Plays an essential role in homologous recombination (HR) which is a major pathway for repairing DNA double-strand breaks (DSBs), single-stranded DNA (ssDNA) gaps, and stalled or collapsed replication forks (PubMed:9774452, PubMed:24798879, PubMed:32457312, PubMed:11459989, PubMed:12205100, PubMed:27264870). Acts as a molecular motor during the homology search and guides RAD51 ssDNA along a donor dsDNA thereby changing the homology search from the diffusion-based mechanism to a motor-guided mechanism. Also plays an essential role in RAD51-mediated synaptic complex formation which consists of three strands encased in a protein filament formed once homology is recognized. Once DNA strand exchange occured, dissociates RAD51 from nucleoprotein filaments formed on dsDNA (By similarity). ATP + H2O = ADP + H(+) + phosphate Homohexamer (By similarity). Interacts (via N-terminus) with RAD51 (PubMed:9321665). Interacts with NAP1L1 (PubMed:24798879). Interacts with BRD9; this interaction orchestrates RAD51-RAD54 complex formation (PubMed:32457312). Expression increases approximately 3-fold in late G1 phase compared to other phases of the cell cycle. Acetylated. Acetylation promotes interaction with BRD9, and subsequently with RAD54, which is essential for homologous recombination (HR). Phosphorylated. Phosphorylation at Ser-572 by NEK1 specifically in G2 phase allows efficient removal of RAD51 filaments from DNA. Belongs to the SNF2/RAD54 helicase family.