Graduate Student - Ph.D.

Picower Institute for Learning and Memory

Biology

Massachusetts Institute of Technology (Cambridge, MA)

Troy Littleton

Complexin functions as a vesicle fusion clamp to prevent synaptic vesicle exocytosis prior to calcium influx.

My thesis work has focused on analysis of the presynaptic SNARE-binding protein complexin in neurotransmitter release at Drosophila larval neuromuscular junctions. Characterization of synaptic communication has focused on action potential-triggered synaptic vesicle fusion, with spontaneous miniature potentials (minis) largely thought to represent background noise. However, during my thesis work, I have discovered that spontaneous release at synapses can drive synaptic growth and is regulated independently of evoked release by complexin. I generated a Drosophila knockout of complexin and, using genetic and electrophysiological approaches, provided the first in vivo evidence that complexin acts as a vesicle fusion clamp to prevent exocytosis of synaptic vesicles in the absence of calcium, prior to an action potential.

2006 Marine Biological Laboratory, Woods Hole, Neurobiology Course