Mechanism of asynchronous neurotransmitter release from synapses
Rapid synchronous release followed by longer-lasting asynchronous release (AR) are the 2 forms of neurotransmitter releases but the mechanisms for AR remain unclear. Low concentrations of intracellular Ca2+ and Sr2 sustain the AR.
The researchers show that asynchronous neurotransmitter release prolongs the temporal window for postsynaptic firing in the cerebellum and hippocampus.
Synaptotagmin 7 (SYT7) partly mediates AR, but substantial AR persists in the absence of SYT7. The closely related SYT3 binds Ca2+ and Sr2+ with high affinity, making it a promising candidate to mediate AR.
Genetic deletion of SYT3 and SYT7 abolishes most asynchronous release, reducing information transfer between neurons indicating SYT3 mediates AR and show that SYT3 and SYT7 act as dominant mechanisms for AR.
https://www.cell.com/cell-reports/fulltext/S2211-1247(24)00924-0
