Synthesis of soluble myelin-associated glycoprotein in insect and mammalian cells.
The myelin-associated glycoprotein (MAG) has an extracellular domain containing five sequences which are homologous to the immunoglobulin-fold motif. Adhesive interactions mediated by the MAG extracellular domain are involved in the development of the myelin sheath. The MAG cDNA has been modified to introduce a stop codon immediately before the transmembrane domain. Expression of the modified cDNA in insect cells and murine NIH-3T3 cells resulted in secretion of the soluble MAG extracellular domain. Treatment of soluble MAG with glycopeptidase F and endoglycosidase H showed significant differences in glycosylation for the insect and mammalian cell-expression systems. The soluble form of MAG has been purified from insect-cell supernatants by adsorption to a lentil-lectin support. The soluble MAG will provide a powerful new approach for studies of MAG-adhesive interactions during brain development.
Johnson
P W
PW
Department of Medical Genetics, University of Toronto, Toronto, Ont., Canada.
Attia
J
J
Richardson
C D
CD
Roder
J C
JC
Dunn
R J
RJ
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D050260:Carbohydrate Metabolism; D002460:Cell Line; D003062:Codon; D005813:Genes, Synthetic; D006031:Glycosylation; D015151:Immunoblotting; D007304:Insect Viruses / Q000235:genetics; D007313:Insecta / Q000166:cytology / Q000382:microbiology; D007700:Kinetics; D008322:Mammals; D008969:Molecular Sequence Data; D009185:Myelin Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D018992:Myelin-Associated Glycoprotein; D011401:Promoter Regions, Genetic; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000235:genetics / Q000302:isolation & purification; D013539:Simian virus 40 / Q000235:genetics; D012995:Solubility; D013045:Species Specificity; D013728:Terminator Regions, Genetic
D003062:Codon; D009185:Myelin Proteins; D018992:Myelin-Associated Glycoprotein; D011994:Recombinant Proteins