Retention and degradation of N-glycoproteins in the rough endoplasmic reticulum

Biosci Rep. 1999 Oct;19(5):491-8. doi: 10.1023/a:1020228725997.

Abstract

Recent studies have shown that newly synthesized proteins and glycoproteins are submitted to a quality control mechanism in the rough endoplasmic reticulum (ER). In this report we present two models: One model will illustrate a transient retention in rough ER leading to a further degradation of glycoproteins in the cytosol, (soluble alkaline phosphatase expressed in Man-P-Dol deficient CHO cells lines). The second model will illustrate a strict retention of glycoproteins in rough ER without degradation nor recycling through the Golgi (E1, E2 glycoproteins of Hepatitis C virus in stably transfected UHCV-11.4 cells and in infected Hep G2 cells). In both cases, oligomannoside structures are markers of these phenomena, either as free soluble released oligomannosides in the case of degradation, or as N-linked oligomannosides for strict retention in rough ER.

MeSH terms

  • Alkaline Phosphatase / metabolism
  • Animals
  • CHO Cells
  • Chromatography, Affinity
  • Chromatography, High Pressure Liquid
  • Cricetinae
  • Endoplasmic Reticulum, Rough / chemistry
  • Endoplasmic Reticulum, Rough / metabolism*
  • Glycoproteins / chemistry
  • Glycoproteins / metabolism*
  • Golgi Apparatus / metabolism
  • Mutation
  • Solubility
  • Viral Envelope Proteins / metabolism

Substances

  • E1 protein, Hepatitis C virus
  • Glycoproteins
  • Viral Envelope Proteins
  • glycoprotein E2, Hepatitis C virus
  • Alkaline Phosphatase