PIGB

Alpha-1,2-mannosyltransferase that catalyzes the transfer of the third mannose, via an alpha-1,2 bond, from a dolichol-phosphate-mannose (Dol-P-Man) to a 2-acyl-6-[alpha-D-mannosyl-(1->6)-2-phosphoethanolamine-alpha-D-mannosyl-(1->4)-alpha-D-glucosaminyl]-1-(1-radyl,2-acyl-sn-glycero-3-phospho)-1D-myo-inositol intermediate to generate a 2-acyl-6-[alpha-D-mannosyl-(1->2)-alpha-D-mannosyl-(1->6)-2-phosphoethanolamine-alpha-D-mannosyl-(1->4)-alpha-D-glucosaminyl]-1-(1-radyl,2-acyl-sn-glycero-3-phospho)-1D-myo-inositol (also termed H6) and participates in the nineth step of the glycosylphosphatidylinositol-anchor biosynthesis (Probable). May also add the third mannose to a 2-acyl-6-[alpha-D-mannosyl-(1->6)-alpha-D-mannosyl-(1->4)-alpha-D-glucosaminyl]-1-(1-radyl,2-acyl-sn-glycero-3-phospho)-1D-myo-inositol (also termed H3) intermediate generating a 2-acyl-6-(alpha-D-mannosyl-(1->2)-alpha-D-mannosyl-(1->6)-alpha-D-mannosyl-(1->4)-alpha-D-glucosaminyl)-1-(1-radyl,2-acyl-sn-glycero-3-phospho)-1D-myo-inositol (also termed H4) (Probable)..

Function from UniProtKB (Q92521), read 2026-09-23. CC BY 4.0.