Regulation of caveolar endocytosis by syntaxin 6-dependent delivery of membrane components to the cell surface

Amit Choudhury, David L. Marks, Kirsty M. Proctor, Gwyn W. Gould, Richard E. Pagano

Research output: Contribution to journalArticle

68 Citations (Scopus)

Abstract

Caveolar endocytosis has an important function in the cellular uptake of some bacterial toxins, viruses and circulating proteins. However, the molecular machinery involved in regulating caveolar uptake is poorly defined. Here, we demonstrate that caveolar endocytosis is regulated by syntaxin 6, a target membrane soluble N-ethylmaleimide attachment protein receptor (t-SNARE) involved in membrane fusion events along the secretory pathway. When syntaxin 6 function was inhibited, internalization through caveolae was dramatically reduced, whereas other endocytic mechanisms were unaffected. Syntaxin 6 inhibition also reduced the presence of caveolin-1 and caveolae at the plasma membrane. In addition, syntaxin 6 inhibition decreased the delivery of GM1 ganglioside (GM1) and glycosylphosphatidylinositol (GPI)-GFP (but not vesicular stomatitis virus-glycoprotein G; VSV-G) protein from the Golgi complex to the plasma membrane. Addition of GM1 to syntaxin 6-inhibited cells resulted in the reappearance of caveolin-1 and caveolae at the plasma membrane, and restored caveolar uptake. These results suggest that syntaxin 6 regulates the delivery of microdomain-associated lipids and proteins to the cell surface, which are required for caveolar endocytosis.

Original languageEnglish
Pages (from-to)317-328
Number of pages12
JournalNature Cell Biology
Volume8
Issue number4
Early online date26 Mar 2006
DOIs
Publication statusPublished - 30 Apr 2006

Keywords

  • caveolar endocytosis
  • uptake
  • protein receptor
  • syntaxin 6 inhibition

Cite this