Structure of photoreceptive membranes of Drosophila compound eyes as studied by quick-freezing electron microscopy.
Photoreceptive membranes of Drosophila compound eyes were studied by quick-freezing electron microscopy. The quick-frozen photoreceptive microvilli appeared cylindrical in shape either when they were freeze-substituted or freeze-fractured. Deep-etch replication revealed the extracellular surfaces of microvilli which were covered by various particles arranged in a helical manner. The protoplasmic surfaces were covered by more regular helical rows of particles about 10 nm in diameter. When rhodopsin content of the photoreceptive membranes was reduced by vitamin A-deficiency, the intramembrane particles drastically decreased resulting in the disappearance of particles in rows. Our results strongly suggest the regular arrangement of rhodopsin molecules in invertebrate photoreceptive membranes.
Department of Fine Morphology, University of Tokyo, Japan.
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E
Suzuki
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E
Katayama
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Hirosawa
D000818:Animals; D004331:Drosophila melanogaster / Q000648:ultrastructure*; D005613:Freeze Etching; D005614:Freeze Fracturing; D008854:Microscopy, Electron / Q000379:methods*; D008871:Microvilli / Q000648:ultrastructure; D010786:Photoreceptor Cells / Q000648:ultrastructure*; D012243:Rhodopsin / Q000648:ultrastructure; D014802:Vitamin A Deficiency / Q000473:pathology
D012243:Rhodopsin