Fig. 3. (A-D) Xbh1 promotes ganglion cell differentiation in lipofection experiments. Retinal precursors lipofected with GFP+vector DNA alone (B), or with GFP+Xbh1 (C,D). Retinal layers are separated by dashed lines (B,C) and are indicated in B as follows: GCL, ganglion cell layer; INL, inner nuclear layer; ONL, outer nuclear layer; l, lens. (A) Distribution of retinal cell types in lipofected clones. Ph, photoreceptors; H, horizontal; B, bipolars; Am, amacrine; G, ganglion; Mü, Müller. The proportion of each cell type is represented as average±s.e.m. The experiment has been repeated at least three times for both GFP and Xbh1. In the experiment represented here, n=3907 cells from 26 retinae for GFP, and n=2799 cells from 25 retinae for Xbh1. Asterisks represent significant differences between Xbh1 and GFP, as calculated by Student's t-test (^*P<0.05, ^**P<0.01, ^***P<0.001). (D) Lower magnification image of section shown in C; GFP-positive axons extend into the optic nerve (arrows).