NABP2
Function
Component of the SOSS complex, a multiprotein complex that functions downstream of the MRN complex to promote DNA repair and G2/M checkpoint (PubMed:25249620). In the SOSS complex, acts as a sensor of single-stranded DNA that binds to single-stranded DNA, in particular to polypyrimidines. The SOSS complex associates with DNA lesions and influences diverse endpoints in the cellular DNA damage response including cell-cycle checkpoint activation, recombinational repair and maintenance of genomic stability. Required for efficient homologous recombination-dependent repair of double-strand breaks (DSBs) and ATM-dependent signaling pathways.
Post-translational modifications
Phosphorylated by ATM in response to DNA damage. Phosphorylation prevents degradation by the proteasome, hence stabilization of the protein and accumulation within cells.
Ubiquitinated in a FBXL5-dependent manner, leading to proteasomal degradation.
Sequence Similarities
Belongs to the SOSS-B family. SOSS-B1 subfamily.
Cellular localization
- Nucleus
- Localizes to nuclear foci following DNA damage. Foci formation is not cell-cycle dependent. Partial colocalization with RAD51 after ionizing radiation treatment.
Alternative names
OBFC2B, SSB1, LP3587, NABP2, SOSS complex subunit B1, Nucleic acid-binding protein 2, Oligonucleotide/oligosaccharide-binding fold-containing protein 2B, Sensor of single-strand DNA complex subunit B1, Sensor of ssDNA subunit B1, Single-stranded DNA-binding protein 1, SOSS-B1, hSSB1