Phosphodiesterase 6B, cGMP Specific (PDE6B)

Photon absorption triggers a signaling cascade in rod photoreceptors that activates cGMP phosphodiesterase (PDE), resulting in the rapid hydrolysis of cGMP, closure of cGMP-gated cation channels, and hyperpolarization of the cell. PDE is a peripheral membrane heterotrimeric enzyme made up of alpha, beta, and gamma subunits. This gene encodes the beta subunit. Mutations in this gene result in retinitis pigmentosa and autosomal dominant congenital stationary night blindness. Multiple transcript variants encoding different isoforms have been found for this gene. PDE6B also has a C-terminal CAAX motif for posttranslational processing involving lipidation, proteolysis, and carboxymethylation. Human PDE6B shares 91.1% and 92.4% amino acid identity with bovine and mouse PDE beta subunits, respectively.