Chromatin-associated protein involved in DNA repair by promoting homologous recombination (HR) (PubMed:26323318). Binds double-stranded DNA (dsDNA) and secondary DNA structures, such as D-loop structures, but with less affinity than RAD51AP1 (PubMed:26323318). Does not interact with RAD51. Widely expressed, with highest levels in thyroid gland, prostate and uterus and in fetal liver, thymus and lung. Phosphorylated in an ATM-dependent manner in response to DNA damage (PubMed:26323318). Phosphorylated by CDK1 and casein kinase (PubMed:11298763). Truncated C-terminus.