Termination of photoreceptor responses.
Vertebrate and invertebrate photoreceptors respond with great speed and sensitivity to the onset of light; however, they also adapt quickly to constant light or a reduction of illumination. During the past year or so, new information has become available concerning the molecular mechanisms by which photoreceptors recover from and adapt to stimuli. These data have identified mechanisms that inactivate nearly every step of the vertebrate and invertebrate phototransduction pathways. Light-induced changes in the concentration of intracellular Ca2+ play an important role in photoreceptor recovery and adaptation. Recently, several proteins that may mediate the effects of Ca2+ on phototransduction have been identified.
Hurley
J B
JB
Howard Hughes Medical Institute, University of Washington, Seattle 98195.
D000222:Adaptation, Physiological / Q000502:physiology; D000818:Animals; D006801:Humans; D010786:Photoreceptor Cells / Q000502:physiology*; D017956:Photoreceptor Cells, Invertebrate / Q000502:physiology; D015398:Signal Transduction / Q000502:physiology