title: Blue and double-peaked green receptors depend on ommatidial type in the eye of the Japanese yellow swallowtail Papilio xuthus.
abstract: The compound eye of the butterfly Papilio xuthus is composed of three spectrally distinct types of ommatidia. We investigated the blue and double-peaked green receptors that are encountered distally in type I and III ommatidia, by means of intracellular recordings, in vivo fluorescence microscopy, and histology. The blue receptors are R1 and/or R2 photoreceptors; they contain the same mRNA encoding the opsin of the blue-absorbing visual pigment. However, here we found that the sensitivity in the UV wavelength region strongly depends on the ommatidial type; the blue receptors in type I ommatidia have a distinctly depressed UV sensitivity, which is attributed to lateral filtering in the fused rhabdom. In the main, fronto-ventral part of the eye, the R3 and R4 photoreceptors of all ommatidia contain the same set of two mRNAs encoding the opsins of green-absorbing visual pigments, PxL1 and PxL2. The spectral sensitivities are double-peaked, but the UV sensitivity of the R3 and R4 photoreceptors in type I ommatidia appears to be reduced, similar to that of the co-localized blue receptors.
authors.affiliation: Graduate School of Integrated Science, Yokohama City University, Japan.
authors.forename: Michiyo
authors.initials: M
authors.lastname: Kinoshita
authors.forename: Daisuke
authors.initials: D
authors.lastname: Kurihara
authors.forename: Aiko
authors.initials: A
authors.lastname: Tsutaya
authors.forename: Kentaro
authors.initials: K
authors.lastname: Arikawa
mesh_terms: D000818:Animals; D002080:Butterflies / Q000502:physiology*; D003118:Color Perception / Q000502:physiology*; D005123:Eye / Q000033:anatomy & histology; D008297:Male; D009799:Ocular Physiological Phenomena; D017956:Photoreceptor Cells, Invertebrate / Q000737:chemistry*