A rhodopsin—lipid—water lamellar system: Its characterisation by x‐ray diffraction and electron microscopy

Chabre, Marc; Cavaggioni, Andrea; Osborne, Howard Beverley; Gulik-Krzywicki, T.; Olive, Jacqueline

doi:10.1016/0014-5793(72)80572-6

Cited by 33 publications

(6 citation statements)

References 11 publications

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“…Visual pigment is an intrinsic component of both discs and ROS plasma membrane (3,23) where it gives rise to a relatively uniform distribution of IMP with a density of ^-4,500-6,000/,um2 in PF leaflets (2,13,14,25,27,41) . The IMP distribution in ROS probably reflects the presence of visual pigment within the lipid bilayer, because a similar freezefracture picture is obtained from artificial lipid bilayers containing rhodopsin (11,12,22) . Estimates of the number of rhodopsin molecules per square micrometer of disc membrane, however, are generally four to five times higher than the number of IMP (12,14), indicating that the IMP and rhodopsin do not correspond on a one-to-one basis (14,25) .…”

Section: Outer Segment Membranes In Rods and Conesmentioning

confidence: 54%

Membrane assembly in retinal photoreceptors I. Freeze-fracture analysis of cytoplasmic vesicles in relationship to disc assembly.

Besharse¹,

Pfenninger²

1980

The Journal of Cell Biology

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To study precursor-product relationships between cytoplasmic membranes of the inner segment of photoreceptors and the continually renewed outer disc membrane, we have compared the density and size distribution of intramembrane particles (IMP) in various membrane compartments of freeze-fractured photoreceptor inner and outer segments . Both rod and cone outer segments of Xenopus laevis are characterized by a relatively uniform distribution of 4,400-4,700 IMP/ IAm2 in P-face (PF) leaflets of disc membranes . A similar distribution of IMP is found in the outer segment plasma membrane, the ciliary plasma membrane, and in the plasma membrane of the inner segment in the immediate periciliary region . In each case the size distribution of IMP can be characterized as unimodal with a mean diameter of -10 nm . PF leaflets of endoplasmic reticulum, Golgi complex, and vesicles near the cilium have IMP with a size distribution like that in the cilium and outer segment, but with an average density of^-2,000/p,m 2 . In contrast, IMP are smaller in average size (^-7 .5 nm) in PF leaflets of inner segment plasma membrane, exclusive of the periciliary region . The similarity of size distribution of IMP in inner segment cytoplasmic membranes and those within the plasmalemma of the cilium and outer segment suggest a precursor-product relationship between the two systems. The structure of the vesicle-rich periciliary region and the segregation of IMP with different size distributions in this region suggest that components destined for incorporation into the outer segment exist as preformed membrane packages (vesicles) which fuse with the inner segment plasma membrane in the periciliary region . Subsequently, membrane components may be transferred to forming discs of the outer segment via the ciliary plasma membrane .Vertebrate photoreceptors are composed of a photosensitive outer segment (ROS), an inner segment that contains the cell's metabolic machinery (i .e ., endoplasmic reticulum, Golgi complex, ribosomes, mitochondria), and a synaptic terminal at which contacts with second-order neurons of the retina are made . The photosensitive outer segment (Fig . 1) is connected to the inner segment by a modified, nonmotile cilium (42), and consists of a series of discrete membranous discs that are apparently derived from the plasma membrane in the region of the connecting cilium (32) . The process of disc assembly, which continues throughout the life of the cell (49, 50), is widely believed to involve infolding of ROS plasma membrane (32) or protrusion of ciliary plasma membrane (1) . Either

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Section: Outer Segment Membranes In Rods and Conesmentioning

confidence: 54%

Membrane assembly in retinal photoreceptors I. Freeze-fracture analysis of cytoplasmic vesicles in relationship to disc assembly.

Besharse¹,

Pfenninger²

1980

The Journal of Cell Biology

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“…The dispersions were made by dissolving the lipid in CHC13, evaporating the solvent under nitrogen and adding D20 95%. Bovine ROS were obtained using the method of Chabre et al (10), from which purified and lyophilized membranes were obtained. They were then buffered with Tris-HCI 2 mM in D20 95% at pH -8 and nitrogen saturated to minimize oxidative damage to the polyunsaturated fatty acids.…”

Section: Methodsmentioning

confidence: 99%

1H-NMR Relaxation Investigation of Water Bound to Bovine Rod Outer Segment Disk Membranes

Gaggelli¹,

Niccolai²,

Valensin³

1982

Biophysical Journal

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Spin-lattice relaxation times T(1) in deuterated aqueous dispersions of lecithin and rod outer segment disk membranes were measured at various concentrations and temperatures. Fast chemical exchange between two loosely defined phases of water molecules was shown to fit the data, allowing the dynamic features of "bound" water and the hydration of the biological membrane to be evaluated. The state of the water was shown to be also involved in vision physiology.

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“…Hong and Hubbell (1972) and Applebury, Zuckerman, Lamola and Jovin (1974) have reported the incorporation of purified rhodopsin, free of disc membrane lipids, into small membrane vesicles of defined lipid composition. Chabre, Cavaggioni, Osborne, Gulik-Krzywicki and Olive (1972) and Darszon and Montal (1976), on the other hand, have reported the incorporation into membrane vesicles of a detergent extract of purified outer segments, rich in rhodopsin and disc membrane lipids. These vesicle membranes are excellent subjects for structural (Chabre et al, 1972;Chen & Hubbell, 1973), tracer flux (Darszon & Montal, 1976) and spectroscopic (Hong & Hubbell, 1972 ;Hong & Hubbell, 1973 ;Applebury et al, 1974) studies.…”

mentioning

confidence: 96%

“…Chabre, Cavaggioni, Osborne, Gulik-Krzywicki and Olive (1972) and Darszon and Montal (1976), on the other hand, have reported the incorporation into membrane vesicles of a detergent extract of purified outer segments, rich in rhodopsin and disc membrane lipids. These vesicle membranes are excellent subjects for structural (Chabre et al, 1972;Chen & Hubbell, 1973), tracer flux (Darszon & Montal, 1976) and spectroscopic (Hong & Hubbell, 1972 ;Hong & Hubbell, 1973 ;Applebury et al, 1974) studies. Unfortunately, their experimental use is limited because the intravesicular compartment is small and not directly accessible to measurements of solute concentrations or electrical parameters.…”

mentioning

confidence: 96%

Formation, structure, and spectrophotometry of air-water interface films containing rhodopsin

Korenbrot

Pramik

1977

J. Membrain Biol.

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Summary. Air-water interface films of cattle rhodopsin and defined lipids are formed without the use of organic solvents by a method in which vesicle membranes consisting of egg phosphatidyl choline and purified rhodopsin are osmotically shocked at the interface. Lipid and protein molecules organize as insoluble films at the interface. The structure of these films varies with the lipid to protein mole ratio of the source vesicle membranes. Electron microscopic observations reveal that films formed with membranes of 150:1 mole ratio consist of nonoverlapping, randomly distributed vesicle membrane fragments separated by a lipid monolayer. These membrane fragments exist as single sheets on the water surface and occupy approximately 35% of this surface. Essentially all the rhodopsin molecules at the interface are spectroscopically intact and are contained within the membrane fragments. The visible absorption spectrum of the interface films is identical to that of suspensions of rod disc membranes. Moreover, flash illumination of rhodopsin in air-dried multilayers formed from the interface films results in the formation of a stable Metarhodopsin I intermediate (2max ~--480 rim) which can be fully bleached by increasing the relative humidity of the multilayers or can be photoconverted into rhodopsin and, presumably, isorhodopsin. Furthermore, rhodopsin is chemically regenerable at the air-water interface. Bleached rhodopsin can generate dark rhodopsin at the interface in the presence of ll-cis retinal in the aqueous subphase. Thus, the spectroscopic structure and the chemical regenerability function of rhodopsin in these interface films are indistinguishable from those exhibited by the protein in intact rod disc membranes.

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A rhodopsin—lipid—water lamellar system: Its characterisation by x‐ray diffraction and electron microscopy

Cited by 33 publications

References 11 publications

Membrane assembly in retinal photoreceptors I. Freeze-fracture analysis of cytoplasmic vesicles in relationship to disc assembly.

Membrane assembly in retinal photoreceptors I. Freeze-fracture analysis of cytoplasmic vesicles in relationship to disc assembly.

1H-NMR Relaxation Investigation of Water Bound to Bovine Rod Outer Segment Disk Membranes

Formation, structure, and spectrophotometry of air-water interface films containing rhodopsin

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