Falet H, Rendu F
INSERM CJF 91-01, Université René Descartes, Paris, France.
FEBS Lett. 1994 May 23;345(1):87-91. doi: 10.1016/0014-5793(94)00414-5.
We have investigated the regulation of tyrosine proteins phosphorylation by intracellular Ca2+ level ([Ca2+]i) and protein kinase C (PKC) during platelet stimulation. We found that chelation of extracellular calcium completely prevented phosphorylation of tyrosine proteins induced by thapsigargin and phorbol 12-myristate 13-acetate (PMA), whereas, when induced by thrombin, it prevented a subset of tyrosine proteins. The selective inhibition of PKC by GF 109203X did not abolish tyrosine protein phosphorylation when induced by thrombin and thapsigargin. The results suggest that in human platelets tyrosine protein phosphorylation is dependent on [Ca2+]i, although direct PKC activation can also induce phosphorylation of tyrosine proteins.
我们研究了血小板刺激过程中细胞内钙离子水平（[Ca2+]i）和蛋白激酶C（PKC）对酪氨酸蛋白磷酸化的调节作用。我们发现，螯合细胞外钙可完全阻止毒胡萝卜素和佛波醇12-肉豆蔻酸酯13-乙酸酯（PMA）诱导的酪氨酸蛋白磷酸化，而当由凝血酶诱导时，它仅阻止一部分酪氨酸蛋白的磷酸化。GF 109203X对PKC的选择性抑制并未消除凝血酶和毒胡萝卜素诱导的酪氨酸蛋白磷酸化。结果表明，在人血小板中，酪氨酸蛋白磷酸化依赖于[Ca2+]i，尽管PKC的直接激活也可诱导酪氨酸蛋白的磷酸化。
