p18INK4c

p18INK4c, also known as CDKN2C, is a protein encoded by the CDKN2C gene. It belongs to the INK4 family of cyclin-dependent kinase inhibitors. These inhibitors play a critical role in regulating the cell cycle, specifically by preventing the activation of cyclin-dependent kinases (CDKs) that are responsible for driving the cell through its different phases.

The p18INK4c protein primarily targets CDK4 and CDK6. By binding to these CDKs, p18INK4c inhibits their association with D-type cyclins, which are necessary for the transition from the G1 phase to the S phase of the cell cycle. This inhibition effectively acts as a brake on cell proliferation, preventing uncontrolled cell division.

The expression of p18INK4c is tightly regulated and can be influenced by various cellular signals. Its role as a tumor suppressor has been investigated, as its loss or dysregulation can contribute to the development of various cancers. For instance, it is often found to be downregulated or absent in certain types of lymphomas and leukemias. Studies have also linked p18INK4c to cellular differentiation and the maintenance of stem cell populations. Its precise mechanisms of action and its involvement in different biological processes are still areas of active research.