Lipid-Rhodopsin Interactions in Photoreceptor Membranes

Author(s):  
Robert E. Anderson
Author(s):  
A. Tonosaki ◽  
M. Yamasaki ◽  
H. Washioka ◽  
J. Mizoguchi

A vertebrate disk membrane is composed of 40 % lipids and 60 % proteins. Its fracture faces have been classed into the plasmic (PF) and exoplasmic faces (EF), complementary with each other, like those of most other types of cell membranes. The hypothesis assuming the PF particles as representing membrane-associated proteins has been challenged by serious questions if they in fact emerge from the crystalline formation or decoration effects during freezing and shadowing processes. This problem seems to be yet unanswered, despite the remarkable case of the purple membrane of Halobacterium, partly because most observations have been made on the replicas from a single face of specimen, and partly because, in the case of photoreceptor membranes, the conformation of a rhodopsin and its relatives remains yet uncertain. The former defect seems to be partially fulfilled with complementary replica methods.


1979 ◽  
Vol 88 (2) ◽  
pp. 856-858 ◽  
Author(s):  
V. E. Kagan ◽  
V. Z. Lankin ◽  
A. A. Shvedova ◽  
K. N. Novikov ◽  
S. K. Dobrina ◽  
...  

FEBS Letters ◽  
2001 ◽  
Vol 493 (2-3) ◽  
pp. 112-116 ◽  
Author(s):  
Joachim Bentrop ◽  
Markus Schillo ◽  
Gabriele Gerdon ◽  
Kazimir Draslar ◽  
Reinhard Paulsen

1974 ◽  
Vol 63 (2) ◽  
pp. 587-598 ◽  
Author(s):  
Izhak Nir ◽  
Michael O. Hall

The structure of lipid-depleted retinal rod photoreceptor membranes was studied by means of electron microscopy. Aldehyde-fixed retinas were exhaustively extracted with acetone, chloroform-methanol, and acidified chloroform-methanol. The effect of prefixation on the extractability of lipids was evaluated by means of thin-layer chromatography and fatty acid analysis. Prefixation with glutaraldehyde rendered 38% of the phospholipids unextractable, while only 7% were unextractable after formaldehyde fixation. Embedding the retina in a lipid-retaining, polymerizable glutaraldehyde-urea mixture allows a comparison of the interaction of OsO4 with lipid-depleted membranes and rod disk membranes which contain all their lipids. A decrease in electron density and a deterioration of membrane fine structure in lipid-depleted tissue are correlated with the extent of lipid extraction. These observations are indicative of the role of the lipid bilayer in the ultrastructural visualization of membrane structure with OsO4. Negatively stained thin sections of extracted tissue reveal substructures in the lipid-depleted rod membranes. These substructures are probably the opsin molecules which are the major protein component of retinal rod photoreceptor membranes.


Nature ◽  
1972 ◽  
Vol 236 (5345) ◽  
pp. 313-314 ◽  
Author(s):  
A. E. BLAUROCK ◽  
M. H. F. WILKINS

1974 ◽  
pp. 329-330
Author(s):  
F. J. M. Daemen ◽  
P. J. G. M. Breugel ◽  
S. L. Bonting

2020 ◽  
Vol 206 (6) ◽  
pp. 871-889
Author(s):  
Tatiana Feldman ◽  
Marina Yakovleva ◽  
Martta Viljanen ◽  
Magnus Lindström ◽  
Kristian Donner ◽  
...  

Abstract We have studied dark-adaptation at three levels in the eyes of the crustacean Mysis relicta over 2–3 weeks after exposing initially dark-adapted animals to strong white light: regeneration of 11-cis retinal through the retinoid cycle (by HPLC), restoration of native rhodopsin in photoreceptor membranes (by MSP), and recovery of eye photosensitivity (by ERG). We compare two model populations (“Sea”, Sp, and “Lake”, Lp) inhabiting, respectively, a low light and an extremely dark environment. 11-cis retinal reached 60–70% of the pre-exposure levels after 2 weeks in darkness in both populations. The only significant Lp/Sp difference in the retinoid cycle was that Lp had much higher levels of retinol, both basal and light-released. In Sp, rhodopsin restoration and eye photoresponse recovery parallelled 11-cis retinal regeneration. In Lp, however, even after 3 weeks only ca. 25% of the rhabdoms studied had incorporated new rhodopsin, and eye photosensitivity showed only incipient recovery from severe depression. The absorbance spectra of the majority of the Lp rhabdoms stayed constant around 490–500 nm, consistent with metarhodopsin II dominance. We conclude that sensitivity recovery of Sp eyes was rate-limited by the regeneration of 11-cis retinal, whilst that of Lp eyes was limited by inertia in photoreceptor membrane turnover.


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