Essential role of voltage-dependent anion channel in various forms of apoptosis in mammalian cells.
Through direct interaction with the voltage-dependent anion channel (VDAC), proapoptotic members of the Bcl-2 family such as Bax and Bak induce apoptogenic cytochrome c release in isolated mitochondria, whereas BH3-only proteins such as Bid and Bik do not directly target the VDAC to induce cytochrome c release. To investigate the biological significance of the VDAC for apoptosis in mammalian cells, we produced two kinds of anti-VDAC antibodies that inhibited VDAC activity. In isolated mitochondria, these antibodies prevented Bax-induced cytochrome c release and loss of the mitochondrial membrane potential (Deltapsi), but not Bid-induced cytochrome c release. When microinjected into cells, these anti-VDAC antibodies, but not control antibodies, also prevented Bax-induced cytochrome c release and apoptosis, whereas the antibodies did not prevent Bid-induced apoptosis, indicating that the VDAC is essential for Bax-induced, but not Bid-induced, apoptogenic mitochondrial changes and apoptotic cell death. In addition, microinjection of these anti-VDAC antibodies significantly inhibited etoposide-, paclitaxel-, and staurosporine-induced apoptosis. Furthermore, we used these antibodies to show that Bax- and Bak-induced lysis of red blood cells was also mediated by the VDAC on plasma membrane. Taken together, our data provide evidence that the VDAC plays an essential role in apoptogenic cytochrome c release and apoptosis in mammalian cells.
Osaka University Graduate School of Medicine, Biomedical Research Center, Department of Medical Genetics, Osaka 565-0871, Japan.
S
S
Shimizu
Y
Y
Matsuoka
Y
Y
Shinohara
Y
Y
Yoneda
Y
Y
Tsujimoto
D000595:Amino Acid Sequence; D000818:Animals; D000906:Antibodies / Q000494:pharmacology; D000911:Antibodies, Monoclonal / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology*; D051017:Apoptosis Regulatory Proteins; D051023:BH3 Interacting Domain Death Agonist Protein; D002352:Carrier Proteins / Q000378:metabolism; D003574:Cytochrome c Group / Q000378:metabolism; D004912:Erythrocytes / Q000502:physiology; D005047:Etoposide / Q000494:pharmacology; D006367:HeLa Cells; D006801:Humans; D007473:Ion Channels / Q000502:physiology*; D008322:Mammals; D008565:Membrane Proteins / Q000378:metabolism; D008928:Mitochondria / Q000502:physiology*; D008930:Mitochondria, Liver / Q000502:physiology*; D024101:Mitochondrial Proteins; D008969:Molecular Sequence Data; D017239:Paclitaxel / Q000494:pharmacology; D018272:Porins / Q000737:chemistry / Q000502:physiology*; D011487:Protein Conformation; D011506:Proteins / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D011994:Recombinant Proteins / Q000378:metabolism; D019311:Staurosporine / Q000494:pharmacology; D014162:Transfection; D050994:Voltage-Dependent Anion Channels; D050998:bcl-2 Homologous Antagonist-Killer Protein; D051028:bcl-2-Associated X Protein
D000906:Antibodies; D000911:Antibodies, Monoclonal; D051017:Apoptosis Regulatory Proteins; C494772:BAK1 protein, human; C494826:BAX protein, human; D051023:BH3 Interacting Domain Death Agonist Protein; C494814:BID protein, human; C096820:BIK protein, human; C494774:Bak1 protein, rat; C494828:Bax protein, rat; C494816:Bid protein, rat; D002352:Carrier Proteins; D003574:Cytochrome c Group; D007473:Ion Channels; D008565:Membrane Proteins; D024101:Mitochondrial Proteins; D018272:Porins; D011506:Proteins; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D011994:Recombinant Proteins; D050994:Voltage-Dependent Anion Channels; D050998:bcl-2 Homologous Antagonist-Killer Protein; D051028:bcl-2-Associated X Protein; D005047:Etoposide; D019311:Staurosporine; D017239:Paclitaxel