Bax Monomers Form Dimer Units in the Membrane That Further Self-assemble into Multiple Oligomeric Species

Overview

Journal Nat Commun

Specialty Biology

Date 2015 Aug 15

PMID 26271728

Citations 87

Authors

Yamunadevi Subburaj

Katia Cosentino

Markus Axmann

Esteban Pedrueza-Villalmanzo

Eduard Hermann

Stephanie Bleicken

Joachim Spatz

Ana J Garcia-Saez

Affiliations

Soon will be listed here.

Abstract

Bax is a key regulator of apoptosis that mediates the release of cytochrome c to the cytosol via oligomerization in the outer mitochondrial membrane before pore formation. However, the molecular mechanism of Bax assembly and regulation by other Bcl-2 members remains obscure. Here, by analysing the stoichiometry of Bax oligomers at the single-molecule level, we find that Bax binds to the membrane in a monomeric state and then self-assembles in <1 min. Strikingly, active Bax does not exist in a unique oligomeric state, but as several different species based on dimer units. Moreover, we show that cBid activates Bax without affecting its assembly, while Bcl-xL induces the dissociation of Bax oligomers. On the basis of our experimental data and theoretical modelling, we propose a new mechanism for the molecular pathway of Bax assembly to form the apoptotic pore.

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References

Hastie P, Ulbrich M, Wang H, Arant R, Lau A, Zhang Z . AMPA receptor/TARP stoichiometry visualized by single-molecule subunit counting. Proc Natl Acad Sci U S A. 2013; 110(13):5163-8. PMC: 3612642. DOI: 10.1073/pnas.1218765110. View

Desagher S, Osen-Sand A, Nichols A, Eskes R, Montessuit S, Lauper S . Bid-induced conformational change of Bax is responsible for mitochondrial cytochrome c release during apoptosis. J Cell Biol. 1999; 144(5):891-901. PMC: 2148190. DOI: 10.1083/jcb.144.5.891. View

Moldoveanu T, Grace C, Llambi F, Nourse A, Fitzgerald P, Gehring K . BID-induced structural changes in BAK promote apoptosis. Nat Struct Mol Biol. 2013; 20(5):589-97. PMC: 3683554. DOI: 10.1038/nsmb.2563. View

Xu X, Zhai D, Kim E, Swift M, Reed J, Volkmann N . Three-dimensional structure of Bax-mediated pores in membrane bilayers. Cell Death Dis. 2013; 4:e683. PMC: 3702287. DOI: 10.1038/cddis.2013.210. View

Deeg J, Axmann M, Matic J, Liapis A, Depoil D, Afrose J . T cell activation is determined by the number of presented antigens. Nano Lett. 2013; 13(11):5619-26. PMC: 3828117. DOI: 10.1021/nl403266t. View

Bleicken S, Landeta O, Landajuela A, Basanez G, Garcia-Saez A . Proapoptotic Bax and Bak proteins form stable protein-permeable pores of tunable size. J Biol Chem. 2013; 288(46):33241-52. PMC: 3829170. DOI: 10.1074/jbc.M113.512087. View

Czabotar P, Lessene G, Strasser A, Adams J . Control of apoptosis by the BCL-2 protein family: implications for physiology and therapy. Nat Rev Mol Cell Biol. 2013; 15(1):49-63. DOI: 10.1038/nrm3722. View

Unsay J, Cosentino K, Subburaj Y, Garcia-Saez A . Cardiolipin effects on membrane structure and dynamics. Langmuir. 2013; 29(51):15878-87. DOI: 10.1021/la402669z. View

Aluvila S, Mandal T, Hustedt E, Fajer P, Choe J, Oh K . Organization of the mitochondrial apoptotic BAK pore: oligomerization of the BAK homodimers. J Biol Chem. 2013; 289(5):2537-51. PMC: 3908389. DOI: 10.1074/jbc.M113.526806. View

10.

Anderluh A, Klotzsch E, Reismann A, Brameshuber M, Kudlacek O, Newman A . Single molecule analysis reveals coexistence of stable serotonin transporter monomers and oligomers in the live cell plasma membrane. J Biol Chem. 2014; 289(7):4387-94. PMC: 3924301. DOI: 10.1074/jbc.M113.531632. View

11.

Hoffmann M, Schwarz U . Oscillations of Min-proteins in micropatterned environments: a three-dimensional particle-based stochastic simulation approach. Soft Matter. 2014; 10(14):2388-96. DOI: 10.1039/c3sm52251b. View

12.

Ding J, Mooers B, Zhang Z, Kale J, Falcone D, McNichol J . After embedding in membranes antiapoptotic Bcl-XL protein binds both Bcl-2 homology region 3 and helix 1 of proapoptotic Bax protein to inhibit apoptotic mitochondrial permeabilization. J Biol Chem. 2014; 289(17):11873-11896. PMC: 4002096. DOI: 10.1074/jbc.M114.552562. View

13.

Hermann E, Bleicken S, Subburaj Y, Garcia-Saez A . Automated analysis of giant unilamellar vesicles using circular Hough transformation. Bioinformatics. 2014; 30(12):1747-54. DOI: 10.1093/bioinformatics/btu102. View

14.

Bleicken S, Jeschke G, Stegmueller C, Salvador-Gallego R, Garcia-Saez A, Bordignon E . Structural model of active Bax at the membrane. Mol Cell. 2014; 56(4):496-505. PMC: 4869853. DOI: 10.1016/j.molcel.2014.09.022. View

15.

Antonsson B, Montessuit S, Lauper S, Eskes R, Martinou J . Bax oligomerization is required for channel-forming activity in liposomes and to trigger cytochrome c release from mitochondria. Biochem J. 2000; 345 Pt 2:271-8. PMC: 1220756. View

16.

Eskes R, Desagher S, Antonsson B, Martinou J . Bid induces the oligomerization and insertion of Bax into the outer mitochondrial membrane. Mol Cell Biol. 2000; 20(3):929-35. PMC: 85210. DOI: 10.1128/MCB.20.3.929-935.2000. View

17.

Edlich F, Banerjee S, Suzuki M, Cleland M, Arnoult D, Wang C . Bcl-x(L) retrotranslocates Bax from the mitochondria into the cytosol. Cell. 2011; 145(1):104-16. PMC: 3070914. DOI: 10.1016/j.cell.2011.02.034. View

18.

Meckel T, Semrau S, Schaaf M, Schmidt T . Robust assessment of protein complex formation in vivo via single-molecule intensity distributions of autofluorescent proteins. J Biomed Opt. 2011; 16(7):076016. DOI: 10.1117/1.3600002. View

19.

Llambi F, Moldoveanu T, Tait S, Bouchier-Hayes L, Temirov J, McCormick L . A unified model of mammalian BCL-2 protein family interactions at the mitochondria. Mol Cell. 2011; 44(4):517-31. PMC: 3221787. DOI: 10.1016/j.molcel.2011.10.001. View

20.

Reuel N, Bojo P, Zhang J, Boghossian A, Ahn J, Kim J . NoRSE: noise reduction and state evaluator for high-frequency single event traces. Bioinformatics. 2011; 28(2):296-7. DOI: 10.1093/bioinformatics/btr632. View