Changes in the zebrafish eye morphology in the gosh mutant.

A: Expression of zebrafish aipl1b gene at 3 dpf (left) and adult stage (right). aipl1b mRNA is expressed exclusively in photoreceptors, especially all types of cones at the adult stage. B: Microscopic images of wild-type and gosh mutant retinas at 3 months-post-fertilization. In wild-type, retinal ganglion cell layer (GCL), inner nuclear layer (INL), inner plexiform layer (IPL), and nuclear layers of rod and cone photoreceptors are distinct, and rod outer segment (OS) is observed at the outer-most layer of the retina. In the gosh mutant, only cone cell layer is absent but rods are not affected, suggesting that cones progressively degenerate in the gosh mutant.