Localization of retinal photoisomerase in the compound eye of the honeybee

1991 ◽  
Vol 7 (3) ◽  
pp. 237-249 ◽  
Author(s):  
W. Clay Smith ◽  
Timothy H. Goldsmith
Keyword(s):  
Immunoelectron Microscopy ◽  
Compound Eye ◽  
Polyclonal Antibodies ◽  
Photoreceptor Cells ◽  
Proximal Portion ◽  
Pigment Cells ◽  
High Concentration ◽  
Peripheral Portion

AbstractThe distribution of honeybee retinal photoisomerase, a soluble light-requiring enzyme that stereospecifically forms W-cis retinal, was investigated by immunoelectron microscopy and by HPLC. Immunolocalization with polyclonal antibodies shows that the highest concentration of retinal photoisomerase is located in the proximal portion of the primary pigment cells in large aggregates (approximately 2 μm diameter).Photoisomerase is also located in the peripheral portion of the photoreceptor cells, laterally displaced from the rhabdom, but in much lower concentration. Because of the larger volume of the photoreceptor cells, about half of the total immunoreactivity is associated with the primary pigment cells.Dissection of the eye with the subsequent use of HPLC to assay for photoisomerase activity showed that most of the photoisomerase activity is associated with tissues near the cornea. The same tissue also supports the reduction of W-cis retinal to W-cis retinol. These biochemical findings are consistent with the immunolocalization of retinal photoisomerase to the high-concentration aggregates in the primary pigment cells that surround the crystalline cones. The major synthesis of W-cis retinol therefore takes place in the primary pigment cells, and the retinoid must be moved into the photoreceptor cells to be available to newly synthesized opsin. The immunoreactivity of the photoreceptor cells appears to reflect the presence of some isomerase without an attached retinoid chromophore.

Actin and α-tubulin immuno-EM labelings reveal differences in intra versus interphotoreceptor matrix

1990 ◽  
Vol 48 (3) ◽  
pp. 466-467
Author(s):  
Matti Järvilehto ◽  
Riitta Harjula
Keyword(s):  
Compound Eye ◽  
Frozen Section ◽  
Smooth Muscle Actin ◽  
Photoreceptor Cells ◽  
Immune Serum ◽  
Cell Organelles ◽  
Calliphora Erythrocephala ◽  
Optical Axes ◽  
Interphotoreceptor Matrix ◽  
Similar Kind

The photoreceptor cells in the compound eyes of higher diptera are clustered in groups (ommatidia) of eight receptor cells. The cells from six adjacent ommatidia are organized into optical units, neuro-ommatia sharing the same visual field. In those ommatidia the optical axes of the photopigment containing structures (rhabdomeres) are parallel. The rhabdomeres of the photoreceptor cells are separated from each other by an interstitial i.e innerommatidial space (IOS). In the photoreceptor cell body, besides of the normal cell organelles, a cellular matrix is a structurally apparent component. Similar kind of reticular formation is also found in the IOS containing some unidentified filamentary substance, of which composition and functional significance for optical properties of vision is the aim of this report.The prefixed (2% PA + 0.2% GA in 0.1-n phosphate buffer, pH 7.4, for 1h), frozen section blocks of the compound eye of the blowfly (Calliphora erythrocephala) were prepared by immuno-cryo-techniques. The ultrathin cryosections were incubated with antibodies of monoclonal α-tubulin and polyclonal smooth muscle actin. Control labelings of excess of antigen, non-immune serum and non-present antibody were perforated.

scholarly journals INHERITED RETINAL DYSTROPHY IN THE RAT

1962 ◽  
Vol 14 (1) ◽  
pp. 73-109 ◽  
Author(s):  
John E. Dowling ◽  
Richard L. Sidman
Keyword(s):  
Pigment Epithelium ◽  
Light And Electron Microscopy ◽  
Retinal Dystrophy ◽  
Photoreceptor Cells ◽  
Pigment Cells ◽  
Membrane Thickness ◽  
Outer Segments ◽  
Progressive Loss ◽  
Retinal Rods ◽  
Microscopy Data

Retinal dystrophies, known in man, dog, mouse, and rat, involve progressive loss of photoreceptor cells with onset during or soon after the developmental period. Functional (electroretinogram), chemical (rhodopsin analyses) and morphological (light and electron microscopy) data obtained in the rat indicated two main processes: (a) overproduction of rhodopsin and an associated abnormal lamellar tissue component, (b) progressive loss of photoreceptor cells. The first abnormality recognized was the appearance of swirling sheets or bundles of extracellular lamellae between normally developing retinal rods and pigment epithelium; membrane thickness and spacing resembled that in normal outer segments. Rhodopsin content reached twice normal values, was present in both rods and extracellular lamellae, and was qualitatively normal, judged by absorption maximum and products of bleaching. Photoreceptors attained virtually adult form and ERG function. Then rod inner segments and nuclei began degenerating; the ERG lost sensitivity and showed selective depression of the a-wave at high luminances. Outer segments and lamellae gradually degenerated and rhodopsin content decreased. No phagocytosis was seen, though pigment cells partially dedifferentiated and many migrated through the outer segment-debris zone toward the retina. Eventually photoreceptor cells and the b-wave of the ERG entirely disappeared. Rats kept in darkness retained electrical activity, rhodopsin content, rod structure, and extracellular lamellae longer than litter mates in light.

Distribution of the myosin I-like ninaC proteins in the Drosophila retina and ultrastructural analysis of mutant phenotypes

1992 ◽  
Vol 101 (1) ◽  
pp. 247-254 ◽  
Author(s):  
J.L. Hicks ◽  
D.S. Williams
Keyword(s):  
Compound Eye ◽  
Photoreceptor Cells ◽  
Amino Acid Sequences ◽  
Ultrastructural Analysis ◽  
Multivesicular Bodies ◽  
Filamentous Actin ◽  
Electron Microscopic ◽  
Myosin I ◽  
Specific Proteins ◽  
Mutant Phenotypes

The Drosophila ninaC gene encodes for two head-specific proteins of 132 kDa and 174 kDa. Their predicted amino acid sequences indicate that they may have myosin I and kinase properties. We have: (1) determined the cellular and subcellular distributions of the ninaC proteins in the Drosophila retina by electron microscopic immunocytochemistry with an antibody specific for epitopes shared by both proteins; (2) characterized the ultrastructure of the mutant phenotype. The proteins were detected only in the photoreceptor cells, but were detected in all classes of the compound eye photoreceptors. Within the photoreceptors, they were found in the rhabdomeral microvilli and the cytoplasm adjacent to the rhabdomeres. This distribution coincides with that shown previously for actin filaments. Immunolabelling of tissue from the ninaC P221 mutant, which lacks the 174 kDa protein, and two mutants whose rhabdomeres degenerate, suggests that the 132 kDa protein is present primarily in the cytoplasm adjacent to the rhabdomeres, and that the 174 kDa protein is concentrated in the rhabdomeres. Our ultrastructural analysis showed that the axial cytoskeleton of the rhabdomeral microvilli (which contains filamentous actin) was absent in both the null and P221 mutants. In the photoreceptor cell cytoplasm, the number of multivesicular bodies in the null mutant, but not the P221 mutant, was 3-fold greater in comparison with wild-type.(ABSTRACT TRUNCATED AT 250 WORDS)

The role of sodium chloride in the process of induction by lithium chloride in cells of the Rana pipiens gastrula

Development ◽  
1968 ◽  
Vol 19 (3) ◽  
pp. 387-396
Author(s):  
Lester G. Barth ◽  
Lucena J. Barth
Keyword(s):  
Sodium Chloride ◽  
Culture Medium ◽  
Rana Pipiens ◽  
Divalent Cations ◽  
Pigment Cells ◽  
Distilled Water ◽  
Sodium Ions ◽  
Monovalent Cations ◽  
High Concentration

A study of the effects of a series of monovalent cations, Li+, Na+ and K+, and a series of divalent cations, Mn2+, Ca2+ and Mg2+, upon small aggregates of cells taken from the presumptive epidermis of Rana pipiens gastrulae revealed that these ions induce nerve and pigment cells (Barth, 1965). The effectiveness of both series of ions as inductors was similar to their effects on decreasing the electrophoretic mobility of DNA as determined by Ross & Scruggs (1964). When it was found that sucrose in glass-distilled water also would induce nerve and pigment cells the role of ions as inductors came under closer scrutiny. A study of the nature of the induction by sucrose revealed that a relatively high concentration of sodium ions was necessary in the culture medium used after sucrose treatment (Barth, 1966).

A Peculiar Kind of Pigment Cell in the Compound Eye of Lepisma saccharina L. (Thysanura)

1973 ◽  
Vol 4 (2) ◽  
pp. 87-90 ◽  
Author(s):  
Rolf Elofsson
Keyword(s):  
Basal Lamina ◽  
Light Microscope ◽  
Compound Eye ◽  
Pigment Cell ◽  
Pigment Cells ◽  
Pigment Granules ◽  
A Cell ◽  
Lepisma Saccharina

AbstractThe ultrastructure of the primary pigment cells of the compound eye of Lepisma saccharina is described. The cells are four in number. The pigment granules are contained in fingerlike protrusions from the pigment cells. These protrusions project into the enlarged basal lamina surrounding the ommatidial top. The large basal lamina could have given the impression of a cell (called corneagen) in the light microscope.

The accuracy of the patterns of connexions of the first- and second-order neurons of the visual system of Calliphora

1970 ◽  
Vol 175 (1038) ◽  
pp. 69-82 ◽  
Keyword(s):  
Single Neuron ◽  
Compound Eye ◽  
Photoreceptor Cells ◽  
Mirror Image ◽  
Second Order ◽  
Visual Axis ◽  
First Order ◽  
Definite Pattern ◽  
Small Bundle ◽  
Do So

The axons of the primary photoreceptor cells of the compound eye of the fly interweave in a complex but definite pattern before they terminate upon the second-order neurons. Of approximately 650 short retinula axons from behind 120 facets of the eye none terminated at an incorrect lamina cartridge. Six, seven, or eight first-order terminals upon one pair of second-order cells are arranged in a rotational sequence that is related to the positions of the retinula cells within the ommatidia. Errors in location of the terminal among its neighbours occurred only ten times. The asymmetry of the receptor pattern in the dorsal half of the eye has a mirror image in the ventral half. Along the equator of the eye is a plane of symmetry which many axons necessarily cross in maintaining the appropriate connexions of their receptors. Axons which cross this plane of symmetry have somehow found their appropriate second-order cells, although to do so they must have grown through a milieu which is the mirror image of that in their own half of the eye. Each pair of second-order axons proceeding from the lamina forms a small bundle with the axons of the two long retinula cells that have the same visual axis. Between the lamina and the medulla is a chiasma (with the crossing in the horizontal plane) through which bundles from the lamina pass to project in exactly reverse order upon the medulla. No errors of projection have been found at the single neuron level in this chiasma.

scholarly journals Orange Capsicums and Chillies as a Potential Source of Dietary Zeaxanthin, an Important Macular Carotenoid for Eye Health

Proceedings ◽  
2020 ◽  
Vol 36 (1) ◽  
pp. 161
Author(s):  
Rimjhim Agarwal ◽  
Hung Hong Trieu ◽  
Robyn Cave ◽  
Stephen Harper ◽  
Tim O’Hare
Keyword(s):  
High Performance ◽  
Beta Carotene ◽  
Photoreceptor Cells ◽  
Developed Countries ◽  
High Concentration ◽  
High Accumulation ◽  
Orange Pigment ◽  
Before And After ◽  
Yellow Orange ◽  
Orange Colour

Zeaxanthin is a dietary carotenoid accumulated in the macula in order to reduce photoreceptor oxidation by blue light. Damage caused to photoreceptor cells in the human eye leads to macular degeneration, which is the leading cause of blindness in developed countries. Zeaxanthin, an orange pigment, is rarer in western diets as compared to the yellow pigment, lutein, the other important macular carotenoid. Orange capsicums (Capsicum annuum) have been reported to be an excellent source of zeaxanthin, but there are limited reports about its occurrence both within, and in other closely related species (C. baccatum, C. chinense). In the current investigation, yellow, orange and red coloured accessions of C. annuum, C. chinense and C. baccatum were analysed for their carotenoid profiles to identify high zeaxanthin accessions. A carotenoid extraction protocol and ultra-high-performance liquid chromatography-photometric diode array-mass spectrometry (UHPLC-PDA-MS) analysis was optimised to identify and quantify carotenoids in the capsicum accessions both before and after saponification. Interestingly, out of 22 varieties tested, only the ‘Orange Belle’ orange capsicum demonstrated a high accumulation of zeaxanthin. Other accessions exhibiting orange colour accumulated different orange carotenoid pigments to zeaxanthin, such as violaxanthin, beta-carotene, and beta-cryptoxanthin. Yellow coloured accessions accumulated a high concentration of lutein or alpha-carotene, while red cultivars were highest in capsanthin and capsorubin. The present findings suggests a need for further studies to identify high zeaxanthin germplasm which can be cross-bred with orange capsicums for future biofortification, in order to help increase the daily dietary intake of zeaxanthin in western diets.

scholarly journals Type VI collagen in extracellular, 100-nm periodic filaments and fibrils: identification by immunoelectron microscopy.

1986 ◽  
Vol 103 (2) ◽  
pp. 393-404 ◽  
Author(s):  
R R Bruns ◽  
W Press ◽  
E Engvall ◽  
R Timpl ◽  
J Gross
Keyword(s):  
Immunoelectron Microscopy ◽  
Polyclonal Antibodies ◽  
Structural Characteristics ◽  
Rabbit Antiserum ◽  
Type Vi Collagen ◽  
Thin Sections ◽  
Prolonged Incubation ◽  
Fibroblast Cultures ◽  
Band Region ◽  
Wide Range

Filaments and fibrils that exhibit a 100-nm axial periodicity and occur in the medium and in the deposited extracellular matrix of chicken embryo and human fibroblast cultures have been tentatively identified with type VI collagen on the basis of their similar structural characteristics (Bruns, R. R., 1984, J. Ultrastruct. Res., 89:136-145). Using indirect immunoelectron microscopy and specific monoclonal and polyclonal antibodies, we now report their positive identification with collagen VI and their distribution in fibroblast cultures and in tendon. Primary human foreskin fibroblast cultures, labeled with anti-type VI antibody and studied by fluorescence microscopy, showed a progressive increase in labeling and changes in distribution with time up to 8 d in culture. With immunoelectron microscopy and monoclonal antibodies to human type VI collagen followed by goat anti-mouse IgG coupled to colloidal gold, they showed in thin sections specific 100-nm periodic labeling on extracellular filaments and fibrils: one monoclonal antibody (3C4) attached to the band region and another (4B10) to the interband region of the filaments and fibrils. Rabbit antiserum to type VI collagen also localized on the band region, but the staining was less well defined. Control experiments with antibodies to fibronectin and to procollagen types I and III labeled other filaments and fibrils, but not those with a 100-nm period. Heavy metal-stained fibrils with the same periodic and structural characteristics also have been found in both adult rat tail tendon and embryonic chicken tendon subjected to prolonged incubation in culture medium or treatment with adenosine 5'-triphosphate at pH 4.6. We conclude that the 100-nm periodic filaments and fibrils represent the native aggregate form of type VI collagen. It is likely that banded fibrils of the same periodicity and appearance, reported by many observers over the years in a wide range of normal and pathological tissues, are at least in part, type VI collagen.

The morphology of the dorsal eye of the hydrothermal vent shrimp, Rimicaris exoculata

1995 ◽  
Vol 12 (5) ◽  
pp. 861-875 ◽  
Author(s):  
Patrick J. O'Neill ◽  
Robert N. Jinks ◽  
Erik D. Herzog ◽  
Barbara-Anne Battelle ◽  
Leonard Kass ◽  
...  
Keyword(s):  
Hydrothermal Vent ◽  
Hydrothermal Vents ◽  
Compound Eye ◽  
Thick Layer ◽  
Dorsal Surface ◽  
Volume Density ◽  
Pigment Cells ◽  
Body Volume ◽  
Rimicaris Exoculata ◽  
Screening Pigment

AbstractThe bresiliid shrimp, Rimicaris exoculata, lives in large masses on the sides of hydrothermal vent chimneys at two sites on the Mid-Atlantic Ridge. Although essentially no daylight penetrates to depths of 3500 m, very dim light is emitted from the hydrothermal vents themselves. To exploit this light, R. exoculata has evolved a modified compound eye on its dorsal surface that occupies about 0.5% of the animal's body volume. The eye's morphology suggests that it is extremely sensitive to light. The cornea of the dorsal eye is smooth with no dioptric apparatus. The retina consists of two wing-shaped lobes that are fused across the midline anteriorly. The rhabdomeral segments of the 7000 ommatidia form a compact layer of photosensitive membrane with an entrance aperture of more than 26 mm2. Within this layer, the volume density of rhabdom is more than 70%. Below the rhabdomeral segments, a thick layer of white diffusing cells scatters light upward into the photoreceptors. The arhabdomeral segments of the five to seven photoreceptors of each ommatidium are mere strands of cytoplasm that expand to accommodate the photoreceptor nuclei. The rhabdom is comprised of well-organized arrays of microvilli, each with a cytoskeletal core. The rhabdomeral segment cytoplasm contains mitochondria, but little else. The perikaryon contains a band of mitochondria, but has only small amounts of endoplasmic reticulum. There is no ultrastructural indication of photosensitive membrane cycling in these photoreceptors. Vestigial screening pigment cells and screening pigment granules within the photoreceptors are both restricted to the inner surface of the layer of the white diffusing cells. Below the retina, photoreceptor axons converge in a fan-shaped array to enter the dorsal surface of the brain. The eye's size and structure are consistent with a role for vision in shrimp living at abyssal hydrothermal vents.

A new species of Dendrocephalus (Crustacea, Anostraca) from Serra dos Carajás (Pará State, Brasil)

Zootaxa ◽  
2012 ◽  
Vol 3363 (1) ◽  
pp. 52 ◽  
Author(s):  
D. CHRISTOPHER ROGERS ◽  
JOÃO PEDRO CORRÊA GOMES ◽  
FABIO VIEIRA
Keyword(s):  
New Species ◽  
Compound Eye ◽  
Proximal Portion ◽  
Fairy Shrimp ◽  
Amazonian Forest ◽  
Temporary Pool ◽  
A New Species

Dendrocephalus carajaensis, a new species of fairy shrimp, is described from a single temporary pool in canga deposits on theSerra Sul plateau, Serra dos Carajás region in Brazilian Amazonian forest, Pará State, Brasil. D. carajaensis sp. nov. males arereadily separated from all other Dendrocephalus species except D. brasiliensis and D. spartaenovae by the absence of a spineon the posterioventral surface of the compound eye. This species is separated from D. brasiliensis and D. spartaenovae by theform of the proximal portion of the frontal appendage and the endopodites of the first three thoracopods. This species appears to be endemic to the Serra dos Carajás.

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