Voltage-dependent calcium channels at the plasma membrane, but not vesicular channels, couple exocytosis to endocytosis.

ABSTRACT: Although calcium influx triggers endocytosis at many synapses and non-neuronal secretory cells, the identity of the calcium channel is unclear. The plasma membrane voltage-dependent calcium channel (VDCC) is a candidate, and it was recently proposed that exocytosis transiently inserts vesicular calcium channels at the plasma membrane, thus triggering endocytosis and coupling it to exocytosis, a mechanism suggested to be conserved from sea urchin to human. Here, we report that the vesicular membrane, when inserted into the plasma membrane upon exocytosis, does not generate a calcium current or calcium increase at a mammalian nerve terminal. Instead, VDCCs at the plasma membrane, including the P/Q-type, provide the calcium influx to trigger rapid and slow endocytosis and, thus, couple endocy

SUBMITTER: Xue L 

PROVIDER: S-EPMC3401380 | biostudies-literature | 2012 Jun

REPOSITORIES: biostudies-literature