Clone: 1F7

Isotype: IgG2a

Immunogen: Human Fibrinopeptide A conjugated with a carrier protein.

Antigen Species: Human

Specificity: Fibrinopeptide A region in the alpha chain of fibrinogen and free fibrinopeptide A. Target: Fibrinopeptide A

Localization: Secreted

Concentration: 6 mg/ml Storage Buffer: Phosphate-buffered saline, pH 7.4, containing 0.1% sodium azide

Application Note: ELISA: As a capture antibody in a sandwich assay with an appropriate detection antibody. Use at an assay dependent dilution. Not tested in other applications. Optimal dilutions/concentrations should be determined by the end user.

Cellular Localization: Secreted

Myeloma: Sp2/0 Fibrinogen is the main protein of the blood coagulation system. It is a large protein and it consists of two identical subunits that contain three polypeptide chains: alpha, beta and gamma. All chains are connected with each other by a number of disulfide bonds. Fibrinopeptides A and B are released by thrombin from the N terminal parts of alpha and beta chains, respectively. In this way fibrinogen is converted into fibrin, which by means of polymerisation forms a fibrin clot. Fibrinogen clotting underlies pathogenesis of MI, thromboembolism and thromboses of arteries and veins, since fibrin is the main substrate for thrombus formation. Fibrinogen activation is also involved in pathogenesis of inflammation, tumor growth and many other diseases.

Function: Fibrinogen has a double function: yielding monomers that polymerize into fibrin and acting as a cofactor in platelet aggregation.

Subunit: Heterohexamer; disulfide linked. Contains 2 sets of 3 non-identical chains (alpha, beta and gamma). The 2 heterotrimers are in head to head conformation with the N-termini in a small central domain.

Subcellular Location: Secreted.

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.

Ptm: The alpha chain is not glycosylated.

Ptm: Forms F13A-mediated cross-links between a glutamine and the epsilon-amino group of a lysine residue, forming fibronectin-fibrinogen heteropolymers.

Ptm: About one-third of the alpha chains in the molecules in blood were found to be phosphorylated.

Ptm: 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.

Disease: Defects in FGA are a cause of congenital afibrinogenemia [MIM:202400]. This is a rare autosomal recessive disorder characterized by bleeding that varies from mild to severe and by complete absence or extremely low levels of plasma and platelet fibrinogen. The majority of cases of afibrinogenemia are due to truncating mutations.

Disease: Variations in position Arg-35 (the site of cleavage of fibrinopeptide a by thrombin) leads to alpha-dysfibrinogenemias.

Disease: Defects in FGA are a cause of amyloidois type 8 (AMYL8) [MIM:105200]; also known as systemic non-neuropathic amyloidosis or Ostertag-type amyloidosis. AMYL8 is a hereditary generalized amyloidosis due to deposition of apolipoprotein A1, fibrinogen and lysozyme amyloids. Viscera are particularly affected. There is no involvement of the nervous system. Clinical features include renal amyloidosis resulting in nephrotic syndrome, arterial hypertension, hepatosplenomegaly, cholestasis, petechial skin rash.

Similarity: Contains 1 fibrinogen C-terminal domain.