• Media type: E-Article
  • Title: Impact of glycosylation and detergent-resistant membranes on the function of intestinal sucrase-isomaltase
  • Contributor: Wetzel, Gabi; Heine, Martin; Rohwedder, Arndt; Naim, Hassan Y.
  • Published: Walter de Gruyter GmbH, 2009
  • Published in: bchm, 390 (2009) 7, Seite 545-549
  • Language: English
  • DOI: 10.1515/bc.2009.077
  • ISSN: 1431-6730; 1437-4315
  • Origination:
  • Footnote:
  • Description: Abstract Sucrase-isomaltase (SI) is a highly N- and O-glycosylated intestinal brush border membrane protein. SI is sorted with high fidelity to the apical membrane via O-linked glycans that mediate its association with lipid rafts or detergent-resistant membranes (DRMs). Here, we show that N- and O-glycosylation and DRMs are implicated in the regulation of the function of SI in intestinal Caco-2 cells. The activities of sucrase (SUC) and isomaltase (IM) increase substantially in DRMs when N- and O-glycosylation patterns are intact. Disruption of DRMs by solubilization with Triton X-100 at 37°C substantially reduces the activities of SUC and IM. Furthermore, modulation of O-glycosylation by benzyl-2-acetamido-2-deoxy-α-d-galactopyranoside and N-glycosylation by deoxymannojirimycin is linked to a decreased capacity of SI to associate with DRMs, with a subsequent reduction of the enzymatic activities of SUC and IM. This is the first report that reveals a direct role of N- and O-glycans in association with DRMs in regulating the function of a membrane glycoprotein.