Linked Life Data

9192762

Source:http://linkedlifedata.com/resource/pubmed/id/9192762

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
12
pubmed:dateCreated
1997-7-10
pubmed:abstractText
Tyrosine phosphorylation of a number of platelet proteins is dependent on platelet integrin alphaIIb beta3 (also termed GPIIb-IIIa) and its engagement in aggregation. For instance, in type I thrombasthenic platelets, which lack alphaIIb beta3 and do not aggregate, several substrates are either poorly or not phosphorylated. We have compared thrombasthenic platelets of type I, type II (15% alphaIIb beta3, functional), and variant type (50% alphaIIb beta3, no fibrinogen binding). The platelets from the three patients exhibited the same low tyrosine phosphorylation profiles, confirming the key role of functional alphaIIb beta3 in initiating protein tyrosine phosphorylation. We noted that in addition to the characteristic absence of the 100 to 105 kD doublet, a 77 to 80 kD doublet and to a lesser extent a 64-kD band, exhibited low phosphorylation kinetics, but with normal initial phosphorylation rates (up to 60 seconds). Similar results were obtained by inhibition of thrombin aggregation of control platelets by alphaIIb beta3 antagonists (the RGDS peptide or the monoclonal antibody 10E5), or in the absence of stirring (fibrinogen binding, but no aggregation). These results suggest that tyrosine phosphorylation of the 77 to 80 kD doublet, identified by immunoprecipitation as the cytoskeletal protein cortactin, and the 64 kD band are dependent both on thrombin activation during early steps and on the late steps of alphaIIb beta3 engagement in aggregation. Implications as to involvement of step-specific kinase and/or phosphatase activities are discussed.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0006-4971
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
89
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4385-92
pubmed:dateRevised
2005-11-17
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Reassessment of protein tyrosine phosphorylation in thrombasthenic platelets: evidence that phosphorylation of cortactin and a 64-kD protein is dependent on thrombin activation and integrin alphaIIb beta3.
pubmed:affiliation
INSERM Unité 348, IFR Circulation-Lariboisière and IVS, Hôpital Lariboisière, Paris, France.
pubmed:publicationType
Journal Article