Fig 1: Rbp4-Cre neurons have synapses already at E14.5(A) Expression (circles) of selected genes (Data S1) related to neuronal communication.95,96 Radius of circles: fraction of cells expressing the gene; color of circles: mean normalized transcripts per cell (log2).(B) Immunostaining of Rbp4-Cre neurons (green), Snap25 (presynaptic; gray), PSD-95 (postsynaptic; magenta), Hoechst (blue). Right: Zoom (arrows: colocalization of Snap25 and PSD-95).(C and D) DAB staining of Rbp4-Cre neurons in tissue prepared for EM.97(E) Synaptic contacts involving Rbp4-Cre neurons (DAB, darker cells), presynaptic vesicles (red arrow) and postsynaptic densities (blue arrowhead).Scale bars: 10 µm (left, B), 2 µm (right, B), 25 µm (C), 25 µm (D), 100 nm (E).