Plays a role in DNA double-strand break (DBS) repair via homologous recombination (HR). Serves as a scaffolding protein that helps to promote the recruitment of DNA-processing enzymes like the helicase BLM and recombinase RAD51 to site of DNA damage, and hence contributes to maintain genomic integrity (By similarity). Found in a complex, at least composed of BLM, RAD51 and SPIDR; the complex formation is mediated by SPIDR. Interacts (via C-terminal region) with BLM; the interaction is direct. Interacts with RAD51; the interaction is direct. Interacts (via the C-terminal region) with FIGNL1 (via N-terminal one-half region); the interaction is direct (By similarity). Together with BLM, is redistributed in discrete nuclear DNA damage-induced foci following hydroxyurea (HU) or camptothecin (CPT) treatment. Extended N-terminus.