Structural requirements of a membrane-spanning domain for protein anchoring and cell surface transport.
The membrane-spanning domain of the vesicular stomatitis virus glycoprotein (G) contains 20 uncharged and mostly hydrophobic amino acids. We created DNAs specifying G proteins with shortened transmembrane domains, by oligonucleotide-directed mutagenesis. Expression of these DNAs showed that G proteins containing 18, 16, or 14 amino acids of the original transmembrane domain assumed a transmembrane configuration and were transported to the cell surface. G proteins containing only 12 or 8 amino acids of this domain also spanned intracellular membranes, but their transport was blocked within a Golgi-like region in the cell. A G protein completely lacking the membrane-spanning domain accumulated in the endoplasmic reticulum and was secreted slowly. These experiments indicate that the size of the transmembrane domain is critical not only for membrane anchoring, but also for normal cell surface transport.
D000818:Animals; D001692:Biological Transport; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism*; D004721:Endoplasmic Reticulum / Q000378:metabolism; D005455:Fluorescent Antibody Technique; D006026:Glycoside Hydrolases / Q000378:metabolism; D006056:Golgi Apparatus / Q000378:metabolism; D017038:Mannosyl-Glycoprotein Endo-beta-N-Acetylglucosaminidase; D008562:Membrane Glycoproteins; D008565:Membrane Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D019308:Palmitic Acid; D010169:Palmitic Acids / Q000378:metabolism; D010957:Plasmids; D014759:Viral Envelope Proteins; D014764:Viral Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism*
C028391:G protein, vesicular stomatitis virus; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D010169:Palmitic Acids; D014759:Viral Envelope Proteins; D014764:Viral Proteins; D019308:Palmitic Acid; D006026:Glycoside Hydrolases; D017038:Mannosyl-Glycoprotein Endo-beta-N-Acetylglucosaminidase