细胞通讯在质膜受到受体相互作用的调节,附着力,信令,胞吐,和内吞蛋白。然而,这些纳米级复合物响应外部信号的组成和控制仍不清楚。这里,我们使用高分辨率和高通量荧光成像技术,绘制了生长因子受体和相关蛋白在人鳞状HSC3细胞质膜上单个网格蛋白包被结构的定位图.我们在对照细胞和用配体刺激的细胞之间发现了不同的蛋白质特征。质膜上的Clatthrin位点预先加载了一些受体,而不是其他受体。用表皮生长因子刺激诱导表皮生长因子的捕获和浓缩-,成纤维细胞生长因子-,和低密度脂蛋白受体(EGFR,FGFR,和LDLR)。调节蛋白包括泛素连接酶Cbl,还招募了支架Grb2和机械酶dynamin2。用药物单独破坏FGFR或EGFR可防止EGFR和FGFR的募集。我们的数据揭示了在网格蛋白包被部位的多种无关受体和调节因子之间的新型串扰,以响应单个生长因子的刺激,EGF。这种行为整合了生长因子信号,并允许对人类细胞质膜上的细胞外信号和药物产生复杂的反应。
■经典,包括表皮生长因子受体和成纤维细胞生长因子受体在内的受体通路被认为是独立的系统.然而,质膜是蛋白质相互作用的复杂环境,群集,信号,与细胞器联系在一起。例如,EGF激活后,EGFR在用蛋白网格蛋白包被的内部质膜上的位点处被捕获。这导致网格蛋白在粘附膜上平坦生长。这里,我们观察到在EGF刺激后网格蛋白与相关受体FGFR和无关LDLR的EGFR共同捕获。这是特异性的,因为其他受体不受影响。因此,单独但特定的受体系统在由网格蛋白组织的质膜上的纳米级区域共同组装并相互发出信号。这为治疗癌症等疾病提供了新的途径。
Cellular communication is regulated at the plasma membrane by the interactions of receptor, adhesion, signaling, exocytic, and endocytic proteins. Yet, the composition and control of these nanoscale complexes in response to external cues remain unclear. Here, we use high-resolution and high-throughput fluorescence imaging to map the localization of growth factor receptors and related proteins at single
clathrin-coated structures across the plasma membrane of human squamous HSC3 cells. We find distinct protein signatures between control cells and cells stimulated with ligands.
Clathrin sites at the plasma membrane are preloaded with some receptors but not others. Stimulation with epidermal growth factor induces a capture and concentration of epidermal growth factor-, fibroblast growth factor-, and low-density lipoprotein-receptors (EGFR, FGFR, and LDLR). Regulatory proteins including ubiquitin ligase Cbl, the scaffold Grb2, and the mechanoenzyme dynamin2 are also recruited. Disrupting FGFR or EGFR individually with drugs prevents the recruitment of both EGFR and FGFR. Our data reveals novel crosstalk between multiple unrelated receptors and regulatory factors at
clathrin-coated sites in response to stimulation by a single growth factor, EGF. This behavior integrates growth factor signaling and allows for complex responses to extracellular cues and drugs at the plasma membrane of human cells.