A chemical inhibitor of Apaf-1 exerts mitochondrioprotective functions and interferes with the intra-S-phase DNA damage checkpoint Academic Article uri icon


MeSH Major

  • Apoptotic Protease-Activating Factor 1
  • Azepines
  • DNA Damage
  • Mitochondria
  • Peptoids
  • S Phase


  • QM31 represents a new class of cytoprotective agents that inhibit the formation of the apoptosome, the caspase activation complex composed by Apaf-1, cytochrome c, dATP and caspase-9. Here, we analyzed the cellular effects of QM31, as compared to the prototypic caspase inhibitor Z-VAD-fmk. QM31 was as efficient as Z-VAD-fmk in suppressing caspase-3 activation, and conferred a similar cytoprotective effect. In contrast to Z-VAD-fmk, QM31 inhibited the release of cytochrome c from mitochondria, an unforeseen property that may contribute to its pronounced cytoprotective activity. Moreover, QM31 suppressed the Apaf-1-dependent intra-S-phase DNA damage checkpoint. These results suggest that QM31 can interfere with the two known functions of Apaf-1, namely apoptosome assembly/activation and intra-S-phase cell cycle arrest. Moreover, QM31 can inhibit mitochondrial outer membrane permeabilization, an effect that is independent from its action on Apaf-1.

publication date

  • February 2009



  • Academic Article



  • eng

Digital Object Identifier (DOI)

  • 10.1007/s10495-008-0310-x

PubMed ID

  • 19152031

Additional Document Info

start page

  • 182

end page

  • 90


  • 14


  • 2