Lubinski J, Huet C
Biol Cell. 1984;52(2):119-27. doi: 10.1111/j.1768-322x.1985.tb00329.x.
When tissue culture cells were maintained at 37 degrees C in a serum-free medium for 4 hr no change in the number of coated pits could be detected using ultrastructural techniques. However, the number of coated vesicles was highly significantly increased, being 179% more than in the control cultures. If the cells were put back into a medium supplemented with 5% calf serum, the number of coated pits was unchanged, but the number of coated vesicles decreased and returned to the control level within a few minutes. The same results were obtained when using ligands such as Low Density Lipoprotein or alpha-2-macroglobulin which are known to be internalized via coated structures. It is concluded that coated pits appear and disappear at equal rates and that coated vesicles can accumulate independently. It is suggested that this could be due to the presence of a large reserve of soluble clathrin. This pool would have a low turnover rate because cycloheximide did not block coated vesicle accumulation over the period studied.
当组织培养细胞在无血清培养基中于37℃维持4小时时，使用超微结构技术未检测到被膜小窝数量的变化。然而，被膜小泡的数量显著增加，比对照培养物中的数量多179%。如果将细胞放回补充有5%小牛血清的培养基中，被膜小窝的数量不变，但被膜小泡的数量减少，并在几分钟内恢复到对照水平。当使用诸如低密度脂蛋白或α-2-巨球蛋白等已知通过被膜结构内化的配体时，也获得了相同的结果。得出的结论是，被膜小窝以相等的速率出现和消失，并且被膜小泡可以独立积累。有人提出，这可能是由于存在大量可溶性网格蛋白储备。由于在研究期间环己酰亚胺并未阻止被膜小泡的积累，因此这个储备池的周转率会很低。
