Nature 274, 487 - 490 (03 August 1978); doi:10.1038/274487a0

Glycosylation is not necessary for membrane insertion and cleavage of Semliki Forest virus membrane proteins

HENRIK GAROFF^* & RALPH T. SCHWARZ^†

^*European Molecular Biology Laboratory, Postfach 10 2209, D6900, Heidelberg, FRG
^†Institut für Virologie, Justus Liebig University, D6300 Giessen, FRG

RECENT translation studies in vitro ^1,2,33 have shown that the synthesis of membrane ectoproteins, like the glycoproteins of vesicular stomatitis virus (VSV) and Semliki Forest virus (SFV), (budding, enveloped viruses), occurs simultaneously with their insertion into membranes, their glycosylation and their proteolytic processing. We have studied the synthesis of SFV membrane proteins in infected cells treated with tunicamycin, which prevents glycosylation of proteins by inhibiting the formation of the lipid bound sugar intermediates needed for protein glycosylation³⁻⁵. We have found that glycosylation is not a prerequisite for correct insertion and cleavage of such membrane ectoproteins.

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