RPA介导的修复作用。其潜在机制在于Rad51b:Rad51C部分克服了RPA对Rad51催化DNA配对和链交换的抑制作用；RPA是Rad51介导的同源DNA配对和链交换的重要辅助因子，但亦可能竞争Rad51在ssDNA模板上的结合位点，当此竞争发生时，会显著降低配对和链交换的效率（Sung等，2000年）。