Patel M D, Samelson L E, Klausner R D
J Biol Chem. 1987 Apr 25;262(12):5831-8.
Multiple kinases interact at the multicomponent murine T cell antigen receptor. Antigen induces serine phosphorylation of the 21-kDa gamma glycoprotein and tyrosine phosphorylation of p21, a distinct 21-kDa chain. We demonstrate that tyrosine phosphorylation is due to kinase activation, and that all phosphorylated p21 is associated with the antigen receptor. We also show that antigen leads to polyphosphoinositide metabolism and subsequent protein kinase C activation. The two phosphorylation events can be dissociated by protein kinase C depletion, which eliminates phorbol 12-myristate 13-acetate-induced serine but not tyrosine phosphorylation. Activation of a third kinase, cyclic AMP-dependent protein kinase, inhibits both serine and tyrosine events, yet this inhibition can be modulated by addition of the protein kinase C activator, phorbol 12-myristate 13-acetate. Receptor-mediated signal transduction may be understood as the interaction of multiple stimulatory and inhibitory kinase activities.
多种激酶在多组分小鼠T细胞抗原受体处相互作用。抗原诱导21 kDaγ糖蛋白的丝氨酸磷酸化以及一种独特的21 kDa链p21的酪氨酸磷酸化。我们证明酪氨酸磷酸化是由于激酶激活，并且所有磷酸化的p21都与抗原受体相关。我们还表明抗原导致多磷酸肌醇代谢以及随后的蛋白激酶C激活。这两种磷酸化事件可通过蛋白激酶C耗竭而分离，蛋白激酶C耗竭消除了佛波醇12 - 肉豆蔻酸酯13 - 乙酸酯诱导的丝氨酸磷酸化，但不影响酪氨酸磷酸化。第三种激酶，即环磷酸腺苷依赖性蛋白激酶的激活，会抑制丝氨酸和酪氨酸磷酸化事件，然而这种抑制作用可通过添加蛋白激酶C激活剂佛波醇12 - 肉豆蔻酸酯13 - 乙酸酯来调节。受体介导的信号转导可被理解为多种刺激性和抑制性激酶活性之间的相互作用。
