mouse monoclonal IgG2b; p21 Waf1/Cip1 Antibody (F-5) is an IgG2b κ mouse monoclonal p21 Waf1/Cip1 antibody (also designated CIP1 antibody, WAF1 antibody, CDKN1A antibody or p21 antibody) that detects the p21 Waf1/Cip1 protein of mouse, rat and human origin by WB, IP, IF, IHC(P) and FCM. p21 Waf1/Cip1 Antibody (F-5) is available as both the non-conjugated anti-p21 Waf1/Cip1 antibody form, as well as multiple conjugated forms of anti-p21 Waf1/Cip1 antibody, including agarose, HRP, PE, FITC and multiple Alexa Fluor® conjugates. It is now well established that cyclins play a positive role in promoting cell cycle transitions via their ability to associate with and activate their cognate cyclin-dependent kinases (Cdks). Cdk2 associates with cyclins A, D and E, and has been implicated in the control of the G1 to S phase transition in mammals. p21 Waf1/Cip1, also designated Cip1 or WAF1, has been identified in cyclin A, cyclin D1, cyclin E and Cdk2 immunoprecipitates. The novel Cdk-interacting protein, p21 Waf1/Cip1 is a potent, tight-binding inhibitor of Cdks and can inhibit the phosphorylation of Rb by cyclin A-Cdk 2, cyclin E-Cdk2, cyclin D1-Cdk4 and cyclin D2-Cdk4 complexes. Expression of p21 Waf1/Cip1 protein, which is identified using the p21 Waf1/Cip1 Antibody (F-5) in various research applications, is inducible by wildtype, but not mutant, p53. The mouse homolog of p21 Waf1/Cip1 is designated CAP20.