Cone photopigments in nocturnal and diurnal procyonids

1992 ◽  
Vol 171 (3) ◽  
pp. 351-358 ◽  
Author(s):  
Gerald H. Jacobs ◽  
Jess F. Deegan
Keyword(s):  
Cone Photopigments

Abnormalities of Cone Photopigments in Genetic Carriers of Protanomaly

1984 ◽  
Vol 102 (6) ◽  
pp. 897-900 ◽  
Author(s):  
T. Yasuma ◽  
H. Tokuda ◽  
H. Ichikawa
Keyword(s):  
Cone Photopigments

scholarly journals Immunocytochemical localization of opsin in outer segments and Golgi zones of frog photoreceptor cells. An electron microscope analysis of cross-linked albumin-embedded retinas

1978 ◽  
Vol 77 (1) ◽  
pp. 196-210 ◽  
Author(s):  
DS Papermaster ◽  
BG Schneider ◽  
MA Zorn ◽  
JP Kraehenbuhl
Keyword(s):  
Electron Microscope ◽  
Outer Segment ◽  
Specific Binding ◽  
Photoreceptor Cells ◽  
Indirect Detection ◽  
Thin Sections ◽  
Rods And Cones ◽  
Outer Segments ◽  
Cell Structures ◽  
Cone Photopigments

Adult vertebrate retinal cells (rod and cones) continuously synthesize membrane proteins and transport them to the organelle specialized for photon capture, the outer segment. The cell structures involved in the synthesis of opsin have been identified by means of immunocytochemistry at the electron microscope level. Two indirect detection systems were used: (a) rabbit antibodies to frog opsin were localized with ferritin conjugated F(ab')2 of sheep antibodies to rabbit F(ab')2 and (b) sheep antibodies to cattle opsin were coupled to biotin and visualized by means of avidin-ferritin conjugates (AvF). The reagents were applied directly to the surface of thin sections of frog retinal tissues embedded in glutaraldehyde cross-linked bovine serum albumin (BSA). Specific binding of anti-opsin antibodies indicates that opsin is localized in the disks of rod outer segments (ROS), as expected, and in the Golgi zone of the rod cell inner segments. In addition, we observed quantitatively different labeling patterns of outer segments of rods and cones with each of the sera employed. These reactions may indicate immunological homology of rod and cone photopigments. Because these quantitiative variations of labeling density extend along the entire length of the outer segment, they also serve to identify the cell which has shed its disks into adjacent pigment ipithelial cell phagosomes.

scholarly journals Non-photopic and photopic visual cycles differentially regulate immediate, early and late-phases of cone photoreceptor-mediated vision

2020 ◽  
Author(s):  
Rebecca Ward ◽  
Joanna J. Kaylor ◽  
Diego F. Cobice ◽  
Dionissia A. Pepe ◽  
Eoghan M. McGarrigle ◽  
...  
Keyword(s):  
Pigment Epithelium ◽  
Retinal Pigment ◽  
Bright Light ◽  
Immediate Early ◽  
Light Conditions ◽  
Photopic Vision ◽  
Wide Range ◽  
Dihydroceramide Desaturase ◽  
Cone Photopigments ◽  
Dihydroceramide Desaturase 1

AbstractCone photoreceptors in the retina enable vision over a wide range of light intensities. However, the processes enabling cone vision in bright light (i.e. photopic vision) are not adequately understood. Chromophore regeneration of cone photopigments may require the retinal pigment epithelium (RPE) and/or retinal Müller glia. In the RPE, isomerization of all-trans-retinyl esters (atRE) to 11-cis-retinol (11cROL) is mediated by the retinoid isomerohydrolase Rpe65. An alternative retinoid isomerase, dihydroceramide desaturase-1 (DES1), is expressed in RPE and Müller cells. The retinol-isomerase activities of Rpe65 and Des1 are inhibited by emixustat and fenretinide, respectively. Here, we tested the effects of these visual cycle inhibitors on immediate, early and late phases of cone photopic vision. In zebrafish larvae raised under cyclic light conditions, fenretinide impaired late cone photopic vision, whereas emixustat-treated zebrafish unexpectedly had normal vision. In contrast, emixustat-treated larvae raised under extensive dark-adaption displayed significantly attenuated immediate photopic vision concomitantly with significantly reduced 11-cis-retinaldehyde (11cRAL). Following 30 minutes of light, early photopic vision recovered, despite 11cRAL levels remaining significantly reduced. Defects in immediate cone photopic vision were rescued in emixustat- or fenretinide-treated larvae following exogenous 9-cis-retinaldehyde (9cRAL) supplementation. Genetic knockout of degs1 or retinaldehyde-binding protein 1b (rlbp1b) revealed that neither are required for photopic vision in zebrafish. Our findings define the molecular and temporal requirements of the non-photopic and photopic visual cycles for mediating vision in bright light.

Aging and human cone photopigments

1988 ◽  
Vol 5 (12) ◽  
pp. 2106 ◽  
Author(s):  
Ann E. Elsner ◽  
Lawrence Berk ◽  
Stephen A. Burns ◽  
Paul R. Rosenberg
Keyword(s):  
Cone Photopigments

Kinetics of human cone photopigments explained with a Rushton-Henry model

1988 ◽  
Vol 58 (2) ◽  
pp. 123-128 ◽  
Author(s):  
A. C. C. Coolen ◽  
D. van Norren
Keyword(s):  
Cone Photopigments ◽  
Kinetics Of

scholarly journals Peripheral photopic sensitivity to melanopsin and cone photopigments

2012 ◽  
Vol 12 (9) ◽  
pp. 52-52
Author(s):  
H. Horiguchi ◽  
J. Winawer ◽  
R. F. Dougherty ◽  
B. A. Wandell
Keyword(s):  
Cone Photopigments

scholarly journals Non-photopic and photopic visual cycles differentially regulate immediate, early, and late phases of cone photoreceptor-mediated vision

2020 ◽  
Vol 295 (19) ◽  
pp. 6482-6497 ◽  
Author(s):  
Rebecca Ward ◽  
Joanna J. Kaylor ◽  
Diego F. Cobice ◽  
Dionissia A. Pepe ◽  
Eoghan M. McGarrigle ◽  
...  
Keyword(s):  
Pigment Epithelium ◽  
Retinal Pigment ◽  
Bright Light ◽  
Immediate Early ◽  
Light Conditions ◽  
Photopic Vision ◽  
Wide Range ◽  
Dihydroceramide Desaturase ◽  
Cone Photopigments ◽  
Dihydroceramide Desaturase 1

Cone photoreceptors in the retina enable vision over a wide range of light intensities. However, the processes enabling cone vision in bright light (i.e. photopic vision) are not adequately understood. Chromophore regeneration of cone photopigments may require the retinal pigment epithelium (RPE) and/or retinal Müller glia. In the RPE, isomerization of all-trans-retinyl esters to 11-cis-retinol is mediated by the retinoid isomerohydrolase Rpe65. A putative alternative retinoid isomerase, dihydroceramide desaturase-1 (DES1), is expressed in RPE and Müller cells. The retinol-isomerase activities of Rpe65 and Des1 are inhibited by emixustat and fenretinide, respectively. Here, we tested the effects of these visual cycle inhibitors on immediate, early, and late phases of cone photopic vision. In zebrafish larvae raised under cyclic light conditions, fenretinide impaired late cone photopic vision, while the emixustat-treated zebrafish unexpectedly had normal vision. In contrast, emixustat-treated larvae raised under extensive dark-adaptation displayed significantly attenuated immediate photopic vision concomitant with significantly reduced 11-cis-retinaldehyde (11cRAL). Following 30 min of light, early photopic vision was recovered, despite 11cRAL levels remaining significantly reduced. Defects in immediate cone photopic vision were rescued in emixustat- or fenretinide-treated larvae following exogenous 9-cis-retinaldehyde supplementation. Genetic knockout of Des1 (degs1) or retinaldehyde-binding protein 1b (rlbp1b) did not eliminate photopic vision in zebrafish. Our findings define molecular and temporal requirements of the nonphotopic or photopic visual cycles for mediating vision in bright light.

Losses of functional opsin genes, short-wavelength cone photopigments, and color vision—A significant trend in the evolution of mammalian vision

2013 ◽  
Vol 30 (1-2) ◽  
pp. 39-53 ◽  
Author(s):  
GERALD H. JACOBS
Keyword(s):  
Color Vision ◽  
Short Wavelength ◽  
Mammalian Species ◽  
Gene Families ◽  
Opsin Gene ◽  
Cone Type ◽  
Opsin Genes ◽  
Single Cone ◽  
Cone Pigments ◽  
Cone Photopigments

AbstractAll mammalian cone photopigments are derived from the operation of representatives from two opsin gene families (SWS1 and LWS in marsupial and eutherian mammals; SWS2 and LWS in monotremes), a process that produces cone pigments with respective peak sensitivities in the short and middle-to-long wavelengths. With the exception of a number of primate taxa, the modal pattern for mammals is to have two types of cone photopigment, one drawn from each of the gene families. In recent years, it has been discovered that the SWS1 opsin genes of a widely divergent collection of eutherian mammals have accumulated mutational changes that render them nonfunctional. This alteration reduces the retinal complements of these species to a single cone type, thus rendering ordinary color vision impossible. At present, several dozen species from five mammalian orders have been identified as falling into this category, but the total number of mammalian species that have lost short-wavelength cones in this way is certain to be much larger, perhaps reaching as high as 10% of all species. A number of circumstances that might be used to explain this widespread cone loss can be identified. Among these, the single consistent fact is that the species so affected are nocturnal or, if they are not technically nocturnal, they at least feature retinal organizations that are typically associated with that lifestyle. At the same time, however, there are many nocturnal mammals that retain functional short-wavelength cones. Nocturnality thus appears to set the stage for loss of functional SWS1 opsin genes in mammals, but it cannot be the sole circumstance.

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