Study on the buildup principle of the plasma membrane signaling domains.

质膜包含各种形式的内陷，具有明显不同的物理构建原理。为了阐明结构域的形成机制，尤其是那些被笼蛋白包裹的凹坑和凹坑，晶格组装的动力学表征应该是一个重要的方法。研究了聚乙二醇型胆固醇醚(聚乙二醇型胆固醇醚)对笼状蛋白包裹的小窝和小窝结构/功能的影响。将该化合物加入培养的细胞中，可使细胞表面逐渐变得光滑。在这些细胞中积累了开放的网状蛋白包裹的凹坑，在细胞破裂的情况下，这些凹坑最终变得平坦，因为稍微多了一点聚乙二醇-胆固醇。这些结果有力地表明，包被坑弹性地区别于体膜相，也不同于小窝。接下来，我们分析了累积膜应力的影响。而单纯的聚乙二醇CHOL孵育对…的形态没有影响，我们发现大量的质膜小管装饰着DNA还介绍了生物素化的聚乙二醇胆碱(BPEGChol)和水杨酸。小管直径均匀(d[约等于]100 nm)，含有肌动蛋白细丝。生物化学上，bPEG-Chol诱导蛋白质酪氨酸磷酸化。分析表明，局部堆积的脂质包装缺陷引发了信号反应(S)，动员肌动蛋白来减少来自主体细胞体的压力。接下来，我们描述了K562人白血病细胞经冈田酸处理的反应，冈田酸是一种1型和2A型蛋白脱磷酸酶的抑制剂，对质膜上的物理压力的反应。当OKA单独诱导皮质F-肌动蛋白的片状积聚时，施加机械应力诱导了含有整个细胞F-肌动蛋白的膜结合体的萌发。这种富含肌动蛋白的小体的形成被F-肌动蛋白的修饰和蛋白激酶抑制剂所阻止。此外，当非受体酪氨酸激酶Fyn被敲除时，这种变化不会发生。在这个项目中，我们认为在OKA处理的细胞中，肌动蛋白微丝和一组确定的膜细胞器或表面蛋白之间存在特定的机械连接。较少

The plasma membrane contains various forms of invaginations with apparently different physical building principles. To specify the mechanisms of domain formation, particularly those for clathrin-coated pits and caveolae, the dynamical characterization of the lattice assembly should be an important approach. We addressed the effects of poly (ethylene glycol) cholesteryl ether (PEG-Chol) on the structure/function of clathrin-coated pit and caveolae. Addition of the compound to cultured cells induced progressive smoothening of the surface. In these cells were accumulated opened clathrin-coated pits, which ultimately became flat on occasion of the cell rupture by slightly more PEG-Chol. These results strongly suggested that coated-pit elastically differentiates from the bulk membrane phase and also from caveolae. Next, we analyzed the effect of accumulated membrane stress. Whereas simple incubation of PEG-Chol gave no morphological effect, we found numerous plasma membrane tubules decorate … More d with biotinylated PEG-Chol (bPEG-Chol) and SA were introduced. The tubules were homogeneous in diameter (d【approximately equal】100 nm) and contained actin filaments. Biochemically, bPEG-Chol induced tyrosinephosphorylation of proteins. The analysis suggested that local accumulation of lipid-packing defects evoked signaling reaction (s) that mobilize actin to reduce the stress from the main cell body. Next, we describe the responses of K562 human leukemia cells that were treated with okadaic acid, an inhibitor of type 1 and 2A protein dephosphatases, to physical stress on the plasma membrane. While OKA alone induced patchy accumulation of cortical F-actin, application of mechanical stresses induced budding of membrane-bound body containing the whole cell F-actin. The formation of this actin-rich body was prevented by modification of F-actin and also by protein kinase-inhibitors. Moreover, when a non-receptor tyrosine kinase Fyn was knocked-out, such change did not occur. In this project, we suggest the presence of the specific mechanical linkage between actin microfilaments and a defined set of membrane organelles or surfaces proteins in OKA-treated cells. Less