Fig. 7
TdTomato is expressed in retinal pigment epithelium. A Shows corresponding brightfield (left) and red fluorescence (right) images of intact eyes dissected from a transgenic tdTomato E18 embryo (+) and a wild-type sibling (−). The back of the transgenic eye is fluorescent, except for the circular optic disk (arrow), where the retina is interrupted by outgoing axons of the optic nerve. B Shows similar images of eyes from a 1.5-month old pair of transgenic (+) and wild-type (−) siblings. C Shows immunofluorescence for tdTomato in a cryostat section taken transverse to the plane of the retina from a 3-week old transgenic mouse. The immunoreactive arc corresponds in location to the retinal pigment epithelium (RPE), known to express TTR. Intermittent immunostained large cells in the retinal layer were also observed (arrowheads)