title: Galectins: their network and roles in immunity/tumor growth control.
abstract: One route of realizing the information of glycans involves endogenous receptors (lectins). Occurrence at branch ends renders galactosides particularly accessible. Thus, they are suited for such a recognition process. Fittingly, these epitopes serve as physiological ligands. The ga(lactoside-binding) lectins share the β-sandwich fold with a sequence signature around a central tryptophan residue besides this specificity. Three modes of presentation of the carbohydrate recognition domain are known for galectins, and genome monitoring from fungi to mammals discloses that galectins form a network. The extent of its complexity varies considerably between organisms, for chicken reaching seven proteins, more for mammals. The current status of network analysis reveals overlapping and distinct expression profiles. Matching intra- and extracellular galectin presence, they have a broad range of functions at each site depending on their specific counterreceptor(s), with the possibility even for functional antagonism between family members. Orchestration of expression of galectin, the cognate glycan, its scaffold (protein or sphingolipid) and spatial aspects of glycoconjugate presentation has been detected to lead to growth regulation of immune and tumor cells. To delineate the factors that underlie the specificity of a galectin for its counterreceptor(s) in the cellular context and the details of structure-activity relationships by comparatively analyzing natural and rationally engineered proteins is the main challenge for ongoing research.
authors.affiliation: Institute of Physiological Chemistry, Faculty of Veterinary Medicine, Ludwig-Maximilians-University Munich, 80539, Munich, Germany.
authors.forename: Herbert
authors.initials: H
authors.lastname: Kaltner
authors.affiliation: Karl Chiari Lab for Orthopaedic Biology, Department of Orthopaedics, Medical University of Vienna, 1090, Vienna, Austria.
authors.forename: Stefan
authors.initials: S
authors.lastname: Toegel
authors.affiliation: Institute of Physiological Chemistry, Faculty of Veterinary Medicine, Ludwig-Maximilians-University Munich, 80539, Munich, Germany.
authors.forename: Gabriel García
authors.initials: GG
authors.lastname: Caballero
authors.affiliation: Institute of Physiological Chemistry, Faculty of Veterinary Medicine, Ludwig-Maximilians-University Munich, 80539, Munich, Germany.
authors.forename: Joachim C
authors.initials: JC
authors.lastname: Manning
authors.affiliation: Department of Pharmacology, Physiology and Neurosciences, Rutgers - The State University of New Jersey, New Jersey Medical School, Newark, NJ, 07103, USA.
authors.forename: Robert W
authors.initials: RW
authors.lastname: Ledeen
authors.affiliation: Institute of Physiological Chemistry, Faculty of Veterinary Medicine, Ludwig-Maximilians-University Munich, 80539, Munich, Germany. gabius@tiph.vetmed.uni-muenchen.de.
authors.forename: Hans-Joachim
authors.initials: HJ
authors.lastname: Gabius
mesh_terms: D037161:Galectins / Q000276:immunology*; D006801:Humans; D007109:Immunity; D009369:Neoplasms / Q000276:immunology* / Q000503:physiopathology
chemical_list: D037161:Galectins
keywords: Adhesion; Apoptosis; Galectin; Glycosyltransferase; Lectin; Proliferation