The anti-apoptotic effect of Notch-1 requires p56lck-dependent, Akt/PKB-mediated signaling in T cells
The anti-apoptotic effect of Notch-1 requires p56lck-dependent, Akt/PKB-mediated signaling in T cells
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DOI：
10.1074/jbc.m309924200
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发表时间：
2004-01-23
影响因子：
4.8
通讯作者：
Sarin, A
中科院分区：
文献类型：
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作者：
Sade, H;Krishna, S;Sarin, A
跨膜受体Notch家族参与了不同细胞类型的多种细胞决策。本文以模型细胞系为实验系统，研究notch -1介导的T细胞抗凋亡功能的机制。Notch1/激活的Notch （AcN1）胞内结构域的异位表达增加了凋亡抑制剂（IAP）家族、Bcl-2家族和flice样抑制剂蛋白（FLIP）的抗凋亡蛋白的表达，并抑制由多种刺激触发的死亡，这些刺激激活了人类和小鼠T细胞系的内在或外在凋亡途径。麻可抑制acn1依赖性诱导的抗凋亡蛋白和抗凋亡功能。使用药物抑制剂和显性阴性方法，我们描述了磷脂酰肌醇3-激酶（PI3K）依赖的丝氨酸-苏氨酸激酶Akt/PKB激活在调节acn1介导的抗凋亡功能和FLIP和IAP家族蛋白表达中的功能作用。利用缺乏T细胞特异性Src家族蛋白酪氨酸激酶p56（lck）的细胞系，并通过重组方法证明p56lck是notch -1介导的Akt/PKB功能激活所必需的。此外，Src酪氨酸激酶抑制剂PP2取消了异位表达acn1介导的抗凋亡功能和p56（lck）磷酸化。我们提供的证据表明，内源性Notch-1与p56（lck）和PI3K相关，但Akt/PKB不与Notch1.p56（lck）共同免疫沉淀。PI3K复杂。最后，我们演示了Notch1.p56（lck）。PI3K复合物存在于体外激活的原代T细胞中，并在细胞因子白细胞介素-2的培养中持续存在。
The Notch family of transmembrane receptors have been implicated in a variety of cellular decisions in different cell types. Here we investigate the mechanism underlying Notch-1-mediated anti-apoptotic function in T cells using model cell lines as the experimental system. Ectopic expression of the intracellular domain of Notch1/activated Notch (AcN1) increases expression of antiapoptotic proteins of the inhibitors of apoptosis (IAP) family, the Bcl-2 family, and the FLICE-like inhibitor protein (FLIP) and inhibits death triggered by multiple stimuli that activate intrinsic or extrinsic pathways of apoptosis in human and murine T cell lines. Numb inhibited the AcN1-dependent induction of anti-apoptotic proteins and anti-apoptotic function. Using pharmacological inhibitors and dominant-negative approaches, we describe a functional role for phosphatidylinositol 3-kinase (PI3K)-dependent activation of the serine-threonine kinase Akt/PKB in the regulation of AcN1-mediated anti-apoptotic function and the expression of FLIP and IAP family proteins. Using a cell line deficient for the T cell-specific, Src family protein, the tyrosine kinase p56(lck) and by reconstitution approaches we demonstrate that p56lck is required for the Notch-1-mediated activation of Akt/PKB function. Furthermore, the Src tyrosine kinase inhibitor, PP2, abrogated ectopically expressed AcN1-mediated anti-apoptotic function and phosphorylation of p56(lck). We present evidence that endogenous Notch-1 associates with p56(lck) and PI3K but that Akt/PKB does not co-immunoprecipitate with the Notch1.p56(lck).PI3K complex. Finally, we demonstrate that the Notch1.p56(lck).PI3K complex is present in primary T cells that have been activated in vitro and sustained in culture with the cytokine interleukin-2.