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Gühmann M, Porter ML, Bok MJ. The Gluopsins: Opsins without the Retinal Binding Lysine. Cells 2022; 11:cells11152441. [PMID: 35954284 PMCID: PMC9368030 DOI: 10.3390/cells11152441] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 07/23/2022] [Accepted: 07/28/2022] [Indexed: 12/14/2022] Open
Abstract
Opsins allow us to see. They are G-protein-coupled receptors and bind as ligand retinal, which is bound covalently to a lysine in the seventh transmembrane domain. This makes opsins light-sensitive. The lysine is so conserved that it is used to define a sequence as an opsin and thus phylogenetic opsin reconstructions discard any sequence without it. However, recently, opsins were found that function not only as photoreceptors but also as chemoreceptors. For chemoreception, the lysine is not needed. Therefore, we wondered: Do opsins exists that have lost this lysine during evolution? To find such opsins, we built an automatic pipeline for reconstructing a large-scale opsin phylogeny. The pipeline compiles and aligns sequences from public sources, reconstructs the phylogeny, prunes rogue sequences, and visualizes the resulting tree. Our final opsin phylogeny is the largest to date with 4956 opsins. Among them is a clade of 33 opsins that have the lysine replaced by glutamic acid. Thus, we call them gluopsins. The gluopsins are mainly dragonfly and butterfly opsins, closely related to the RGR-opsins and the retinochromes. Like those, they have a derived NPxxY motif. However, what their particular function is, remains to be seen.
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Affiliation(s)
- Martin Gühmann
- School of Biological Sciences, University of Bristol, Bristol BS8 1TQ, UK
- Correspondence:
| | - Megan L. Porter
- Department of Biology, University of Hawai’i at Mānoa, Honolulu, HI 96822, USA
| | - Michael J. Bok
- Lund Vision Group, Department of Biology, University of Lund, 223 62 Lund, Sweden
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2
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Frederiksen R, Nymark S, Kolesnikov AV, Berry JD, Adler L, Koutalos Y, Kefalov VJ, Cornwall MC. Rhodopsin kinase and arrestin binding control the decay of photoactivated rhodopsin and dark adaptation of mouse rods. J Gen Physiol 2017; 148:1-11. [PMID: 27353443 PMCID: PMC4924931 DOI: 10.1085/jgp.201511538] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Accepted: 06/06/2016] [Indexed: 12/22/2022] Open
Abstract
G-protein receptor kinase and arrestin 1 are required for inactivation of photoactivated vertebrate rhodopsin. Frederiksen et al. show that they additionally regulate the subsequent decay of inactive rhodopsin into opsin and all-trans retinal and therefore dark adaptation. Photoactivation of vertebrate rhodopsin converts it to the physiologically active Meta II (R*) state, which triggers the rod light response. Meta II is rapidly inactivated by the phosphorylation of C-terminal serine and threonine residues by G-protein receptor kinase (Grk1) and subsequent binding of arrestin 1 (Arr1). Meta II exists in equilibrium with the more stable inactive form of rhodopsin, Meta III. Dark adaptation of rods requires the complete thermal decay of Meta II/Meta III into opsin and all-trans retinal and the subsequent regeneration of rhodopsin with 11-cis retinal chromophore. In this study, we examine the regulation of Meta III decay by Grk1 and Arr1 in intact mouse rods and their effect on rod dark adaptation. We measure the rates of Meta III decay in isolated retinas of wild-type (WT), Grk1-deficient (Grk1−/−), Arr1-deficient (Arr1−/−), and Arr1-overexpressing (Arr1ox) mice. We find that in WT mouse rods, Meta III peaks ∼6 min after rhodopsin activation and decays with a time constant (τ) of 17 min. Meta III decay slows in Arr1−/− rods (τ of ∼27 min), whereas it accelerates in Arr1ox rods (τ of ∼8 min) and Grk1−/− rods (τ of ∼13 min). In all cases, regeneration of rhodopsin with exogenous 11-cis retinal is rate limited by the decay of Meta III. Notably, the kinetics of rod dark adaptation in vivo is also modulated by the levels of Arr1 and Grk1. We conclude that, in addition to their well-established roles in Meta II inactivation, Grk1 and Arr1 can modulate the kinetics of Meta III decay and rod dark adaptation in vivo.
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Affiliation(s)
- Rikard Frederiksen
- Department of Physiology and Biophysics, Boston University School of Medicine, Boston, MA 02118
| | - Soile Nymark
- Department of Electronics and Communications Engineering, BioMediTech, Tampere University of Technology, 33720 Tampere, Finland
| | - Alexander V Kolesnikov
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO 63110
| | - Justin D Berry
- Department of Physiology and Biophysics, Boston University School of Medicine, Boston, MA 02118
| | - Leopold Adler
- Department of Ophthalmology, Medical University of South Carolina, Charleston, SC 29425
| | - Yiannis Koutalos
- Department of Ophthalmology, Medical University of South Carolina, Charleston, SC 29425
| | - Vladimir J Kefalov
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO 63110
| | - M Carter Cornwall
- Department of Physiology and Biophysics, Boston University School of Medicine, Boston, MA 02118
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Maeda T, Dong Z, Jin H, Sawada O, Gao S, Utkhede D, Monk W, Palczewska G, Palczewski K. QLT091001, a 9-cis-retinal analog, is well-tolerated by retinas of mice with impaired visual cycles. Invest Ophthalmol Vis Sci 2013; 54:455-66. [PMID: 23249702 DOI: 10.1167/iovs.12-11152] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
PURPOSE Investigate whether retinas of mice with impaired retinal cycles exposed to light or kept in the dark tolerate prolonged high-dose administration of QLT091001, which contains as an active ingredient, the 9-cis-retinal precursor, 9-cis-retinyl acetate. METHODS Four- to six-week-old Lrat(-/-) and Rpe65(-/-) mice (n = 126) as well as crossbred Gnat1(-/-) mice lacking rod phototransduction (n = 110) were gavaged weekly for 6 months with 50 mg/kg QLT091001, either after being kept in the dark or after light bleaching for 30 min/wk followed by maintenance in a 12-hour light ≤ 10 lux)/12-hour dark cycle. Retinal health was monitored by spectral-domain optical coherent tomography (SD-OCT) and scanning laser ophthalmoscopy (SLO) every other month and histological, biochemical, and visual functional analyses were performed at the end of the experiment. Two-photon microscopy (TPM) was used to observe retinoid-containing retinosome structures in the RPE. RESULTS Retinal thickness and morphology examined by SD-OCT were well maintained in all strains treated with QLT091001. No significant increases of fundus autofluorescence were detected by SLO imaging of any strain. Accumulation of all-trans-retinyl esters varied with genetic background, types of administered compounds and lighting conditions but retinal health was not compromised. TPM imaging clearly revealed maintenance of retinosomes in the RPE of all mouse strains tested. CONCLUSIONS Retinas of Lrat(-/-), Rpe65(-/-), and crossbred Gnat1(-/-) mice tolerated prolonged high-dose QLT091001 treatment well.
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Affiliation(s)
- Tadao Maeda
- Department of Ophthalmology, School of Medicine, Case Western Reserve University, Cleveland, Ohio 44106, USA
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Gao SQ, Maeda T, Okano K, Palczewski K. A microparticle/hydrogel combination drug-delivery system for sustained release of retinoids. Invest Ophthalmol Vis Sci 2012; 53:6314-23. [PMID: 22918645 PMCID: PMC3465014 DOI: 10.1167/iovs.12-10279] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2012] [Revised: 07/18/2012] [Accepted: 08/20/2012] [Indexed: 11/24/2022] Open
Abstract
PURPOSE To design and develop a drug-delivery system containing a combination of poly(D,L-lactide-co-glycolide) (PLGA) microparticles and alginate hydrogel for sustained release of retinoids to treat retinal blinding diseases that result from an inadequate supply of retinol and generation of 11-cis-retinal. METHODS To study drug release in vivo, either the drug-loaded microparticle-hydrogel combination was injected subcutaneously or drug-loaded microparticles were injected intravitreally into Lrat(-/-) mice. Orally administered 9-cis-retinoids were used for comparison and drug concentrations in plasma were determined by HPLC. Electroretinography (ERG) and both chemical and histologic analyses were used to evaluate drug effects on visual function and morphology. RESULTS Lrat(-/-) mice demonstrated sustained drug release from the microparticle/hydrogel combination that lasted 4 weeks after subcutaneous injection. Drug concentrations in plasma of the control group treated with the same oral dose rose to higher levels for 6-7 hours but then dropped markedly by 24 hours. Significantly increased ERG responses and a markedly improved retinal pigmented epithelium (RPE)-rod outer segment (ROS) interface were observed after subcutaneous injection of the drug-loaded delivery combination. Intravitreal injection of just 2% of the systemic dose of drug-loaded microparticles provided comparable therapeutic efficacy. CONCLUSIONS Sustained release of therapeutic levels of 9-cis-retinoids was achieved in Lrat(-/-) mice by subcutaneous injection in a microparticle/hydrogel drug-delivery system. Both subcutaneous and intravitreal injections of drug-loaded microparticles into Lrat(-/-) mice improved visual function and retinal structure.
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Affiliation(s)
| | - Tadao Maeda
- Ophthalmology, School of Medicine, Case Western Reserve University, Cleveland, Ohio
| | - Kiichiro Okano
- Ophthalmology, School of Medicine, Case Western Reserve University, Cleveland, Ohio
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Chung WC, Nanbu S, Ishida T. QM/MM Trajectory Surface Hopping Approach to Photoisomerization of Rhodopsin and Isorhodopsin: The Origin of Faster and More Efficient Isomerization for Rhodopsin. J Phys Chem B 2012; 116:8009-23. [DOI: 10.1021/jp212378u] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Wilfredo Credo Chung
- Fukui Institute
for Fundamental Chemistry, Kyoto University, 34-4, Takano-nishihirakicho, Sakyo-ku, Kyoto 606-8103, Japan
| | - Shinkoh Nanbu
- Department of Materials
and Life Sciences, Faculty of Science and Engineering, Sophia University, Kioicho, Chiyoda-ku, Tokyo 102-8554,
Japan
| | - Toshimasa Ishida
- Fukui Institute
for Fundamental Chemistry, Kyoto University, 34-4, Takano-nishihirakicho, Sakyo-ku, Kyoto 606-8103, Japan
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Lanska DJ. Chapter 29: historical aspects of the major neurological vitamin deficiency disorders: overview and fat-soluble vitamin A. HANDBOOK OF CLINICAL NEUROLOGY 2009; 95:435-44. [PMID: 19892132 DOI: 10.1016/s0072-9752(08)02129-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The vitamine doctrine: Although diseases resulting from vitamin deficiencies have been known for millennia, such disorders were generally attributed to toxic or infectious causes until the "vitamin doctrine" was developed in the early 20th century. In the late-19th century, a physiologically complete diet was believed to require only sufficient proteins, carbohydrates, fats, inorganic salts, and water. From 1880-1912, Lunin, Pekelharing, and Hopkins found that animals fed purified mixtures of known food components failed to grow or even lost weight and died, unless the diet was supplemented with small amounts of milk, suggesting that "accessory food factors" are required in trace amounts for normal growth. By this time, Funk suggested that deficiencies of trace dietary factors, which he labeled "vitamines" on the mistaken notion that they were "vital amines," were responsible for such diseases as beriberi, scurvy, rickets, and pellagra. Vitamin A deficiency eye disease: Night blindness was recognized by the ancient Egyptians and Greeks, and many authorities from Galen onward advocated liver as a curative. Outbreaks of night blindness were linked to nutritional causes in the 18th and 19th centuries by von Bergen, Schwarz, and others. Corneal ulceration was reported in 1817 by Magendie among vitamin A-deficient dogs fed for several weeks on a diet limited to sugar and water, although he erroneously attributed this to a deficiency of dietary nitrogen (i.e. protein). Subsequently, corneal epithelial defects, often in association with night blindness, were recognized in malnourished individuals subsisting on diets now recognizable as deficient in vitamin A by Budd, Livingstone, von Hubbenet, Bitot, Mori, Ishihari, and others. During World War I, Bloch conducted a controlled clinical trial of different diets among malnourished Danish children with night blindness and keratomalacia and concluded that whole milk, butter, and cod-liver oil contain a fat-soluble substance that protects against xerophthalmia. Early retinal photochemistry: In the 1870s, Boll found that light causes bleaching of the retinal pigment, and suggested that the outer segments of the rods contain a substance that conveys an impression of light to the brain by a photochemical process. Shortly thereafter, Kühne demonstrated that the bleaching process depends upon light, and was reversible if the retinal pigment epithelium was intact. Kühne proposed an "optochemical hypothesis," a prescient concept of photochemical transduction, attributing vision to a photochemical change in visual purple (rhodopsin) with resulting chemical products stimulating the visual cells and thereby conveying a visual image. Vitamin A: In 1913, Ishihara proposed that a "fatty substance" in blood is necessary for synthesis of both rhodopsin and the surface layer of the cornea, and that night blindness and keratomalacia develop when this substance is deficient. That year McCollum and Davis (and almost simultaneously Mendel and Osborne) discovered a fat-soluble accessory food factor (later called "fat-soluble A") distinct from the water-soluble anti-beriberi factor (later called "fat-soluble B"). By 1922 McCollum and colleagues distinguished two vitamins within the fat-soluble fraction, later named vitamins A and D. In 1925 Fridericia and Holm directly linked vitamin A to night blindness in animal experiments using rats, and in 1929 Holm demonstrated the presence of vitamin A in retinal tissue. In the 1930s, Moore, Karrer, Wald, and others established the provitamin role of beta-carotene. Karrer and colleagues isolated beta-carotene (the main dietary precursor of vitamin A) and retinol (vitamin A), and determined their chemical structures. In 1947, Isler and colleagues completed the full chemical synthesis of vitamin A. Modern retinal photochemistry: Beginning in the 1930s, Wald and colleagues greatly elaborated the photochemistry of vision, with the discovery of the visual cycle of vitamin A, demonstration that rhodopsin is decomposed by light into retinal (the aldehyde form of vitamin A) and a protein (opsin), elaboration of the enzymatic conversions of various elements in the rhodopsin system, and discovery that the rhodopsin system is dependent on a photoisomerization of retinal. In 1942, Hecht and colleagues demonstrated that a single photon could trigger excitation in a rod. In 1965, Wald suggested that a large chemical amplification was necessary for this degree of light sensitivity, likely by a cascade of enzymatic reactions. Later studies elaborated this cascade and found that an intermediary in the photoisomerization of retinal interacts with transducin, a G-protein, to activate phosphodiesterases that control cyclic GMP levels, which in turn modulate the release of neurotransmitter from the rod cell. Public health: Although the availability of vitamin A through food fortification and medicinal supplements virtually eliminated ocular vitamin A deficiency from developed countries by the second half of the 20th century, vitamin A deficiency remains a serious problem in developing countries as indicated by global surveys beginning in the 1960s. Millions of children were shown to be vitamin A deficient, with resultant blindness, increased susceptibility to infection, and increased childhood mortality. Beginning in the 1960s, intervention trials showed that vitamin A deficiency disorders could be prevented in developing countries with periodic vitamin A dosing, and in the 1980s and 1990s, large randomized, double-blind, placebo-controlled clinical trials demonstrated the marked efficacy of vitamin A supplementation in reducing childhood mortality.
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Affiliation(s)
- Douglas J Lanska
- Department of Neurology, Veterans Affairs Medical Center, Tomah, WI 54660, USA.
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7
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López CS, Álvarez R, Domínguez M, Faza ON, de Lera ÁR. Complex Thermal Behavior of 11-cis-Retinal, the Ligand of the Visual Pigments. J Org Chem 2008; 74:1007-13. [DOI: 10.1021/jo801899k] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Carlos Silva López
- Departamento de Química Orgánica, Facultade de Química, Universidade de Vigo, Lagoas Marcosende, E-36310, Vigo, Spain
| | - Rosana Álvarez
- Departamento de Química Orgánica, Facultade de Química, Universidade de Vigo, Lagoas Marcosende, E-36310, Vigo, Spain
| | - Marta Domínguez
- Departamento de Química Orgánica, Facultade de Química, Universidade de Vigo, Lagoas Marcosende, E-36310, Vigo, Spain
| | - Olalla Nieto Faza
- Departamento de Química Orgánica, Facultade de Química, Universidade de Vigo, Lagoas Marcosende, E-36310, Vigo, Spain
| | - Ángel R. de Lera
- Departamento de Química Orgánica, Facultade de Química, Universidade de Vigo, Lagoas Marcosende, E-36310, Vigo, Spain
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8
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Das PK, Becker RS. SPECTROSCOPY OF POLYENES-IV. ABSORPTION AND EMISSION SPECTRAL PROPERTIES OF POLYENE ALCOHOLS RELATED TO RETINOL AS HOMOLOGUES. Photochem Photobiol 2008. [DOI: 10.1111/j.1751-1097.1980.tb04051.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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10
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11
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Alvarez R, Domínguez B, de Lera AR. AN EXPEDIENT STEREOCONTROLLED SYNTHESIS OF 7-CIS-RETINOIDS. SYNTHETIC COMMUN 2006. [DOI: 10.1081/scc-100104430] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Rosana Alvarez
- a Departamento de Química Orgánica , Universidade de Vigo , Vigo , 36200 , Spain
| | - Beatriz Domínguez
- a Departamento de Química Orgánica , Universidade de Vigo , Vigo , 36200 , Spain
| | - Angel R. de Lera
- b Departamento de Química Orgánica , Universidade de Vigo , Vigo , 36200 , Spain
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12
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Oroshnik W, Brown PK, Hubbard R, Wald G. HINDERED CIS ISOMERS OF VITAMIN A AND RETINENE: THE STRUCTURE OF THE NEO-b ISOMER. Proc Natl Acad Sci U S A 2006; 42:578-80. [PMID: 16589909 PMCID: PMC534254 DOI: 10.1073/pnas.42.9.578] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- W Oroshnik
- ORTHO RESEARCH FOUNDATION, RARITAN, NEW JERSEY
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13
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Schwieter U, Saucy G, Montavon M, v. Planta C, Rüegg R, Isler O. Synthesen in der Vitamin-A 2-Reihe. 1. Mitteilung. Die Darstellung von kristallinem all- trans-Vitamin A 2und von zwei Isomeren mit sterischer Hinderung. Helv Chim Acta 2004. [DOI: 10.1002/hlca.19620450215] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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14
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Trehan A, Mirzadegan T, Liu R. The doubly hindered 7,11-dicis, 7,9,11-tricis, 7,11,13-tricis and all-cis isomers of retinonitrile and retinal. Tetrahedron 1990. [DOI: 10.1016/s0040-4020(01)90512-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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15
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16
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Asato AE, Denny M, Matsumoto H, Mirzadegan T, Ripka WC, Crescitelli F, Liu RS. Study of the shape of the binding site of bovine opsin using 10-substituted retinal isomers. Biochemistry 1986; 25:7021-6. [PMID: 2948554 DOI: 10.1021/bi00370a039] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The 9-cis, 11-cis, 13-cis, and all-trans isomers of 10-fluoro-, 10-chloro-, 10-methyl-, and 10-ethylretinals have been prepared and characterized. Results of their interaction with bovine opsin are reported. The data have been analyzed in terms of the conformational properties of the retinal isomers and their steric compatibility with the binding site as defined by the two-dimensional map disclosed earlier. The need to expand the active zone and previously undetected restrictions in the third dimension are noted.
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van Kuijk FJ, Handelman GJ, Dratz EA. Rapid analysis of the major classes of retinoids by step gradient reversed-phase high-performance liquid chromatography using retinal (O-ethyl) oxime derivatives. J Chromatogr A 1985; 348:241-51. [PMID: 4086639 DOI: 10.1016/s0021-9673(01)92458-6] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
A rapid step-gradient reversed-phase high-performance liquid chromatography (HPLC) method is presented for analysis of the major classes of retinoids in tissues. Retinal was converted into a new derivative, retinal (O-ethyl) oxime, since the standard derivative, retinaloxime, co-elutes with retinol on reversed-phase HPLC. The most abundant naturally occurring retinyl esters, retinyl palmitate and retinyl stearate, were eluted within 12 min to complete the separation. Retinoids were extracted in the presence of an antioxidant, butylated hydroxytoluene, and a lipid carrier, cholesterol. Recoveries of 98-100% were obtained from tissue samples by internal addition for the retinoids tested (retinol, retinal and retinyl palmitate); and the absolute recovery of endogenous retinal from rat eyecups was confirmed by spectrophotometric measurements of rhodopsin. Extraction was carried out in an air atmosphere and under subdued incandescent light rather than requiring inert atmosphere and safe-light conditions used in most methods. Cis-trans isomers were not separated under the reversed-phase HPLC conditions employed. Quantitation was carried out using retinyl acetate as internal standard and the day to day precision was better than 3.5%. A sensitivity of about 1 ng is obtained for all retinoids using absorbance monitoring at 325 nm and a C18 5 micrometers column with 12% reversed-phase loading. The tocopherols can also be separated and detected simultaneously with similar sensitivity by this method using a fluorescence detector in series [G. J. Handelman, L. J. Machlin, K. Fitch, J. J. Weiter and E. A. Dratz, J. Nutr., 115 (1985) 807].
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18
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DAS PARITOSHK, BECKER RALPHS. TWENTY-TWO CARBON HOMOLOGUE OF 11-CIS RETINAL. PHOTOPHYSICAL AND PHOTOCHEMICAL PROPERTIES. Photochem Photobiol 1984. [DOI: 10.1111/j.1751-1097.1984.tb08183.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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19
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Robert LS, Matsumoto H, Kini A, Asato AE, Denny M, Kropf A, DeGrip WJ. Seven new hindered isomeric rhodopsins. Tetrahedron 1984. [DOI: 10.1016/0040-4020(84)85052-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Chandraratna RA, Okamura WH. 12-- conformationally locked retinoids: Thermal and photochemical interconversions leading to new geometric isomers. Tetrahedron Lett 1984. [DOI: 10.1016/s0040-4039(01)80085-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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22
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23
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Spectroscopic properties of molecules related to hindered isomers of retinal. J CHEM SCI 1979. [DOI: 10.1007/bf02880930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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24
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Preparation of sterically hindered geometric isomers of 7-cis-β-ionyl and β-ionylidene derivatives in the vitamin A series. Tetrahedron 1975. [DOI: 10.1016/0040-4020(75)85065-4] [Citation(s) in RCA: 46] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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25
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26
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KOFLER M, RUBIN SH. Physicochemical Assay of Vitamin A and Related Compounds. VITAMINS & HORMONES 1961; 18:315-39. [PMID: 13757520 DOI: 10.1016/s0083-6729(08)60867-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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27
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28
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Wodsak W. Über die Umwandlung des all-trans-Vitamins A in seine Isomeren und die mögliche Bedeutung dieser Isomerisierung für den Abbau des Vitamins A. ACTA ACUST UNITED AC 1958. [DOI: 10.1002/lipi.19580600607] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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BARNHOLDT B, HJARDE W. Chromatographic separation of five vitamin A1 isomers from the eyes of deep-water prawns (Pandalus borealis). ACTA PHYSIOLOGICA SCANDINAVICA 1957; 41:49-67. [PMID: 13497758 DOI: 10.1111/j.1748-1716.1957.tb01509.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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FISHER LR, KON SK, PLACK PA. Vitamin A isomers in some eucaridan Crustacea. PROCEEDINGS OF THE ROYAL SOCIETY OF LONDON. SERIES B, BIOLOGICAL SCIENCES 1957; 147:200-17. [PMID: 13465718 DOI: 10.1098/rspb.1957.0044] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Earlier work in this laboratory showed that the biological activity of vitamin A extracts from some marine Crustacea was lower than that indicated by the Carr–Price test. It was suggested that this discrepancy might have been due to the presence of
cis-isomers
of vitamin A, which give the same quantitative colour reaction in the Carr–Price test but are biologically less active than all-
trans
vitamin A. In this paper, the isomer composition of the vitamin A of two euphausiid Crustacea,
Meganyctiphanes norvegica
(M. Sars) and
Thysanoessa raschii
(M. Sars), and of three decapod Crustacea,
Pandalus bonnieri Caullery
, P.
borealis
Kroyer and P.
montagui
Leach, is reported. The percentages of ‘fast’ (all-
trans
and 9-
cis
vitamin A) and ‘slow’ (13-
cis
, 9:13-di-
cis
, neo-
b
and neo-
c
vitamin A) reacting isomers were calculated from the rate of combination of vitamin A preparations from these species with maleic anhydride in benzene solution. Hindered
cis
-isomers were detected by their rapid isomerization with iodine, which results in an increase of the wavelength of the ultra-violet absorption maximum and a large increase in extinction, and by a high value for the ratio (maximum extinction in the Carr-Price test)/ (maximum extinction in the ultra-violet). The retinenes of these vitamin A isomers were allowed to react with opsin in the dark and the neo-
b
retinene present was measured by the formation of rhodopsin. In all five species studied, the hindered
cis
-isomer, neo-
b
vitamin A, was the most abundant form and constituted 53 to 90 % of the total vitamin A. Another hindered
cis
-isomer, neo-
c
vitamin A, not so far reported from natural sources, was isolated from extracts of
M
.
norvegica
and
T
.
raschii
by fractional chromatography. It constituted about 5% of their total vitamin A. The remainder of the vitamin A was mostly in the all-
trans
form. The calculated biological activities of these mixtures of isomers agreed well with the results of biological assays with rats. As the vitamin A is located in the eyes of these Crustacea, it is possible that it has a visual function. The significance of these findings in relation to the vitamin A food chain in the sea is discussed, and it seems probable that the predators of the Crustacea are able to convert neo-
b
vitamin A into the all -
trans
form.
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Abstract
The vitamin A of the euphausiid crustacean, Meganyctiphanes norvegica, consists almost wholly of the hindered cis isomer, neo-b (11-cis). In this animal vitamin A is concentrated almost entirely in the eyes; and its properties so closely resemble those of pure neo-b vitamin A as not in themselves to indicate that any other isomer is present. However, Fisher et al. (1955 b) have isolated a small fraction from this material which may be neo-c vitamin A (11, 13-dicis). The neo-b isomer was identified by its absolute absorption spectrum, the changes of absorption spectrum on isomerization, oxidation to neo-b retinene, and synthesis from the latter of rhodopsin. This identification is also in good accord with new, revised bioassays of Meganyctiphanes vitamin A by Plack et al. (1956).
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Abstract
In many crustacea, including the lobster, the bulk of the vitamin A of the whole animal is concentrated in the eyes. Recently Fisher, Kon, and Thompson found that vitamin A extracted from the eyes of euphausiid crustacea has only about one half the biological potency of the same amount of the all-trans acetate or fish liver vitamin A. In the present experiments the vitamin A of the lobster eye is found to consist almost entirely of the hindered cis isomer, neo-b, the precursor in the vertebrate retina of the visual pigments rhodopsin and iodopsin. This isomer is known to have a low biological potency in the rat, only about one quarter that of all-trans vitamin A. In the lobster eye it is virtually all extractable with petroleum ether, about 30 per cent in the form of free alcohol, about 70 per cent in the form of esters. It was identified by its absorption spectrum, as derived from measurements on crude extracts, and measured directly in purified preparations; the changes in absorption which accompany isomerization; oxidation to the corresponding retinene; and synthesis from the latter of rhodopsin. The examination of an extract of euphausiid eyes, provided by Dr. Kon, also revealed the presence of neo-b vitamin A virtually alone. This may be the characteristic condition in the eyes of Eucarid crustacea. It is peculiar in that the neo-b isomer, being a sterically hindered form, is ordinarily expected to be represented in any equilibrium mixture of geometric isomers in very small amount. Apparently certain crustacea have ways of circumventing the difficulties implicit in producing and retaining this isomer, and store it in the eye virtually alone.
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MORTON RA, PITT GA. Visual pigments. FORTSCHRITTE DER CHEMIE ORGANISCHER NATURSTOFFE = PROGRESS IN THE CHEMISTRY OF ORGANIC NATURAL PRODUCTS. PROGRES DANS LA CHIMIE DES SUBSTANCES ORGANIQUES NATURELLES 1957; 14:244-316. [PMID: 13597972 DOI: 10.1007/978-3-7091-7164-6_6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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EMBREE ND, AMES SR, LEHMAN RW, HARRIS PL. Determination of vitamin A. METHODS OF BIOCHEMICAL ANALYSIS 1957; 4:43-98. [PMID: 13430363 DOI: 10.1002/9780470110201.ch2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/07/2023]
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Abstract
Rhodopsin is formed by the condensation of opsin with a cis isomer of retinene, called neo-b. The bleaching of rhodopsin releases all-trans retinene which must be isomerized back to neo-b in order for rhodopsin to regenerate. Both retinene isomers are in equilibrium with the corresponding isomers of vitamin A, through the alcohol dehydrogenase system. An enzyme is found in cattle retinas and frog pigment layers which catalyzes the interconversion of all-trans and neo-b retinene. We call it "retinene isomerase." It is soluble in neutral phosphate buffer, and precipitates between 20 and 35 per cent saturation with ammonium sulfate. In the dark, the isomerase converts all-trans and neo-b retinene to an equilibrium mixture of 5 parts neo-b and 95 parts all-trans. With opsin present to trap neo-b, the isomerase catalyzes the synthesis of rhodopsin from all-trans retinene. This reaction, however, is too slow to account for dark adaptation. Retinene is isomerized by light, but too slowly to supply the retina with neo-b. In aqueous solution the pseudoequilibrium mixture contains about 15 per cent neo-b. When all-trans retinene is irradiated in the presence of isomerase, the rate of formation of neo-b is increased about 5 times, and the pseudoequilibrium shifted so that the mixture now contains about 32 per cent neo-b. The isomerase is specific for all-trans and neo-b retinene. It does not act on two other cis isomers of retinene, nor on all-trans or neo-b vitamin A. The role of the isomerase in vision appears to be as follows: in the light, as rhodopsin is bleached to opsin and all-trans retinene, the latter is in part converted to the neo-b isomer and stored in the pigment epithelium as neo-b vitamin A. During dark adaptation, the dominant process is the trapping by opsin of neo-b retinene supplied from stores of neo-b vitamin A, and the slow isomerase-catalyzed "dark" conversion of all-trans to neo-b retinene.
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