P16-INK-4A HUMAN

General description

p16-INK4a, which is also known as cyclin dependent kinase inhibitor 2A (CDKN2A), is a nuclear protein. The gene encoding this protein is localized on human chromosome 9p21, with three exons. Recombinant p16-INK4a is a 16.5kDa protein containing 156 amino acid residues.

Biochem/physiol Actions

Cyclin dependent kinase inhibitor 2A (CDKN2A) or p16-INK4a regulates the cell cycle by inhibiting cyclin dependent kinase-4 (CDK4) and CDK6. It inhibits CDK activity by binding to the CDK molecules in a manner that interferes with their ability to interact with cyclin D. This activity has the effect of suppressing tumor formation and growth, and of inducing replicative senescence in various normal cells, including stem cells. The expression of p16-INK4a steadily increases with age and tends to accumulate in stem cell compartments. The deletion, rearrangement, or mutation of the p16-INK4a gene is frequently found in melanomas as well as in certain other types of cancer. The protein is downregulated in bladder cancer.

Sequence

MEPAAGSSME PSADWLATAA ARGRVEEVRA LLEAGALPNA PNSYGRRPIQ VMMMGSARVA ELLLLHGAEP NCADPATLTR PVHDAAREGF LDTLVVLHRA GARLDVRDAW GRLPVDLAEE LGHRDVARYL RAAAGGTRGS NHARIDAAEG PSDIPD

Physical form

Lyophilized from 1 x PBS + 1.0 mM DTT, pH 7.2.

Reconstitution

Centrifuge the vial prior to opening. Reconstitute in water to a concentration of 0.1-1.0 mg/ml. Do not vortex. This solution can be stored at 2-8°C for up to 1 week. For extended storage, it is recommended to further dilute in a buffer containing a carrier protein (example 0.1% BSA) and store in working aliquots at -20°C to -80°C.