Analysis of the long-term effect of Cre activity on RPE cells of adult <i>Ai14;RPE-Tyrosinase-CreEr</i>^<i>T2</i> mice.

A: Electron micrographs of adult RPE at lower (left) and higher magnification (right), showing no phonotypical abnormalities after short- and long-term Cre activity. B: Flatmount preparations of adult RPE after short-term and long-term Cre activity, showing no morphological changes in cells expressing tdTomato expression (red) and no expression in untreated mice. The tight junction-associated protein ZO-1 (green) was labeled to visualize the cell borders. C: qRT-PCR shows no difference in expression of mature RPE markers (Lrat, Rpe65 and Ttr) relative to housekeeping gene (Tbp). Ai14;Cre: Ai14;RPE-Tyrosinase-CreErT2. ST: short-term effect of tamoxifen-treatment. LT: long-term effect of tamoxifen-treatment. BM: Bruch’s membrane. Scale bars: (A) right: 5 μm, left: 1 μm, (B) 10 μm.