Systematic Identification of MCU Modulators by Orthogonal Interspecies Chemical Screening

Mol Cell. 2017 Aug 17;67(4):711-723.e7. doi: 10.1016/j.molcel.2017.07.019.


The mitochondrial calcium uniporter complex is essential for calcium (Ca2+) uptake into mitochondria of all mammalian tissues, where it regulates bioenergetics, cell death, and Ca2+ signal transduction. Despite its involvement in several human diseases, we currently lack pharmacological agents for targeting uniporter activity. Here we introduce a high-throughput assay that selects for human MCU-specific small-molecule modulators in primary drug screens. Using isolated yeast mitochondria, reconstituted with human MCU, its essential regulator EMRE, and aequorin, and exploiting a D-lactate- and mannitol/sucrose-based bioenergetic shunt that greatly minimizes false-positive hits, we identify mitoxantrone out of more than 600 clinically approved drugs as a direct selective inhibitor of human MCU. We validate mitoxantrone in orthogonal mammalian cell-based assays, demonstrating that our screening approach is an effective and robust tool for MCU-specific drug discovery and, more generally, for the identification of compounds that target mitochondrial functions.

Keywords: MCU; bioenergetics; calcium; calcium signaling; drug discovery; drug screening; high-throughput screening; mitochondria; mitochondrial calcium uniporter.

MeSH terms

  • Aequorin / metabolism
  • Animals
  • Calcium / metabolism*
  • Calcium Channel Blockers / chemistry
  • Calcium Channel Blockers / pharmacology*
  • Calcium Channels / drug effects*
  • Calcium Channels / genetics
  • Calcium Channels / metabolism
  • Dose-Response Relationship, Drug
  • Drug Discovery / methods*
  • Energy Metabolism / drug effects
  • HEK293 Cells
  • HeLa Cells
  • High-Throughput Screening Assays*
  • Humans
  • Kinetics
  • Lactic Acid / metabolism
  • Mannitol / metabolism
  • Membrane Potentials
  • Mice, Transgenic
  • Mitochondria / drug effects*
  • Mitochondria / metabolism
  • Mitoxantrone / chemistry
  • Mitoxantrone / pharmacology*
  • Models, Molecular
  • Molecular Structure
  • Saccharomyces cerevisiae / drug effects*
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / metabolism
  • Structure-Activity Relationship
  • Sucrose / metabolism
  • Xenopus laevis


  • Calcium Channel Blockers
  • Calcium Channels
  • SMDT1 protein, human
  • mitochondrial calcium uniporter
  • Lactic Acid
  • Mannitol
  • Aequorin
  • Sucrose
  • Mitoxantrone
  • Calcium