zGc3 expression is coupled to Aipl1 and Pde6c in zebrafish photoreceptors.
(a) Labeling of wild-type, gosh, and els mutant retinas and pineal eyes at 7 dpf with anti-formaldehyde-fixed cGMP antibody (green) and zpr1 antibody (magenta). Control wild-type retinas show an undetectable level of cGMP. gosh and els mutant retinas show similar results, except that a few photoreceptors near the CMZ show very high accumulation of cGMP (arrow). On the other hand, pineal photoreceptors are positive for cGMP in gosh and els mutants, but not in wild type fish. (b) Western blot of wild-type, gosh and els mutant heads with anti-zGc3 antibody. A band of ~120 kDa is detected in wild-type heads, but disappears in both gosh and els mutant heads. (c) Semi-quantitative PCR of gc3 mRNA expression in wild-type, and gosh or els mutant embryos. mRNA levels are similar between wild-type, and gosh or els mutant embryos.