mouse monoclonal IgG1; P2P-R Antibody (M56) is an IgG1 mouse monoclonal P2P-R antibody (also designated P2P-R antibody) that detects the P2P-R protein of mouse, rat and human origin by WB, IP, IF and IHC(P). P2P-R Antibody (M56) is available as both the non-conjugated anti-P2P-R antibody form, as well as multiple conjugated forms of anti-P2P-R antibody, including agarose, HRP, PE, FITC and multiple Alexa Fluor® conjugates. Rb protein and p53 are both cell cycle checkpoint components. Evidence suggests that p53 plays a role in regulating the phosphorylation of Rb by inducing p21 transcription, thus preventing Rb phosphorylation at the G1 to S transition. Protein-protein interactions seem to be central in p53 cellular activities, as previously demonstrated with MDM2 and SV40 large T antigen. Two novel proteins have been identified by their abilities to bind to p53 and/ or Rb. Human RBQ-1 (also designated RBBP6) has been cloned as a novel protein that binds to the retinoblastoma (Rb) gene product. A related mouse protein, P2P-R, also designated PACT (for p53 associated cellular protein-testis derived), has been shown to bind to both Rb and p53. Recombinant P2P-R binds to wildtype p53 but not to mutant p53, and it can interfere with p53 specific DNA binding. RBQ-1 may be a truncated human form of the P2P-R protein.