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  • The EMBO Journal (2007) 26, 825 - 834
  • doi:10.1038/sj.emboj.7601533

Published online: 18 January 2007

Bak and Bax are non-redundant during infection- and DNA damage-induced apoptosis

Oliver Kepp1,a, Krishnaraj Rajalingam1,ab, Sonja Kimmig1 and Thomas Rudel1

  1. Department of Molecular Biology, Max Planck Institute for Infection Biology, Research Group for Molecular Infection and Tumor Biology, Berlin, Germany

Correspondence to:

Thomas Rudel, Department of Molecular Biology, Max Planck Institute for Infection Biology, Research Group for Molecular Infection and Tumor Biology, Schumannstr. 21/22, Berlin 10117, Germany. Tel.: +49 30 28460 415; Fax: +49 30 28460 401; E-mail: rudel@mpiib-berlin.mpg.de

aThese authors contributed equally to the work

bPresent address: Institut fur Medizinische Strahlenkunde und Zellforschung, Bayerische Julius-Maximilians-Universitat, Versbacher-Str. 5, 97078 Wurzburg, Germany

Received 28 June 2006; Accepted 8 December 2006

Mitochondrial outer membrane permeabilization (MOMP) and release of mitochondrial intermembrane proteins like cytochrome c are critical steps in the control of apoptosis. Previous work has shown that MOMP depends on the functionally redundant multidomain proapoptotic proteins, Bak and Bax. Here we demonstrate that Bak and Bax are functionally non-redundant during Neisseria gonorrhoeae (Ngo)- and cisplatin-induced apoptosis. While the activation of Bak is caspase independent Bax activation needs Bak and active caspases. Silencing of either Bak or Bax resists both Ngo- and cisplatin- but not TNFalpha-induced apoptosis. Activation of Bak is required to release cytochrome c from the mitochondria; however, Bax is still required to activate effector caspases. Thus, both Bak and Bax are necessary to accomplish DNA damage and Ngo-induced apoptosis.

  • Keywords:

    • apoptosis,
    • Bak,
    • Bax,
    • DNA damage,
    • Neisseria,
    • mitochondria