Von Willebrand Factor (VWF) was previously known as Factor VIII related antigen. VWF is synthesized exclusively by endothelial cells and megakaryocytes, and stored in the intracellular granules or constitutively secreted into plasma. This glycoprotein functions as both an antihemophilic factor carrier and a platelet vessel wall mediator in the blood coagulation system. Important in the maintenance of homeostasis, it participates in platelet vessel wall interactions by forming a noncovalent complex with coagulation factor VIII at the site of vascular injury. The Von Willebrand factor has functional binding domains to platelet glycoprotein Ib, glycoprotein IIb/IIIa, collagen and heparin. Mutations in this gene or deficiencies in this protein result in Von Willebrand's disease. VWD is characterized by frequent bleeding (gingival, minor skin quantitative lacerations, menorrhagia, etc.).
Function:
Important in the maintenance of hemostasis, it promotes adhesion of platelets to the sites of vascular injury by forming a molecular bridge between sub-endothelial collagen matrix and platelet-surface receptor complex GPIb-IX-V. Also acts as a chaperone for coagulation factor VIII, delivering it to the site of injury, stabilizing its heterodimeric structure and protecting it from premature clearance from plasma.
Subunit : Multimeric. Interacts with F8.
Subcellular Location:
Secreted. Secreted, extracellular space, extracellular matrix. Note=Localized to storage granules.
Tissue Specificity:
Plasma.
Post-translational modifications:
All cysteine residues are involved in intrachain or interchain disulfide bonds.
N- and O-glycosylated.
DISEASE:
Defects in VWF are the cause of von Willebrand disease type 1 (VWD1) [MIM:193400]. A common hemorrhagic disorder due to defects in von Willebrand factor protein and resulting in impaired platelet aggregation. Von Willebrand disease type 1 is characterized by partial quantitative deficiency of circulating von Willebrand factor, that is otherwise structurally and functionally normal. Clinical manifestations are mucocutaneous bleeding, such as epistaxis and menorrhagia, and prolonged bleeding after surgery or trauma.
Defects in VWF are the cause of von Willebrand disease type 2 (VWD2) [MIM:613554]. A hemorrhagic disorder due to defects in von Willebrand factor protein and resulting in impaired platelet aggregation. Von Willebrand disease type 2 is characterized by qualitative deficiency and functional anomalies of von Willebrand factor. It is divided in different subtypes including 2A, 2B, 2M and 2N (Normandy variant). The mutant VWF protein in types 2A, 2B and 2M are defective in their platelet-dependent function, whereas the mutant protein in type 2N is defective in its ability to bind factor VIII. Clinical manifestations are mucocutaneous bleeding, such as epistaxis and menorrhagia, and prolonged bleeding after surgery or trauma.
Defects in VWF are the cause of von Willebrand disease type 3 (VWD3) [MIM:27796]. A severe hemorrhagic disorder due to a total or near total absence of von Willebrand factor in the plasma and cellular compartments, also leading to a profound deficiency of plasmatic factor VIII. Bleeding usually starts in infancy and can include epistaxis, recurrent mucocutaneous bleeding, excessive bleeding after minor trauma, and hemarthroses.
Similarity:
Contains 1 CTCK (SLCterminal cystine knot-like) domain.
Contains 4 TIL (trypsin inhibitory-like) domains.
Contains 3 VWFA domains.
SWISS:
P04275
Gene ID:
7450
Database links:
Entrez Gene: 280958 Cow
Entrez Gene: 399544 Dog
Entrez Gene: 7450 Human
Entrez Gene: 399543 Pig
Entrez Gene: 116669 Rat
Omim: 613160 Human
SwissProt: Q28295 Dog
SwissProt: P04275 Human
SwissProt: Q28833 Pig
SwissProt: Q62935 Rat
Unigene: 88848 Human
Unigene: 35561 Rat
血管性血友病因子(vWF)是血管内皮细胞和骨髓巨核细胞合成的一种糖蛋白,在1期和2期止血中都起着重要作用,如缺乏将导致患者出现血管性血友病(vWD)。vWF可被ADAMTS13裂解以失去活性,血小板反应蛋白/凝血酶敏感蛋白-1(Thrombospondin,TSP-1))可参与了这个调节过程。vWF水平受多种遗传和环境因素影响,其中ABO血型影响较大。vWF主要通过A1和A3区与血小板GP 1b和胶原结合,在止血和血栓形成过程中起重要作用,并与心、脑血管疾病及血管新生密切相关,因此研究vWF的生物学特性和功能具有重要的意义。
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