Phototransduction motifs and variations.
Seeing begins in the photoreceptors, where light is absorbed and signaled to the nervous system. Throughout the animal kingdom, photoreceptors are diverse in design and purpose. Nonetheless, phototransduction-the mechanism by which absorbed photons are converted into an electrical response-is highly conserved and based almost exclusively on a single class of photoproteins, the opsins. In this Review, we survey the G protein-coupled signaling cascades downstream from opsins in photoreceptors across vertebrate and invertebrate species, noting their similarities as well as differences.
Yau
King-Wai
KW
Solomon H. Snyder Department of Neuroscience and Center for Sensory Biology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA. kwyau@mail.jhmi.edu
Hardie
Roger C
RC
D000818:Animals; D006801:Humans; D055537:Light Signal Transduction; D017956:Photoreceptor Cells, Invertebrate / Q000378:metabolism; D020419:Photoreceptor Cells, Vertebrate; D043562:Receptors, G-Protein-Coupled / Q000378:metabolism*
D043562:Receptors, G-Protein-Coupled