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Updated: Jul 28, 2026

Presynaptically Silent Synapses Studied with Light Microscopy
Published on: January 5, 2010
Munc13-1 is a presynaptic phorbol ester receptor that enhances neurotransmitter release
1Max-Planck-Institut für Experimentelle Medizin, Abt. Molekulare Neurobiologie, Göttingen, Bundesrepublik Deutschland.
Abstract:
Munc13-1, a mammalian homolog of C. elegans unc-13p, is thought to be involved in the regulation of synaptic transmission. We now demonstrate that Munc13-1 is a presynaptic high-affinity phorbol ester and diacylglycerol receptor with ligand affinities similar to those of protein kinase C. Munc13-1 associates with the plasma membrane in response to phorbol ester binding and acts as a phorbol ester-dependent enhancer of transmitter release when overexpressed presynaptically in the Xenopus neuromuscular junction. These observations establish Munc13-1 as a novel presynaptic target of the diacylglycerol second messenger pathway that acts in parallel with protein kinase C to regulate neurotransmitter secretion.
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