Oligomerization of glycolipid-anchored and soluble forms of the vesicular stomatitis virus glycoprotein.
The vesicular stomatitis virus glycoprotein forms noncovalently linked trimers in the endoplasmic reticulum before being transported to the Golgi apparatus. The experiments reported here were designed to determine if the extracellular domain of the glycoprotein contains structural information sufficient to direct trimer formation. To accomplish this, we generated a construct encoding G protein with the normal transmembrane and anchor sequences replaced with the sequence encoding 53 C-terminal amino acids from the Thy-1.1 glycoprotein. We show here that these sequences were able to specify glycolipid addition to the truncated G protein, probably after cleavage of 31 amino acids derived from Thy-1.1. The glycolipid-anchored G protein formed trimers and was expressed on the cell surface in a form that could be cleaved by phosphoinositol-specific phospholipase C. However, the rate of transport was reduced, compared with that of wild-type G protein. A second form of the G protein was generated by deletion of only the transmembrane and cytoplasmic domains. This mutant protein also formed trimers with relatively high efficiency and was secreted slowly from cells.
Crise
B
B
Department of Pathology, School of Medicine, Yale University, New Haven, Connecticut 06510-8023.
Ruusala
A
A
Zagouras
P
P
Shaw
A
A
Rose
J K
JK
D000118:Acetylglucosaminidase / Q000378:metabolism; D000595:Amino Acid Sequence; D001483:Base Sequence; D002499:Centrifugation, Density Gradient; D003062:Codon / Q000235:genetics; D004591:Electrophoresis, Polyacrylamide Gel; D006017:Glycolipids / Q000378:metabolism*; D006367:HeLa Cells / Q000378:metabolism; D006801:Humans; D007700:Kinetics; D046911:Macromolecular Substances; D017038:Mannosyl-Glycoprotein Endo-beta-N-Acetylglucosaminidase; D008562:Membrane Glycoproteins / Q000235:genetics*; D008969:Molecular Sequence Data; D015183:Restriction Mapping; D012995:Solubility; D014721:Vesicular stomatitis Indiana virus / Q000235:genetics*; D014759:Viral Envelope Proteins / Q000235:genetics* / Q000302:isolation & purification
D003062:Codon; C028391:G protein, vesicular stomatitis virus; D006017:Glycolipids; D046911:Macromolecular Substances; D008562:Membrane Glycoproteins; D014759:Viral Envelope Proteins; D000118:Acetylglucosaminidase; D017038:Mannosyl-Glycoprotein Endo-beta-N-Acetylglucosaminidase