PMID:1961249

Citation	Ranganathan, R, Harris, GL, Stevens, CF and Zuker, CS (1991) A Drosophila mutant defective in extracellular calcium-dependent photoreceptor deactivation and rapid desensitization. Nature 354:230-2
Abstract	CALCIUM is involved in the adaptation of vertebrate photoreceptors to light and may have a similar role in invertebrate phototransduction. But the molecular mechanisms mediating this stimulus-dependent regulation are not well understood in any G protein-coupled transduction system. We have developed a preparation of isolated Drosophila photoreceptors that has allowed us to carry out an electrophysiological characterization of the light-activated response in these sensory neurons using patch-clamp techniques. We report here that extracellular calcium entering through the light-activated conductance is a key regulator of both the activation and deactivation phases of the phototransduction cascade, and that inaC mutant photoreceptors are specifically defective in the calcium-dependent deactivation mechanism. These data suggest that the light-dependent calcium influx inactivates this cascade through a biochemical pathway that requires the inaC gene product, and that this mechanism represents a molecular basis for stimulus-dependent regulation of visual transduction in Drosophila photoreceptors.
Links	PubMed Online version:10.1038/354230a0
Keywords	Animals; Calcium/pharmacology; Cesium/pharmacology; Chlorides; Dose-Response Relationship, Drug; Drosophila melanogaster/genetics; Drosophila melanogaster/physiology; Electrophysiology; Photoreceptor Cells/physiology; Potassium Chloride/pharmacology; Signal Transduction/drug effects; Sodium Chloride/pharmacology; Tromethamine/pharmacology
edit table

Annotations

Gene product	Qualifier	GO ID	GO term name	Evidence Code	with/from	Aspect	Notes	Status
edit table

References

See Help:References for how to manage references in GONUTS.