Moreover, synaptic responses recorded from iN cells showed signs of short-term synaptic plasticity, such as depression of IPSCs and facilitation of EPSCs during a high frequency stimulus train (Fig. 4c–d, lower panels). The presence of synaptic contacts between iN cells and cortical neurons was independently corroborated by the immunocytochemical detection of synapsin-positive puncta surrounding MAP2-positive dendrites originating from EGFP-positive cells (Fig. 4e–f). We were also able to observe synaptic responses in similar experiments performed with iN cells derived from TTFs, (Supplementary Fig. 4). These data demonstrate that iN cells can form functional postsynaptic compartments and receive synaptic inputs from cortical neurons.
