Structure-specific DNA-binding protein involved in DNA repair by promoting RAD51-mediated homologous recombination (  ). Acts by stimulating D-Loop formation by RAD51: specifically enhances joint molecule formation through its structure-specific DNA interaction and its interaction with RAD51 (, ). Binds single-stranded DNA (ssDNA), double-stranded DNA (dsDNA) and secondary DNA structures, such as D-loop structures: has a strong preference for branched-DNA structures that are obligatory intermediates during joint molecule formation ( , ). Cooperates with WDR48/UAF1 to stimulate RAD51-mediated homologous recombination: both WDR48/UAF1 and RAD51AP1 have coordinated role in DNA-binding during homologous recombination and DNA repair ( ). WDR48/UAF1 and RAD51AP1 also have a coordinated role in DNA-binding to promote USP1-mediated deubiquitination of FANCD2 . Also involved in meiosis by promoting DMC1-mediated homologous meiotic recombination . Key mediator of alternative lengthening of telomeres (ALT) pathway, a homology-directed repair mechanism of telomere elongation that controls proliferation in aggressive cancers, by stimulating homologous recombination . May also bind RNA; additional evidences are however required to confirm RNA-binding in vivo .
Subcellular locations: Chromosome, Nucleus, Chromosome, Telomere
Colocalizes with RAD51 to multiple nuclear foci (By similarity). Colocalizes with DMC1 on meiotic chromatin (By similarity).
Highly expressed in testis and thymus . Lower levels in colon and small intestine . Little or no expression in spleen, prostate, ovary and peripheral blood leukocytes .