Asparagine Linked Glycosylation Protein 11 (ALG11)

ALG11 is a mannosyltransferase that uses GDP-mannose to sequentially add the fourth and fifth mannose residues to growing dolichol-linked oligosaccharide side chains at the outer leaflet of the endoplasmic reticulum (ER). Upon completion, the lipid-linked polyoligosaccharides are translocated to the ER lumen for subsequent transfer to substrate asparagine residues of newly synthesized glycoproteins. ALG11 contains 2 Rossmann-like type B domains, which are separated by a catalytic flexible hinge region, and a conserved C-terminal nucleotide sugar-binding region. ALG11 also has 2 predicted transmembrane domains and 2 putative N-glycosylation sites. Immunofluorescence analysis of human fibroblasts revealed colocalization of ALG11 with an ER marker, calnexin (CANX).