Trans-Synaptic Signaling through the Glutamate Receptor Delta-1 Mediates Inhibitory Synapse Formation in Cortical Pyramidal Neurons

Fossati et al. show that, in stark contrast to other iGluRs, the glutamate receptor delta-1 (GluD1) operates at inhibitory, rather than excitatory, synapses in the cortex. GluD1 mediates trans-synaptic signaling governing the formation of synapses between specific interneurons and pyramidal neurons.