PMID: 20837471

 

    Legend: Gene, Sites

Title : O-glycosylation modulates proprotein convertase activation of angiopoietin-like protein 3 : possible role of polypeptide GalNAc-transferase-2 in regulation of concentrations of plasma lipids

Abstract :
  1. The angiopoietin-like protein 3 ( ANGPTL3 ) is an important inhibitor of the endothelial and lipoprotein lipases and a promising drug target
  2. ANGPTL3 undergoes proprotein convertase processing (RAPR(224)↓TT) for activation, and the processing site contains two potential GalNAc O-glycosylation sites immediately C-terminal (TT(226))
  3. We developed an in vivo model system in CHO ldlD cells that was used to show that O-glycosylation in the processing site blocked processing of ANGPTL3
  4. Genome-wide SNP association studies have identified the polypeptide GalNAc-transferase gene, GALNT2 , as a candidate gene for low HDL and high triglyceride blood levels
  5. We hypothesized that the GalNAc-T2 transferase performed critical O-glycosylation of proteins involved in lipid metabolism
  6. Screening of a panel of proteins known to affect lipid metabolism for potential sites glycosylated by GalNAc-T2 led to identification of Thr(226) adjacent to the proprotein convertase processing site in ANGPTL3
  7. We demonstrated that GalNAc-T2 glycosylation of Thr(226) in a peptide with the RAPR(224)↓TT processing site blocks in vitro furin cleavage
  8. The study demonstrates that ANGPTL3 activation is modulated by O-glycosylation and that this step is probably controlled by GalNAc-T2
Output (sent_index, trigger, protein, sugar, site):
  • 2. contains, , -, two potential GalNAc O-glycosylation sites immediately C-terminal (TT(226)), site
  • 3. O-glycosylation, , -, -, site
  • 5. O-glycosylation, , proteins, -, -
  • 6. Thr, , -, -, site
  • 6. glycosylated, , -, -, sites
  • 7. Thr, , -, GalNAc-T2 glycosylation, Thr(226)
  • 7. glycosylation, , -, -, Thr(226)
  • 7. glycosylation, , -, a peptide, peptide
Output(Part-Of) (sent_index, protein, site):
  • 6. ANGPTL3, Thr(226)
  • 7. -, site
*Output_Site_Fusion* (sent_index, protein, sugar, site):
  • 7. ANGPTL3, -, Thr(226)
  • 7. ANGPTL3, GalNAc-T2 glycosylation, Thr(226)

 

 

Protein NCBI ID SENTENCE INDEX
angiopoietin-like protein 3 100754950 0,1
ANGPTL3 100754950 1,2,3,6,8
GALNT2 100767525 4