Figure 3. The choice of gene promoter and the presence of the gene’s 5′ untranslated region influence the level of reporter gene expression in cultured rat Müller cells. Microscopic analysis is in agreement with the flow cytometry data (Figure 2), and therefore serves as a rapid, qualitative approach to screening experimental promoters. eGFP expression is demonstrated for the 500 bp promoter fragments either with (right) or without (left) the 5′ UTR for each of the nine genes analyzed (A-I). Shown in (J) are control transfections with the backbone vector (pFTM3GW; left), or a vector containing the 1178 bp human ubiquitin-C promoter (pFUGW; right). Scale bar in (A) equals 10 µm.