title: Playing Modular Puzzle with Adhesion/Growth-Regulatory Galectins: Design and Testing of a Hybrid to Unravel Structure-Activity Relationships.
abstract: The potent multifunctionality of human galectins is based on their modular structure in a not yet fully understood manner. A strategy to dissect the contributions of individual sequence stretches to lectin activity is based on engineering variants of the natural proteins, which are composed of novel combinations of distinct parts. On proof-of-principle level, we here describe the design of a hybrid constituted by the N-terminal tail of chimera-type galectin-3 and the Nterminal carbohydrate recognition domain of tandem-repeat-type galectin-8, its production, purification and its serine phosphorylation characteristic for galectin- 3's tail. As measured for the respective parental proteins, its binding to (neo)glycoproteins is specific for β-galactosides and inhibitable by lactose, with KD-value closer to galectin-8 than galectin-3. Cell surface staining indicated similarity of the hybrid's reactivity to O-glycans and sensitivity for sialylation to respective properties of tandem-repeattype galectin-8 and its N-terminal domain. Applied as histochemical tool on tissue sections of murine jejunum and epididymis, intense lactose-inhibitable signals were recorded intracellularly, with a distribution profile akin to that of galectin-3. Tested as agglutinin, the hybrid was potent, excelling wild-type control galectins. The chimera-type design can thus serve as platform for tuning crosslinking activity.
authors.forename: Anna-Kristin
authors.initials: AK
authors.lastname: Ludwig
authors.forename: Sabine
authors.initials: S
authors.lastname: Vértesy
authors.forename: Malwina
authors.initials: M
authors.lastname: Michalak
authors.forename: Joachim C
authors.initials: JC
authors.lastname: Manning
authors.forename: Sabine
authors.initials: S
authors.lastname: Andre
authors.forename: Dieter
authors.initials: D
authors.lastname: Kubler
authors.forename: Jurgen
authors.initials: J
authors.lastname: Kopitz
authors.forename: Herbert
authors.initials: H
authors.lastname: Kaltner
authors.affiliation: Institute of Physiological Chemistry, Faculty of Veterinary Medicine, Ludwig-Maximilians- University Munich, Veterinarstr. 13, 80539 München, Germany.
authors.forename: Hans-Joachim
authors.initials: HJ
authors.lastname: Gabius
mesh_terms: D000373:Agglutinins / Q000378:metabolism; D000818:Animals; D001665:Binding Sites / Q000235:genetics; D004822:Epididymis / Q000378:metabolism*; D005697:Galactosides / Q000378:metabolism*; D037502:Galectin 3 / Q000235:genetics / Q000378:metabolism*; D037161:Galectins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D007583:Jejunum / Q000378:metabolism*; D007785:Lactose / Q000737:chemistry; D008297:Male; D051379:Mice; D010766:Phosphorylation; D011485:Protein Binding; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism*; D013194:Staining and Labeling; D013329:Structure-Activity Relationship
chemical_list: D000373:Agglutinins; D005697:Galactosides; D037502:Galectin 3; D037161:Galectins; C091991:LGALS8 protein, human; D011993:Recombinant Fusion Proteins; C007816:beta-galactoside; D007785:Lactose