Effect of synthetic cholesterol derivative, PEG-Chol, on caveolar invagination

我们解决了胆固醇衍生物，聚（乙二醇）胆固醇醚（PEG-Chol）的结构/功能的网格蛋白包被的小窝和小窝的影响。向培养的细胞中添加化合物诱导表面进行性平滑。当掺入量超过表面积的10%当量时，K562细胞中的液体胞饮作用受到抑制，但转铁蛋白的内吞作用不受抑制。在A431细胞中，不仅观察到这种活性，而且还观察到小窝变平。开放的网格蛋白包被的小凹在这些细胞中积累。我们在这里建议，功能网格蛋白晶格比典型的磷脂双层更硬。接下来，我们研究了皮质肌动蛋白和网格蛋白涂层坑/脂筏之间可能的联系。由于大量的膜动力学是在蛋白磷酸化水平上调节的，我们通过冈田酸（OKA）在K562细胞中引入了过度磷酸化的蛋白质条件。而OKA则诱导斑片状聚集， ...更多信息 在皮层肌动蛋白离子的作用下，我们发现随后用胆固醇的生物素化聚（乙二醇）衍生物（bPEG-Chol）与通过链霉亲和素（SA）的积累相结合的细胞诱导了许多随后积累并从主细胞体中挤出的philopodia样突起。富含肌动蛋白的小体与波形蛋白束和线粒体簇相关联。此外，电子显微镜还发现了网格蛋白包被的小坑。此外，筏成分，CD 59和神经节苷脂GM 1也积累。同样，筏组件Thy-1也积累在小鼠T细胞，但当非受体酪氨酸激酶Fyn敲除，这种变化没有发生。值得注意的是，在抗体介导的CD 59和神经节苷脂GM 1的蓄积后也观察到极化蓄积。由于Fyn是已知的集中在肌动蛋白丰富的领域，包括合并的脂筏，我们在这里建议，一定的机械应力是由Fyn重组成一个单一的质量在OKA处理的细胞整个细胞肌动蛋白和肌动蛋白连接的蛋白质。少

We addressed the effects of a cholesterol derivative, 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 smoothenting of the surface. When the incorporated amount exceeded 10% equivalent of the surface area, fluid pinocytosis, but not endocytosis of transferrin, were inhibited in K562 cells. In A431 cells, not only this activity but also the flattening of caveolae was observed. Opened clathrin-coated pits were accumulated in these cells. We suggest here that the functional clathrin-lattice is much more stiffer than typical phospholipid bilayers. Next, we investigated possible linkage between cortical actin and clathrin coated pits/ lipid-rafts. Since a large body of memebrane dynamics is regulated at the level of protein phosphorylation, we introduced hyper-phosphorylated protein condition in a K562 cell by okadaic acid (OKA). While OKA induced patchy accumulat … More ion of cortical actin, we found subsequent treatement of the cells with biotinylated poly (ethylene glycol) derivative of cholesterol (bPEG-Chol) in conjunction with accumulation via streptavidin (SA) induced numerous phillopodia-like protrusions that are subsequently accumulated and extruded from the main cell body. The actin-rich body was associated with a bundle of vimentin and cluster of mitochondria. Moreover, clathrin-coated pits that were localized by electron microscopy. Moreover, raft-components, CD59 and ganglioside GM1 were also accumulated. Similarly, a raft component Thy-1 was also accumulated in murine T cells but, when non-receptor tyrosine kinase Fyn was knocked-out, such change did not occur. Notably, polarized accmulation was also observed after antibody-mediated accmulation of CD59 and ganglioside GM1. Since Fyn is known to be concentrated in actin-rich domains including coalesced lipid-rafts, we here suggest that certain mechanical stress is transmitted by Fyn to reorganize whole cellular actin and actin-linked proteins into a single mass in OKA-treated cells. Less