Regulation of mitochondrial fission by GIPC-mediated Drp1 retrograde transport

Mol Biol Cell. 2022 Jan 1;33(1):ar4. doi: 10.1091/mbc.E21-06-0286. Epub 2021 Oct 27.

Abstract

Dynamin-related protein 1 (Drp1) is a key regulator of mitochondrial fission, a large cytoplasmic GTPase recruited to the mitochondrial surface via transmembrane adaptors to initiate scission. While Brownian motion likely accounts for the local interactions between Drp1 and the mitochondrial adaptors, how this essential enzyme is targeted from more distal regions like the cell periphery remains unknown. Based on proteomic interactome screening and cell-based studies, we report that GAIP/RGS19-interacting protein (GIPC) mediates the actin-based retrograde transport of Drp1 toward the perinuclear mitochondria to enhance fission. Drp1 interacts with GIPC through its atypical C-terminal PDZ-binding motif. Loss of this interaction abrogates Drp1 retrograde transport resulting in cytoplasmic mislocalization and reduced fission despite retaining normal intrinsic GTPase activity. Functionally, we demonstrate that GIPC potentiates the Drp1-driven proliferative and migratory capacity in cancer cells. Together, these findings establish a direct molecular link between altered GIPC expression and Drp1 function in cancer progression and metabolic disorders.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptor Proteins, Signal Transducing / metabolism*
  • Animals
  • COS Cells
  • Cell Line
  • Chlorocebus aethiops
  • Cytoplasm / metabolism
  • Cytosol / metabolism
  • Dynamins / genetics
  • Dynamins / metabolism*
  • GTP Phosphohydrolases / metabolism
  • Microtubule-Associated Proteins / metabolism
  • Microtubules / metabolism
  • Mitochondria / metabolism
  • Mitochondrial Dynamics / physiology*
  • Mitochondrial Proteins / metabolism
  • Protein Binding
  • Proteomics

Substances

  • Adaptor Proteins, Signal Transducing
  • Gipc1 protein, mouse
  • Microtubule-Associated Proteins
  • Mitochondrial Proteins
  • GTP Phosphohydrolases
  • Dnm1l protein, mouse
  • Dynamins