title: Visual pigment spectra of the comma butterfly, Polygonia c-album, derived from in vivo epi-illumination microspectrophotometry.
abstract: The visual pigments in the compound eye of the comma butterfly, Polygonia c-album, were investigated in a specially designed epi-illumination microspectrophotometer. Absorption changes due to photochemical conversions of the visual pigments, or due to light-independent visual pigment decay and regeneration, were studied by measuring the eye shine, i.e., the light reflected from the tapetum located in each ommatidium proximal to the visual pigment-bearing rhabdom. The obtained absorbance difference spectra demonstrated the dominant presence of a green visual pigment. The rhodopsin and its metarhodopsin have absorption peak wavelengths at 532 nm and 492 nm, respectively. The metarhodopsin is removed from the rhabdom with a time constant of 15 min and the rhodopsin is regenerated with a time constant of 59 min (room temperature). A UV rhodopsin with metarhodopsin absorbing maximally at 467 nm was revealed, and evidence for a blue rhodopsin was obtained indirectly.
authors.affiliation: Department of Neurobiophysics, University of Groningen, Nijenborgh 4, 9747, Groningen, the Netherlands.
authors.forename: Kurt J A
authors.initials: KJ
authors.lastname: Vanhoutte
authors.forename: Doekele G
authors.initials: DG
authors.lastname: Stavenga
mesh_terms: D000818:Animals; D002080:Butterflies / Q000502:physiology*; D003118:Color Perception / Q000502:physiology; D003624:Darkness; D008027:Light; D009799:Ocular Physiological Phenomena; D010775:Photic Stimulation; D012168:Retinal Pigments / Q000502:physiology*
chemical_list: D012168:Retinal Pigments