Songyang Z, Shoelson S E, McGlade J, Olivier P, Pawson T, Bustelo X R, Barbacid M, Sabe H, Hanafusa H, Yi T
Department of Cell Biology, Harvard Medical School, Boston, Massachusetts.
Mol Cell Biol. 1994 Apr;14(4):2777-85. doi: 10.1128/mcb.14.4.2777-2785.1994.
Src homology 2 (SH2) domains provide specificity to intracellular signaling by binding to specific phosphotyrosine (phospho-Tyr)-containing sequences. We recently developed a technique using a degenerate phosphopeptide library to predict the specificity of individual SH2 domains (src family members, Abl, Nck, Sem5, phospholipase C-gamma, p85 subunit of phosphatidylinositol-3-kinase, and SHPTP2 (Z. Songyang, S. E. Shoelson, M. Chaudhuri, G. Gish, T. Pawson, W. G. Haser, F. King, T. Roberts, S. Ratnofsky, R. J. Lechleider, B. G. Neel, R. B. Birge, J. E. Fajardo, M. M. Chou, H. Hanafusa, B. Schaffhausen, and L. C. Cantley, Cell 72:767-778, 1993). We report here the optimal recognition motifs for SH2 domains from GRB-2, Drk, Csk, Vav, fps/fes, SHC, Syk (carboxy-terminal SH2), 3BP2, and HCP (amino-terminal SH2 domain, also called PTP1C and SHPTP1). As predicted, SH2 domains from proteins that fall into group I on the basis of a Phe or Tyr at the beta D5 position (GRB-2, 3BP2, Csk, fps/fes, Syk C-terminal SH2) select phosphopeptides with the general motif phospho-Tyr-hydrophilic (residue)-hydrophilic (residue)-hydrophobic (residue). The SH2 domains of SHC and HCP (group III proteins with Ile, Leu, of Cys at the beta D5 position) selected the general motif phospho-Tyr-hydrophobic-Xxx-hydrophobic, also as predicted. Vav, which has a Thr at the beta D5 position, selected phospho-Tyr-Met-Glu-Pro as the optimal motif. Each SH2 domain selected a unique optimal motif distinct from motifs previously determined for other SH2 domains. These motifs are used to predict potential sites in signaling proteins for interaction with specific SH2 domain-containing proteins. The Syk SH2 domain is predicted to bind to Tyr-hydrophilic-hydrophilic-Leu/Ile motifs like those repeated at 10-residue intervals in T- and B-cell receptor-associated proteins. SHC is predicted to bind to a subgroup og these same motifs. A structural basis for the association of Csk with Src family members is also suggested from these studies.
Src同源2（SH2）结构域通过与特定的含磷酸酪氨酸（磷酸化-Tyr）序列结合，为细胞内信号传导提供特异性。我们最近开发了一种利用简并磷酸肽文库来预测单个SH2结构域（src家族成员、Abl、Nck、Sem5、磷脂酶C-γ、磷脂酰肌醇-3-激酶的p85亚基以及SHPTP2）特异性的技术（Z. 宋阳、S. E. 肖尔森、M. 乔杜里、G. 吉什、T. 帕森、W. G. 哈泽、F. 金、T. 罗伯茨、S. 拉特诺夫斯基、R. J. 莱克勒德、B. G. 尼尔、R. B. 比尔格、J. E. 法贾多、M. M. 周、H. 花房、B. 沙夫豪森和L. C. 坎特利，《细胞》72:767 - 778，1993年）。我们在此报告来自GRB - 2、Drk、Csk、Vav、fps/fes、SHC、Syk（羧基末端SH2）、3BP2和HCP（氨基末端SH2结构域，也称为PTP1C和SHPTP1）的SH2结构域的最佳识别基序。如所预测的，基于β D5位置的苯丙氨酸或酪氨酸而属于第一组的蛋白质的SH2结构域（GRB - 2、3BP2、Csk、fps/fes、Syk羧基末端SH2）选择具有磷酸化-Tyr-亲水（残基）-亲水（残基）-疏水（残基）一般基序的磷酸肽。SHC和HCP（β D5位置具有异亮氨酸、亮氨酸或半胱氨酸的第三组蛋白质）的SH结构域也如所预测的那样选择了磷酸化-Tyr-疏水-Xxx-疏水的一般基序。在β D5位置具有苏氨酸的Vav选择了磷酸化-Tyr-甲硫氨酸-谷氨酸-脯氨酸作为最佳基序。每个SH2结构域都选择了一个独特的最佳基序，该基序不同于先前为其他SH2结构域确定的基序。这些基序用于预测信号蛋白中与特定含SH2结构域蛋白相互作用的潜在位点。预计Syk SH2结构域会与酪氨酸-亲水-亲水-亮氨酸/异亮氨酸基序结合，就像在T细胞和B细胞受体相关蛋白中以10个残基间隔重复出现的那些基序一样。预计SHC会与这些相同基序的一个亚组结合。这些研究还提出了Csk与Src家族成员关联的结构基础。
