Figure 8. Loss of both NCKX2 and NCKX4 expressions leads to alteration of outer segment structure and cone cell death.
Confocal stacked images from flat mounted retinas from 3-month-old Nckx2-/- mice (a, c, e) and their littermate Nckx2/4 double knockout animals (b, d, f) stained with antibodies against S-opsin (a, b) or CNGA3 (c, d). A slice from the CNG3A stacked image is shown in e and f. Higher magnification of representative cells are shown in inset. Cones were labeled with peanut agglutinin (PNA) in representative flat mounted retina from 3-month-old (g) and 9-month-old (h) Nckx2/4 double knockout mice. Scale bar = 20 μm. The number of cones from retinas of control, Nckx4 knockout, and Nckx2/4 double knockout mice were counted and plotted (i). One-way ANOVA showed no differences in cone numbers in the group of 3-month-old mice (p=0.3), but significant (p<0.0001) reduction in cone numbers in the 9-month-old Nckx2/4 double knockouts compared to Nckx2-/- mice.