Oligomerization is essential for transport of vesicular stomatitis viral glycoprotein to the cell surface

Using ts045, a temperature sensitive strain of Vesicular stomatitis virus, we show that oligomerization of G protein is a prerequisite for its transport from RER to the Golgi apparatus and for its subsequent maturation. While wild-type G forms an oligomer in the RER, ts045 G synthesized at the nonpermissive temperature does not. When the permissive temperature is reinstated, ts045 G forms an oligomer and moves to the Golgi. The state of oligomerization was determined by chemical cross-linking and by the ability of a microinjected monoclonal antibody specific for the carboxy-terminal five amino acids of the cytoplasmic tail of G to cause patching of G in intracellular membranes. We conclude that formation of an oligomer of G protein, probably a trimer, is necessary for G protein maturation.