Figure 3.
Injection and in vivo electroporation of pcna morpholino during constant light exposure knocks down PCNA levels. Dark-adapted adult albino zebrafish were injected and electroporated with either the pcna morpholino 1 (pcna MO1), pcna morpholino 2 (pcna MO2), 5-base mismatch morpholino 1 (5bmm MO1), or 5-base mismatch morpholino 2 (5bmm MO2) and exposed to constant intense light. Retinas were harvested at 1, 2, and 3 days into the light treatment and immunolabeled with PCNA (shown in green) and rhodopsin (shown in blue). In the uninjected control retinas (panels A–C) and the 5-base mismatch control retinas (panels D–I), light exposure results in a progressive accumulation of PCNA-positive cells within the INL and ONL and a loss of rhodopsin. Arrows and double arrowheads indicate the relative positions of the PCNA-positive cells in the ONL and in INL, respectively. In contrast, the pcna morphant retinas lack any PCNA-positive cells throughout the light exposure (Panels J–O). Scale bar: panel A, 25 µm (A–O).