In vivo identification of the interaction site of ErbB2 extracellular domain with its autoinhibitor
In vivo identification of the interaction site of ErbB2 extracellular domain with its autoinhibitor
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DOI：
10.1002/jcp.20409
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发表时间：
2005-12-01
影响因子：
5.6
通讯作者：
Guo, N
中科院分区：
文献类型：
--
作者：
Hu, PL;Feng, JN;Guo, N
对ErbB2转化电位的直接干扰已成为人们非常感兴趣的课题。关键ErbB2外畴相互作用的破坏可能导致治疗各种肿瘤的新治疗方法。基于ErbB外结构域亚结构域设计合理的肽模拟物可以抑制ErbB受体信号转导。模拟物可以特异性结合ErbB受体并阻断受体间的相互作用，从而在体外抑制erbb2过表达细胞的生长。本研究通过计算机辅助分子模型构建了ErbB2和ErbB2外结构域复合物的自身抑制剂herstatin的三维结构。在SI结构域确定herstatin在ErbB2外结构域的结合位点。构建ErbB2外结构域突变体。在herstatin和ErbB2外结构域共表达的活细胞中，首次分析了ErbB2外结构域及其突变体与herstatin的相互作用。通过免疫沉淀、共聚焦显微镜和荧光共振能量转移（FRET）证实ErbB2外结构域S1结构域是与herstatin的相互作用位点。herstatin在ErbB2外结构域的结合区可能是药物设计的潜在靶点区域。
Direct interference with the transforming potential of ErbB2 has become a subject of great interest. Disruption of critical ErbB2 ectodomain interactions may lead to novel therapeutic approaches for the treatment of various tumors. The ErbB receptor signaling can be inhibited by rationally designed peptide mimetics based on the subdomains of ErbB ectodomain. The mimetics can bind to the ErbB receptor specifically and block inter-receptor interactions, resulting in the growth inhibition of ErbB2-overexpressing cells in vitro. In this study, three-dimensional structure of herstatin, an autoinhibitor of ErbB2 and ErbB2 ectodomain complex was constructed by computer-aided molecular modeling. The binding site on ErbB2 ectodomain for herstatin was determined at SI domain. The mutants of ErbB2 ectodomain were constructed. The interactions of ErbB2 ectodomain and its mutants with herstatin were analyzed for the first time in living cells that coexpressed herstatin and ErbB2 ectodomain or the mutants. The S1 domain in ErbB2 ectodomain was verified as the interaction site with herstatin by immunoprecipitation, confocal microscopy, and fluorescence resonance energy transfer (FRET). The binding region of herstatin on ErbB2 ectodomain might be a potential target region for the drug design.