MOLECULAR-CLONING OF THE MOUSE GRB2 GENE - DIFFERENTIAL INTERACTION OF THE GRB2 ADAPTER PROTEIN WITH EPIDERMAL GROWTH-FACTOR AND NERVE GROWTH-FACTOR RECEPTORS
MOLECULAR-CLONING OF THE MOUSE GRB2 GENE - DIFFERENTIAL INTERACTION OF THE GRB2 ADAPTER PROTEIN WITH EPIDERMAL GROWTH-FACTOR AND NERVE GROWTH-FACTOR RECEPTORS
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DOI：
10.1128/mcb.13.9.5500
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发表时间：
1993-09-01
影响因子：
5.3
通讯作者：
BARBACID, M
中科院分区：
文献类型：
--
作者：
SUEN, KL;BUSTELO, XR;BARBACID, M
我们报道了小鼠grb 2基因的分离和分子特征。该基因的产物Grb 2蛋白与秀丽隐杆线虫sem-5基因产物和人GRB 2蛋白高度相关，并显示出相同的SH 3-SH 2-SH 3结构基序。原位杂交研究表明，小鼠grb 2基因在整个胚胎发育（E9.5至PO）中广泛表达。然而，grb 2转录物不是均匀分布的，并且在某些组织中（例如，胸腺），它们似乎在发育过程中受到调节。最近的遗传和生物化学证据表明Grb 2蛋白参与了连接细胞表面酪氨酸激酶受体和Ras的信号通路。我们已经调查了协会的Grb 2蛋白与表皮生长因子（EGF）和神经生长因子（NGF）受体在PC 12嗜铬细胞瘤细胞。EGF处理PC 12细胞导致Grb 2与活化的EGF受体快速结合，这是由Grb 2 SH 2结构域介导的相互作用。然而，Grb 2不与NGF激活的Trk受体结合。在异位表达Trk受体的NIH 3 T3细胞中，NGF的促有丝分裂信号传导也发生，而Grb 2和Trk之间没有可检测的关联。这些结果表明，虽然EGF和NGF可以激活PC 12细胞中的Ras信号通路，但只有EGF受体可能通过与Grb 2的直接相互作用来实现。最后，谷胱甘肽S-转移酶融合蛋白的结合研究表明，Grb 2结合两个不同的蛋白质子集，分别由其SH 2和SH 3结构域识别。这些观察结果进一步支持了Grb 2是模块化衔接蛋白的概念。
We report the isolation and molecular characterization of the mouse grb2 gene. The product of this gene, the Grb2 protein, is highly related to the Caenorhabditis elegans sem-5 gene product and the human GRB2 protein and displays the same SH3-SH2-SH3 structural motifs. In situ hybridization studies revealed that the mouse grb2 gene is widely expressed throughout embryonic development (E9.5 to PO). However, grb2 transcripts are not uniformly distributed, and in certain tissues (e.g., thymus) they appear to be regulated during development. Recent genetic and biochemical evidence has implicated the Grb2 protein in the signaling pathways that link cell surface tyrosine kinase receptors with Ras. We have investigated the association of the Grb2 protein with epidermal growth factor (EGF) and nerve growth factor (NGF) receptors in PC12 pheochromocytoma cells. EGF treatment of PC12 cells results in the rapid association of Grb2 with the activated EGF receptors, an interaction mediated by the Grb2 SH2 domain. However, Grb2 does not bind to NGF-activated Trk receptors. Mitogenic signaling of NGF in NIH 3T3 cells ectopically expressing Trk receptors also takes place without detectable association between Grb2 and Trk. These results suggest that whereas EGF and NGF can activate the Ras signaling pathway in PC12 cells, only the EGF receptor is likely to do so through a direct interaction with Grb2. Finally, binding studies with glutathione S-transferase fusion proteins indicate that Grb2 binds two distinct subsets of proteins which are individually recognized by its SH2 and SH3 domains. These observations add further support to the concept that Grb2 is a modular adaptor protein.