title: Moonlight detection by Drosophila's endogenous clock depends on multiple photopigments in the compound eyes.
abstract: Many organisms change their activity on moonlit nights. Even the fruit fly Drosophila melanogaster responds to moonlight with a shift of activity into the night, at least under laboratory conditions. The compound eyes have been shown to be essential for the perception of moonlight, but it is unknown which of the 5 rhodopsins in the eyes are responsible for the observed moonlight effects. Here, we show that the outer (R1-R6) and inner (R7 and R8) photoreceptor cells in a fly's ommatidium interact in a complex manner to provoke the moonlight effects on locomotor activity. The shift of the evening activity peak into the night depends on several rhodopsins in the inner and outer photoreceptor cells. The increase in relative nocturnal activity in response to moonlight is mainly mediated by the rhodopsin 6-expressing inner photoreceptor cell R8 together with the rhodopsin 1-expressing outer receptor cells (R1-R6), whereas just rhodopsin 1 of R1 to R6 seems necessary for increasing nocturnal activity in response to increasing daylight intensity.
authors.affiliation: Neurobiology and Genetics, Theodor-Boveri Institute, Biocenter, University of Würzburg, Würzburg, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Schlichting
authors.forename: Rudi
authors.initials: R
authors.lastname: Grebler
authors.forename: Nicolai
authors.initials: N
authors.lastname: Peschel
authors.forename: Taishi
authors.initials: T
authors.lastname: Yoshii
authors.forename: Charlotte
authors.initials: C
authors.lastname: Helfrich-Förster
mesh_terms: D000818:Animals; D001683:Biological Clocks / Q000502:physiology*; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism; D004331:Drosophila melanogaster / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D005123:Eye / Q000166:cytology / Q000378:metabolism / Q000528:radiation effects*; D007150:Immunohistochemistry; D008027:Light; D018613:Microscopy, Confocal; D016081:Moon; D009043:Motor Activity / Q000502:physiology; D009154:Mutation; D009799:Ocular Physiological Phenomena / Q000528:radiation effects; D017956:Photoreceptor Cells, Invertebrate / Q000378:metabolism / Q000502:physiology*; D012243:Rhodopsin / Q000235:genetics / Q000378:metabolism
chemical_list: D029721:Drosophila Proteins; D012243:Rhodopsin
keywords: circadian clock; entrainment; masking; rhodopsins