BiP, a molecular chaperone found in the ER, is more abundant around the cell nuclei of maturing lens fibers in two month old Cx50 mutant mice (arrows). In wildtype lenses (A, B, C), BiP is predominately seen in the lens epithelium, with lower levels distributed through the lens fibers. In contrast, BiP staining is more prominent in maturing lens fibers, particularly in the perinuclear ER (arrows) in both Cx50 G22R (D, E, F,) and Cx50 S50P (G, H,I) homozygous mutant lenses. J- Quantitation of BiP levels in the lens epithelium, transition zone and cortical fibers using ImageJ. P values reported represent ANOVA analysis performed on results obtained from at least three biological replicates. Red-BiP; Blue-DRAQ5 (DNA); e-epithelial cells; f- fiber cells; tz-transition zone; Scale bar=77μm