title: Lectin-like characteristics of recombinant human interleukin-1beta recognizing glycans of the glycosylphosphatidylinositol anchor.
abstract: We found that 35S-labeled recombinant human interleukin-1beta (rhIL-1beta) binds phosphatidylinositol-specific phospholipase C-treated human placental alkaline phosphatase, phosphatidylinositol-specific phospholipase C-treated trypanosome surface variant glycoproteins, and urinary uromodulin immobilized on plates or immobilized on CNBr-activated Sepharose 4B. The interaction between rhIL-1beta and these glycoproteins was lectin-like, since it was inhibited in the presence of specific saccharides, i.e. mannose 6-phosphate or synthetic Ac-NH.CH2.CH2. PO4--->6Manalpha1-->(+/-2Manalpha1-->+/-6Manalpha1-->) propyl at about 1 microM. On the other hand, a wide variety of compounds including biantennary sugar chains derived from these glycoproteins as well as ethanolamine phosphate, inositol phosphate, mannose 6-sulfate, mannose 1-phosphate, glucose 6-phosphate, and mannitol 6-phosphate did not show any inhibitory effect at concentrations up to 1 mM. These results indicate that rhIL-1beta interacts with these glycoproteins via the mannose 6-phosphate diester of glycans on the glycosylphosphatidylinositol (GPI) anchor. Furthermore, when monolayers of polarized Madin-Darby canine kidney cells on polycarbonate filter membranes were incubated with 35S-rhIL-1beta in either the apical or basolateral chamber, 35S-interleukin-1beta was found to bind specifically to the apical membranes with a Ka value of 4.6 x 10(7) M-1, and the specific interaction was inhibited by 1 microM mannose 6-phosphate. Since the mannose 6-phosphate diester moiety exists only in the GPI glycans on plasma membranes, it was evident that interleukin-1beta can directly interact with the mannose 6-phosphate diester component of the intact glycan of GPI anchors on plasma membranes.
authors.affiliation: Department of Biochemistry, Sasaki Institute, Kanda-Surugadai, Chiyoda-ku, Tokyo 101, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Fukushima
authors.forename: S
authors.initials: S
authors.lastname: Hara-Kuge
authors.forename: T
authors.initials: T
authors.lastname: Ohkura
authors.forename: A
authors.initials: A
authors.lastname: Seko
authors.forename: H
authors.initials: H
authors.lastname: Ideo
authors.forename: T
authors.initials: T
authors.lastname: Inazu
authors.forename: K
authors.initials: K
authors.lastname: Yamashita
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism*; D000818:Animals; D001665:Binding Sites; D002240:Carbohydrate Sequence; D002460:Cell Line; D004285:Dogs; D005260:Female; D017261:Glycosylphosphatidylinositols / Q000378:metabolism*; D006801:Humans; D007375:Interleukin-1 / Q000737:chemistry / Q000378:metabolism*; D007700:Kinetics; D037102:Lectins; D008360:Mannosephosphates / Q000494:pharmacology; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000378:metabolism / Q000494:pharmacology; D043265:Phosphatidylinositol Diacylglycerol-Lyase; D054801:Phosphoinositide Phospholipase C; D010727:Phosphoric Diester Hydrolases / Q000378:metabolism; D010920:Placenta / Q000201:enzymology; D011134:Polysaccharides / Q000737:chemistry / Q000378:metabolism*; D011247:Pregnancy; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D014347:Trypanosoma brucei gambiense; D014643:Variant Surface Glycoproteins, Trypanosoma / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D017261:Glycosylphosphatidylinositols; D007375:Interleukin-1; D037102:Lectins; D008360:Mannosephosphates; D009844:Oligosaccharides; D011134:Polysaccharides; D011994:Recombinant Proteins; D014643:Variant Surface Glycoproteins, Trypanosoma; C027693:mannose-6-phosphate; D000469:Alkaline Phosphatase; D010727:Phosphoric Diester Hydrolases; D054801:Phosphoinositide Phospholipase C; D043265:Phosphatidylinositol Diacylglycerol-Lyase