EC Number   |
Natural Substrates |
|---|
    2.4.1.258 | dolichyl beta-D-mannosyl phosphate + D-Man-alpha-(1->2)-D-Man-alpha-(1->2)-D-Man-alpha-(1->3)-[D-Man-alpha-(1->6)]-D-Man-beta-(1->4)-D-GlcNAc-beta-(1->4)-D-GlcNAc-diphosphodolichol |
regulatory role for the Alg3p-dependent alpha1,3-linked Man in subsequent oligosaccharide-lipid and glycoprotein glycan maturation. The presence of this Man appears to provide structural information potentiating the downstream action of the endoplasmic reticulum glucosyltransferases Alg6p, Alg8p and Alg10p, glucosidases Gls1p and Gls2p, and the Golgi Och1p outerchain alpha1,6-Man branch-initiating mannosyltransferase |
| 2.4.1.258 | dolichyl beta-D-mannosyl phosphate + D-Man-alpha-(1->2)-D-Man-alpha-(1->2)-D-Man-alpha-(1->3)-[D-Man-alpha-(1->6)]-D-Man-beta-(1->4)-D-GlcNAc-beta-(1->4)-D-GlcNAc-diphosphodolichol |
the core oligosaccharide Glc3Man9GlcNAc2 is assembled by a series of membrane-bound glycosyltransferases as the lipid carrier dolichylpyrophosphate-linked glycan in the endoplasmic reticulum (ER). The first step of this assembly pathway on the ER luminal side is mediated by ALG3. AtALG3 is a critical factor for mature N-glycosylation of proteins, but not essential for cell viability and growth in Arabidopsis |
| 2.4.1.258 | dolichyl beta-D-mannosyl phosphate + D-Man-alpha-(1->2)-D-Man-alpha-(1->2)-D-Man-alpha-(1->3)-[D-Man-alpha-(1->6)]-D-Man-beta-(1->4)-D-GlcNAc-beta-(1->4)-D-GlcNAc-diphosphodolichol |
the formation of N-glycosidic linkages of glycoproteins involves the ordered assembly of the common Glc3Man9GlcNAc2 core-oligosaccharide on the lipid carrier dolichyl diphosphate. Early mannosylation steps occur on the cytoplasmic side of the endoplasmic reticulum with GDP-Man as donor, the final reactions from Man5GlcNAc2-PP-Dol to Man9Glc-NAc2-PP-Dol on the lumenal side use dolichyl beta-D-mannosyl phosphate. Alg3p is not required for elongation of D-Man-alpha-(1->2)-D-Man-alpha-(1->2)-D-Man-alpha-(1->3)-[D-Man-alpha-(1->3)-D-Man-alpha-(1->6)]-D-Man-beta-(1->4)-D-GlcNAc-beta-(1->4)-D-GlcNAc-diphosphodolichol |
| 2.4.1.258 | more |
regulatory role for the Alg3p-dependent alpha-1,3-linked Man in subsequent oligosaccharide-lipid and glycoprotein glycan maturation, it provides structural information that potentiates the Alg6p, Alg8p and Alg10p ER glucosyltransferases and Gls1p and Gls2p trimming glucosidases |
| 2.4.1.258 | more |
involved in oligosaccharide-lipid synthesis |
