The synthetic peptide neurotransmitter in the presynaptic vector supports efficient gene transfer to connected neurons.

The experimental design was as detailed in Fig 3 legend. Alternating sections containing POR cortex were analyzed for expression from the presynaptic vector and either the targeted or control postsynaptic vector, using immunofluorescent costaining. The upper layers of POR cortex were examined. (A-D) Delivery of this presynaptic vector, followed by the targeted postsynaptic vector, supports efficient gene transfer to connected neurons; (A) His tag-IR (Texas red-conjugated secondary antibody), (B) GFP-IR (FITC-conjugated secondary antibody), (C) merge, and (D) merge, an enlarged area showing specific transduced axons either proximal to, or distant from, a transduced dendrite. Arrows, transduced axons; arrowheads, transduced dendrites. (E-H) Delivery of this presynaptic vector followed by the untargeted, control postsynaptic vector supported only a low level of gene transfer to connected neurons; (E) His tag-IR, (F) flag-IR (FITC-conjugated secondary antibody), (G) merge, and (H) merge, an enlarged area with His tag-IR axons and flag-IR dendrites that are distant from each other. Scale bars: (A-C and E-G) 50 μm, and (D and H) 50 μm.