Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2004-12-20
pubmed:abstractText
This study investigated the functional impact of O-linked glycosylation of von Willebrand Factor (VWF) A1 domains on the interaction with platelet receptors. Native or mutant VWF-A1-domains were transiently overexpressed on COS-7 cells as membrane glycosylphosphatidylinositol (GPI)-anchored FLAG-tagged fusion proteins. Cytofluometric analysis assured comparable levels of A1-domain expression among native and mutant homologues as well as for different culture conditions. Expressing native VWF-A1-domains under O-linked glycosylation blocking conditions increased the platelet aggregatory responses observed for fully glycosylated forms. Utilizing a neuronal network for prediction of O-linked glycosylation of mammalian proteins, threonine (T) and serine (S) residues located in the VWF-A1-loop flanking regions - not in the loop itself - were determined to be glycosylated n-terminal at amino acids T485, S490, T492 and T493 and c-terminal at T705. Simultaneous selective charge-to-alanine mutation of S490, T492 and T493 led to gain in aggregatory responses. When compared with native forms, equivalent alterations of T485 did not dictate functional differences. Any alanine-substitution for T705 revealed a substantial loss in aggregatory effects - possibly as a result of structural desintegration of the VWF-A1-binding site for glycoprotein (GP) Ib. These data suggest specific O-linked glycosylation of the amino-terminal VWF-A1-loop-flanking region to have a negative regulatory impact on the A1-domain affinity of non-activated human VWF for human platelet-GPIb.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0007-1048
pubmed:author
pubmed:issnType
Print
pubmed:volume
128
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
82-90
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Impact of O-linked glycosylation of the VWF-A1-domain flanking regions on platelet interaction.
pubmed:affiliation
Clinic for General and Visceral Surgery, Heinrich Heine University Duesseldorf, Germany. jan.schulteamesch@uni-duesseldorf.de
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't