Fig. 1

Fig. 1

Generation of an UV cone-specific, doxycycline-inducible, self-reporting gene expression system. (A) Diagram of the construct used to generate the stable, transgenic line Tg(opn1sw1:rtTA, TRE:GFP), which expresses doxycycline (Dox)-inducible green fluorescent protein (GFP) specifically in UV cone photoreceptors. The UV opsin promoter (opn1sw1) drives expression of the reverse tetracycline-controlled transcriptional activator (rtTA) gene while the tetracycline responsive element (TRE) is upstream of GFP. (B, C) Confocal z-projections of retinal sections from 6 dpf Tg(opn1sw1:rtTA, TRE:GFP); alb^/ larvae labeled with an anti-UV opsin antibody (red). (B) GFP fluorescence (green) is not visible in the UV cones of larval transgenic zebrafish in the absence of Dox treatment. (C) GFP fluorescence is clearly visible in UV cones in transgenic larvae after 72 h of Dox treatment (3–6 dpf). (D) Confocal z-projection of retinal section from 6 dpf Tg(opn1sw1:rtTA, TRE:GFP); alb^/ larva labeled with an anti-GFP antibody (green) and an anti-Rhodopsin antibody (red). (D2) Corresponds to boxed area in D. Anti-GFP immunofluorescence (green) is visible in UV opsin cone photoreceptors while anti-Rhodopsin immunofluorescence (red) is visible in the outer segments of rod photoreceptors. (E, F) Confocal z-projections of the photoreceptor layer of retinas from adult Tg(opn1sw1:rtTA, TRE:GFP) zebrafish labeled with anti-UV opsin antibody (red). (E) GFP fluorescence (green) is not visible in the adult transgenic UV cones in the absence of Dox treatment. (F) GFP fluorescence is clearly visible in transgenic adult UV cones after 72 h of Dox treatment. dA, polyadenylation signal; Tol2, pTol integration site. Scale bars (B, E), 50 μm.