Early/recycling endosomes-to-TGN transport involves two SNARE complexes and a Rab6 isoform

J Cell Biol. 2002 Feb 18;156(4):653-64. doi: 10.1083/jcb.200110081. Epub 2002 Feb 11.

Abstract

The molecular mechanisms underlying early/recycling endosomes-to-TGN transport are still not understood. We identified interactions between the TGN-localized putative t-SNAREs syntaxin 6, syntaxin 16, and Vti1a, and two early/recycling endosomal v-SNAREs, VAMP3/cellubrevin, and VAMP4. Using a novel permeabilized cell system, these proteins were functionally implicated in the post-Golgi retrograde transport step. The function of Rab6a' was also required, whereas its closely related isoform, Rab6a, has previously been implicated in Golgi-to-endoplasmic reticulum transport. Thus, our study shows that membrane exchange between the early endocytic and the biosynthetic/secretory pathways involves specific components of the Rab and SNARE machinery, and suggests that retrograde transport between early/recycling endosomes and the endoplasmic reticulum is critically dependent on the sequential action of two members of the Rab6 subfamily.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Biological Transport, Active
  • CHO Cells
  • Carrier Proteins / metabolism*
  • Cricetinae
  • Endosomes / metabolism*
  • HeLa Cells
  • Humans
  • Membrane Proteins / metabolism*
  • Protein Isoforms / metabolism
  • Qa-SNARE Proteins
  • Qb-SNARE Proteins
  • SNARE Proteins
  • Shiga Toxins / metabolism
  • Syntaxin 16
  • Vesicle-Associated Membrane Protein 3
  • Vesicular Transport Proteins*
  • rab GTP-Binding Proteins / metabolism*
  • trans-Golgi Network / metabolism*

Substances

  • Carrier Proteins
  • Membrane Proteins
  • Protein Isoforms
  • Qa-SNARE Proteins
  • Qb-SNARE Proteins
  • Rab6 protein
  • SNARE Proteins
  • Shiga Toxins
  • Syntaxin 16
  • VTI1A protein, human
  • Vesicle-Associated Membrane Protein 3
  • Vesicular Transport Proteins
  • rab GTP-Binding Proteins