Mitochondrial Sirtuin Network Reveals Dynamic SIRT3-Dependent Deacetylation in Response to Membrane Depolarization

Cell. 2016 Nov 3;167(4):985-1000.e21. doi: 10.1016/j.cell.2016.10.016. Epub 2016 Oct 27.


Mitochondrial sirtuins, SIRT3-5, are NAD+-dependent deacylases and ADP-ribosyltransferases that are critical for stress responses. However, a comprehensive understanding of sirtuin targets, regulation of sirtuin activity, and the relationships between sirtuins remains a key challenge in mitochondrial physiology. Here, we employ systematic interaction proteomics to elucidate the mitochondrial sirtuin protein interaction landscape. This work reveals sirtuin interactions with numerous functional modules within mitochondria, identifies candidate sirtuin substrates, and uncovers a fundamental role for sequestration of SIRT3 by ATP synthase in mitochondrial homeostasis. In healthy mitochondria, a pool of SIRT3 binds ATP synthase, but upon matrix pH reduction with concomitant loss of mitochondrial membrane potential, SIRT3 dissociates. This release correlates with rapid deacetylation of matrix proteins, and SIRT3 is required for recovery of membrane potential. In vitro reconstitution experiments, as well as analysis of CRISPR/Cas9-engineered cells, indicate that pH-dependent SIRT3 release requires H135 in the ATP5O subunit of ATP synthase. Our SIRT3-5 interaction network provides a framework for discovering novel biological functions regulated by mitochondrial sirtuins.

Keywords: ATP synthase; Acetylation; Deacetylation; Energy homeostasis; Interactome; Membrane potential; Mitochondria; Protein-protein interaction; Sirtuin; pH.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetylation
  • Adenosine Triphosphatases / metabolism
  • Animals
  • Carrier Proteins / metabolism
  • HeLa Cells
  • Humans
  • Immunoprecipitation
  • Membrane Proteins / metabolism
  • Mice
  • Mitochondria / metabolism*
  • Mitochondrial Proteins / metabolism
  • Mitochondrial Proton-Translocating ATPases
  • Protein Interaction Maps*
  • Sirtuin 3 / metabolism*
  • Sirtuins / classification
  • Sirtuins / metabolism


  • Carrier Proteins
  • Membrane Proteins
  • Mitochondrial Proteins
  • SIRT3 protein, human
  • Sirtuin 3
  • Sirtuins
  • Adenosine Triphosphatases
  • Mitochondrial Proton-Translocating ATPases
  • oligomycin sensitivity-conferring protein