Cyclin-dependent kinase 4

Cyclin-dependent kinase 4 also known as cell division protein kinase 4 is an is_associated_with::enzyme that in humans is encoded by the CDK4 is_associated_with::gene. CDK4 is a member of the is_associated_with::cyclin-dependent kinase family.

Function
The protein encoded by this gene is a member of the Ser/Thr protein kinase family. This protein is highly similar to the gene products of is_associated_with::S. cerevisiae cdc28 and is_associated_with::S. pombe cdc2. It is a catalytic subunit of the protein kinase complex that is important for is_associated_with::cell cycle G1 phase progression. The activity of this kinase is restricted to the G1-S phase, which is controlled by the regulatory subunits D-type cyclins and CDK inhibitor p16INK4a. This kinase was shown to be responsible for the phosphorylation of is_associated_with::retinoblastoma gene product (Rb).

Clinical significance
Mutations in this gene as well as in its related proteins including D-type cyclins, p16(INK4a) and Rb were all found to be associated with tumorigenesis of a variety of cancers. Multiple polyadenylation sites of this gene have been reported.

It is regulated by is_associated_with::Cyclin D.

Interactions
Cyclin-dependent kinase 4 has been shown to interact with:


 * is_associated_with::CDC37,
 * is_associated_with::CDKN1B,
 * is_associated_with::CDKN2B,
 * is_associated_with::CDKN2C,
 * is_associated_with::CEBPA,
 * CCND1,
 * CCND3,
 * DBNL,
 * is_associated_with::MyoD,
 * P16,
 * is_associated_with::PCNA,  and
 * is_associated_with::SERTAD1.