Model for Vesicular Stomatitis Virus

This study demonstrates that the glycoprotein of vesicular stomatitis virus clusters in the plasma membrane of infected Chinese hamster lung cells during morphogenesis and suggests that viral nucleocapsids are required for this clustering. A mutant virus (ts E-1) which is temperature sensitive for the synthesis of viral nucleocapsids but not viral membrane proteins was used. The surface distribution of the viral glycoprotein in cells infected by this virus was determined by a specific indirect immunoferritin stain. Early in infection at permissive temperatures, the glycoprotein was randomly distributed on membrane ghosts. Later, clusters of ferritin the size and shape of virus particles were seen. In contrast, ghosts prepared from virus-infected cells maintained at a restrictive temperature always had a random distribution of viral glycoprotein.Integral membrane proteins span the membranes with which they are associated and may participate in significant molecular interactions on both sides of the membrane. In many cases, these proteins are freely diffusible in the plane of the membrane (37). An increasing number of membrane proteins, however, are found to be distributed over the surface of the cell in a nonrandom fashion. For example, Ash et al. (1) have shown that several antibody-patched integral membrane proteins are arranged in linear arrays on the surface of cultured fibroblasts, specific receptor molecules are frequently localized in defined regions of the membrane, and viral glycoproteins of lipid-containing viruses are localized in regions of the membrane active in virus assembly (8). The molecular interactions which lead to the nonrandom distribution of integral proteins are currently under active study in a number of laboratories. Evidence is accumulating which indicates that the linear arrays of membrane proteins visible on the surface of fibroblasts result from interactions of domains of these proteins present on the cytoplasmic surface with elements of the cytoskeleton (1, 14,22). In the case of the best-studied receptor system, that of the low-density lipoproteins, the molecules appear to be inserted into the membrane at random sites and then to migrate laterally in the plane of the membrane until they reach a "coated pit." A domain of the receptor presumed to be on the cytoplasmic side t Present address:

Section: Discussionmentioning

confidence: 99%

Assembly of vesicular stomatitis virus: distribution of the glycoprotein on the surface of infected cells

Jacobs¹,

Penhoet²

1982

“…The earlier designation of S (for surface) protein (22) is incorrect and should be abandoned. The hypothesis has been advanced that the M protein is the matrix protein that serves to bind the ribonucleocapsid to the VS viral envelope (6). In this respect, as well as others, the rhabdovirus M protein is quite similar to, but not interchangeable with, the single matrix protein of paramyxoviruses (16).…”

mentioning

confidence: 97%

Classification of Rhabdovirus Proteins: a Proposal

Wagner

Prevec

Brown

et al. 1972

Self Cite

180

“…The morphological alterations of the viral membrane induced by filipin and amphotericin B are of interest in considering the mechanism that determines glycoprotein arrangement on the virion surface. A model of the structure of the VS viral envelope has been proposed, in which surface glycoproteins are regularly arranged on a hexagonal lattice of underlying membrane protein (6). Because of the stoichiometric relationship between bound filipin and membrane cholesterol and the known sterol requirement for filipin action, it is likely that the morphological alteration in the membrane results from the formation of filipin-cholesterol complexes.…”

Section: Discussionmentioning

confidence: 99%

Effects of Filipin on the Structure and Biological Activity of Enveloped Viruses

Majuk

Bittman

Landsberger

et al. 1977

The interaction of the polyene antibiotic filipin with membrane-bound cholesterol in vesicular stomatitis (VS), influenza, and Rauscher leukemia virions was studied. Exposure of virions to filipin resulted in a series of depressions and ridges in the envelope of VS virions, with a periodicity of 15 to 20 nm perpendicular to the long axis of the particle; similar morphological alterations were observed in negatively stained preparations, in thin-sectioned virions, and in protease-treated virions that lack surface glycoproteins. This morphological effect was specific for filipin, since the envelopes of VS virions that had been treated with another polyene antibiotic, amphotericin B, exhibited markedly different morphology. Morphological alterations induced by filipin in influenza and Rauscher leukemia virions differed from those seen in VS virions. The infectivity of filipin-treated VS virions was reduced up to 500-fold, whereas influenza virions were resistant to filipin treatment. Incorporation of filipin into the virions was demonstrated, and no release of either lipids or proteins from virions was detected after filipin treatment. A stoichiometry of approximately 1 mol of bound filipin per mol of cholesterol was found in both intact and protease-treated VS virions. The equilibrium dissociation constant for filipin-cholesterol interaction was approximately 74-fold larger in intact than in protease-treated VS virions. The initial rate of association of filipin with cholesterol in intact virions was slower than that in protease-treated particles. The fluidity of lipids in VS viral membranes, as probed by a stearic acid derivative spin label, was markedly reduced when either intact or protease-treated virions were treated with filipin.