EGF stimulates annexin 1-dependent inward vesiculation in a multivesicular endosome subpopulation

EMBO J. 2006 Jan 11;25(1):1-12. doi: 10.1038/sj.emboj.7600759. Epub 2005 Jul 28.

Abstract

Here we show that EGF and EGF receptor (EGFR) are trafficked through a subpopulation of multivesicular endosomes/bodies (MVBs) that are distinct from morphologically identical vacuoles that label for the late endosomal marker lyso-bisphosphatidic acid (LBPA). EGF stimulation increases both MVB biogenesis and inward vesiculation within EGFR-containing MVBs. Deletion of annexin 1, a substrate of EGFR tyrosine kinase, abolishes the effect of EGF stimulation on inward vesiculation. This phenotype is reversible by transfection with wild-type but not Y21F phosphorylation mutant annexin 1. Deletion of annexin 1 has no effect on EGF-stimulated MVB biogenesis, suggesting that MVB biogenesis and inward vesiculation within MVB are mediated by separate mechanisms. Loss or depletion of annexin 1 has no effect on EGF degradation and causes only a small delay in EGFR degradation, indicating that annexin 1 operates downstream of Hrs- and ESCRT-mediated sorting and is required solely for EGF-stimulated inward vesiculation. Annexin 1 accumulates on internal vesicles of MVB after EGF-stimulated inward vesiculation, suggesting that it may be required for a late stage in inward vesiculation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Annexin A1 / analysis
  • Annexin A1 / genetics
  • Annexin A1 / metabolism*
  • Cells, Cultured
  • Endosomes / drug effects
  • Endosomes / metabolism*
  • Endosomes / ultrastructure
  • Epidermal Growth Factor / metabolism*
  • Epidermal Growth Factor / pharmacology*
  • ErbB Receptors / analysis
  • ErbB Receptors / metabolism*
  • Gene Deletion
  • Humans
  • Lysophospholipids / analysis
  • Lysophospholipids / metabolism
  • Mice
  • Monoglycerides / analysis
  • Monoglycerides / metabolism
  • Phosphorylation
  • Protein Transport
  • Transport Vesicles / metabolism*
  • Transport Vesicles / ultrastructure
  • Vacuoles / chemistry

Substances

  • Annexin A1
  • Lysophospholipids
  • Monoglycerides
  • bis(monoacylglyceryl)phosphate
  • Epidermal Growth Factor
  • ErbB Receptors