scholarly journals New Primers for the Avian SWS1 Pigment Opsin Gene Reveal New Amino Acid Configurations in Spectral Sensitivity Tuning Sites

2009 ◽  
Vol 100 (6) ◽  
pp. 784-789 ◽  
Author(s):  
A. Odeen ◽  
O. Hastad
Keyword(s):  
Amino Acid ◽  
Spectral Sensitivity ◽  
Opsin Gene

scholarly journals Spectral sensitivity in Onychophora (velvet worms) revealed by electroretinograms, phototactic behaviour and opsin gene expression

2015 ◽  
Vol 218 (6) ◽  
pp. 915-922 ◽  
Author(s):  
H. Beckmann ◽  
L. Hering ◽  
M. J. Henze ◽  
A. Kelber ◽  
P. A. Stevenson ◽  
...  
Keyword(s):  
Gene Expression ◽  
Spectral Sensitivity ◽  
Opsin Gene ◽  
Velvet Worms ◽  
Phototactic Behaviour

scholarly journals Evolution of ultraviolet vision in shorebirds (Charadriiformes)

2009 ◽  
Vol 6 (3) ◽  
pp. 370-374 ◽  
Author(s):  
Anders Ödeen ◽  
Olle Håstad ◽  
Per Alström
Keyword(s):  
Amino Acid ◽  
Visual Pigment ◽  
Colour Vision ◽  
Gene Tree ◽  
Amino Acid Position ◽  
Opsin Gene ◽  
Avian Evolution ◽  
Ultraviolet Vision ◽  
Rynchops Niger ◽  
Sws1 Opsin Gene

Diurnal birds belong to one of two classes of colour vision. These are distinguished by the maximum absorbance wavelengths of the SWS1 visual pigment sensitive to violet (VS) and ultraviolet (UVS). Shifts between the classes have been rare events during avian evolution. Gulls (Laridae) are the only shorebirds (Charadriiformes) previously reported to have the UVS type of opsin, but too few species have been sampled to infer that gulls are unique among shorebirds or that Laridae is monomorphic for this trait. We have sequenced the SWS1 opsin gene in a broader sample of species. We confirm that cysteine in the key amino acid position 90, characteristic of the UVS class, has been conserved throughout gull evolution but also that the terns Anous minutus, A. tenuirostris and Gygis alba , and the skimmer Rynchops niger carry this trait. Terns, excluding Anous and Gygis , share the VS conferring serine in position 90 with other shorebirds but it is translated from a codon more similar to that found in UVS shorebirds. The most parsimonious interpretation of these findings, based on a molecular gene tree, is a single VS to UVS shift and a subsequent reversal in one lineage.

scholarly journals Parallelism of amino acid changes at the RH1 affecting spectral sensitivity among deep-water cichlids from Lakes Tanganyika and Malawi

2005 ◽  
Vol 102 (15) ◽  
pp. 5448-5453 ◽  
Author(s):  
T. Sugawara ◽  
Y. Terai ◽  
H. Imai ◽  
G. F. Turner ◽  
S. Koblmuller ◽  
...  
Keyword(s):  
Amino Acid ◽  
Spectral Sensitivity ◽  
Deep Water

scholarly journals Mix and Match Color Vision: Tuning Spectral Sensitivity by Differential Opsin Gene Expression in Lake Malawi Cichlids

2005 ◽  
Vol 15 (19) ◽  
pp. 1734-1739 ◽  
Author(s):  
Juliet W.L. Parry ◽  
Karen L. Carleton ◽  
Tyrone Spady ◽  
Aba Carboo ◽  
David M. Hunt ◽  
...  
Keyword(s):  
Gene Expression ◽  
Color Vision ◽  
Spectral Sensitivity ◽  
Lake Malawi ◽  
Opsin Gene ◽  
Mix And Match

scholarly journals Rapid adaptive evolution of colour vision in the threespine stickleback radiation

2016 ◽  
Vol 283 (1830) ◽  
pp. 20160242 ◽  
Author(s):  
Diana J. Rennison ◽  
Gregory L. Owens ◽  
Nancy Heckman ◽  
Dolph Schluter ◽  
Thor Veen
Keyword(s):  
Local Adaptation ◽  
Spectral Sensitivity ◽  
Parallel Evolution ◽  
Sensory Modality ◽  
Threespine Stickleback ◽  
Ice Age ◽  
Opsin Gene ◽  
Light Conditions ◽  
Light Spectrum ◽  
Last Ice Age

Vision is a sensory modality of fundamental importance for many animals, aiding in foraging, detection of predators and mate choice. Adaptation to local ambient light conditions is thought to be commonplace, and a match between spectral sensitivity and light spectrum is predicted. We use opsin gene expression to test for local adaptation and matching of spectral sensitivity in multiple independent lake populations of threespine stickleback populations derived since the last ice age from an ancestral marine form. We show that sensitivity across the visual spectrum is shifted repeatedly towards longer wavelengths in freshwater compared with the ancestral marine form. Laboratory rearing suggests that this shift is largely genetically based. Using a new metric, we found that the magnitude of shift in spectral sensitivity in each population corresponds strongly to the transition in the availability of different wavelengths of light between the marine and lake environments. We also found evidence of local adaptation by sympatric benthic and limnetic ecotypes to different light environments within lakes. Our findings indicate rapid parallel evolution of the visual system to altered light conditions. The changes have not, however, yielded a close matching of spectrum-wide sensitivity to wavelength availability, for reasons we discuss.

scholarly journals The evolution of red colour vision is linked to coordinated rhodopsin tuning in lycaenid butterflies

2020 ◽  
Author(s):  
Marjorie A. Liénard ◽  
Gary D. Bernard ◽  
Andrew A. Allen ◽  
Jean-Marc Lassance ◽  
Siliang Song ◽  
...  
Keyword(s):  
Visual System ◽  
Spectral Sensitivity ◽  
Colour Vision ◽  
Bathochromic Shift ◽  
Red Light ◽  
Opsin Gene ◽  
Spectral Energy ◽  
Functional Changes

AbstractColour vision is largely mediated by changes in number, expression, and spectral properties of rhodopsins, but the genetic mechanisms underlying adaptive shifts in spectral sensitivity remain largely unexplored. Using in vivo photochemistry, optophysiology, and in vitro functional assays, we link variation in eye spectral sensitivity at long wavelengths to species-specific absorbance spectra for LW opsins in lycaenid butterflies. In addition to loci specifying an ancestral green-absorbing rhodopsin with maximum spectral sensitivity (λmax) at 520-530 nm in Callophrys sheridanii and Celastrina ladon, we find a novel form of red-shifted LW rhodopsin at λmax = 565-570 nm in Arhopala japonica and Eumaeus atala. Furthermore, we show that Ca. sheridanii and Ce. ladon exhibit a smaller bathochromic shift at BRh2 (480-489 nm), and with the ancestral LW rhodopsin, cannot perceive visible red light beyond 600 nm. In contrast, molecular variation at the LW opsin in A. japonica and E. atala is coordinated with tuning of the blue opsin that also shifts sensitivity to longer wavelengths enabling colour discrimination up to 617 nm. We then use E. atala as a model to examine the interplay between red and blue spectral sensitivity. Owing to blue duplicate expression, the spatial distribution of opsin mRNAs within an ommatidium defines an expanded retinal stochastic mosaic of at least six opsin-based photoreceptor classes. Our mutagenesis in vitro assays with BRh1 (λmax = 435 nm) chimeric blue rhodopsins reveal four main residues contributing to the 65 nm bathochromic shift towards BRh2 (λmax = 500 nm). Adaptations in this four-opsin visual system are relevant for discrimination of conspecific reflectance spectra in E. atala. Together, these findings illustrate how functional changes at multiple rhodopsins contribute to the evolution of a broader spectral sensitivity and adaptation in visual performance.Significance StatementRhodopsins are photosensitive protein molecules that absorb specific wavelengths of incoming light and convey colour information in the visual system. We show that molecular evolution in a green insect opsin gene resulted in a shift in its maximal absorbance peak, enabling some lycaenid butterflies to use spectral energy of longer wavelengths (LW) to discriminate colours in the red spectrum better than relatives bearing ancestral green LW rhodopsins. Lycaenids also evolved a duplicate blue opsin gene, and we illustrate an example where species equipped with red LW rhodopsins shifted their blue sensitivity peak to longer wavelengths due to changes in several blue-tuning residues that have evolved repeatedly in different insect lineages. We demonstrate how changes at multiple vision genes in the insect eye effectively create a coordinated mechanism expanding spectral sensitivity for visually guided behaviours such as selecting host plants and mates.

scholarly journals Evolutionary analyses of visual opsin genes in anurans reveals diversity and positive selection suggestive of functional adaptation to distinct light environments

2021 ◽  
Author(s):  
Ryan K Schott ◽  
Leah Perez ◽  
Matthew A Kwiatkowski ◽  
Vance Imhoff ◽  
Jennifer M Gumm
Keyword(s):  
Positive Selection ◽  
Spectral Sensitivity ◽  
Life Histories ◽  
Visual Pigments ◽  
Molecular Techniques ◽  
Functional Adaptation ◽  
Opsin Gene ◽  
Visual Systems ◽  
Opsin Genes ◽  
Dim Light

Among major vertebrate groups, anurans (frogs and toads) are understudied with regards to their visual systems and little is known about variation among species that differ in ecology. We sampled North American anurans representing diverse evolutionary and life histories that likely possess visual systems adapted to meet different ecological needs. Using standard molecular techniques, visual opsin genes, which encode the protein component of visual pigments, were obtained from anuran retinas. Additionally, we extracted the visual opsins from publicly available genome and transcriptome assemblies, further increasing the phylogenetic and ecological diversity of our dataset. We found that anurans consistently express four visual opsin genes (RH1, LWS, SWS1, and SWS2, but not RH2) even though reported photoreceptor complements vary widely among species. We found the first evidence of visual opsin duplication in an amphibian with the duplication of the LWS gene in the African bullfrog, which had distinct LWS copies on the sex chromosomes. The proteins encoded by these genes showed considerable sequence variation among species, including at sites known to shift the spectral sensitivity of visual pigments in other vertebrates and thus mediate dim-light and color vision. Using molecular evolutionary analyses of selection (dN/dS) we found significant evidence for positive selection at a subset of sites in the dim-light rod opsin gene RH1 and the long wavelength sensitive cone opsin gene LWS. The function of sites inferred to be under positive selection are largely unknown, but a few are likely to affect spectral sensitivity and other visual pigment functions based on proximity to previously identified sites in other vertebrates. The observed variation cannot fully be explained by evolutionary relationships among species alone. Taken together, our results suggest that other ecological factors, such as habitat and life history, as well as behaviour, may be driving changes to anuran visual systems.

Expression of opsin mRNA in normal and vitamin A deficient retinas of the sphingid moth Manduca sexta

1996 ◽  
Vol 13 (2) ◽  
pp. 353-358 ◽  
Author(s):  
Michael R. Chase ◽  
Ruth R. Bennett ◽  
Richard H. White
Keyword(s):  
Polymerase Chain Reaction ◽  
Amino Acid ◽  
Vitamin A ◽  
Amino Acid Sequence ◽  
Manduca Sexta ◽  
Opsin Gene ◽  
Chain Reaction ◽  
Northern Blots ◽  
Polymerase Chain ◽  
Cdna Fragments

AbstractTwo distinct opsin-encoding cDNAs, designated MANOP1 and MANOP2, were isolated as 3′ fragments from the sphingid moth Manduca sexta. They were obtained by reverse transcription of retinal RNA and amplification with the polymerase chain reaction (PCR) using a degenerate primer designed to an amino-acid sequence conserved in arthropod opsins. The cDNA fragments labelled bands at approximately 1.8 kb on Northern blots of retinal RNA extracts. Levels of opsin message were compared in retinas from normal moths, whose diets were fortified with carotenoid precursors of the Manduca rhodopsin chromophore, 3-hydroxyretinal, and those reared on carotenoid/retinoid (vitamin A) deficient diets. The chromophore-depleted retinas contained more opsin mRNA; this was particularly true for MANOP2. Thus, the chromophore is not required for opsin gene transcription in Manduca.

The staining pattern of the tropomyosin sequence is displayed in a new paracrystal

1986 ◽  
Vol 44 ◽  
pp. 150-151
Author(s):  
M.K. Lamvik ◽  
L.L. Klatt
Keyword(s):  
Amino Acid ◽  
Amino Acid Sequence ◽  
Staining Pattern ◽  
Banding Patterns ◽  
Mass Thickness ◽  
New Form

Tropomyosin paracrystals have been used extensively as test specimens and magnification standards due to their clear periodic banding patterns. The paracrystal type discovered by Ohtsuki1 has been of particular interest as a test of unstained specimens because of alternating bands that differ by 50% in mass thickness. While producing specimens of this type, we came across a new paracrystal form. Since this new form displays aligned tropomyosin molecules without the overlaps that are characteristic of the Ohtsuki-type paracrystal, it presents a staining pattern that corresponds to the amino acid sequence of the molecule.

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