THROMBIN ACTIVATION OF HUMAN PLATELETS CAUSES TYROSINE PHOSPHORYLATION OF PLC-GAMMA(2)

Citation
Bf. Tate et Se. Rittenhouse, THROMBIN ACTIVATION OF HUMAN PLATELETS CAUSES TYROSINE PHOSPHORYLATION OF PLC-GAMMA(2), Biochimica et biophysica acta, 1178(3), 1993, pp. 281-285
Citations number
30
Categorie Soggetti
Biophysics,Biology
ISSN journal
00063002
Volume
1178
Issue
3
Year of publication
1993
Pages
281 - 285
Database
ISI
SICI code
0006-3002(1993)1178:3<281:TAOHPC>2.0.ZU;2-S
Abstract
Human platelets contain phospholipase C (PLC)-gamma2, a distinct isofo rm closely related to PLC-gamma1. Both inositol phospholipid-specific phospholipases C contain the src-related SH2 regions. Stimulation of p latelets with the potent agonist, thrombin, led to a rapid and transie nt phosphorylation of PLC-gamma2 on tyrosine residues. Activated plate lets lysed in the absence of sodium orthovanadate had levels of tyrosi ne-phosphorylated PLC-gamma2 paralleling those seen in unstimulated pl atelets. Previously, it had been shown that PLC-gamma1 was phosphoryla ted on tyrosine residues by the agonist-occupied platelet-derived grow th factor (PDGF) receptor and epidermal growth factor (EGF) receptor i n cells other than platelets. In addition, more recent data have indic ated that PLC-gamma2 is also capable of being tyrosine-phosphorylated in cells of hematopoietic origin, such as B cells and natural killer ( NK) cells. Here we report that PLC-gamma2 expressed in a terminally-di fferentiated hematopoietic cell is also tyrosine-phosphorylated in res ponse to an agonist.