Bax-dependent regulation of Bak by voltage-dependent anion channel 2

被引:81
作者
Chandra, D
Choy, G
Daniel, PT
Tang, DG
机构
[1] Univ Texas, MD Anderson Canc Ctr, Dept Carcinogenesis, Div Sci Pk Res, Smithville, TX 78957 USA
[2] Humboldt Univ, Univ Med Ctr Charite, Dept Hematol Oncol & Tumor Immunol, D-13125 Berlin, Germany
关键词
D O I
10.1074/jbc.M501391200
中图分类号
Q5 [生物化学]; Q7 [分子生物学];
学科分类号
071010 ; 081704 ;
摘要
Many studies have demonstrated a critical role of Bax in mediating apoptosis, but the role of Bak in regulating cancer cell apoptotic sensitivities in the presence or absence of Bax remains incompletely understood. Using isogenic cells with defined genetic deficiencies, here we show that in response to intrinsic, extrinsic, and endoplasmic reticulum stress stimuli, HCT116 cells show clear-cut apoptotic sensitivities in the order of Bax(+)/Bak(+) > Bax(+)/Bak(-) >> Bax(-)/Bak(+) >> Bax(-)/Bak(-). Small interference RNA-mediated knockdown of Bak in Bax-deficient cells renders HCT116 cells completely resistant to apoptosis induction. Surprisingly, however, Bak knockdown in Bax-expressing cells only slightly affects the apoptotic sensitivities. Bak, like Bax, undergoes the N terminus exposure upon apoptotic stimulation in both Bax-expressing and Bax-deficient cells. Gel filtration, chemical cross-linking, and co-immunoprecipitation experiments reveal that different from Bax, which normally exists as monomers in unstimulated cells and is oligomerized by apoptotic stimulation, most Bak in unstimulated HCT116 cells exists in two distinct protein complexes, one of which contains voltage-dependent anion channel (VDAC) 2. During apoptosis, Bak and Bax form both homo- and hetero-oligomeric complexes that still retain some VDAC-2. However, the oligomeric VDAC-2 complexes are diminished, and Bak does not interact with VDAC-2 in Bax-deficient HCT116 cells. These results highlight VDAC-2 as a critical inhibitor of Bak-mediated apoptotic responses.
引用
收藏
页码:19051 / 19061
页数:11
相关论文
共 55 条
[1]   Mitochondrial release of AIF and EndoG requires caspase activation downstream of Bax/Bak-mediated permeabilization [J].
Arnoult, D ;
Gaume, B ;
Karbowski, M ;
Sharpe, JC ;
Cecconi, F ;
Youle, RJ .
EMBO JOURNAL, 2003, 22 (17) :4385-4399
[2]   CD95 ligand induces motility and invasiveness of apoptosis-resistant tumor cells [J].
Barnhart, BC ;
Legembre, P ;
Pietras, E ;
Bubici, C ;
Franzoso, G ;
Peter, ME .
EMBO JOURNAL, 2004, 23 (15) :3175-3185
[3]   Bax-type apoptotic proteins porate pure lipid bilayers through a mechanism sensitive to intrinsic monolayer curvature [J].
Basañez, G ;
Sharpe, JC ;
Galanis, J ;
Brandt, TB ;
Hardwick, JM ;
Zimmerberg, J .
JOURNAL OF BIOLOGICAL CHEMISTRY, 2002, 277 (51) :49360-49365
[4]   Cathepsin D triggers bax activation, resulting in selective apoptosis-inducing factor (AIF) relocation in T lymphocytes entering the early commitment phase to apoptosis [J].
Bidère, N ;
Lorenzo, HK ;
Carmona, S ;
Laforge, M ;
Harper, F ;
Dumont, C ;
Senik, A .
JOURNAL OF BIOLOGICAL CHEMISTRY, 2003, 278 (33) :31401-31411
[5]   A system for stable expression of short interfering RNAs in mammalian cells [J].
Brummelkamp, TR ;
Bernards, R ;
Agami, R .
SCIENCE, 2002, 296 (5567) :550-553
[6]   Nonredundant role of Bax and Bak in Bid-mediated apoptosis [J].
Cartron, PF ;
Juin, P ;
Oliver, L ;
Martin, S ;
Meflah, K ;
Vallette, FM .
MOLECULAR AND CELLULAR BIOLOGY, 2003, 23 (13) :4701-4712
[7]   Mitochondrially localized active caspase-9 and caspase-3 result mostly from translocation from the cytosol and partly from caspase-mediated activation in the organelle - Lack of evidence for Apaf-1-mediated procaspase-9 activation in the mitochondria [J].
Chandra, D ;
Tang, DG .
JOURNAL OF BIOLOGICAL CHEMISTRY, 2003, 278 (19) :17408-17420
[8]   Association of active caspase 8 with the mitochondrial membrane during apoptosis: Potential roles in cleaving BAP31 and caspase 3 and mediating mitochondrion-endoplasmic reticulum cross talk in etoposide-induced cell death [J].
Chandra, D ;
Choy, G ;
Deng, XD ;
Bhatia, B ;
Daniel, P ;
Tang, DG .
MOLECULAR AND CELLULAR BIOLOGY, 2004, 24 (15) :6592-6607
[9]   Early mitochondrial activation and cytochrome c up-regulation during apoptosis [J].
Chandra, D ;
Liu, JW ;
Tang, DG .
JOURNAL OF BIOLOGICAL CHEMISTRY, 2002, 277 (52) :50842-50854
[10]   VDAC2 inhibits BAK activation and mitochondrial apoptosis [J].
Cheng, EHY ;
Sheiko, TV ;
Fisher, JK ;
Craigen, WJ ;
Korsmeyer, SJ .
SCIENCE, 2003, 301 (5632) :513-517