53BP1: Proteins and Enzymes

53BP1 (p53-binding protein 1) is a nuclear protein originally identified by its ability to bind p53. 53BP1 contains BRCA1 carboxy-terminal (BRCT) domains, regions that are present in multiple proteins involved in the genotoxic stress response which may serve to facilitate protein-protein interactions. 53BP1 is one of several BRCT-containing proteins recruited to sites of DNA damage to create a protein scaffold for further assembly of signaling complexes.