Linked Life Data

11943773

Source:http://linkedlifedata.com/resource/pubmed/id/11943773

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
24
pubmed:dateCreated
2002-6-10
pubmed:abstractText
In vitro platelet glycoprotein Ib (GPIb) binding of the human von Willebrand factor (VWF) increases markedly by exogenous modulators such as ristocetin or botrocetin, and the binding does not occur in normal circulation. GPIb binding sites have been assigned in the VWF A1 domain, which consists of a disulfide loop Cys1272(509)-Cys1458(695) where amino acid residues are numbered from the starting methionine as +1. The previous numbering from the N-terminal Ser of the mature processed VWF is indicated in parentheses. In contrast, several gain-of-function mutations have been found in two regions comprised of the disulfide loop and its N- and C-terminal flanking regions. In this study, Cys1222(459)-Tyr1271(508), Gln1238(475)-Tyr1271(508), Glu1260(497)-Tyr1271(508), and Asp1459(696)-Asp1472(709) were sequentially deleted of full-length multimeric recombinant VWF. Deletions at either side resulted in normal GPIb binding, indicating that the flanking regions are not GPIb binding sites. However, the addition of a mutation at Arg1308(545) on each deletion mutant resulted in spontaneous GPIb binding without requiring modulators, suggesting that both regions are important for the inhibition of GPIb binding. Spontaneous binding was completely inhibited by monoclonal antibodies that recognize the GPIb binding sites. Interestingly, mutant proteins with N-terminal but not C-terminal deletions lost binding to monoclonal antibodies B328, B710, and 23C7, which selectively inhibit ristocetin-induced GPI binding. Their epitopes were found at His1268(505) or Asp1269(506). The crystallographic structure of the A1 domain suggests that GPIb binding is influenced by the molecular interface between the two regions and that the antibody binding to the interface inhibits binding.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
14
pubmed:volume
277
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
22063-72
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:11943773-Anti-Bacterial Agents, pubmed-meshheading:11943773-Binding Sites, pubmed-meshheading:11943773-Biotinylation, pubmed-meshheading:11943773-Blood Platelets, pubmed-meshheading:11943773-Cell Line, pubmed-meshheading:11943773-Crotalid Venoms, pubmed-meshheading:11943773-Cysteine, pubmed-meshheading:11943773-Dimerization, pubmed-meshheading:11943773-Disulfides, pubmed-meshheading:11943773-Dose-Response Relationship, Drug, pubmed-meshheading:11943773-Epitope Mapping, pubmed-meshheading:11943773-Gene Deletion, pubmed-meshheading:11943773-Humans, pubmed-meshheading:11943773-Immunoglobulin G, pubmed-meshheading:11943773-Models, Molecular, pubmed-meshheading:11943773-Plasmids, pubmed-meshheading:11943773-Platelet Glycoprotein GPIb-IX Complex, pubmed-meshheading:11943773-Protein Binding, pubmed-meshheading:11943773-Protein Conformation, pubmed-meshheading:11943773-Protein Structure, Tertiary, pubmed-meshheading:11943773-Recombinant Proteins, pubmed-meshheading:11943773-Ristocetin, pubmed-meshheading:11943773-Tyrosine, pubmed-meshheading:11943773-von Willebrand Factor
pubmed:year
2002
pubmed:articleTitle
Identification of the regulatory elements of the human von Willebrand factor for binding to platelet GPIb. Importance of structural integrity of the regions flanked by the CYS1272-CYS1458 disulfide bond.
pubmed:affiliation
First Department of Internal Medicine, Nagoya University School of Medicine, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't