Figure 3. P23H rod opsin expression in WT and sCnx cells. P23H-GFP opsin is retained in the endoplasmic reticulum (ER) and forms intracellular inclusions (arrowed in the inset panel) in wild-type (WT; A) and sCnx mouse embryonic fibroblasts (MEFs; B). Scale bar equals 10 μm. C: western blotting of untagged P23H rod opsin with mAb 1D4 of 15 μg of soluble protein revealed the same glycoform pattern of expression for P23H opsin in WT or sCnx cell lysates (as indicated). This representative blot has been selected for similar rod opsin expression level. The position of molecular weight markers in kDa are indicated on the left. D: The incidence of P23H inclusion formation in WT and sCnx MEFs was quantified. Cells were transfected with P23H-opsin-green fluorescent protein (GFP), and the percentages of transfected cells with intracellular inclusions after 24 h were scored blind to experimental status (the noninclusion positive cells had predominant ER staining). Five groups of greater than 100 cells expressing GFP opsin were counted. Error bars represent ±2 SEM. Statistical analysis was performed using ANOVAR followed by posthoc tests. The asterisk indicates p<0.05.