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Receptor mediated endocytosis 8 is a novel PI(3)P binding protein regulated by myotubularin-related 2

Besa Xhabija1, Gregory S Taylor, Akemi Fujibayashi

  • 1Department of Chemistry and Biochemistry, University of Windsor, Windsor, Ontario, Canada.

FEBS Letters
|April 23, 2011
PubMed

Insights

Myotubularin related protein 2 (MTMR2) regulates endosomal protein RME-8 localization. MTMR2 activity and PI(3)P binding control RME-8

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Biochemistry

Background:

  • Myotubularin related protein 2 (MTMR2) is a phosphoinositide lipid phosphatase.
  • Proteins regulated by MTMR2 are not well understood.

Purpose of the Study:

  • Identify novel PI(3)P binding proteins regulated by MTMR2.
  • Characterize the role of MTMR2 in RME-8 localization.

Main Methods:

  • Phosphoinositide affinity chromatography coupled to mass spectrometry.
  • Co-localization studies using DsRed-FYVE and EGFR markers.
  • In vitro binding assays and in vivo protein depletion experiments.

Main Results:

  • Receptor mediated endocytosis 8 (RME-8) identified as a PI(3)P binding protein.
  • RME-8 N-terminal region is crucial for PI(3)P and PI(3,5)P2 binding.
  • MTMR2 activity and PI(3)P levels affect RME-8 endosomal localization.

Conclusions:

  • MTMR2 regulates RME-8 localization via PI(3)P binding.
  • RME-8 localization is spatially mediated by PI(3)P and temporally regulated by MTMR2.
  • This study elucidates a novel regulatory mechanism in endosomal trafficking.

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