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Updated: Nov 2, 2025

Visualization and Quantification of Endogenous Intra-Organelle Protein Interactions at ER-Mitochondria Contact Sites by Proximity Ligation Assays
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Visualization and Quantification of Endogenous Intra-Organelle Protein Interactions at ER-Mitochondria Contact Sites by Proximity Ligation Assays

Published on: October 20, 2023

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VPS13D interacts with VCP/p97 and negatively regulates endoplasmic reticulum-mitochondria interactions

Yuanjiao Du1, Jingru Wang1, Juan Xiong2

  • 1Department of Biochemistry and Molecular Biology, School of Basic Medicine.

Molecular Biology of the Cell
|June 16, 2021
PubMed

Insights

Vacuolar protein sorting-associated protein 13D (VPS13D) negatively regulates membrane contact sites between the endoplasmic reticulum and mitochondria. Loss of VPS13D causes excessive tethering, impacting mitochondrial function and linked to neurodegenerative diseases.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Neuroscience

Background:

  • Membrane contact sites (MCSs) between the endoplasmic reticulum (ER) and mitochondria are crucial for cellular processes.
  • Dysregulation of ER-mitochondria MCSs is implicated in neurodegenerative diseases.
  • Mechanisms controlling ER-mitochondria interactions remain largely unknown.

Purpose of the Study:

  • To investigate the role of vacuolar protein sorting-associated protein 13D (VPS13D) in regulating ER-mitochondria MCSs.
  • To elucidate the molecular mechanisms underlying VPS13D's function at these contacts.

Main Methods:

  • CRISPR-based screening to identify regulators of ER-mitochondria contacts.
  • Yeast-two-hybrid assays to identify interacting proteins.
  • Confocal microscopy to assess mitochondrial morphology and distribution.
  • Western blotting to evaluate protein levels and interactions.

Main Results:

  • VPS13D negatively regulates ER-mitochondria MCSs, with VPS13D suppression leading to excessive tethering.
  • VPS13D interacts with valosin-containing protein (VCP/p97) and influences VAPB levels at ER-mitochondria contacts.
  • VPS13D is essential for the stability of VCP/p97.
  • Loss of VPS13D causes severe defects in mitochondrial morphology, distribution, and DNA synthesis.

Conclusions:

  • VPS13D acts as a negative regulator of ER-mitochondria MCSs, partly via its interaction with VCP/p97.
  • VPS13D's function is critical for maintaining mitochondrial homeostasis.
  • Understanding VPS13D's role provides insights into potential therapeutic targets for neurodegenerative diseases associated with MCS dysfunction.

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