Caveolin-1 is not essential for biosynthetic apical membrane transport

Mol Cell Biol. 2005 Nov;25(22):10087-96. doi: 10.1128/MCB.25.22.10087-10096.2005.

Abstract

Caveolin-1 has been implicated in apical transport of glycosylphosphatidylinositol (GPI)-anchored proteins and influenza virus hemagglutinin (HA). Here we have studied the role of caveolin-1 in apical membrane transport by generating caveolin-1-deficient Madin-Darby canine kidney (MDCK) cells using retrovirus-mediated RNA interference. The caveolin-1 knockdown (cav1-KD) MDCK cells were devoid of caveolae. In addition, caveolin-2 was retained in the Golgi apparatus in cav1-KD MDCK cells. However, we found no significant alterations in the apical transport kinetics of GPI-anchored proteins or HA upon depletion of caveolin-1. Similar results were obtained using embryonic fibroblasts from caveolin-1-knockout mice. Thus, we conclude that caveolin-1 does not play a major role in lipid raft-mediated biosynthetic membrane trafficking.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenoviridae / metabolism
  • Animals
  • Biological Transport
  • Biotin / chemistry
  • Biotinylation
  • Caveolin 1 / genetics
  • Caveolin 1 / metabolism
  • Caveolin 1 / physiology*
  • Caveolin 2 / genetics
  • Caveolin 2 / metabolism
  • Cell Line
  • Cell Membrane / metabolism
  • Cholesterol / metabolism
  • Dogs
  • Dose-Response Relationship, Drug
  • Fibroblasts / metabolism
  • Glycosylphosphatidylinositols / metabolism
  • Golgi Apparatus / metabolism
  • Hemagglutinin Glycoproteins, Influenza Virus / metabolism
  • Immunohistochemistry
  • Kinetics
  • Membrane Microdomains
  • Mice
  • Mice, Knockout
  • Microscopy, Electron
  • Microscopy, Fluorescence
  • RNA Interference
  • Retroviridae / genetics
  • Retroviridae / metabolism
  • Temperature
  • Time Factors
  • Transgenes

Substances

  • Caveolin 1
  • Caveolin 2
  • Glycosylphosphatidylinositols
  • Hemagglutinin Glycoproteins, Influenza Virus
  • Biotin
  • Cholesterol