Guanylate Cyclase 2F (GUCY2F)

GUCY2F is a guanylyl cyclase found predominantly in photoreceptors in the retina. The encoded protein is thought to be involved in resynthesis of cGMP after light activation of the visual signal transduction cascade, allowing a return to the dark state. This protein is a single-pass type I membrane protein. Defects in this gene may be a cause of X-linked retinitis pigmentosa.It migrated as an approximately 115-kD protein on Western blots of bovine rod outer segments. Membrane GC activity of recombinant RetGC2 protein expressed in mammalian cells was stimulated by bovine p24, the retinal cyclase activator, in a calcium-sensitive manner. In situ hybridization to monkey tissues revealed that RetGC2 mRNA is found only in the outer nuclear layer and inner segments of photoreceptor cells.