Cell Reports (Mar 2023)

Interaction between PI3K and the VDAC2 channel tethers Ras-PI3K-positive endosomes to mitochondria and promotes endosome maturation

  • Aya O. Satoh,
  • Yoichiro Fujioka,
  • Sayaka Kashiwagi,
  • Aiko Yoshida,
  • Mari Fujioka,
  • Hitoshi Sasajima,
  • Asuka Nanbo,
  • Maho Amano,
  • Yusuke Ohba

Journal volume & issue
Vol. 42, no. 3
p. 112229

Abstract

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Summary: Intracellular organelles of mammalian cells communicate with one another during various cellular processes. The functions and molecular mechanisms of such interorganelle association remain largely unclear, however. We here identify voltage-dependent anion channel 2 (VDAC2), a mitochondrial outer membrane protein, as a binding partner of phosphoinositide 3-kinase (PI3K), a regulator of clathrin-independent endocytosis downstream of the small GTPase Ras. VDAC2 tethers endosomes positive for the Ras-PI3K complex to mitochondria in response to cell stimulation with epidermal growth factor and promotes clathrin-independent endocytosis, as well as endosome maturation at membrane association sites. With an optogenetics system to induce mitochondrion-endosome association, we find that, in addition to its structural role in such association, VDAC2 is functionally implicated in the promotion of endosome maturation. The mitochondrion-endosome association thus plays a role in the regulation of clathrin-independent endocytosis and endosome maturation.

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