In vertebrate photoreceptors, light induces hydrolysis of cGMP by activating phosphodiesterase (PDE), which results in closure the cGMP-activated cation channel. During adaptation, cytoplasmic Ca2+ concentration decreases, and this decrease is one underlying mechanisms adaptation. Sensitivity-modulating protein (S-modulin) a Ca(2+)-binding involved adaptation frog rods; it regulates both sensitivity PDE lifetime activated controlling rhodopsin phosphorylation Ca(2+)-dependent manner....

The gene encoding photoactive yellow protein (PYP) was isolated from Ectothiorhodospira halophila, and a high-level expression system for PYP constructed in Escherichia coli. molecular weight the absorption spectrum of expressed E. coli were identical with those native halophila. amino acid residues which might interact chromophore (Tyr42, Glu46, Thr50, Arg52, Cys69) mutated by site-directed mutagenesis spectra these mutants examined to study chromophore/protein interaction PYP. former three...

Attenuated total reflection infrared (ATR-IR) spectroscopy was performed on glycerol/water solutions in order to gain a better understanding of the strong hydrogen bonding glycerol as humectant. The OH stretching band after eliminating contribution decomposed using three Gaussian components. With increasing concentrations up 50 volume %, decrease 3428 cm−1 component (middle H-bond component) and increase 3562 (longer suggested breaking H bonds among water molecules. On other hand, 3242...

Two kinds of retinal cDNA fragments (OlGRK‐R and ‐C) encoding the putative G‐protein‐coupled receptor kinases (GRKs) were isolated from medaka, Oryzias latipes . OlGRK‐R appears to be closely related rhodopsin kinase (RK) found in outer segments mammalian photoreceptors, but deduced amino acid sequence OlGRK‐C shows less than 50% identity those GRKs known date, suggesting that is a novel GRK subtype (GRK7). The mRNA detectable rods, all four types cone photoreceptor. C‐terminal has consensus...

Photoactive yellow protein (PYP) belongs to the novel group of eubacterial photoreceptor proteins. To fully understand its light signal transduction mechanisms, elucidation intramolecular pathway internal proton is indispensable because it closely correlates with changes in hydrogen-bonding network, which likely induce conformational changes. For this purpose, vibrational modes PYP and photoproduct were studied by Fourier transform infrared spectroscopy at −40 °C. The characteristic for...

Aureochrome-1 (AUREO1) is a blue light (BL) receptor that mediates the branching response in stramenopile alga, Vaucheria frigida. AUREO1 contains basic leucine zipper (bZIP) domain central region and light-oxygen-voltage sensing (LOV) at C terminus, has been suggested to function as light-regulated transcription factor. We have previously reported preparations of recombinant contained complete coding sequence (full-length, FL) N-terminal truncated protein (ZL) containing bZIP LOV domains,...

ABSTRACT The primary structures of two opsins from the brachyuran crab Hemigrapsus sanguineus were deduced cDNA nucleotide sequences. Both proteins composed 377 amino acid residues and included highly conserved in visual pigments other species, 75 % identical to each other. distribution opsin transcripts compound eye, determined by situ hybridization, suggested that mRNAs expressed simultaneously all seven retinular cells (R1–R7) forming main rhabdom ommatidium. Two different may be present...

Aureochrome-1 (AUREO1) is a blue light (BL) receptor that mediates the branching response in stramenopile alga, Vaucheria frigida. AUREO1 harbors basic leucine zipper (bZIP) domain at N-terminus and light–oxygen–voltage-sensing (LOV) within C-terminal region, has been suggested to function as light-regulated transcription factor. To understand molecular mechanism of AUREO1, we have prepared three recombinant proteins: full-length (FL), an N-terminal truncated construct containing bZIP LOV...

Significance Anurans are unique in possessing two types of rod photoreceptor cells, red and green rods. Red rods express rhodopsin, whereas blue-sensitive cone visual pigment. Rhodopsin exhibits a low rate thermal isomerization the retinal chromophore, which enables to detect photons with extremely high signal-to-noise for scotopic vision. Here, we show that anuran pigments acquired rhodopsin-like property through single amino acid mutation at position 47 evolutionary process from other...

Aureochrome-1 (AUREO1) is a blue light (BL) receptor responsible for the BL-induced blanching of stramenopile alga, Vaucheria frigida. The AUREO1 protein contains central basic region/leucine zipper (bZIP) domain, and C-terminal light-oxygen-voltage-sensing (LOV) domain. BL induces dimerization monomeric AUREO1, which subsequently increases affinity this transcription factor its target DNA [Hisatomi, O., et al. (2014) J. Biol. Chem. 289, 17379-17391]. We constructed synthetic gene encoding...

Aureochrome (Aureo) is a recently discovered blue light sensor protein initially from Vaucheria frigida, in which it controls light-dependent branch formation and/or development of sex organ by change the affinity for DNA. Although photochemical reactions Aureo-LOV (LOV C-terminal light-oxygen-voltage domain) and N-terminal truncated construct containing bZIP (N-terminal basic leucine zipper LOV domain have previously been reported, reaction kinetics DNA never elucidated. The Aureo where...

Summary The ability to increase the synthesis or vary distribution of pigment in response light is an important feature many cells. Unlike other light‐sensitive cells, erythrophores Nile tilapia change direction migration depending on peak wavelength incident light: near 365, 400 600 nm induces aggregation, while dispersion occurs at 500 nm. How these phenomena are achieved currently unknown. In present study, phototransduction involved caused by aggregation was examined, using pertussis...

To investigate the roles of amino acid residues around chromophore in photoactive yellow protein (PYP), new mutants, Y42A, E46A, and T50A were prepared. Their spectroscopic properties compared with those wild-type, Y42F, E46Q, T50V, R52Q, E46Q/T50V, which previously prepared specified. The absorption maxima observed at 438, 469, 454 nm, respectively. results pH titration for demonstrated that PYP mutant, like was protonated bleached under acidic conditions. red-shifts mutants tended toward a...

In frog retina there are special rod photoreceptor cells (‘green rods’) with physiological properties similar to those of typical vertebrate rods (‘red rods’). A cDNA fragment encoding the putative green visual pigment was isolated from a retinal library bullfrog, Rana catesbeiana . Its deduced amino acid sequence has more than 65% identity blue‐sensitive cone pigments such as chicken blue and goldfish blue. Antisera raised against its C‐terminal recognized rods. It is concluded that...

A frog retinal protein named s26 is a 26-kDa found during purification of S-modulin in retina (Kawamura, S. (1992) Photochem. Photobiol. 56, 1173-1180). To identify its role retina, first was purified to nearly homogeneity with three chromatographical steps. Based on the partial amino acid sequences proteolysed fragments s26, we isolated cDNAs that encode s26. The analysis sequence revealed an S-modulin-like protein, while it shows higher homology visinin. Visinin Ca2+-binding reported be...