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Evolution of the cichlid visual palette through ontogenetic subfunctionalization of the opsin gene arrays.
TLDR
Subfunctionalization through differential ontogenetic expression may be a key mechanism for preservation of opsin genes and provide a palette from which selection creates the diverse visual sensitivities found among the cichlid species of the lacustrine adaptive radiations. Expand
Spectral tuning of avian violet- and ultraviolet-sensitive visual pigments.
TLDR
This paper presents the sequences of two pigments isolated from Humbolt penguin and pigeon with intermediate lambda(max) values of 403 and 409 nm, respectively and identifies five amino acid sites that show a pattern of substitution between species that is consistent with differences inlambda(max). Expand
Shedding new light on opsin evolution
TLDR
This work uses an extensive phylogeny of currently known opsin sequence diversity as a foundation for examining the evolutionary distributions of key functional features within the opsin clade, and illustrates the lability of opsin protein-expression patterns, site-specific functionality and G-protein binding interactions. Expand
The molecular mechanism for the spectral shifts between vertebrate ultraviolet- and violet-sensitive cone visual pigments.
TLDR
Using site-directed mutagenesis of goldfish UVS opsin, it is shown that a Phe-86-->Tyr substitution is sufficient by itself to shift the lambda(max) of the goldfish pigment from a wild-type value of 360 nm to around 420 nm, and the reverse substitution of Tyr-86-Phe into bovine VS opsin produces a similar shift in the opposite direction. Expand
Spectral tuning and evolution of primate short-wavelength-sensitive visual pigments
TLDR
It is concluded that the tuning of VS pigments in primates depends on Pro93, not Tyr86 as in other mammals, and phylogenetic analysis indicates that substitutions at site 86 have occurred at least five times in primate evolution. Expand
The visual pigments of the bottlenose dolphin (Tursiops truncatus).
TLDR
Although the dolphin possesses a gene homologous to other mammalian short-wavelength sensitive (SWS) opsins, it is not expressed in vivo and has accumulated a number of deletions, including a frame-shift mutation at nucleotide position 31, and therefore lacks the common dichromatic form of color vision typical of most terrestrial mammals. Expand
Photochemistry of retinal chromophore in mouse melanopsin
TLDR
Results indicate that even if melanopsin functions as a bistable photopigment with photo-regenerative activity native melanops in vivo must also use some other light-independent retinoid regeneration mechanism to return to the dark state, where all of the retinal is observed to be in the 11-cis form. Expand
Melanopsin forms a functional short-wavelength photopigment.
TLDR
The experiments constitute the first direct demonstration that melanopsin forms a photopigment capable of activating a G-protein, but its spectral properties are not consistent with the action spectrum for circadian entrainment. Expand
Spectral-tuning mechanisms of marine mammal rhodopsins and correlations with foraging depth
TLDR
The objective of this study was to investigate the molecular basis for changes in the spectral sensitivity of rod visual pigments from seven distantly related marine mammals and show a relationship between blue-shifted rhodopsins, deep-diving foraging behavior, and the substitutions 83Asn and 292Ser. Expand
Mechanism of activation and inactivation of opsin: role of Glu113 and Lys296.
TLDR
P pH-rate profiles for the rhodopsin-catalyzed exchange of GTPgS for GDP on transducin are established and it is evident that at least two ionizable groups in addition to Lys296 and Glu113 control the formation of the active opsin state. Expand
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