Smythe E, Pypaert M, Lucocq J, Warren G
Department of Biochemistry, University, Dundee, Scotland.
J Cell Biol. 1989 Mar;108(3):843-53. doi: 10.1083/jcb.108.3.843.
Biochemical and morphological techniques were used to demonstrate the early steps in the endocytosis of transferrin in broken A431 cells. After binding 125I-transferrin, the cells were broken by scraping and then warmed. 125I-transferrin became inaccessible to exogenous anti-transferrin antibody providing a measure of the internalization process. Parallel morphological experiments using transferrin coupled to horseradish peroxidase confirmed internalization in broken cells. The process was characterized and compared with endocytosis in intact cells and showed many similar features. The system was used to show that both the appearance of new coated pits and the scission of coated pits to form coated vesicles were dependent on the addition of cytosol and ATP whereas invagination of pits was dependent on neither.
利用生化和形态学技术来证明破碎的A431细胞中转铁蛋白内吞作用的早期步骤。结合125I-转铁蛋白后，通过刮擦使细胞破碎，然后加热。外源性抗转铁蛋白抗体无法识别125I-转铁蛋白，这为内化过程提供了一种衡量方法。使用与辣根过氧化物酶偶联的转铁蛋白进行的平行形态学实验证实了破碎细胞中的内化作用。对该过程进行了表征，并与完整细胞中的内吞作用进行了比较，发现有许多相似的特征。该系统用于表明新包被小窝的出现以及包被小窝分裂形成包被小泡均依赖于细胞溶质和ATP的添加，而小窝的内陷则两者均不依赖。
