The Journal of Cell Biology, Vol 97, 659-668, Copyright © 1983 by The Rockefeller University Press

ARTICLES

Modulation of glycosylation and transport of viral membrane glycoproteins by a sodium ionophore

FV Alonso-Caplen and RW Compans

Analysis of viral glycoprotein expression on surfaces of monensin- treated cells using a fluorescence-activated cell sorter (FACS) demonstrated that the sodium ionophore completely inhibited the appearance of the vesicular stomatitis virus (VSV) G protein on (Madin- Darby canine kidney) MDCK cell surfaces. In contrast, the expression of the influenza virus hemagglutinin (HA) glycoprotein on the surfaces of MDCK cells was observed to occur at high levels, and the time course of its appearance was not altered by the ionophore. Viral protein synthesis was not inhibited by monensin in either VSV- or influenza virus-infected cells. However, the electrophoretic mobilities of viral glycoproteins were altered, and analysis of pronase-derived glycopeptides by gel filtration indicated that the addition of sialic acid residues to the VSV G protein was impaired in monensin-treated cells. Reduced incorporation of fucose and galactose into influenza virus HA was observed in the presence of the ionophore, but the incompletely processed HA protein was cleaved, transported to the cell surface, and incorporated into budding virus particles. In contrast to the differential effects of monensin on VSV and influenza virus replication previously observed in monolayer cultures of MDCK cells, yields of both viruses were found to be significantly reduced by high concentrations of monensin in suspension cultures, indicating that cellular architecture may play a role in determining the sensitivity of virus replication to the drug. Nigericin, an ionophore that facilitates transport of potassium ions across membranes, blocked the replication of both influenza virus and VSV in MDCK cell monolayers, indicating that the ion specificity of ionophores influences their effect on the replication of enveloped viruses.
CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

• Watanabe, S., Imai, M., Ohara, Y., Odagiri, T. (2003). Influenza B Virus BM2 Protein Is Transported through the trans-Golgi Network as an Integral Membrane Protein. J. Virol. 77: 10630-10637 [Abstract] [Full Text]  
• Sun, A.-Q., Swaby, I'K., Xu, S., Suchy, F. J. (2001). Cell-specific basolateral membrane sorting of the human liver Na+-dependent bile acid cotransporter. Am. J. Physiol. Gastrointest. Liver Physiol. 280: G1305-G1313 [Abstract] [Full Text]  
• Roberts, P. C., Kipperman, T., Compans, R. W. (1999). Vesicular Stomatitis Virus G Protein Acquires pH-Independent Fusion Activity during Transport in a Polarized Endometrial Cell Line. J. Virol. 73: 10447-10457 [Abstract] [Full Text]  
• Arreaza, G., Brown, D. A. (1995). Sorting and Intracellular Trafficking of a Glycosylphosphatidylinositol-anchored Protein and Two Hybrid Transmembrane Proteins with the Same Ectodomain in Madin-Darby Canine Kidney Epithelial Cells. J. Biol. Chem. 270: 23641-23647 [Abstract] [Full Text]  
• van Meer, G, van 't Hof, W (1993). Epithelial sphingolipid sorting is insensitive to reorganization of the Golgi by nocodazole, but is abolished by monensin in MDCK cells and by brefeldin A in Caco-2 cells. J. Cell Sci. 104: 833-842 [Abstract]  

Home | Help | Feedback | Subscriptions | Archive | Search | Table of Contents