Difference between revisions of "Part:BBa K4235000"

Revision as of 01:57, 15 September 2022

Human Protein S Gene (PROS1)
Codon optimized for sf9 cells

Usage and Biology

Protein S is a vitamin K-dependent plasma protein that functions to prevent hypercoagulation of the blood. It serves as a non enzymatic cofactor for activated Protein C and is involved in the inactivation of coagulation factors Va and VIIIa. Protein S exists in two states in plasma, about 40% circulates as a free, functionally active form and the remaining 60% exists in the inactive form bound with C4b-binding protein. Protein S is secreted by hepatocytes, megakaryocytes, endothelial cells, etc. The initial form of secreted protein S is a 676 amino acid precursor protein, which undergoes a cleavage of a signal peptide present at the N-terminal, resulting in the mature 635 amino acid protein. Functionally active Protein S can directly bind to inhibit factor IXa, which activates factor X to Xa. Factor Xa and Va together form the prothrombinase complex responsible for activation of thrombin. Moreover, by acting as a cofactor for activated protein C, protein S promotes the cleavage of Factor VIIIa and Va, inhibiting the coagulation cascades.

Mutations in this gene (inherited as an autosomal dominant, homozygous or heterozygous fashion) cause non-functional or lower plasma levels of Protein S resulting in a Protein S deficiency. Individuals with Protein S deficiency are at an increased risk of developing abnormal blood clots, specifically in the smaller veins, known as venous thromboembolism. Two most common conditions associated with Protein S deficiency are deep vein thrombosis and pulmonary embolism. Although rare, infants with severe protein S deficiency can develop several blood clots throughout the body, resulting in a life threatening condition known as purpura fulminans. Moreover, severe COVID-19 infections are known to cause a decline in protein S levels, which further contributes to infection severity by causing extensive endothelial dysfunction and lung damage, which is a major cause of COVID-related mortality.

Sequence and Features

Protein Modeling

Future Direction