N-glycan trimming by glucosidase II is essential for Arabidopsis development

PRAVINA SOUSSILANE; CECILIA D´ALESSIO; THOMAS PACCALET; ANNE-CATHERINE FITCHETTE; ARMANDO J. PARODI; RICHARD WILLIAMSON; CAROLE PLASSON; LOIC FAYE; VERONIQUE GOMORD

GLYCOCONJUGATE JOURNAL

SPRINGER

Año: 2009 vol. 26 p. 597 - 607

0282-0080

Glucosidase II, one of the early N-glycan processing enzymes and a major player in the glycoprotein folding quality control, has been described as a soluble heterodimer composed of á and â subunits. Here we present the first characterization of a plant glucosidase II á subunit at the molecular level. Expression of the Arabidopsis á subunit restored N-glycan maturation capacity in Schizosaccharomyces pombe á− or áâ−deficient mutants, but with a lower efficiency in the last case. Inactivation of the á subunit in a temperature sensitive Arabidopsis mutant blocked N-glycan processing after a first trimming by glucosidase I and strongly affected seedling development.