scholarly journals Photoreceptors in the crayfish compound eye: electrical interactions between cells as related to polarized-light sensitivity

1973 ◽  
Vol 232 (3) ◽  
pp. 573-595 ◽  
Author(s):  
Kenneth J. Muller
Keyword(s):  
Compound Eye ◽  
Polarized Light ◽  
Light Sensitivity

The tiered retina of Dytiscus : a new type of compound eye

1970 ◽  
Vol 175 (1038) ◽  
pp. 83-94 ◽  
Keyword(s):  
Compound Eye ◽  
Electrical Coupling ◽  
Polarized Light ◽  
Light Sensitivity ◽  
Sectional Area ◽  
Cross Sectional ◽  
Light Passing ◽  
Small Fields ◽  
New Type ◽  
Different Levels

The retina of Dytiscus is tiered, with proximal and distal layers of receptors at different levels. Photoreceptor units of the proximal retina of the eye of Dytiscus have fields of view so wide that light entering by any facet is able to excite a receptor belonging virtually to any ommatidium in the light- or dark-adapted eye. Although the distal rhabdomeres may have small fields of view, the proximal retina is clearly not adapted for perception of form or movement. The sensitivity of proximal retinula units is compatible with the observations that light passing through many facets sums upon them and that their rhabdomeres are relatively large and jointly occupy the whole cross-sectional area of the eye. The lack of polarized light sensitivity of the proximal retinula units can be attributed to electrical coupling between cells with tubules oriented in different directions within each ommatidium.

Light Sensitivity of the Compound Eye of a Moth (Manduca Sexta) Reared on a Retinol Deficient Diet

1972 ◽  
Vol 84 (3) ◽  
pp. 289-294 ◽  
Author(s):  
Jörgen Boëthius ◽  
StanleyD. Carlson ◽  
Gunnar Hoglund ◽  
Goran Struwe
Keyword(s):  
Manduca Sexta ◽  
Compound Eye ◽  
Light Sensitivity ◽  
Deficient Diet

scholarly journals Homothorax controls a binary Rhodopsin switch in Drosophila ocelli

PLoS Genetics ◽  
2021 ◽  
Vol 17 (7) ◽  
pp. e1009460
Author(s):  
Abhishek Kumar Mishra ◽  
Cornelia Fritsch ◽  
Roumen Voutev ◽  
Richard S. Mann ◽  
Simon G. Sprecher
Keyword(s):  
Drosophila Melanogaster ◽  
Visual Perception ◽  
Compound Eye ◽  
Polarized Light ◽  
Fruit Fly ◽  
Compound Eyes ◽  
Ancestral Gene ◽  
Evolutionary Diversification ◽  
Opsin Genes ◽  
A Cell

Visual perception of the environment is mediated by specialized photoreceptor (PR) neurons of the eye. Each PR expresses photosensitive opsins, which are activated by a particular wavelength of light. In most insects, the visual system comprises a pair of compound eyes that are mainly associated with motion, color or polarized light detection, and a triplet of ocelli that are thought to be critical during flight to detect horizon and movements. It is widely believed that the evolutionary diversification of compound eye and ocelli in insects occurred from an ancestral visual organ around 500 million years ago. Concurrently, opsin genes were also duplicated to provide distinct spectral sensitivities to different PRs of compound eye and ocelli. In the fruit fly Drosophila melanogaster, Rhodopsin1 (Rh1) and Rh2 are closely related opsins that originated from the duplication of a single ancestral gene. However, in the visual organs, Rh2 is uniquely expressed in ocelli whereas Rh1 is uniquely expressed in outer PRs of the compound eye. It is currently unknown how this differential expression of Rh1 and Rh2 in the two visual organs is controlled to provide unique spectral sensitivities to ocelli and compound eyes. Here, we show that Homothorax (Hth) is expressed in ocelli and confers proper rhodopsin expression. We find that Hth controls a binary Rhodopsin switch in ocelli to promote Rh2 expression and repress Rh1 expression. Genetic and molecular analysis of rh1 and rh2 supports that Hth acts through their promoters to regulate Rhodopsin expression in the ocelli. Finally, we also show that when ectopically expressed in the retina, hth is sufficient to induce Rh2 expression only at the outer PRs in a cell autonomous manner. We therefore propose that the diversification of rhodpsins in the ocelli and retinal outer PRs occurred by duplication of an ancestral gene, which is under the control of Homothorax.

scholarly journals Polarized light sensitivity in Pieris rapae is dependent on both color and intensity

2020 ◽  
Vol 223 (13) ◽  
pp. jeb220350 ◽  
Author(s):  
Adam J. Blake ◽  
Gina S. Hahn ◽  
Hayley Grey ◽  
Shelby A. Kwok ◽  
Deby McIntosh ◽  
...  
Keyword(s):  
Pieris Rapae ◽  
Polarized Light ◽  
Light Sensitivity
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