IBYME   02675
INSTITUTO DE BIOLOGIA Y MEDICINA EXPERIMENTAL
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Helja, a sunflower Jacalin-Related Lectin, demonstrates preference for high mannose N-glycans
Autor/es:
DEL RIO, MARIANELA; PINEDO, MARCELA; MARIÑO, KARINA VALERIA; CUTINE, ANABELA; TICCHI, J; DE LA CANAL, LAURA; REGENTE, MARIANA; RABINOVICH, GABRIEL A.
Lugar:
Villa General Belgrano, Cordoba
Reunión:
Simposio; Segundo Simposio Argentino de Glicobiologia GlycoAr 2016; 2016
Institución organizadora:
IBYME/ CIQUIBIC/ Fundacion Leloir
Resumen:
Lectins are carbohydrate-binding proteins with high specificity for a variety of glycoconjugate sugar motifs. Jacalin-related lectins (JRLs) encompass cytosolic, nuclear and vacuolar members displaying the jacalin domain in one or more copies. Helianthus annuus jacalin (Helja) is a recently identified JRL purified from sunflower seeds and bioinformatic analyses predicted a mannose-binding lectin domain. This lectin inhibits the growth of pathogenic fungi containing surface mannans such as Candida albicans. The aim of this work is to characterize the ligand binding preferences of this lectin by optimizinga solid phase assay to measure lectin-ligand interactions. Working with Helja and its biotinylated form, we found that this lectin shows strong affinity to high-mannose structures present in RNase B, while it displays very weak interactions with de-sialylated complex N-glycans in asialofetuin. Next, we assessed the inhibitory capacity of monovalent ligands in competition with these immobilized glycoproteins. Methyl-α-mannoside exhibited the highest inhibition of Helja binding to RNase B (IC50 3,2mM), whereas decreased inhibitory capacity was observed for D-mannose (IC50 16,1mM). D-galactose and D-lactose showedalmost no interaction with Helja. This work contributes to the functional characterization of this recently described lectin, confirming its preference for high mannose N-glycans.