Coupling distances between synaptic vesicles and Ca2+ channels determine the efficacy of neurotransmission. Böhme et al. find that presynaptic scaffold complexes spatiotemporally control Unc13 isoforms to establish two independent release pathways at subsynaptic active zones: Unc13B defines nascent, loosely coupled synapses whereas Unc13A facilitates release at mature synapses by tight coupling between Ca2+ channels and synaptic vesicles.
- Mathias A Böhme
- Christina Beis
- Stephan J Sigrist