Fig. 2: BRN3B represses melanopsin expression.
From: Genetic tuning of retinal ganglion cell subtype identity to drive visual behavior
A Schematic representation of the RNAscope retinal cross-sections protocol. BOpn4 and Brn3b mRNA expression in control (Opn4Cre/+; Brn3b+/+) and Brn3bcKO retinal sections. Brn3b mRNA expression is absent in Brn3bcKO ipRGCs (dashed ellipse) and still present in other RGCs (arrowheads). C (Left) Opn4 mRNA levels are significantly increased in ipRGCs Brn3bcKO (green, n = 216 cells) compared to control (black, n = 336 cells) littermates (P = 0.0001). (Right) Opn4 mRNA levels are increased in iBrn3bcKO (green, n = 288 cells) compared to control ipRGCs (black, n = 371 cells) (P = 0.0001). D (Left) Schematic representation of melanopsin immunolabeling in flat-mount retinas. (Right) melanopsin immunolabeling in ipRGCs of adult control and Brn3bcKO retinas. E, F melanopsin levels are increased in Brn3bcKO ipRGCs (E) (n = 600 cells/group, P = 0.0001), with an increased proportion of ipRGCs expressing high levels of melanopsin (F) (n = 600 cells/group). Q1–Q5: quintiles showing low (Q1) to high (Q5) melanopsin levels. G, H melanopsin levels are increased in iBrn3bcKO compared to control ipRGCs (G) (n = 800 cells in Vehicle; n = 761 in TMX, P = 0.0001), with an increased proportion of ipRGCs expressing high levels of melanopsin (H) (n = 800 cells in Vehicle; n = 761 in TMX). Source data are provided as a Source Data file. Lines are median values, ****P < 0.001, two-tailed Mann Whitney U test.
