Characterization of Poliovirus Conformational Alteration Mediated by Soluble Cell Receptors

doi:10.1006/viro.1993.1621

Virology

Volume 197, Issue 1, November 1993, Pages 501-505

https://doi.org/10.1006/viro.1993.1621 Get rights and content

Abstract

Soluble extracts of Spodoptera frugiperda cells expressing the poliovirus receptor (PVR) induce the native poliovirus (PV) to "A" particle conformational change (J. Virol. 64, 4697-4702). We describe the variables that regulate this passage and study the suitability of solubilized PVR both for use as an in vitro system to characterize the receptor-mediated conformational alteration and for the production of large amounts of altered virus for structural analysis. PVR seems to function in a stoichiometric fashion and the A particles produced appear as intact, stain excluding, spherical structures by electron microscopy, regardless of the extensive proteolysis of the capsid protein VP 1, which takes place during the conversion. The products obtained, time course, and temperature and ionic strength dependence of the alteration of PV by the solubilized PVR are indistinguishable from those of the alteration that leads to productive infection in cultured cells. Therefore, solubilized PVR may provide a convenient in vitro system for further characterization of the cell entry process.

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Short CommunicationsCharacterization of Poliovirus Conformational Alteration Mediated by Soluble Cell Receptors

Abstract

Short Communications
Characterization of Poliovirus Conformational Alteration Mediated by Soluble Cell Receptors