Figure 3.

Molecular markers for subsets of ooDSGCs. A, B, In situ hybridization for Cdh6 RNA (red) combined with anti-GFP antibody staining (green) reveals expression of Cdh6 in BD- but not DRD4-RGCs. Yellow arrows in A–H indicate double-labeled cells. Red arrows in A–H indicate marker-positive cells that do not express GFP. C, D, In situ hybridization for Col25a1 RNA (red) shows expression in GFP-labeled (green) BD-RGCs but not DRD4-RGCs. E, F, In situ hybridization for Mmp17 RNA (red) shows expression in GFP-labeled (green) DRD4- but not BD-RGCs. G, H, CART is a marker of both BD- and DRD4-RGCs as shown by immunostaining with anti-CART (red) and anti-GFP (green). Laminae marked in H (INL, inner nuclear layer; IPL, inner plexiform layer) apply to A–H, and K. Scale bars: 10 μm. I, J, Quantification of the fraction of RGCs expressing Cdh6, Col25a1, or Mmp17 at P14 (I) and at P7 (J) (n ≥ 44 for BD-RGCs, ≥104 for DRD4-RGCs, ≥1198 for all RGCs). K, MMP17 immunoreactivity in section from P14 retina. Antibody labels the putative starburst layers of the IPL, suggesting immunoreactivity in the dendrites of starburst amacrines and/or ooDSGCs. A subset of RGC cell bodies (arrows) as well as putative starburst amacrines (arrowheads) are labeled in the GCL and INL. Scale bar, 25 μm.