Allosteric sensitization of proapoptotic BAX

Nat Chem Biol. 2017 Sep;13(9):961-967. doi: 10.1038/nchembio.2433. Epub 2017 Jul 10.


BCL-2-associated X protein (BAX) is a critical apoptotic regulator that can be transformed from a cytosolic monomer into a lethal mitochondrial oligomer, yet drug strategies to modulate it are underdeveloped due to longstanding difficulties in conducting screens on this aggregation-prone protein. Here, we overcame prior challenges and performed an NMR-based fragment screen of full-length human BAX. We identified a compound that sensitizes BAX activation by binding to a pocket formed by the junction of the α3-α4 and α5-α6 hairpins. Biochemical and structural analyses revealed that the molecule sensitizes BAX by allosterically mobilizing the α1-α2 loop and BAX BH3 helix, two motifs implicated in the activation and oligomerization of BAX, respectively. By engaging a region of core hydrophobic interactions that otherwise preserve the BAX inactive state, the identified compound reveals fundamental mechanisms for conformational regulation of BAX and provides a new opportunity to reduce the apoptotic threshold for potential therapeutic benefit.

MeSH terms

  • Apoptosis
  • Dose-Response Relationship, Drug
  • Drug Delivery Systems
  • Humans
  • Magnetic Resonance Spectroscopy
  • Models, Molecular
  • Phenyl Ethers / chemistry
  • Phenyl Ethers / pharmacology*
  • Protein Binding
  • Proto-Oncogene Proteins c-bcl-2
  • bcl-2-Associated X Protein / chemistry*


  • Phenyl Ethers
  • Proto-Oncogene Proteins c-bcl-2
  • bcl-2-Associated X Protein
  • 4-phenoxyphenol

Associated data

  • PubChem-Substance/340075520
  • PubChem-Substance/340075521
  • PubChem-Substance/340075522
  • PubChem-Substance/340075523
  • PubChem-Substance/340075524
  • PubChem-Substance/340075525