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 (PubMed:21055983, PubMed:21055984, PubMed:21055985, PubMed:21113133, PubMed:26527279, PubMed:27338793, PubMed:29478807). The MMS22L-TONSL complex is required to maintain genome integrity during DNA replication (PubMed:21055983, PubMed:21055984, PubMed:21055985, PubMed:27797818). 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 (PubMed:21055983, PubMed:21055984, PubMed:21055985, PubMed:29478807). Following recruitment to DSBs, the TONSL-MMS22L complex promotes recruitment of RAD51 filaments and subsequent homologous recombination (PubMed:27797818, PubMed:29478807). Within the complex, MMS22L acts by binding ssDNA (PubMed:27797818). Component of the MMS22L-TONSL complex, a complex at least composed of MMS22L and TONSL/NFKBIL2 (PubMed:21055983, PubMed:21055984, PubMed:21055985, PubMed:21113133, PubMed:27797818). Interacts with RAD51; interaction is direct (PubMed:27797818). Localizes to DNA damage sites, accumulates at stressed replication forks (PubMed:21055983, PubMed:21055984, PubMed:27797818). Recruited to stalled or collapsed replication forks; directly binds replication protein A complex (RPA/RP-A)-coated single-stranded DNA (ssDNA) (PubMed:27797818). Degraded by the ubiquitin-proteasome system upon replication stress. Belongs to the MMS22 family. MMS22L subfamily.