Plasmid encoding pAAV2/2-CAG-palmitoylation tag-mCherry-WPRE was used to generate recombinant AAV2/2 expressing membrane-tagged Cherry. To label SACs in retina expressing cC3-mCherry or cA1-mCherry, we used rAAV2/2-CBA-YC3.6-WPRE expressing a calcium sensor that includes cytosolic YFP and used here for visualization of neuronal morphology41. Recombinant AAV2/2-CAG-memb-mCherry and rAAV2/2-YC3.6 were prepared at the Harvard Gene Therapy Institute (1–2 × 1012 genome copies/mL, Boston, MA). Optimal titers of 1–2 × 109 viral genome particles/mL for AAV2/2-CAG-memb-mCherry and 2 × 1010 viral genome particles/mL for rAAV2/2- YC3.6 were prepared in phosphate-buffered saline (PBS, pH = 7.4). rAAV2/9 expressing GFP and mCherry were generated and generously provided by Dawen Cai and Kimberly Cohen in our laboratory; high titer virus was produced at the University of Pennsylvania Vector Core.
