National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, MD 20892, USA.
Sci Signal. 2009 Dec 22;2(102):pe80. doi: 10.1126/scisignal.2102pe80.
Cell surface area is maintained in most cells by coupling exocytotic activity to compensatory endocytosis, a process that specifically retrieves membrane inserted by exocytosis. Although such coupling mechanisms seem to be ubiquitous, the mechanisms through which these membrane trafficking events are linked have remained elusive. A mechanism for coupling exocytosis to endocytosis in fruit fly nerve terminals that depends on the exocytotic insertion of vesicular calcium channels into the plasma membrane has recently been identified. This coupling mechanism resembles one previously described in sea urchin eggs. Here, I compare the similarities and differences of the processes involved in linking exocytosis to endocytosis in these two invertebrate systems and speculate on whether the vertebrate coupling mechanism might also depend on vesicular channels.
细胞表面面积在大多数细胞中通过将胞吐活性与补偿性内吞作用耦合来维持，这是一种专门回收由胞吐作用插入的膜的过程。尽管这种偶联机制似乎无处不在，但这些膜运输事件是如何联系起来的机制仍然难以捉摸。最近，在果蝇神经末梢中发现了一种依赖于囊泡钙通道插入质膜的将胞吐作用与内吞作用偶联的机制。这种偶联机制类似于先前在海胆卵中描述的一种机制。在这里，我比较了这两个无脊椎动物系统中连接胞吐作用和内吞作用的过程的异同，并推测脊椎动物的偶联机制是否也可能依赖于囊泡通道。
