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PubMed · 7644501

Multiple Bcl-2 family members demonstrate selective dimerizations with Bax.

T W Sedlak·Z N Oltvai·E Yang·K Wang·L H Boise·C B Thompson·S J Korsmeyer
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Abstract

A family of Bcl-2-related proteins regulates cell death and shares highly conserved BH1 and BH2 domains. BH1 and BH2 domains of Bcl-2 were required for it to heterodimerize with Bax and to repress apoptosis. A yeast two-hybrid assay accurately reproduced this interaction and defined a selectivity and hierarchy of further dimerizations. Bax also heterodimerizes with Bcl-xL, Mcl-1, and A1. A Gly-159-->Ala substitution in BH1 of Bcl-xL disrupted its heterodimerization with Bax and abrogated its inhibition of apoptosis in mammalian cells. This suggests that the susceptibility to apoptosis is determined by multiple competing dimerizations in which Bax may be a common partner.

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Amino Acid SequenceAnimalsAntibodies, MonoclonalApoptosisCell LineCloning, MolecularConserved SequenceCricetinaeEscherichia coliGTP-Binding ProteinsHematopoietic Stem CellsInterleukin-3Macromolecular SubstancesMiceModels, BiologicalMutagenesis, Site-DirectedPoint MutationProto-Oncogene ProteinsProto-Oncogene Proteins c-bcl-2Recombinant ProteinsSaccharomyces cerevisiaeTransfectionbcl-2-Associated X Proteinbeta-GalactosidaseJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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T W Sedlak, Z N Oltvai, E Yang, K Wang, L H Boise, C B Thompson, S J Korsmeyer. 1995-08-15. Multiple Bcl-2 family members demonstrate selective dimerizations with Bax.. https://doi.org/10.1073/pnas.92.17.7834

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