Biosynthesis of the precursor of a soluble human insulin receptor ectodomain in insect Sf9 cells infected with a recombinant baculovirus.
In contrast to transfected mammalian cells, insect Sf9 cells infected with a recombinant Baculovirus inefficiently process and secrete a soluble derivative of the extracellular domain of the human insulin receptor. The high-mannose form of the receptor precursor that accumulates intracellularly is not grossly aberrant or malfolded, as its interaction with a diverse panel of monoclonal antibodies are comparable to secreted precursor and proteolytically processed receptor, both of which bear partially trimmed oligosaccharide chains. Thus the inefficient step in the biosynthesis of this protein in Sf9 cells is either at, or just preceding, the trimming of its high-mannose oligosaccharide chains.
Sissom
J F
JF
Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas 75235-9050.
Ellis
L
L
D000818:Animals; D000911:Antibodies, Monoclonal; D000918:Antibody Specificity; D016367:Baculoviridae / Q000378:metabolism*; D002460:Cell Line; D006801:Humans; D008358:Mannose / Q000737:chemistry; D009036:Moths / Q000378:metabolism* / Q000382:microbiology; D009844:Oligosaccharides / Q000737:chemistry; D011498:Protein Precursors / Q000096:biosynthesis*; D011972:Receptor, Insulin / Q000737:chemistry / Q000276:immunology / Q000378:metabolism*; D011995:Recombination, Genetic; D012995:Solubility
D000911:Antibodies, Monoclonal; D009844:Oligosaccharides; D011498:Protein Precursors; D011972:Receptor, Insulin; D008358:Mannose