Fibrinogen gamma chain

Domain

A long coiled coil structure formed by 3 polypeptide chains connects the central nodule to the C-terminal domains (distal nodules). The long C-terminal ends of the alpha chains fold back, contributing a fourth strand to the coiled coil structure.

Function

Together with fibrinogen alpha (FGA) and fibrinogen beta (FGB), polymerizes to form an insoluble fibrin matrix (By similarity). Fibrin has a major function in hemostasis as one of the primary components of blood clots (By similarity). In addition, functions during the early stages of wound repair to stabilize the lesion and guide cell migration during re-epithelialization (By similarity). Was originally thought to be essential for platelet aggregation, based on in vitro studies using anticoagulated blood. However, subsequent studies have shown that it is not absolutely required for thrombus formation in vivo (By similarity). Enhances expression of SELP in activated platelets via an ITGB3-dependent pathway (PubMed:19332769). Maternal fibrinogen is essential for successful pregnancy (By similarity). Fibrin deposition is also associated with infection, where it protects against IFNG-mediated hemorrhage (By similarity). May also facilitate the immune response via both innate and T-cell mediated pathways (By similarity).

Post-translational modifications

Conversion of fibrinogen to fibrin is triggered by thrombin, which cleaves fibrinopeptides A and B from alpha and beta chains, and thus exposes the N-terminal polymerization sites responsible for the formation of the soft clot. The soft clot is converted into the hard clot by factor XIIIA which catalyzes the epsilon-(gamma-glutamyl)lysine cross-linking between gamma chains (stronger) and between alpha chains (weaker) of different monomers (By similarity).

Cellular localization

• Secreted

Alternative names

Fibrinogen gamma chain, Fgg

Database links

swissprot:Q8VCM7 entrezGene:14161 entrezGene:110135 swissprot:Q8K0E8 entrezGene:99571