Rhodopsin activation causes retinal degeneration in Drosophila rdgC mutant.
Drosophila rdgC (retinal degeneration-C) mutants show normal retinal morphology and photoreceptor physiology at young ages. Dark-reared rdgC flies retain this wild-type phenotype, but light-reared mutants undergo retinal degeneration. rdgC photoreceptors with low levels of rhodopsin as a result of vitamin A deprivation or a mutant rhodopsin (ninaE) gene fail to show rdgC-induced degeneration even after prolonged light treatment, demonstrating that degeneration occurs as a result of light stimulation of rhodopsin. Analysis of norpA; rdgC flies shows that the norpA-encoded phospholipase C, the target enzyme of the G protein activated by rhodopsin, is not required for rdgC-induced degeneration. Thus the rdgC+ gene product is required to prevent retinal degeneration that results from a previously unrecognized consequence of rhodopsin stimulation.
Steele
F
F
Department of Biological Sciences, University of Notre Dame, Indiana 46556.
O'Tousa
J E
JE
D000375:Aging; D000818:Animals; D002874:Chromosome Mapping; D004330:Drosophila / Q000235:genetics* / Q000502:physiology; D004594:Electrophysiology / Q000379:methods; D008027:Light; D008854:Microscopy, Electron; D009154:Mutation; D010641:Phenotype; D010786:Photoreceptor Cells / Q000254:growth & development / Q000502:physiology* / Q000648:ultrastructure; D012162:Retinal Degeneration; D012168:Retinal Pigments / Q000502:physiology*; D012243:Rhodopsin / Q000502:physiology*; D010738:Type C Phospholipases / Q000378:metabolism
D012168:Retinal Pigments; D012243:Rhodopsin; D010738:Type C Phospholipases