scholarly journals Production and functional activity of a recombinant von Willebrand factor-A domain from human complement factor B

1999 ◽  
Vol 342 (3) ◽  
pp. 625-632 ◽  
Author(s):  
Samantha C. WILLIAMS ◽  
Justin HINSHELWOOD ◽  
Stephen J. PERKINS ◽  
Robert B. SIM
Keyword(s):  
Fusion Protein ◽  
Von Willebrand Factor ◽  
Analytical Ultracentrifugation ◽  
Expression System ◽  
High Yield ◽  
Binding Property ◽  
Complement Factor ◽  
Factor B ◽  
Von Willebrand ◽  
Willebrand Factor

Factor B is a five-domain 90 kDa serine protease proenzyme which is part of the human serum complement system. It binds to other complement proteins C3b and properdin, and is activated by the protease factor D. The fourth domain of factor B is homologous to the type A domain of von Willebrand Factor (vWF-A). A full-length human factor B cDNA clone was used to amplify the region encoding the vWF-A domain (amino acids 229-444 of factor B). A fusion protein expression system was then used to generate it in high yield in Escherichia coli, where thrombin cleavage was used to separate the vWF-A domain from its fusion protein partner. A second vWF-A domain with improved stability and solubility was created using a Cys267 → Ser mutation and a four-residue C-terminal extension of the first vWF-A domain. The recombinant domains were investigated by analytical gel filtration, sucrose density centrifugation and analytical ultracentrifugation, in order to show that both domains were monomeric and possessed compact structures that were consistent with known vWF-A crystal structures. This expression system and its characterization permitted the first investigation of the function of the isolated vWF-A domain. It was able to inhibit substantially the binding of 125I-labelled factor B to immobilized C3b. This demonstrated both the presence of a C3b binding site in this portion of factor B and a ligand-binding property of the vWF-A domain. The site at which factor D cleaves factor B is close to the N-terminus of both recombinant vWF-A domains. Factor D was shown to cleave the vWF-A domain in the presence or absence of C3b, whereas the cleavage of intact factor B under the same conditions occurs only in the presence of C3b.

Surface Loops Adjacent to the Cation-Binding Site of the Complement Factor B von Willebrand Factor Type A Module Determine C3b Binding Specificity†

Biochemistry ◽  
1997 ◽  
Vol 36 (22) ◽  
pp. 6605-6613 ◽  
Author(s):  
Danny S. Tuckwell ◽  
Yuanyuan Xu ◽  
Peter Newham ◽  
Martin J. Humphries ◽  
John E. Volanakis
Keyword(s):  
Binding Site ◽  
Von Willebrand Factor ◽  
Cation Binding ◽  
Complement Factor ◽  
Factor B ◽  
Cation Binding Site ◽  
Factor Type ◽  
Surface Loops ◽  
Von Willebrand ◽  
Willebrand Factor

VON WILLEBRAND FACTOR (vWF) PRO-POLYPEPTIDE IS REQUIRED FOR vWF MULTIMER FORMATION

1987 ◽  
Author(s):  
C L Verweij ◽  
M Hart ◽  
H Pannekoek
Keyword(s):  
Endothelial Cells ◽  
Von Willebrand Factor ◽  
Secretory Pathway ◽  
Vascular Endothelial Cells ◽  
Expression System ◽  
Proteolytic Processing ◽  
Information Encoding ◽  
Interchain Interactions ◽  
Von Willebrand ◽  
Willebrand Factor

The von Willebrand factor (vWF) is a multimeric plasma glycoprotein synthesized in vascular endothelial cells as a pre-pro-polypeptide with a highly repetitive domain structure, symbolized by the formula:(H)-D1-D2-D'-D3-A1-A2-A3-D4-B1-B2-B3-C1-C2-(0H).A heterologous expression system, consisting of a monkey kidney cell line (C0S-1), transfected with full-length vWF cDNA, is shown to mimic the constitutively, secretory pathway of vWF in endothelial cells. The assembly of pro-vWF into multimers and the proteolytic processing of these structures is found to oro-ceed along the following, consecutive steps. Pro-vWF subunits associate to form dimers, a process that does not involve the pro-polypeptide of pro-vWF. This observation is derived from transfection of C0S-1 cells with vWF cDNA, lacking the genetic information encoding the pro-polypeptide, composed of the domains D1 and D2. Pro-vWF dimers are linked intracellularly to form a regular series of multimeric structures that are secreted and cannot be distinguished from those released constitutively by endothelial cells. The presence of the pro-polypeptide, embedded in pro-vWF, is obligatory for multimerization since the deletion mutant lacking the D1 and D2 domains fails to assemble beyond the dimer stage. It is argued that the D domains are involved in interchain interactions.

Filamin A binding to the cytoplasmic tail of glycoprotein Ibα regulates von Willebrand factor–induced platelet activation

Blood ◽  
2003 ◽  
Vol 102 (6) ◽  
pp. 2122-2129 ◽  
Author(s):  
Shuju Feng ◽  
Julio C. Reséndiz ◽  
Xin Lu ◽  
Michael H. Kroll
Keyword(s):  
Shear Stress ◽  
Platelet Aggregation ◽  
Fusion Protein ◽  
Platelet Activation ◽  
Von Willebrand Factor ◽  
Cytoplasmic Tail ◽  
Cytoplasmic Domain ◽  
Filamin A ◽  
Von Willebrand ◽  
Willebrand Factor

Abstract We examined the hypothesis that filamin A binding to the cytoplasmic tail of platelet glycoprotein Ibα (GpIbα) is regulated by pathologic shear stress and modulates von Willebrand factor (VWF)–induced platelet activation. To begin, we examined filamin binding to GpIbα in Chinese hamster ovary cells coexpressing mutant human GpIb-IX and wild-type human filamin A. We observed that many different deletions and truncations N-terminal to GpIbα's cytoplasmic domain residue 594 disrupted filamin A binding, but that binding was unaffected by 14 different point mutations in hydrophilic residues between amino acids 557 and 593. To try to narrow GpIbα's filamin A–binding domain, we next measured the effect of several cytoplasmic domain peptides on human filamin A binding to a GST-GpIbα cytoplasmic domain fusion protein. One peptide (residues 557-575; designated “A4 peptide”) inhibited filamin A binding to the GST-GpIbα cytoplasmic domain fusion protein and competed with GpIbα for binding to filamin A. When the A4 peptide was delivered to intact human platelets using a carrier peptide, we observed the dose-dependent inhibition of VWF-induced platelet aggregation in response to both ristocetin and shear stress. The effect of the A4 peptide on shear-induced platelet aggregation was accompanied by the attenuation of shear-induced filamin A binding to GpIbα and diminished shear-dependent protein tyrosine phosphorylation. These results suggest that shear-dependent VWF-induced platelet activation affects filamin A binding to GpIb-IX-V, and that filamin A binding to the cytoplasmic tail of GpIbα regulates proaggregatory tyrosine kinase signaling.

scholarly journals Analysis focusing on plasma von Willebrand factor in pachychoroid neovasculopathy and age-related macular degeneration

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hiromasa Hirai ◽  
Mariko Yamashita ◽  
Masanori Matsumoto ◽  
Masaki Hayakawa ◽  
Kazuya Sakai ◽  
...  
Keyword(s):  
Macular Degeneration ◽  
Von Willebrand Factor ◽  
Factor H ◽  
Age Related Macular Degeneration ◽  
Complement Factor ◽  
Clinical Criteria ◽  
Age Related ◽  
Pachychoroid Neovasculopathy ◽  
Von Willebrand ◽  
Willebrand Factor

AbstractPachychoroid neovasculopathy (PNV) is a new concept of macular disorder. Some cases diagnosed as age-related macular degeneration (AMD) have been re-diagnosed as PNV. However, the biological features of PNV are still uncertain. The purpose of this study was to compare PNV and AMD by analyses focusing on von Willebrand factor (VWF) and complement factor H (CFH). Ninety-seven patients who were previously diagnosed with treatment naïve AMD were enrolled in this study. They were re-classified as either PNV or AMD based on the clinical criteria and 33 patients were classified as PNV and 64 patients as AMD. We examined the clinical data, analyzed VWF multimer and two genetic polymorphisms (I62V and Y402H) in the CFH. PNV group was significantly younger than AMD group (P = 0.001). In both I62V and Y402H, there were no significant differences between PNV and AMD while the recessive homozygous (AA) was found only in PNV group in I62V. The presence of unusually large VWF multimers (UL-VWFMs) and subretinal hemorrhages were significantly higher in PNV than in AMD (P = 0.045, P = 0.020, respectively). Thus, the residual UL-VWFMs may result in platelet thrombosis and hemorrhages in the choriocapillaris of PNV. In conclusion, our results suggest the biological differences between PNV and AMD.

scholarly journals Physicochemical Characteristics of the Human Factor VIII-Von Willebrand Factor Oligomers

1977 ◽  
Author(s):  
P. A. Bolhuis ◽  
A. J. Seinen ◽  
I. A. Mochtar
Keyword(s):  
Factor Viii ◽  
Von Willebrand Factor ◽  
Human Factor ◽  
Analytical Ultracentrifugation ◽  
Double Diffusion ◽  
Physicochemical Characteristics ◽  
Equivalent Amount ◽  
Human Factor Viii ◽  
Von Willebrand ◽  
Willebrand Factor

Analytical ultracentrifugation of the factor VIII-Von Willebrand factor showed an apparently homogenous protein with an S° of 29. With the diffusion coefficient D of 1.24 x 10-7 cm2/ sec.(obtained by 20,w double diffusion of the protein and the immunochemically equivalent amount of rabbit anti-factor VIII) a mean mol. wt. of 2.2 x 106 and a friction ratio of 1.9 are derived. Turbidity measurements confirmed the high mol. wt. and resulted in an estimation of the co-volume of the protein. The free electric mobility wasfound to be 3.6 x 10-5 cm2/Vsec at pd 7.00 and 8.5x 10-5cm2/V sec at pH 8.80, while iso-electric focussing patterns of the native protein and the polypeptide (mol.wt. 260 000) obtained by reduction in the presence of urea exhibited a maximum at about pH 4.5. The apparent D found upon electrophoresis is an order higher than given above and is dependent on the field strength. The heterogeneity indicated by this phenomenon was confirmed by reversal electrophoresis (yielding a decrease in the apparent D). Since continuous immuno precipitation lines are found upon cross-electrophoresis, we interprete the results in terms of a series of closely related oligomers with a mean number of 8 polypeptidechains and a variation from about 6 to 10.

scholarly journals Human Complement Factor H Is a Reductase for Large Soluble von Willebrand Factor Multimers—Brief Report

2013 ◽  
Vol 33 (11) ◽  
pp. 2524-2528 ◽  
Author(s):  
Leticia Nolasco ◽  
Jennifer Nolasco ◽  
Shuju Feng ◽  
Vahid Afshar-Kharghan ◽  
Joel Moake
Keyword(s):  
Von Willebrand Factor ◽  
Factor H ◽  
Complement Factor H ◽  
Complement Factor ◽  
Human Complement ◽  
Von Willebrand ◽  
Willebrand Factor

The interaction between factor H and VWF increases factor H cofactor activity and regulates VWF prothrombotic status

Blood ◽  
2014 ◽  
Vol 123 (1) ◽  
pp. 121-125 ◽  
Author(s):  
Julie Rayes ◽  
Lubka T. Roumenina ◽  
Jordan D. Dimitrov ◽  
Yohann Repessé ◽  
Mathieu Ing ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Platelet Aggregation ◽  
Von Willebrand Factor ◽  
Factor H ◽  
Complement Factor H ◽  
Complement Factor ◽  
Key Points ◽  
Cofactor Activity ◽  
Von Willebrand ◽  
Willebrand Factor

Key Points Complement factor H and von Willebrand factor colocalize in the Weibel-Palade bodies of endothelial cells and interact in normal plasma. Formation of the complex enhances FH cofactor activity and VWF-mediated platelet aggregation.

Sign in / Sign up

Export Citation Format

Share Document