Neuronal synapses are stabilised by activity-dependent vesicular release from oligodendrocyte precursor cells

Abstract Activity-dependent regulation of synapses has long been attributed to interactions between neurons alone. Here, using in vivo imaging in the zebrafish visual system we show that one type of glia called the oligodendrocyte precursor cell (OPC) closely interacts with pre-synapses of retinal ganglion cell (RGC) axons, and exhibits activity-dependent Vamp2/3-mediated vesicular release. Critically, blocking OPC vesicle release using botulinum toxin, and silencing OPC activity integration through dampening calcium signalling, destabilises RGC pre-synapses. These observations suggest that OPCs provide a non-neuronal pathway for activity-dependent feedback to shape circuit wiring.