Dorahy D J, Berndt M C, Shafren D R, Burns G F
Cancer Research Unit, Faculty of Medicine and Health Sciences, University of Newcastle, Callaghan, New South Wales, Australia.
Biochem Biophys Res Commun. 1996 Jan 17;218(2):575-81. doi: 10.1006/bbrc.1996.0102.
Platelet activation and aggregation induced by agonists such as thrombin are accompanied by the phosphorylation of several proteins on tyrosine. Such tyrosine phosphorylation is dependent upon activation and ligand engagement of the major integrin receptor on the surface of platelets, glycoprotein (GP) IIb-IIIa (alpha IIb beta 3), but how this is accomplished is not known. The only platelet membrane GP known to associated with non receptor tyrosine kinases is CD36 (GPIV) which forms associations with pp60Fyn, pp62Yes, and pp54/58Lyn, and antibodies directed against CD36 activate platelets in a process dependent upon GPIIb-IIIa. These and other data suggest a physical association between the two membrane GPs, IIb-IIIa and CD36. By the use of immunoprecipitation of lysates of platelets that have been surface labeled and chemically crosslinked we show here that CD36 and GPIIb-IIIa are spatially associated on the surface of resting platelets.
凝血酶等激动剂诱导的血小板活化和聚集伴随着几种蛋白质的酪氨酸磷酸化。这种酪氨酸磷酸化依赖于血小板表面主要整合素受体糖蛋白(GP)IIb-IIIa(αIIbβ3)的活化和配体结合,但具体机制尚不清楚。已知唯一与非受体酪氨酸激酶相关的血小板膜糖蛋白是CD36(GPIV),它与pp60Fyn、pp62Yes和pp54/58Lyn形成关联,针对CD36的抗体在依赖于GPIIb-IIIa的过程中激活血小板。这些及其他数据表明两种膜糖蛋白IIb-IIIa和CD36之间存在物理关联。通过对经表面标记和化学交联的血小板裂解物进行免疫沉淀,我们在此表明CD36和GPIIb-IIIa在静息血小板表面在空间上相关联。