Competing on the edge

Fast-acting neurotransmitters can exit the synaptic cleft and bind to extrasynaptic receptors. This process is modulated by transmitter uptake mechanisms (transporters). A new study focusing on glutamate-mediated transmission in the cerebellum describes the specific role of neuronal transporters in modulating the access of glutamate to extrasynaptic metabotropic glutamate receptors, and reveals important consequences of extrasynaptic signaling on synaptic plasticity.