CD141tyypit

CD141tyypit, also known as thrombomodulin, is a cell surface glycoprotein that plays a crucial role in the coagulation cascade. It is a type I transmembrane protein and is expressed on the surface of endothelial cells, monocytes, and macrophages. Thrombomodulin is composed of an extracellular domain, a transmembrane domain, and a short intracellular tail.

The extracellular domain of thrombomodulin contains several functional regions, including a lectin-like domain, an epidermal growth factor (EGF)-like domain, and a thrombin-binding domain. The primary function of thrombomodulin is to bind thrombin, a key enzyme in the coagulation cascade. By binding to thrombin, thrombomodulin significantly alters thrombin's substrate specificity, converting it from a procoagulant enzyme to an anticoagulant one.

This anticoagulant function is mediated by thrombomodulin's interaction with another protein called Protein C. When thrombomodulin binds thrombin, it facilitates the activation of Protein C. Activated Protein C, in conjunction with its cofactor Protein S, then inactivates factors Va and VIIIa, which are essential for thrombin generation. This regulatory mechanism helps to prevent excessive clot formation and maintain hemostasis.

Besides its role in coagulation, thrombomodulin is also involved in other cellular processes, including inflammation, apoptosis, and cell adhesion. It has been implicated in various pathological conditions, such as sepsis, disseminated intravascular coagulation (DIC), and atherosclerosis. Studies suggest that thrombomodulin may also have therapeutic potential in treating thrombotic disorders.