CDK gene family

The genes in the CDK family provide instructions for making proteins called cyclin-dependent kinases (CDKs). These proteins are best known for their role in regulating the step-by-step process that cells go through to replicate themselves (known as the cell cycle). Tight regulation of the cell cycle ensures that a dividing cell's DNA is copied properly, any errors in the DNA are repaired, and each cell that is produced receives a full set of chromosomes.

CDK proteins act as kinases, which are enzymes that change the activity of other proteins by adding a cluster of oxygen and phosphorus atoms (a phosphate group) at specific positions. Through this process, called phosphorylation, CDKs turn on (activate) or off (inactivate) proteins involved in the different steps of the cell cycle. Unlike some kinases, however, CDKs require interaction with other proteins known as cyclins in order to have kinase activity. Particular CDK and cyclin combinations are involved in each step of the cell cycle.

Many CDK proteins are not directly involved in cell cycle control. Through phosphorylation, these CDKs can regulate other important cellular processes such as the first step in the production of proteins from genes (gene transcription), the maturation of cells to carry out specific functions (differentiation), and the self-destruction of cells (apoptosis).

Some genes in the CDK family are designated cyclin-dependent kinase-like (CDKL). The proteins produced from these genes function as kinases, but they may not require interaction with cyclins to be active. Because these CDK-like proteins have similar functions to other CDK proteins, the genes that provide instructions for them are included in the CDK family.

Some genes in the CDK family produce proteins that are involved in the development and function of cells in the nervous system. Mutations in these genes can disrupt the nervous system, causing neurological problems such as seizures and intellectual disability. Mutations in at least one CDK gene, CDKL5, are associated with disorders that feature recurrent seizures known as infantile spasms, intellectual disability, and other developmental problems.