A complexin fusion clamp regulates spontaneous neurotransmitter release and synaptic growth.
Neuronal signaling occurs through both action potential-triggered synaptic vesicle fusion and spontaneous release, although the fusion clamp machinery that prevents premature exocytosis of synaptic vesicles in the absence of calcium is unknown. Here we demonstrate that spontaneous release at synapses is regulated by complexin, a SNARE complex-binding protein. Analysis of Drosophila melanogaster complexin null mutants showed a marked increase in spontaneous fusion and a profound overgrowth of synapses, suggesting that complexin functions as the fusion clamp in vivo and may modulate structural remodeling of neuronal connections by controlling the rate of spontaneous release.
Huntwork
Sarah
S
The Picower Institute for Learning and Memory, Department of Biology and Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Building 46, Room 3243, Cambridge, Massachusetts 02139, USA.
Littleton
J Troy
JT
D000818:Animals; D030801:Animals, Genetically Modified; D029721:Drosophila Proteins / Q000378:metabolism; D004331:Drosophila melanogaster; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D009469:Neuromuscular Junction / Q000502:physiology*; D009474:Neurons / Q000502:physiology*; D018377:Neurotransmitter Agents / Q000378:metabolism*; D050600:SNARE Proteins / Q000378:metabolism; D009435:Synaptic Transmission / Q000502:physiology; D013572:Synaptic Vesicles / Q000378:metabolism
D029721:Drosophila Proteins; D009419:Nerve Tissue Proteins; D018377:Neurotransmitter Agents; D050600:SNARE Proteins