Protein c

Protein C is a vitamin K-dependent serine protease that regulates blood coagulation by inactivating factors Va and VIIIa in the presence of calcium ions and phospholipids. Protein C is encoded by the PROC gene and is produced in the liver.

Structure

Protein C is a two-chain structure: a light chain and a heavy chain, connected by a disulfide bond. The light chain contains two EGF-like domains, while the heavy chain contains the serine protease domain.

Function

The primary function of Protein C is to regulate clotting. It does this by cleaving and inactivating the cofactors Va and VIIIa, slowing down the clotting process. This is a critical function as it prevents thrombosis and promotes fibrinolysis, the breakdown of fibrin clots.

Clinical significance

Deficiency of Protein C can lead to thrombophilia, a rare genetic disorder that results in an increased risk of blood clot formation. This can lead to conditions such as deep vein thrombosis and pulmonary embolism. Protein C deficiency can be inherited or acquired.

See also

• Protein S
• Protein Z
• Blood coagulation