caa a22 4500 469083131 CHVBK 20180323132956.0 cr unu---uuuuu 170328e19921001xx s 000 0 eng 10.1007/BF00381879 doi (NATIONALLICENCE)springer-10.1007/BF00381879 Rhabdomeric membrane and smooth endoplasmic reticulum in photoreceptors of Manduca sexta [Elektronische Daten] modulations associated with the diurnal light/dark cycle and effects of chromophore deprivation [Richard White, Ruth Bennett] Summary: Aberrations of photoreceptor ultrastructure resulting from carotenoid/retinoid (vitamin A) deprivation were studied in the retina of Manduca sexta. The syndrome of chromophore deficiency included hypertrophy of smooth endoplasmic reticulum, variable dilation of rhabdomeric microvilli, the insertion of endomembrane fingers into such enlarged microvilli, and the formation of ‘rhabdomeric vacuoles', intracellular compartments containing microvilli similar to those of the rhabdomere. Retinas were processed either with conventional procedures employing preliminary aldehyde fixation followed by heavy metal postfixation, or by fixation and incubation in unbuffered OsO4. The latter method deposits osmium throughout the endomembrane system, within the rhabdomeric vacuoles, and in the extracellular space of the rhabdom. However, the intravillous fingers were rarely impregnated with osmium, despite their continuity with densely stained cisternae of the smooth endoplasmic reticulum. We suggest that the insertion of endomembrane fingers into dilated microvilli results from a cytoskeleton-mediated link between cisternae of the smooth endoplasmic reticulum and the rhabdomeric membrane, an association that may be important in the turnover of photoreceptor membrane. We interpret endomembrane hypertrophy and development of rhabdomeric vacuoles as symptoms of disturbance in the pathway leading to the assembly of the rhabdomere resulting from reduced synthesis of visual pigment. Springer-Verlag, 1992 Photoreceptors cells nationallicence Retinoid deficiency nationallicence Rhabdom nationallicence Endomembrane nationallicence Tobacco hornworm moth, Manduca sexta (Insecta) nationallicence White Richard Department of Biology, University of Massachusetts at Boston, Harbor Campus, 02125, Boston, MA, USA aut Bennett Ruth Department of Biology, University of Massachusetts at Boston, Harbor Campus, 02125, Boston, MA, USA aut Cell and Tissue Research Springer-Verlag 270/1(1992-10-01), 57-64 0302-766X 270:1<57 1992 270 441 https://doi.org/10.1007/BF00381879 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00381879 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- White Richard Department of Biology, University of Massachusetts at Boston, Harbor Campus, 02125, Boston, MA, USA aut NATIONALLICENCE 700 1- Bennett Ruth Department of Biology, University of Massachusetts at Boston, Harbor Campus, 02125, Boston, MA, USA aut NATIONALLICENCE 773 0- Cell and Tissue Research Springer-Verlag 270/1(1992-10-01), 57-64 0302-766X 270:1<57 1992 270 441 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer