Visual pigment spectra of the comma butterfly, Polygonia c-album, derived from in vivo epi-illumination microspectrophotometry

Abstract

Visual pigment spectra of the comma butterfly, Polygonia c-album, derived from in vivo epiillumination nation microspectrophotometry Vanhoutte, KJA; Stavenga, DG Take-down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. 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 lightindependent 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.

Phototransduction and the Evolution of Photoreceptors

“…For rods on the other hand, this mechanism, which consumes relatively little energy by comparison to the other processes in the rod [87], has the advantage that in the dark essentially 100% of the rhodopsin can be reconstituted [95,96]. This may however be less important than it would seem, since microvillar eyes (at least in some species) also have the capability of completely regenerating their visual pigment in darkness [45,97]. …”

Metarhodopsin control by arrestin, light-filtering screening pigments, and visual pigment turnover in invertebrate microvillar photoreceptors

“…The blue-absorbing metarhodopsins belonging to the green-absorbing rhodopsins decay with an exponential time course that strongly depends on temperature: at 12.5, 23.0 and 26.5°C the decay half-time was assessed at about 50, 12 and 3 min, respectively (Bernard 1983b). The slower rhodopsin regeneration (half time at room temperature about 40 min; Vanhoutte and Stavenga, 2005) was found to be complex and dependent on the illumination history (Bernard 1983b). The experimental values obtained from butterflies dictated the time constants of visual pigment decay and regeneration (3 and 10 min, respectively) used in the calculations of Fig.…”

“…2a; from Stavenga 2010) and the green-absorbing rhodopsin R532 from the eye of the comma butterfly Polygonia c - album with its hypsochromic shifted, blue-green absorbing metarhodopsin M492 (Fig. 2b; from Vanhoutte and Stavenga 2005). The latter visual pigment can be taken as characteristic for the dominant, green-absorbing visual pigment class populating the majority of the photoreceptors in most insects (Hamdorf 1979; Briscoe and Chittka 2001; Briscoe et al 2003; Wakakuwa et al 2007).…”

“…If the quantum efficiency for photoconversion of bovine rhodopsin, γ R  = 0.67 (Dartnall 1972), is the same for fly rhodopsin, then the peak photosensitivity becomes β R,max  = 1.3 × 10 −8  μm 2 . (For similar calculations made for butterfly visual pigment, see Vanhoutte and Stavenga 2005.) In addition to the photosensitivity, calculation of the photoconversion rate constant (Eq.…”

Behavioral Responses of the SnailLymnaea acuminatatowards Photo and Chemo Attractants: A New Step in Control Program of Fasciolosis

“…It clearly indicates that variation in wavelength of light stimulus evokes differently to the photoreceptors of snails, so that there is a significant variation in the number of attracted snails by them. Higher attraction of snails towards light source as exposure period prolongs from 15 to 60 minutes indicates that variation in exposure time has significant effect on the attraction of L. acuminata towards light source because the conversion of rhodopsin to metarhodopsin and vice versa takes several minutes to hours depending upon the species [26,27].…”