Cyclin-dependent kinase inhibitors (CDKIs) are proteins that bind to and inhibit the activity of CDKs. Two major classes of CDK inhibitors have been identified. The p16 family (p15, p16, p18 and p19) binds to and inhibits the activities of CDK4 and CDK6. The p21 family (p21, p27, p28 and p57) can bind to broad range of CDK-cyclin complexes and inhibit their activities. CDKIs are capable of suppressing growth, and several lines of evidence strongly suggest that at least some CDKIs may be tumor suppressor proteins.
p16-INK4a Human Recombinant is a single, non-glycosylated, polypeptide chain produced in E.coli, containing a total of 168 amino acids, which includes the 156 residues of full-length p16-INK4a and a 13-residue C-terminal TAT peptide (GGYGRKKRRQRRR), having a total Mw of 18kDa. p16-INK4a is purified by proprietary chromatographic techniques.