Bcl-xS can form homodimers and heterodimers and its apoptotic activity requires localization of Bcl-xS to the mitochondria and its BH3 and loop domains

被引:33
作者
Lindenboim, L
Borner, C
Stein, R [1 ]
机构
[1] Tel Aviv Univ, Dept Neurobiochem, George S Wise Fac Life Sci, IL-69978 Ramat Aviv, Israel
[2] Univ Freiburg, Inst Mol Med & Cell Res, Zent Klin Forsch, D-79106 Freiburg, Germany
关键词
Bcl-x(S); mutations; dimerization; mitochondria; apoptosis; PC12; cells;
D O I
10.1038/sj.cdd.4400888
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
Proteins of the Bcl-2 family regulate apoptosis, some antagonizing cell death and others, such as Bcl-x(S), promoting it. We previously showed that expression of Bcl-x(S) in PC12 cells is a useful system for studying the mechanism of Bcl-x(S)-induced apoptosis. To further investigate this apoptotic effect and its prevention by anti-apoptotic agents, we assessed the role of distinct Bcl-x(S) domains, via the study of their mutations, on the ability of Bcl-x(S) to induce apoptosis and to localize to the mitochondria, as well as the ability of these domains to counteract the effects of anti-apoptotic agents on Bcl-x(S). Deletion of the transmembrane domain (Delta TM) prevented the localization of Bcl-x(S) Delta TM to the mitochondria and the ability of this mutant to induce apoptosis. Deletion of the amino acids GD 94 - 95 from the BH3 domain, or deletion of the loop region, impaired the ability of these mutants to induce apoptosis but not their localization to the mitochondria. Deletion of the BH4 domain or destruction of the caspase cleavage site in the loop region (by replacing amino acid D61 with A61) did not affect either the localization of these mutants to the mitochondria or their ability to induce cell death. It thus appears that Bcl-x(S)-induced apoptosis in PC12 cells is mediated by localization of Bcl-x(S) to the mitochondria by a process that requires the transmembrane domain. Furthermore, once localized to the mitochondria Bcl-x(S) requires the BH3 domain, and to a lesser extent the loop domain, for its subsequent activity. The anti-apoptotic agents Bcl-2 and Bcl-x(L), the caspase inhibitor Z-VAD-FMK, and nerve growth factor (NGF) did not prevent Bcl-x(S) localization to the mitochondria, and did not require the BH4 or the loop domains of Bcl-x(S) for their survival effect. Bcl-x(S) is capable of forming homodimers with itself and heterodimers with Bcl-x(L) or Bcl-2. Accordingly co-expression of Bcl-x(S) ATM with Bcl-x(S), Bcl-2, or Bcl-x(L) leads to a change in the subcellular distribution of Bcl-x(S) Delta TM, from a diffuse distribution throughout the cell to a more defined distribution. Moreover co-immunoprecipitation experiments directly demonstrated that Bcl-x(S) can associate with GFP-Bcl-x(S), Bcl-x(L), or Bcl-2. These results suggest that such Bcl-x(S) interactions may be important for the mechanism of action of this protein.
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收藏
页码:933 / 942
页数:10
相关论文
共 47 条
[1]   SECRETED PLACENTAL ALKALINE-PHOSPHATASE - A POWERFUL NEW QUANTITATIVE INDICATOR OF GENE-EXPRESSION IN EUKARYOTIC CELLS [J].
BERGER, J ;
HAUBER, J ;
HAUBER, R ;
GEIGER, R ;
CULLEN, BR .
GENE, 1988, 66 (01) :1-10
[2]   BCL-X, A BCL-2-RELATED GENE THAT FUNCTIONS AS A DOMINANT REGULATOR OF APOPTOTIC CELL-DEATH [J].
BOISE, LH ;
GONZALEZGARCIA, M ;
POSTEMA, CE ;
DING, LY ;
LINDSTEN, T ;
TURKA, LA ;
MAO, XH ;
NUNEZ, G ;
THOMPSON, CB .
CELL, 1993, 74 (04) :597-608
[3]  
BOYD JM, 1995, ONCOGENE, V11, P1921
[4]  
Chang BS, 1999, MOL CELL BIOL, V19, P6673
[5]   Identification of a novel regulatory domain in Bcl-x(L) and Bcl-2 [J].
Chang, BS ;
Minn, AJ ;
Muchmore, SW ;
Fesik, SW ;
Thompson, CB .
EMBO JOURNAL, 1997, 16 (05) :968-977
[6]   Nix and Nip3 form a subfamily of pro-apoptotic mitochondrial proteins [J].
Chen, G ;
Cizeau, J ;
Velde, CV ;
Park, JH ;
Bozek, G ;
Bolton, J ;
Shi, L ;
Dubik, D ;
Greenberg, A .
JOURNAL OF BIOLOGICAL CHEMISTRY, 1999, 274 (01) :7-10
[7]   A RECOMBINANT BCL-X(S) ADENOVIRUS SELECTIVELY INDUCES APOPTOSIS IN CANCER-CELLS BUT NOT IN NORMAL BONE-MARROW CELLS [J].
CLARKE, MF ;
APEL, IJ ;
BENEDICT, MA ;
EIPERS, PG ;
SUMANTRAN, V ;
GONZALEZGARCIA, M ;
DOEDENS, M ;
FUKUNAGA, N ;
DAVIDSON, B ;
DICK, JE ;
MINN, AJ ;
BOISE, LH ;
THOMPSON, CB ;
WICHA, M ;
NUNEZ, G .
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 1995, 92 (24) :11024-11028
[8]   Modulation of cell death by Bcl-xL through caspase interaction [J].
Clem, RJ ;
Cheng, EHY ;
Karp, CL ;
Kirsch, DG ;
Ueno, K ;
Takahashi, A ;
Kastan, MB ;
Griffin, DE ;
Earnshaw, WC ;
Veliuona, MA ;
Hardwick, JM .
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 1998, 95 (02) :554-559
[9]   Linkage of the BH4 domain of Bcl-2 and the nuclear factor κB signaling pathway for suppression of apoptosis [J].
de Moissac, D ;
Zheng, H ;
Kirshenbaum, LA .
JOURNAL OF BIOLOGICAL CHEMISTRY, 1999, 274 (41) :29505-29509
[10]   Bcl-Xshort is elevated following severe global ischemia in rat brains [J].
Dixon, EP ;
Stephenson, DT ;
Clemens, JA ;
Little, SP .
BRAIN RESEARCH, 1997, 776 (1-2) :222-229