The Destabilization of Lipid Membranes Induced by the C-terminal Fragment of Caspase 8-cleaved Bid Is Inhibited by the N-terminal Fragment
| Autor: | Grzegorz Kudla, Alexandre Ghazi, Bruno Antonsson, Catherine Berrier, Jean-Claude Martinou, Sylvie Montessuit, Robert Eskes |
|---|---|
| Rok vydání: | 2000 |
| Předmět: |
Lipid Bilayers
urologic and male genital diseases Caspase 8 Cleavage (embryo) Biochemistry Mice Animals heterocyclic compounds Lipid bilayer neoplasms Molecular Biology Caspase-9 Liposome biology Chemistry Hydrolysis Cytochrome c Cell Biology Caspase 9 Recombinant Proteins digestive system diseases Mitochondria Cell biology Cytosol Proto-Oncogene Proteins c-bcl-2 Apoptosis Caspases Liposomes Mutation biology.protein biological phenomena cell phenomena and immunity Carrier Proteins BH3 Interacting Domain Death Agonist Protein |
| Zdroj: | Journal of Biological Chemistry. 275:22713-22718 |
| ISSN: | 0021-9258 |
| DOI: | 10.1074/jbc.m003807200 |
| Popis: | Bid is a proapoptotic, BH3-domain-only member of the Bcl-2 family. In Fas-induced apoptosis, Bid is activated through cleavage by caspase 8 into a 15.5-kDa C-terminal fragment (t(c)Bid) and a 6.5 kDa N-terminal fragment (t(n)Bid). Following the cleavage, t(c)Bid translocates to the mitochondria and promotes the release of cytochrome c into the cytosol by a mechanism that is not understood. Here we report that recombinant t(c)Bid can act as a membrane destabilizing agent. t(c)Bid induces destabilization and breaking of planar lipid bilayers without appearance of ionic channels; its destabilizing activity is comparable with that of Bax and at least 30-fold higher than that of full-length Bid. Consistently, t(c)Bid, but not full-length Bid, permeabilizes liposomes at physiological pH. The destabilizing effect of t(c)Bid on liposomes and planar bilayers is independent of the BH3 domain. In contrast, mutations in the BH3 domain impair t(c)Bid ability to induce cytochrome c release from mitochondria. The permeabilizing effect of t(c)Bid on planar bilayers, liposomes, and mitochondria can be inhibited by t(n)Bid. In conclusion, our results suggest a dual role for Bid: BH3-independent membrane destabilization and BH3-dependent interaction with other proteins. Moreover, the dissociation of Bid after cleavage by caspase 8 represents an additional step at which apoptosis may be regulated. |
| Databáze: | OpenAIRE |
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