Monensin and FCCP Inhibit the Intracellular Transport of Alphavirus Membrane Glycoproteins

• Published in: The Journal of cell biology Vol. 87; no. 3; pp. 783 - 791
• Main Authors: Kääriäinen, L., Hashimoto, K., Saraste, J., Virtanen, I., Penttinen, K.
• Format: Journal Article
• Language: English
• Published: United States Rockefeller University Press 01.12.1980; The Rockefeller University Press
• Subjects: Alphavirus; Animals; Biological Transport - drug effects; Carbonyl Cyanide p-Trifluoromethoxyphenylhydrazone - pharmacology; Cell Membrane - metabolism; Cell membranes; Cells; Cells, Cultured; Chick Embryo; Cultured cells; Endoplasmic Reticulum - metabolism; Fibroblasts; Furans - pharmacology; Glycoproteins; Glycoproteins - metabolism; Golgi apparatus; Golgi Apparatus - metabolism; Hepatocytes; Membrane glycoproteins; Membrane proteins; Membrane Proteins - metabolism; Monensin - pharmacology; Nitriles - pharmacology; Plasma cells; Viral Proteins - metabolism; Viruses
• ISSN: 0021-9525; 1540-8140
• DOI: 10.1083/jcb.87.3.783

Temperature-sensitive mutants of Semliki Forest virus (SFV) and Sindbis virus (SIN) were used to study the intracellular transport of virus membrane glycoproteins in infected chicken embryo fibroblasts. When antisera against purified glycoproteins and125I-labeled protein A from Staphylococcus aureus were used, only small amounts of virus glycoproteins were detected at the surface of SFV ts-1 and SIN Ts-10 infected cells incubated at the restrictive temperature (39°C). When the mutant-infected cells were shifted to the permissive temperature (28°C), in the presence of cycloheximide, increasing amounts of virus glycoproteins appeared at the cell surface from 20 to 80 min after the shift. Both monensin (10 μM) and carbonylcyanide-p-trifluoromethoxyphenylhydrazone (FCCP; 10-20 μM) inhibited the appearance of virus membrane glycoproteins at the cell surface. Vinblastine sulfate (10 μg/ml) inhibited the transport by ∼50%, whereas cytochalasin B (1 μg/ml) had only a marginal effect. Intracellular distribution of virus glycoproteins in the mutant-infected cells was visualized in double-fluorescence studies using lectins as markers for endoplasmic reticulum and Golgi apparatus. At 39°C, the virus membrane glycoproteins were located at the endoplasmic reticulum, whereas after shift to 28°C, a bright juxtanuclear reticular fluorescence was seen in the location of the Golgi apparatus. In the presence of monensin, the virus glycoproteins could migrate to the Golgi apparatus, although transport to the cell surface did not take place. When the shift was carried out in the presence of FCCP, negligible fluorescence was seen in the Golgi apparatus and the glycoproteins apparently remained in the rough endoplasmic reticulum. A rapid inhibition in the accumulation of virus glycoproteins at the cell surface was obtained when FCCP was added during the active transport period, whereas with monensin there was a delay of ∼10 min. These results suggest a similar intracellular pathway in the maturation of both plasma membrane and secretory glycoproteins.