Soussilane Pravina, D'Alessio Cecilia, Paccalet Thomas, Fitchette Anne-Catherine, Parodi Armando J, Williamson Richard, Plasson Carole, Faye Loïc, Gomord Véronique
CNRS, UMR 6037, IFRMP 23, Bâtiment Biologie Extension, Faculté des Sciences, Mont-Saint-Aignan, France.
Glycoconj J. 2009 Jul;26(5):597-607. doi: 10.1007/s10719-008-9201-1. Epub 2008 Oct 30.
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 alpha and beta subunits. Here we present the first characterization of a plant glucosidase II alpha subunit at the molecular level. Expression of the Arabidopsis alpha subunit restored N-glycan maturation capacity in Schizosaccharomyces pombe alpha- or alphabeta-deficient mutants, but with a lower efficiency in the last case. Inactivation of the alpha subunit in a temperature sensitive Arabidopsis mutant blocked N-glycan processing after a first trimming by glucosidase I and strongly affected seedling development.
葡糖苷酶II是早期N-聚糖加工酶之一，也是糖蛋白折叠质量控制中的主要参与者，它被描述为一种由α和β亚基组成的可溶性异二聚体。在此，我们首次在分子水平上对植物葡糖苷酶II的α亚基进行了表征。拟南芥α亚基的表达恢复了粟酒裂殖酵母α缺陷或αβ缺陷突变体中N-聚糖的成熟能力，但在后一种情况下效率较低。在温度敏感的拟南芥突变体中使α亚基失活，会在葡糖苷酶I首次修剪后阻断N-聚糖加工，并严重影响幼苗发育。
