A Synaptic Vesicle-Associated Ca2 Channel Promotes Endocytosis and Couples Exocytosis to Endocytosis

作者：Yao Chi Kuang; Lin Yong Qi; Ly Cindy V; Ohyama Tomoko; Haueter Claire M; Moiseenkova Bell Vera Y; Wensel Theodore G; Bellen Hugo J^*

来源：Cell, 2009, 138(5): 947-960.

DOI：10.1016/j.cell.2009.06.033

Synaptic vesicle (SV) exo- and endocytosis are tightly coupled to sustain neurotransmission in presynaptic terminals, and both are regulated by Ca2 . Ca2 influx triggered by voltage-gated Ca2 channels is necessary for SV fusion. However, extracellular Ca2 has also been shown to be required for endocytosis. The intracellular Ca2 levels (<1 mu M) that trigger endocytosis are typically much lower than those (>10 mu M) needed to induce exocytosis, and endocytosis is inhibited when the Ca2 level exceeds 1 mu M. Here, we identify and characterize a transmembrane protein associated with SVs that, upon SV fusion, localizes at periactive zones. Loss of Flower results in impaired intracellular resting Ca2 levels and impaired endocytosis. Flower multimerizes and is able to form a channel to control Ca2 influx. We propose that Flower functions as a Ca2 channel to regulate synaptic endocytosis and hence couples exo- with endocytosis.

• 出版日期2009-9-4