Phosphodiesterase 6D, cGMP Specific (PDE6D)

cGMP is the cellular second messenger involved in the transduction of visual signals in retinal rod and cone cells. Constitutively synthesized by guanylate cyclase, its level is tightly controlled by modulating its degradation by a specific phosphodiesterase (cGMP-PDE). The enzyme characterized from bovine retinal rod cells is made of a catalytic core consisting of a membrane-associated alpha-beta dimer. An inhibitory gamma subunit enables transducin to regulate the rate of cGMP degradation according to incoming visual signals. The delta subunit (PDE6D) seems to play a role in stabilizing the catalytic dimer from membranes.Amino acid analysis predicted that the putative mammalian protein is soluble and acidic, contains 2 N-linked glycosylation sites, and lacks hydrophobic transmembrane domains.