Rab11 activity and PtdIns(3)P turnover removes recycling cargo from endosomes

Nat Chem Biol. 2018 Aug;14(8):801-810. doi: 10.1038/s41589-018-0086-4. Epub 2018 Jun 18.

Abstract

Directional transport of recycling cargo from early endosomes (EE) to the endocytic recycling compartment (ERC) relies on phosphatidylinositol 3-phosphate (PtdIns(3)P) hydrolysis and activation of the small GTPase Rab11. However, how these events are coordinated is yet unclear. By using a novel genetically-encoded FRET biosensor for Rab11, we report that generation of endosomal PtdIns(3)P by the clathrin-binding phosphoinositide 3-kinase class 2 alpha (PI3K-C2α) controls the activation of Rab11. Active Rab11, in turn, prompts the recruitment of the phosphatidylinositol 3-phosphatase myotubularin 1 (MTM1), eventually enabling the release of recycling cargo from the EE and its delivery toward the ERC. Our findings thus define that delivery of recycling cargo toward the ERC requires spatial and sequential coupling of Rab11 activity with PtdIns(3)P turnover.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • COS Cells
  • Chlorocebus aethiops
  • Endosomes / metabolism*
  • HEK293 Cells
  • Humans
  • Phosphoric Monoester Hydrolases / metabolism
  • rab GTP-Binding Proteins / metabolism*

Substances

  • Phosphoric Monoester Hydrolases
  • phosphatidylinositol-3-phosphatase
  • rab11 protein
  • rab GTP-Binding Proteins