Figure 1. The appearance of RPE cell culture infected with RCAS-ash1 differed from that of the control. A: The control retinal pigment epithelium (RPE) cell culture infected with Replication Competent Avian Splice (RCAS)-green fluorescent protein (GFP; left) showed dark pigmentation, but the experimental culture infected with RCAS-achaete-scute homolog 1 (ash1; right) remained un-pigmented, except at a few places. B: The control culture displayed a monolayer-appearance. C: The experimental culture contained clusters or aggregates of cells. Arrows point to cell clusters. Scale bars represents 100 μm.