Cholesterol-independent targeting of Golgi membrane proteins in insect cells

Mol Biol Cell. 1997 Nov;8(11):2111-8. doi: 10.1091/mbc.8.11.2111.

Abstract

Distinct lipid compositions of intracellular organelles could provide a physical basis for targeting of membrane proteins, particularly where transmembrane domains have been shown to play a role. We tested the possibility that cholesterol is required for targeting of membrane proteins to the Golgi complex. We used insect cells for our studies because they are cholesterol auxotrophs and can be depleted of cholesterol by growth in delipidated serum. We found that two well-characterized mammalian Golgi proteins were targeted to the Golgi region of Aedes albopictus cells, both in the presence and absence of cellular cholesterol. Our results imply that a cholesterol gradient through the secretory pathway is not required for membrane protein targeting to the Golgi complex, at least in insect cells.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Aedes / chemistry*
  • Animals
  • Biological Transport
  • Cattle
  • Cell Line
  • Cholesterol / physiology*
  • Golgi Apparatus / chemistry*
  • Mannosidases / analysis
  • Mannosidases / metabolism
  • Membrane Proteins / analysis*
  • Membrane Proteins / metabolism
  • Mice
  • N-Acetyllactosamine Synthase / analysis
  • N-Acetyllactosamine Synthase / metabolism
  • Recombinant Fusion Proteins
  • alpha-Mannosidase

Substances

  • Membrane Proteins
  • Recombinant Fusion Proteins
  • Cholesterol
  • N-Acetyllactosamine Synthase
  • Mannosidases
  • alpha-Mannosidase