Figure 11

Nr2e1 ^frc/frc Müller glia misexpressed Brn3a cell-autonomously. Transverse retinal sections from P7 and P21 Nr2e1 ^+/+ and Nr2e1 ^frc/frc mice and P7 chimeras were immunostained for SOX-2, Brn3a, and Vimentin. a In P7 wild-type retinas, ganglion cells labeled with Brn3a (green) appeared as a different population from Müller glia labeled with SOX-2 (red, bracket). b In Nr2e1 ^frc/frc retinas, the marker Brn3a (green) was misexpressed in Müller-glia somas (red, bracket), and in processes that branch in the EPL and IPL, with termini in the GCL that resemble end-feet. c-f Immunostaining for the Müller-glia markers vimentin (red) and Brn3a (green) in P7 and P21 retinas. In P7 retinas, these markers did not co-express in (c) Nr2e1 ^+/+ retinas but they did in (d) Nr2e1 ^frc/frc retinas. This also occurred in P21 retinas where the markers did not co-express in (e) Nr2e1 ^+/+ retinas but they did in (f) Nr2e1 ^frc/frc retinas. d,f Inset boxes show a magnified view of the vimentin and Brn3a co-localization in Nr2e1 ^frc/frc Müller-glial processes. g In P7 Wt↔frc chimeras, misexpression of Brn3a (red) in Müller glia was seen in Nr2e1-mutant cells (EGFP positive, green) throughout the cell soma and processes, however, this was not seen in wild-type cells (EGFP negative) where Brn3a was only expressed in ganglion cells. Representative images of a 71 % Wt↔Wt and a 58 % Wt↔frc chimeric retina are shown. n = 3 for Nr2e1 ^+/+, n = 3 for Nr2e1 ^frc/frc, n = 4 for Wt↔Wt, n = 4 for Wt↔frc; EPL, Ectopic plexiform layer; GCL, ganglion cell layer; INL, inner nuclear layer; OPL, outer plexiform layer; Hoechst, nuclear counterstain (blue); scale bar = 50 μm