Spontaneous clustering

Abstract

Stimulus-dependent release of neurotransmitter is essential for communication between nerve cells, but although stimulus-independent, or ‘spontaneous’, vesicle release was first observed over fifty years ago, understanding its significance has been more elusive. Now, a July Science paper reports that spontaneous vesicle exocytosis is vital for clustering of glutamate receptors during development. By studying Drosophila with alterations in different synaptic vesicle proteins, researchers found that mutants that demonstrated evoked but not spontaneous release of neurotransmitter had normal receptor clustering, but in mutants that lacked both evoked and spontaneous release, glutamate receptor clustering in the neuromuscular junction was disrupted. As receptor clustering is not altered by glutamate receptor antagonists in this system, other vesicular neurochemicals might mediate this phenomenon. LO