Fibrinogen alpha chain

Homo sapiensTaxon: 9606

3D-structureAdaptive immunityAlternative splicingAmyloidAmyloidosisBlood coagulationCalciumCoiled coilDirect protein sequencingDisease variantDisulfide bondGlycoprotein+11

序列长度

866

氨基酸

分子量

95.0 kDa

理论值

实验结构

PDB 条目

功能描述

Cleaved by the protease thrombin to yield monomers which, together with fibrinogen beta (FGB) and fibrinogen gamma (FGG), polymerize to form an insoluble fibrin matrix. Fibrin has a major function in hemostasis as one of the primary components of blood clots. In addition, functions during the early stages of wound repair to stabilize the lesion and guide cell migration during re-epithelialization. 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. Enhances expression of SELP in activated platelets via an ITGB3-dependent pathway. Maternal fibrinogen is essential for successful pregnancy. Fibrin deposition is also associated with infection, where it protects against IFNG-mediated hemorrhage. May also facilitate the immune response via both innate and T-cell mediated pathways

定位与分布

组织特异性

Detected in blood plasma (at protein level)

相关疾病

Congenital afibrinogenemia

Rare autosomal recessive disorder is characterized by bleeding that varies from mild to severe and by complete absence or extremely low levels of plasma and platelet fibrinogen.

Amyloidosis, hereditary systemic 2

A form of hereditary systemic amyloidosis, a disorder characterized by amyloid deposition in multiple tissues resulting in a wide clinical spectrum. AMYLD2 is an autosomal dominant form characterized by deposition of amyloid preferentially in the glomeruli of the kidney. It clinically presents with hypertension, proteinuria, and finally azotemia. Involvement of liver and spleen may be seen in advanced cases, but heavy glomerular deposition without significant medium sized vessel involvement is characteristic of the disease.

Dysfibrinogenemia, congenital

A disorder characterized by qualitative abnormalities (dysfibrinogenemia) of the circulating fibrinogen. Affected individuals are frequently asymptomatic, but some patients have bleeding diathesis, thromboembolic complications, or both. In some cases, dysfibrinogenemia is associated with low circulating fibrinogen levels (hypodysfibrinogenemia).

氨基酸序列

MFSMRIVCLVLSVVGTAWTADSGEGDFLAEGGGVRGPRVVERHQSACKDSDWPFCSDEDW
NYKCPSGCRMKGLIDEVNQDFTNRINKLKNSLFEYQKNNKDSHSLTTNIMEILRGDFSSA
NNRDNTYNRVSEDLRSRIEVLKRKVIEKVQHIQLLQKNVRAQLVDMKRLEVDIDIKIRSC
RGSCSRALAREVDLKDYEDQQKQLEQVIAKDLLPSRDRQHLPLIKMKPVPDLVPGNFKSQ

FASTA 格式 · 866 个氨基酸 · 分子量 95.0 kDa

实验结构

39 PDB 条目

1BBR1DM41FPH1FZA1FZB1FZC1FZD1FZE1FZF1FZG1LT91LTJ1N861N8E1RE31RE41RF01RF11YCP2A452FFD2H432HLO2HOD2HPC2OYH2OYI2Q9I2XNX2XNY2Z4E3AT03BVH3E1I3GHG3H323HUS4F275CFA

翻译后修饰

•The alpha chain is normally not N-glycosylated (PubMed:23151259), even though glycosylation at Asn-686 was observed when a fragment of the protein was expressed in insect cells (PubMed:9689040). It is well known that heterologous expression of isolated domains can lead to adventitious protein modifications. Besides, glycosylation at Asn-686 is supported by large-scale glycoproteomics studies (PubMed:16335952, PubMed:19159218), but the evidence is still quite tenuous. Most likely, Asn-686 is not glycosylated in the healthy human body, or only with low efficiency
•O-glycosylated
•Forms F13A-mediated cross-links between a glutamine and the epsilon-amino group of a lysine residue, forming fibronectin-fibrinogen heteropolymers
•About one-third of the alpha chains in the molecules in blood were found to be phosphorylated
•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
•Phosphorylated by FAM20C in the extracellular medium