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Solution structure and functional analysis of the influenza B proton channel

Abstract

Influenza B virus contains an integral membrane protein, BM2, that oligomerizes in the viral membrane to form a pH-activated proton channel. Here we report the solution structures of both the membrane-embedded channel domain and the cytoplasmic domain of BM2. The channel domain assumes a left-handed coiled-coil tetramer formation with a helical packing angle of −37° to form a polar pore in the membrane for conducting ions. Mutagenesis and proton flux experiments identified residues involved in proton relay and suggest a mechanism of proton conductance. The cytoplasmic domain of BM2 also forms a coiled-coil tetramer. It has a bipolar charge distribution, in which a negatively charged region interacts specifically with the M1 matrix protein that is involved in packaging the genome in the virion. This interaction suggests BM2 also recruits matrix proteins to the cell surface during virus budding, making BM2 an unusual membrane protein with the dual roles of conducting ions and recruiting proteins to the membrane.

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Figure 1: Solution structure of BM2 from influenza B virus.
Figure 2: Assembly of the H+ conducting pore.
Figure 3: Interaction between BM2 cytoplasmic domain and BM1 matrix protein.
Figure 4: The dual functionality of BM2.

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References

  1. Hatta, M., Goto, H. & Kawaoka, Y. Influenza B virus requires BM2 protein for replication. J. Virol. 78, 5576–5583 (2004).

    Article  CAS  Google Scholar 

  2. Pinto, L.H. & Lamb, R.A. The M2 proton channels of influenza A and B viruses. J. Biol. Chem. 281, 8997–9000 (2006).

    Article  CAS  Google Scholar 

  3. Hay, A.J., Wolstenholme, A.J., Skehel, J.J. & Smith, M.H. The molecular basis of the specific anti-influenza action of amantadine. EMBO J. 4, 3021–3024 (1985).

    Article  CAS  Google Scholar 

  4. Helenius, A. Unpacking the incoming influenza virus. Cell 69, 577–578 (1992).

    Article  CAS  Google Scholar 

  5. Paterson, R.G., Takeda, M., Ohigashi, Y., Pinto, L.H. & Lamb, R.A. Influenza B virus BM2 protein is an oligomeric integral membrane protein expressed at the cell surface. Virology 306, 7–17 (2003).

    Article  CAS  Google Scholar 

  6. Mould, J.A. et al. Influenza B virus BM2 protein has ion channel activity that conducts protons across membranes. Dev. Cell 5, 175–184 (2003).

    Article  CAS  Google Scholar 

  7. Pinto, L.H. et al. A functionally defined model for the M2 proton channel of influenza A virus suggests a mechanism for its ion selectivity. Proc. Natl. Acad. Sci. USA 94, 11301–11306 (1997).

    Article  CAS  Google Scholar 

  8. Kovacs, F.A., Denny, J.K., Song, Z., Quine, J.R. & Cross, T.A. Helix tilt of the M2 transmembrane peptide from influenza A virus: an intrinsic property. J. Mol. Biol. 295, 117–125 (2000).

    Article  CAS  Google Scholar 

  9. Kukol, A., Adams, P.D., Rice, L.M., Brunger, A.T. & Arkin, T.I. Experimentally based orientational refinement of membrane protein models: A structure for the influenza A M2 H+ channel. J. Mol. Biol. 286, 951–962 (1999).

    Article  CAS  Google Scholar 

  10. Schnell, J.R. & Chou, J.J. Structure and mechanism of the M2 proton channel of influenza A virus. Nature 451, 591–595 (2008).

    Article  CAS  Google Scholar 

  11. Wang, J., Kim, S., Kovacs, F. & Cross, T.A. Structure of the transmembrane region of the M2 protein H+ channel. Protein Sci. 10, 2241–2250 (2001).

    Article  CAS  Google Scholar 

  12. Stouffer, A.L. et al. Structural basis for the function and inhibition of an influenza virus proton channel. Nature 451, 596–599 (2008).

    Article  CAS  Google Scholar 

  13. Ma, C. et al. Identification of the pore-lining residues of the BM2 ion channel protein of influenza B virus. J. Biol. Chem. 283, 15921–15931 (2008).

    Article  CAS  Google Scholar 

  14. Chen, B.J., Leser, G.P., Jackson, D. & Lamb, R.A. The influenza virus M2 protein cytoplasmic tail interacts with the M1 protein and influences virus assembly at the site of virus budding. J. Virol. 82, 10059–10070 (2008).

    Article  CAS  Google Scholar 

  15. McCown, M.F. & Pekosz, A. Distinct domains of the influenza a virus M2 protein cytoplasmic tail mediate binding to the M1 protein and facilitate infectious virus production. J. Virol. 80, 8178–8189 (2006).

    Article  CAS  Google Scholar 

  16. Imai, M., Kawasaki, K. & Odagiri, T. Cytoplasmic domain of influenza B virus BM2 protein plays critical roles in production of infectious virus. J. Virol. 82, 728–739 (2008).

    Article  CAS  Google Scholar 

  17. Imai, M., Watanabe, S., Ninomiya, A., Obuchi, M. & Odagiri, T. Influenza B virus BM2 protein is a crucial component for incorporation of viral ribonucleoprotein complex into virions during virus assembly. J. Virol. 78, 11007–11015 (2004).

    Article  CAS  Google Scholar 

  18. Pielak, R.M., Schnell, J.R. & Chou, J.J. Mechanism of drug inhibition and drug resistance of influenza A M2 channel. Proc. Natl. Acad. Sci. USA 106, 7379–7384 (2009).

    Article  CAS  Google Scholar 

  19. Xu, C. et al. Regulation of T cell receptor activation by dynamic membrane binding of the CD3epsilon cytoplasmic tyrosine-based motif. Cell 135, 702–713 (2008).

    Article  CAS  Google Scholar 

  20. Harbury, P.B., Zhang, T., Kim, P.S. & Alber, T. A switch between two-, three-, and four-stranded coiled coils in GCN4 leucine zipper mutants. Science 262, 1401–1407 (1993).

    Article  CAS  Google Scholar 

  21. Felder, C., Prilusky, J., Silman, I. & Sussman, J. A server and database for dipole moments of proteins. Nucleic Acids Res. 35 (special Web Servers Issue) (2007).

  22. Sha, B. & Luo, M. Structure of a bifunctional membrane-RNA binding protein, influenza virus matrix protein M1. Nat. Struct. Biol. 4, 239–244 (1997).

    Article  CAS  Google Scholar 

  23. Otomo, K., Toyama, A., Miura, T. & Takeuchi, H. Interactions between histidine and tryptophan residues in the BM2 proton channel from influenza B virus. J. Biochem. 145, 543–554 (2009).

    Article  CAS  Google Scholar 

  24. Du, Q.S., Huang, R.B., Wang, C.H., Li, X.M. & Chou, K.C. Energetic analysis of the two controversial drug binding sites of the M2 proton channel in influenza A virus. J. Theor. Biol. 259, 159–164 (2009).

    Article  CAS  Google Scholar 

  25. Chou, J.J., Matsuo, H., Duan, H. & Wagner, G. Solution structure of the RAIDD CARD and model for CARD/CARD interaction in caspase-2 and caspase-9 recruitment. Cell 94, 171–180 (1998).

    Article  CAS  Google Scholar 

  26. Smart, O.S., Goodfellow, J.M. & Wallace, B.A. The pore dimensions of gramicidin A. Biophys. J. 65, 2455–2460 (1993).

    Article  CAS  Google Scholar 

  27. Bax, A. et al. Measurement of homo- and heteronuclear J couplings from quantitative J correlation. Methods Enzymol. 239, 79–105 (1994).

    Article  CAS  Google Scholar 

  28. Lorieau, J., Yao, L. & Bax, A. Liquid crystalline phase of G-tetrad DNA for NMR study of detergent-solubilized proteins. J. Am. Chem. Soc. 130, 7536–7537 (2008).

    Article  CAS  Google Scholar 

  29. Schwieters, C.D., Kuszewski, J., Tjandra, N. & Clore, G.M. The Xplor-NIH NMR molecular structure determination package. J. Magn. Reson. 160, 66–74 (2002).

    Google Scholar 

  30. Cornilescu, G., Delaglio, F. & Bax, A. Protein backbone angle restraints from searching a database for chemical shift and sequence homology. J. Biomol. NMR 13, 289–302 (1999).

    Article  CAS  Google Scholar 

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Acknowledgements

We thank M. Berardi for insightful discussion on the interaction between BM2 and M1 matrix protein. This work was supported by grants from the US National Institutes of Health (AI054520 to J.J.C.) and the Pew Scholars Program in Biomedical Sciences to J.J.C.

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Contributions

J.W. and J.J.C. determined the BM2 structures; R.M.P. performed proton conductance assays; J.W. and M.A.M. performed the BM2-BM1 interaction experiment; J.J.C., R.M.P. and J.W. wrote the paper; J.J.C. supervised the research.

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Correspondence to James J Chou.

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Supplementary Methods and Supplementary Figures 1–13 (PDF 1363 kb)

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Wang, J., Pielak, R., McClintock, M. et al. Solution structure and functional analysis of the influenza B proton channel. Nat Struct Mol Biol 16, 1267–1271 (2009). https://doi.org/10.1038/nsmb.1707

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