title: Hematopoietic growth factor glycosylation. Multiple forms of chicken myelomonocytic growth factor.
abstract: The production of chicken myelomonocytic growth factor (cMGF) can be rapidly induced by bacterial lipopolysaccharide from the macrophage cell line HD11. Immunoprecipitation analysis of lipopolysaccharide-induced HD11 cells labeled with various radioactive precursors showed the secretion of a variety of cMGF forms. The precursor-product relationships of the different cMGF forms were studied by pulse-chase experiments, by long-term metabolic labeling in the presence or absence of glycosylation- and oligosaccharide-processing inhibitors, as well as by glycosidase treatment of immunoprecipitates. Our results show that the half-time for intracellular processing/secretion is less than 10 min, making cMGF one of the most rapidly processed proteins. The different forms of the factor are generated from a 24-kDa polypeptide precursor by co- and post-translational acquisition of one or two N-linked oligosaccharides and by O-linked glycosylation. In addition, a fraction of cMGF is modified by long chain, chondroitinase-sensitive, sulfated glycans. This modification is tunicamycin-sensitive, suggesting that the sulfated glycans are attached to N-linked rather than to O-linked oligosaccharides.
authors.affiliation: Differentiation Programme, European Molecular Biology Laboratory, Heidelberg, Federal Republic of Germany.
authors.forename: A
authors.initials: A
authors.lastname: Leutz
authors.forename: H
authors.initials: H
authors.lastname: Beug
authors.forename: C
authors.initials: C
authors.lastname: Walter
authors.forename: T
authors.initials: T
authors.lastname: Graf
mesh_terms: D000818:Animals; D002460:Cell Line; D002645:Chickens; D006026:Glycoside Hydrolases; D006031:Glycosylation; D006133:Growth Substances / Q000096:biosynthesis / Q000378:metabolism*; D016298:Hematopoietic Cell Growth Factors; D006412:Hematopoietic Stem Cells / Q000378:metabolism*; D007700:Kinetics; D008070:Lipopolysaccharides / Q000494:pharmacology; D008264:Macrophages / Q000378:metabolism
chemical_list: D006133:Growth Substances; D016298:Hematopoietic Cell Growth Factors; D008070:Lipopolysaccharides; D006026:Glycoside Hydrolases