title: The Tn antigen-specific lectin from ground ivy is an insecticidal protein with an unusual physiology.
abstract: Leaves of ground ivy (Glechoma hederacea) contain a lectin (called Gleheda) that is structurally and evolutionary related to the classical legume lectins. Screening of a population of wild plants revealed that Gleheda accounts for more than one-third of the total leaf protein in some clones, whereas it cannot be detected in other clones growing in the same environment. Gleheda is predominantly expressed in the leaves where it accumulates during early leaf maturation. The lectin is not uniformly distributed over the leaves but exhibits a unique localization pattern characterized by an almost exclusive confinement to a single layer of palisade parenchyma cells. Insect feeding trials demonstrated that Gleheda is a potent insecticidal protein for larvae of the Colorado potato beetle (Leptinotarsa decemlineata). Because Gleheda is not cytotoxic, it is suggested that the insecticidal activity is linked to the carbohydrate-binding specificity of the lectin, which as could be demonstrated by agglutination assays with different types of polyagglutinable human erythrocytes is specifically directed against the Tn antigen structure (N-acetylgalactosamine O-linked to serine or threonine residues of proteins).
authors.affiliation: Department of Molecular Biotechnology, Ghent University, Coupure Links 653, 9000 Gent, Belgium.
authors.forename: Weifang
authors.initials: W
authors.lastname: Wang
authors.forename: Bettina
authors.initials: B
authors.lastname: Hause
authors.forename: Willy J
authors.initials: WJ
authors.lastname: Peumans
authors.forename: Guy
authors.initials: G
authors.lastname: Smagghe
authors.forename: Anne
authors.initials: A
authors.lastname: Mackie
authors.forename: Robin
authors.initials: R
authors.lastname: Fraser
authors.forename: Els J M
authors.initials: EJ
authors.lastname: van Damme
mesh_terms: D000375:Aging; D000818:Animals; D000935:Antifungal Agents / Q000494:pharmacology; D015295:Antigens, Tumor-Associated, Carbohydrate / Q000378:metabolism*; D002460:Cell Line; D001517:Coleoptera / Q000187:drug effects / Q000254:growth & development / Q000502:physiology; D005247:Feeding Behavior / Q000187:drug effects; D006384:Hemagglutination / Q000187:drug effects; D006801:Humans; D007306:Insecticides / Q000378:metabolism / Q000494:pharmacology* / Q000633:toxicity; D019686:Lamiaceae / Q000737:chemistry*; D037102:Lectins / Q000378:metabolism / Q000494:pharmacology* / Q000633:toxicity; D051379:Mice; D018515:Plant Leaves / Q000737:chemistry
chemical_list: D000935:Antifungal Agents; D015295:Antigens, Tumor-Associated, Carbohydrate; D007306:Insecticides; D037102:Lectins; C040286:Tn antigen