Calmodulin regulation of calcium stores in phototransduction of Drosophila

TitleCalmodulin regulation of calcium stores in phototransduction of Drosophila
Publication TypeJournal Article
Year of Publication1997
AuthorsArnon A, Cook B, Montell C, Selinger Z, Minke B
JournalScience
Volume275
Pagination1119-21
Date Published1997 Feb 21
ISSN0036-8075
KeywordsAnimals, Animals, Genetically Modified, Caffeine, Calcium, Calcium-Transporting ATPases, Calmodulin, Drosophila, Enzyme Inhibitors, Light, Patch-Clamp Techniques, Photoreceptor Cells, Invertebrate, Ryanodine, Signal Transduction, Thapsigargin
Abstract

Phototransduction in Drosophila occurs through the ubiquitous phosphoinositide-mediated signal transduction system. Major unresolved questions in this pathway are the identity and role of the internal calcium stores in light excitation and the mechanism underlying regulation of Ca2+ release from internal stores. Treatment of Drosophila photoreceptors with ryanodine and caffeine disrupted the current induced by light, whereas subsequent application of calcium-calmodulin (Ca-CaM) rescued the inactivated photoresponse. In calcium-deprived wild-type Drosophila and in calmodulin-deficient transgenic flies, the current induced by light was disrupted by a specific inhibitor of Ca-CaM. Furthermore, inhibition of Ca-CaM revealed light-induced release of calcium from intracellular stores. It appears that functional ryanodine-sensitive stores are essential for the photoresponse. Moreover, calcium release from these stores appears to be a component of Drosophila phototransduction, and Ca-CaM regulates this process.

Alternate JournalScience
PubMed ID9027311
Grant ListEY03529 / EY / NEI NIH HHS / United States
EY10852 / EY / NEI NIH HHS / United States