Chromatin-associated protein involved in DNA repair by promoting homologous recombination (HR). Binds double-stranded DNA (dsDNA) and secondary DNA structures, such as D-loop structures, but with less affinity than RAD51AP1. Does not interact with RAD51. Phosphorylated in an ATM-dependent manner in response to DNA damage. Phosphorylated by CDK1 and casein kinase.