Fig. 2: ipRGCs drive LTTA.
From: Light tunes long-term threat avoidance behavior in male mice
A Scheme of melanopsin expression in ipRGCs. B Representative animal position traces of control and melanopsin-null (Opn4−/−) male mice during the Test phase of the LTTA previously exposed to 0 or 6.6% Michelson contrast. C Time in threat zone (TZ) during the Test phase normalized to time in TZ during the Pre-exposure phase in control (black) and Opn4−/− (red) male mice exposed to 0 (n = 15 mice/group) (P = 0.162) or 6.6% (n = 14 control mice, n = 11 Opn4−/− mice) (P = 0.002) Michelson contrast. D Opn4 gene locus in WT (top), Opn4fl/fl before (middle) and after (bottom) Cre recombination. E Scheme of intravitreal injection of Vehicle, AAV2-hSyn-mCherry (control) or AAV2-hSyn-Cre-P2A-TdTomato in Opn4fl/fl male mice (left) melanopsin immunolabeling in flat-mount retinas (right). F Representative images of melanopsin immunolabeling in ipRGCs of Opn4fl mice followed by control or AAV2-hSyn-Cre-P2A-TdTomato injections. Arrowheads pointing ipRGC somas in retinas from AAV-Cre injected mice. G Representative animal position traces of Opn4fl/fl male mice during the Test phase of the LTTA previously exposed to 6.6% Michelson contrast. H Time in TZ during the Test phase normalized to time in TZ during the Pre-exposure phase in control (n = 5, gray) and AAV2-hSyn-Cre-P2A-TdTomato (n = 7, red) Opn4fl/fl mice exposed to 6.6% Michelson contrast (P = 0.010). I Scheme of glutamate release ablation specifically from ipRGCs. (J) Representative animal position traces of Vglut2cKO male mice during the Test phase of the LTTA previously exposed to 6.6% Michelson contrast. K Time in TZ during the Test phase normalized to time in TZ during the Pre-exposure phase in Vglut2cKO (n = 11, purple) and control (n = 5, gray) male mice exposed to 6.6% Michelson contrast (P = 0.020). L Schematic representations of Brn3b-positive ipRGC ablation in Brn3bDTA mice. M Representative animal position traces during the Test phase of the LTTA paradigm. N Time in TZ during the Test phase normalized to time in TZ during the Pre-exposure phase of Brn3bDTA (n = 11, pink) and control (n = 6, gray) littermate male mice (P = 0.038). Source data are provided as a Source Data file. All data are Mean ± SEM, n.s. (not significant) P > 0.05; *P < 0.05; **P < 0.01. Two-sided Student t and Mann-Whitney U tests.
