Which vitamin is crucial for the synthesis of clotting factors II, VII, IX, and X?

Vitamin K plays an essential role in the synthesis of clotting factors II (prothrombin), VII, IX, and X, which are critical for the blood coagulation process. These factors are referred to as vitamin K-dependent proteins, and their production occurs in the liver. Vitamin K acts as a cofactor for the enzyme gamma-glutamyl carboxylase, which catalyzes the carboxylation of specific glutamic acid residues on these clotting factors, enabling them to bind calcium ions. This calcium-dependent binding is necessary for the effective functioning of these factors in the coagulation cascade.

Deficiency in vitamin K can lead to decreased synthesis of these clotting factors, resulting in increased bleeding risk and coagulopathy. This is particularly important in clinical settings, where monitoring vitamin K levels and understanding its role in coagulation is crucial for managing patients, especially those on anticoagulant therapies or those with liver disease.