Component of the MMS22L-TONSL complex, a complex that promotes homologous recombination-mediated repair of double-strand breaks (DSBs) at stalled or collapsed replication forks. The MMS22L-TONSL complex is required to maintain genome integrity during DNA replication. It mediates the assembly of RAD51 filaments on single-stranded DNA (ssDNA): the MMS22L-TONSL complex is recruited to DSBs following histone replacement by histone chaperones and eviction of the replication protein A complex (RPA/RP-A) from DSBs. Following recruitment to DSBs, the TONSL-MMS22L complex promotes recruitment of RAD51 filaments and subsequent homologous recombination. Within the complex, MMS22L acts by binding ssDNA. Component of the MMS22L-TONSL complex, a complex at least composed of MMS22L and TONSL/NFKBIL2. Interacts with RAD51; interaction is direct. Localizes to DNA damage sites, accumulates at stressed replication forks. Recruited to stalled or collapsed replication forks; directly binds replication protein A complex (RPA/RP-A)-coated single-stranded DNA (ssDNA). Degraded by the ubiquitin-proteasome system upon replication stress. Belongs to the MMS22 family. MMS22L subfamily.