Ca(2+)-modulated vision-linked ROS-GC guanylate cyclase transduction machinery.
Vertebrate phototransduction depends on the reciprocal relationship between two-second messengers, cyclic GMP and Ca(2+). The concentration of both is reciprocally regulated including the dynamic synthesis of cyclic GMP by a membrane bound guanylate cyclase. Different from hormone receptor guanylate cyclases, the cyclases operating in phototransduction are regulated by the intracellular Ca(2+)-concentration via small Ca(2+)-binding proteins. Based on the site of their expression and their Ca(2+) modulation, this sub-branch of the cyclase family was named sensory guanylate cyclases, of which the retina specific forms are named ROS-GCs (rod outer segment guanylate cyclases). This review focuses on the structure and function of the ROS-GC subfamily present in the mammalian retinal neurons: photoreceptors and inner layers of the retinal neurons. Portions and excerpts of the review are from a previous chapter (Curr Top Biochem Res 6:111-144, 2004).
Koch
Karl-W
KW
AG Biochemistry, IBU, Faculty V, Carl von Ossietzky University, Oldenburg 26111, Germany.
Duda
Teresa
T
Sharma
Rameshwar K
RK
D000818:Animals; D020013:Calcium Signaling; D006162:Guanylate Cyclase / Q000502:physiology*; D006801:Humans; D055537:Light Signal Transduction; D055351:Retinal Neurons / Q000201:enzymology; D012374:Rod Cell Outer Segment / Q000201:enzymology; D014785:Vision, Ocular
D006162:Guanylate Cyclase