title: Pre-B cell receptor binding to galectin-1 modifies galectin-1/carbohydrate affinity to modulate specific galectin-1/glycan lattice interactions.
abstract: Galectins are glycan-binding proteins involved in various biological processes including cell/cell interactions. During B-cell development, bone marrow stromal cells secreting galectin-1 (GAL1) constitute a specific niche for pre-BII cells. Besides binding glycans, GAL1 is also a pre-B cell receptor (pre-BCR) ligand that induces receptor clustering, the first checkpoint of B-cell differentiation. The GAL1/pre-BCR interaction is the first example of a GAL1/unglycosylated protein interaction in the extracellular compartment. Here we show that GAL1/pre-BCR interaction modifies GAL1/glycan affinity and particularly inhibits binding to LacNAc containing epitopes. GAL1/pre-BCR interaction induces local conformational changes in the GAL1 carbohydrate-binding site generating a reduction in GAL1/glycan affinity. This fine tuning of GAL1/glycan interactions may be a strategic mechanism for allowing pre-BCR clustering and pre-BII cells departure from their niche. Altogether, our data suggest a novel mechanism for a cell to modify the equilibrium of the GAL1/glycan lattice involving GAL1/unglycosylated protein interactions.
authors.affiliation: 1] Laboratoire d'Ingénierie des Systèmes Macromoléculaires, CNRS UMR7255, 13402 Marseille, France [2] Aix-Marseille Université, UM105, 13284 Marseille cedex 07, France.
authors.forename: Jeremy
authors.initials: J
authors.lastname: Bonzi
authors.affiliation: 1] Aix-Marseille Université, UM105, 13284 Marseille cedex 07, France [2] Institut de Microbiologie de la Méditerranée, CNRS FR3479, 13402 Marseille, France.
authors.forename: Olivier
authors.initials: O
authors.lastname: Bornet
authors.affiliation: 1] Aix-Marseille Université, UM105, 13284 Marseille cedex 07, France [2] Centre de Recherche en Cancérologie de Marseille, Institut Paoli-Calmettes, CNRS UMR 7258, INSERM U1068, 13273 Marseille, France.
authors.forename: Stephane
authors.initials: S
authors.lastname: Betzi
authors.affiliation: Department of Chemistry, Biomedical Chemistry Institute, New York University, 100 Washington Square East, Room 1001, New York, New York 10003, USA.
authors.forename: Brian T
authors.initials: BT
authors.lastname: Kasper
authors.affiliation: Department of Chemistry, Biomedical Chemistry Institute, New York University, 100 Washington Square East, Room 1001, New York, New York 10003, USA.
authors.forename: Lara K
authors.initials: LK
authors.lastname: Mahal
authors.affiliation: 1] Aix-Marseille Université, UM105, 13284 Marseille cedex 07, France [2] Centre d'Immunologie de Marseille-Luminy, Faculté des Sciences de Luminy, INSERM U1104, CNRS UMR7280, 13288 Marseille, France.
authors.forename: Stephane J
authors.initials: SJ
authors.lastname: Mancini
authors.affiliation: 1] Aix-Marseille Université, UM105, 13284 Marseille cedex 07, France [2] Centre d'Immunologie de Marseille-Luminy, Faculté des Sciences de Luminy, INSERM U1104, CNRS UMR7280, 13288 Marseille, France.
authors.forename: Claudine
authors.initials: C
authors.lastname: Schiff
authors.affiliation: 1] Laboratoire d'Ingénierie des Systèmes Macromoléculaires, CNRS UMR7255, 13402 Marseille, France [2] Aix-Marseille Université, UM105, 13284 Marseille cedex 07, France.
authors.forename: Corinne
authors.initials: C
authors.lastname: Sebban-Kreuzer
authors.affiliation: 1] Laboratoire d'Ingénierie des Systèmes Macromoléculaires, CNRS UMR7255, 13402 Marseille, France [2] Aix-Marseille Université, UM105, 13284 Marseille cedex 07, France.
authors.forename: Francoise
authors.initials: F
authors.lastname: Guerlesquin
authors.affiliation: 1] Laboratoire d'Ingénierie des Systèmes Macromoléculaires, CNRS UMR7255, 13402 Marseille, France [2] Aix-Marseille Université, UM105, 13284 Marseille cedex 07, France.
authors.forename: Latifa
authors.initials: L
authors.lastname: Elantak
mesh_terms: D000818:Animals; D050260:Carbohydrate Metabolism; D002460:Cell Line; D018604:Epitope Mapping; D037483:Galectin 1 / Q000378:metabolism*; D006801:Humans; D051379:Mice; D011134:Polysaccharides / Q000378:metabolism*; D054420:Pre-B Cell Receptors / Q000378:metabolism*; D054448:Precursor Cells, B-Lymphoid / Q000378:metabolism
chemical_list: D037483:Galectin 1; D011134:Polysaccharides; D054420:Pre-B Cell Receptors