Irving B A, Chan A C, Weiss A
Department of Physiology, University of California, San Francisco 94143.
J Exp Med. 1993 Apr 1;177(4):1093-103. doi: 10.1084/jem.177.4.1093.
A conserved sequence motif has been identified in a number of signaling subunits associated with hematopoietic cell antigen receptors. Here, we characterize signaling by a 17 amino acid motif that is triplicated in the T cell antigen receptor zeta chain. Analysis of zeta truncations and constructs containing the isolated motif demonstrates that this motif is sufficient for the induction of both proximal and distal events associated with T cell activation. Stimulation of truncations that contain either one, two, or three copies of the motif results in induction of an identical pattern of tyrosine phosphoproteins. Moreover, triplication of the NH2-terminal zeta motif results in enhanced signaling, suggesting a redundant role in signal amplification for the three motifs in zeta. Finally, we demonstrate the association of a recently identified protein tyrosine kinase ZAP-70 with this motif, and provide evidence for its involvement in zeta function.
在许多与造血细胞抗原受体相关的信号亚基中已鉴定出一个保守的序列基序。在此，我们对一个17个氨基酸的基序的信号传导进行了表征，该基序在T细胞抗原受体ζ链中重复出现三次。对ζ链截短体和含有分离基序的构建体的分析表明，该基序足以诱导与T细胞活化相关的近端和远端事件。对含有该基序一个、两个或三个拷贝的截短体的刺激导致诱导出相同模式的酪氨酸磷酸化蛋白。此外，NH2末端ζ基序的三重重复导致信号增强，表明ζ链中的三个基序在信号放大中具有冗余作用。最后，我们证明了最近鉴定的蛋白酪氨酸激酶ZAP-70与该基序的关联，并提供了其参与ζ链功能的证据。
