Reaction: ALG9 transfers Man to N-glycan precursor (GlcNAc)2 (Man)8 (PP-Dol)1
- in pathway: Biosynthesis of the N-glycan precursor (dolichol lipid-linked oligosaccharide, LLO) and transfer to a nascent protein
The last mannose is added to the N-glycan precursor. This reaction occurs in the ER lumen, uses Dolichyl phosphate D-mannose as the mannose donor, and is catalyzed by ALG9. Defects in ALG9 are the cause of congenital disorder of glycosylation type 1L (CDG1L) (Frank CG et al, 2004; Weinstein M et al, 2005). For many years ALG9 was thought to be involved in bipolar affective disorder (Baysal BE et al, 2002), but this hypothesis has been proven wrong (Baysal BE et al, 2006).
Reaction - small molecule participants:
(GlcNAc)2 (Man)9 (PP-Dol)1 [integral component of lumenal side of endoplasmic reticulum membrane]
DOLP [integral component of lumenal side of endoplasmic reticulum membrane]
DOLP-Man [integral component of lumenal side of endoplasmic reticulum membrane]
(GlcNAc)2 (Man)8 (PP-Dol)1 [integral component of lumenal side of endoplasmic reticulum membrane]
Reactome.org reaction link: R-HSA-446216
======
Reaction input - small molecules:
dolichyl D-mannosyl phosphate(1-)
alpha-Man-(1->2)-alpha-Man-(1->2)-alpha-Man-(1->3)-[alpha-Man-(1->6)-[alpha-Man-(1->2)-alpha-Man-(1->3)]-alpha-Man-(1->6)]-beta-Man-(1->4)-beta-GlcNAc-(1->4)-alpha-GlcNAc(PP-Dol)
Reaction output - small molecules:
alpha-Man-(1->2)-alpha-Man-(1->2)-alpha-Man-(1->3)-[alpha-Man-(1->2)-alpha-Man-(1->3)-[alpha-Man-(1->2)-alpha-Man-(1->6)]-alpha-Man-(1->6)]-beta-Man-(1->4)-beta-GlcNAc-(1->4)-alpha-GlcNAc(PP-Dol)
dolichyl phosphate(2-)
Reactome.org link: R-HSA-446216