Journal Article

Synaptic weight set by Munc13-1 supramolecular assemblies

Namiki, Shigeyuki, Sugao, Kohtaroh, Asanuma, Daisuke, Sakamoto, Hirokazu, Takikawa, Kenji, Ariyoshi, Tetsuroh, Hirose, Kenzo, Taiko, Isamu, Kimpara, Naoya

2018

Overview

The weight of synaptic connections, which is controlled not only postsynaptically but also presynaptically, is a key determinant in neuronal network dynamics. The mechanisms controlling synaptic weight, especially on the presynaptic side, remain elusive. Using single-synapse imaging of the neurotransmitter glutamate combined with super-resolution imaging of presynaptic proteins, we identify a presynaptic mechanism for setting weight in central glutamatergic synapses. In the presynaptic terminal, Munc13-1 molecules form multiple and discrete supramolecular self-assemblies that serve as independent vesicular release sites by recruiting syntaxin-1, a soluble N-ethylmaleimide-sensitive-factor attachment receptor (SNARE) protein essential for synaptic vesicle exocytosis. The multiplicity of these Munc13-1 assemblies affords multiple stable states conferring presynaptic weight, potentially encoding several bits of information at individual synapses. Supramolecular assembling enables a stable synaptic weight, which confers robustness of synaptic computation on neuronal circuits and may be a general mechanism by which biological processes operate despite the presence of molecular noise.

• Publisher: Nature Publishing Group
• Subject: Assemblies / Bassoon music / Biological activity / Exocytosis / Glutamatergic transmission / Image resolution / N-Ethylmaleimide / Neurosciences / Proteins / Robustness (mathematics) / SNAP receptors / Synapses / Synaptic strength / Syntaxin / Syntaxin 1