glycoprotein IIIa

biochemistry

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Last updated

June 29, 2026

Quick Summary

Glycoprotein IIIa is a protein found on the surface of platelets that plays a crucial role in blood clotting. It forms a complex with glycoprotein IIb, and this complex acts as a receptor for fibrinogen. When platelets are activated, this glycoprotein complex binds to fibrinogen, linking platelets together and forming a platelet plug. This process is essential for hemostasis, the stopping of bleeding. Integrins, a broader class of cell surface glycoproteins that include glycoprotein IIIa, are involved in cell adhesion and various biological processes such as wound healing.12

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bleeding and blood clotting
Platelets and their aggregation
…platelet aggregation: glycoprotein IIb and glycoprotein IIIa. These proteins form a complex in the membrane and expose a receptor site after platelet activation that binds fibrinogen (a bivalent molecule with two symmetrical halves that is found in relatively high concentration in plasma). Fibrinogen can bind simultaneously to two platelets. Thus,…
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…platelet aggregation: glycoprotein IIb and glycoprotein IIIa. These proteins form a complex in the membrane and expose a receptor site after platelet activation that binds fibrinogen (a bivalent molecule with two symmetrical halves that is found in relatively high concentration in plasma). Fibrinogen can bind simultaneously to two platelets. Thus,…
Read More