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. 1992 Jan 2;116(2):339–348. doi: 10.1083/jcb.116.2.339

Membrane fusion process of Semliki Forest virus. I: Low pH-induced rearrangement in spike protein quaternary structure precedes virus penetration into cells

PMCID: PMC2289294  PMID: 1370493

Abstract

The Semliki Forest virus (SFV) directs the synthesis of a heterodimeric membrane protein complex which is used for virus membrane assembly during budding at the surface of the infected cell, as well as for low pH-induced membrane fusion in the endosomes when particles enter new host cells. Existing evidence suggests that the E1 protein subunit carries the fusion potential of the heterodimer, whereas the E2 subunit, or its intracellular precursor p62, is required for binding to the nucleocapsid. We show here that during virus uptake into acidic endosomes the original E2E1 heterodimer is destabilized and the E1 proteins form new oligomers, presumably homooligomers, with altered E1 structure. This altered structure of E1 is specifically recognized by a monoclonal antibody which can also inhibit penetration of SFV into host cells as well as SFV-mediated cell-cell fusion, thus suggesting that the altered E1 structure is important for the membrane fusion. These results give further support for a membrane protein oligomerization- mediated control mechanism for the membrane fusion potential in alphaviruses.

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Selected References

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  1. Anderson R. G., Orci L. A view of acidic intracellular compartments. J Cell Biol. 1988 Mar;106(3):539–543. doi: 10.1083/jcb.106.3.539. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Boere W. A., Harmsen T., Vinjé J., Benaissa-Trouw B. J., Kraaijeveld C. A., Snippe H. Identification of distinct antigenic determinants on Semliki Forest virus by using monoclonal antibodies with different antiviral activities. J Virol. 1984 Nov;52(2):575–582. doi: 10.1128/jvi.52.2.575-582.1984. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Boggs W. M., Hahn C. S., Strauss E. G., Strauss J. H., Griffin D. E. Low pH-dependent Sindbis virus-induced fusion of BHK cells: differences between strains correlate with amino acid changes in the E1 glycoprotein. Virology. 1989 Apr;169(2):485–488. doi: 10.1016/0042-6822(89)90178-5. [DOI] [PubMed] [Google Scholar]
  4. Chamberlain J. P. Fluorographic detection of radioactivity in polyacrylamide gels with the water-soluble fluor, sodium salicylate. Anal Biochem. 1979 Sep 15;98(1):132–135. doi: 10.1016/0003-2697(79)90716-4. [DOI] [PubMed] [Google Scholar]
  5. Cutler D. F., Garoff H. Mutants of the membrane-binding region of Semliki Forest virus E2 protein. I. Cell surface transport and fusogenic activity. J Cell Biol. 1986 Mar;102(3):889–901. doi: 10.1083/jcb.102.3.889. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Dalgarno L., Rice C. M., Strauss J. H. Ross River virus 26 s RNA: complete nucleotide sequence and deduced sequence of the encoded structural proteins. Virology. 1983 Aug;129(1):170–187. doi: 10.1016/0042-6822(83)90404-x. [DOI] [PubMed] [Google Scholar]
  7. Edwards J., Mann E., Brown D. T. Conformational changes in Sindbis virus envelope proteins accompanying exposure to low pH. J Virol. 1983 Mar;45(3):1090–1097. doi: 10.1128/jvi.45.3.1090-1097.1983. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Flynn D. C., Meyer W. J., Mackenzie J. M., Jr, Johnston R. E. A conformational change in Sindbis virus glycoproteins E1 and E2 is detected at the plasma membrane as a consequence of early virus-cell interaction. J Virol. 1990 Aug;64(8):3643–3653. doi: 10.1128/jvi.64.8.3643-3653.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Fuller S. D. The T=4 envelope of Sindbis virus is organized by interactions with a complementary T=3 capsid. Cell. 1987 Mar 27;48(6):923–934. doi: 10.1016/0092-8674(87)90701-x. [DOI] [PubMed] [Google Scholar]
  10. Garoff H., Frischauf A. M., Simons K., Lehrach H., Delius H. Nucleotide sequence of cdna coding for Semliki Forest virus membrane glycoproteins. Nature. 1980 Nov 20;288(5788):236–241. doi: 10.1038/288236a0. [DOI] [PubMed] [Google Scholar]
  11. Garoff H., Kondor-Koch C., Riedel H. Structure and assembly of alphaviruses. Curr Top Microbiol Immunol. 1982;99:1–50. doi: 10.1007/978-3-642-68528-6_1. [DOI] [PubMed] [Google Scholar]
  12. Garoff H., Simons K. Location of the spike glycoproteins in the Semliki Forest virus membrane. Proc Natl Acad Sci U S A. 1974 Oct;71(10):3988–3992. doi: 10.1073/pnas.71.10.3988. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Helenius A., Fries E., Garoff H., Simons K. Solubilization of the Semliki Forest virus membrane with sodium deoxycholate. Biochim Biophys Acta. 1976 Jun 17;436(2):319–334. doi: 10.1016/0005-2736(76)90197-8. [DOI] [PubMed] [Google Scholar]
  14. Helenius A., Kartenbeck J., Simons K., Fries E. On the entry of Semliki forest virus into BHK-21 cells. J Cell Biol. 1980 Feb;84(2):404–420. doi: 10.1083/jcb.84.2.404. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Helenius A., Kielian M., Wellsteed J., Mellman I., Rudnick G. Effects of monovalent cations on Semliki Forest virus entry into BHK-21 cells. J Biol Chem. 1985 May 10;260(9):5691–5697. [PubMed] [Google Scholar]
  16. Kielian M. C., Helenius A. Role of cholesterol in fusion of Semliki Forest virus with membranes. J Virol. 1984 Oct;52(1):281–283. doi: 10.1128/jvi.52.1.281-283.1984. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Kielian M. C., Marsh M., Helenius A. Kinetics of endosome acidification detected by mutant and wild-type Semliki Forest virus. EMBO J. 1986 Dec 1;5(12):3103–3109. doi: 10.1002/j.1460-2075.1986.tb04616.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Kielian M., Helenius A. pH-induced alterations in the fusogenic spike protein of Semliki Forest virus. J Cell Biol. 1985 Dec;101(6):2284–2291. doi: 10.1083/jcb.101.6.2284. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Kielian M., Jungerwirth S., Sayad K. U., DeCandido S. Biosynthesis, maturation, and acid activation of the Semliki Forest virus fusion protein. J Virol. 1990 Oct;64(10):4614–4624. doi: 10.1128/jvi.64.10.4614-4624.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. LOWRY O. H., ROSEBROUGH N. J., FARR A. L., RANDALL R. J. Protein measurement with the Folin phenol reagent. J Biol Chem. 1951 Nov;193(1):265–275. [PubMed] [Google Scholar]
  21. Lobigs M., Garoff H. Fusion function of the Semliki Forest virus spike is activated by proteolytic cleavage of the envelope glycoprotein precursor p62. J Virol. 1990 Mar;64(3):1233–1240. doi: 10.1128/jvi.64.3.1233-1240.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Lobigs M., Wahlberg J. M., Garoff H. Spike protein oligomerization control of Semliki Forest virus fusion. J Virol. 1990 Oct;64(10):5214–5218. doi: 10.1128/jvi.64.10.5214-5218.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Marsh M., Helenius A. Adsorptive endocytosis of Semliki Forest virus. J Mol Biol. 1980 Sep 25;142(3):439–454. doi: 10.1016/0022-2836(80)90281-8. [DOI] [PubMed] [Google Scholar]
  24. Marsh M., Wellsteed J., Kern H., Harms E., Helenius A. Monensin inhibits Semliki Forest virus penetration into culture cells. Proc Natl Acad Sci U S A. 1982 Sep;79(17):5297–5301. doi: 10.1073/pnas.79.17.5297. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Metsikkö K., Garoff H. Oligomers of the cytoplasmic domain of the p62/E2 membrane protein of Semliki Forest virus bind to the nucleocapsid in vitro. J Virol. 1990 Oct;64(10):4678–4683. doi: 10.1128/jvi.64.10.4678-4683.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Omar A., Koblet H. Semliki Forest virus particles containing only the E1 envelope glycoprotein are infectious and can induce cell-cell fusion. Virology. 1988 Sep;166(1):17–23. doi: 10.1016/0042-6822(88)90141-9. [DOI] [PubMed] [Google Scholar]
  27. Persson R., Pettersson R. F. Formation and intracellular transport of a heterodimeric viral spike protein complex. J Cell Biol. 1991 Jan;112(2):257–266. doi: 10.1083/jcb.112.2.257. [DOI] [PMC free article] [PubMed] [Google Scholar]
  28. Rice C. M., Strauss J. H. Nucleotide sequence of the 26S mRNA of Sindbis virus and deduced sequence of the encoded virus structural proteins. Proc Natl Acad Sci U S A. 1981 Apr;78(4):2062–2066. doi: 10.1073/pnas.78.4.2062. [DOI] [PMC free article] [PubMed] [Google Scholar]
  29. Salminen A., Wahlberg J. M., Lobigs M., Liljeström P., Garoff H. Membrane fusion process of Semliki Forest virus. II: Cleavage-dependent reorganization of the spike protein complex controls virus entry. J Cell Biol. 1992 Jan;116(2):349–357. doi: 10.1083/jcb.116.2.349. [DOI] [PMC free article] [PubMed] [Google Scholar]
  30. Simons K., Helenius A., Garoff H. Solubilization of the membrane proteins from Semliki Forest virus with Triton X100. J Mol Biol. 1973 Oct 15;80(1):119–133. doi: 10.1016/0022-2836(73)90236-2. [DOI] [PubMed] [Google Scholar]
  31. Stegmann T., Doms R. W., Helenius A. Protein-mediated membrane fusion. Annu Rev Biophys Biophys Chem. 1989;18:187–211. doi: 10.1146/annurev.bb.18.060189.001155. [DOI] [PubMed] [Google Scholar]
  32. Stegmann T., White J. M., Helenius A. Intermediates in influenza induced membrane fusion. EMBO J. 1990 Dec;9(13):4231–4241. doi: 10.1002/j.1460-2075.1990.tb07871.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  33. Vaux D. J., Helenius A., Mellman I. Spike--nucleocapsid interaction in Semliki Forest virus reconstructed using network antibodies. Nature. 1988 Nov 3;336(6194):36–42. doi: 10.1038/336036a0. [DOI] [PubMed] [Google Scholar]
  34. Vogel R. H., Provencher S. W., von Bonsdorff C. H., Adrian M., Dubochet J. Envelope structure of Semliki Forest virus reconstructed from cryo-electron micrographs. Nature. 1986 Apr 10;320(6062):533–535. doi: 10.1038/320533a0. [DOI] [PubMed] [Google Scholar]
  35. Wahlberg J. M., Boere W. A., Garoff H. The heterodimeric association between the membrane proteins of Semliki Forest virus changes its sensitivity to low pH during virus maturation. J Virol. 1989 Dec;63(12):4991–4997. doi: 10.1128/jvi.63.12.4991-4997.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
  36. Wengler G., Wengler G. Cell-associated West Nile flavivirus is covered with E+pre-M protein heterodimers which are destroyed and reorganized by proteolytic cleavage during virus release. J Virol. 1989 Jun;63(6):2521–2526. doi: 10.1128/jvi.63.6.2521-2526.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
  37. White J. M. Viral and cellular membrane fusion proteins. Annu Rev Physiol. 1990;52:675–697. doi: 10.1146/annurev.ph.52.030190.003331. [DOI] [PubMed] [Google Scholar]
  38. White J., Helenius A. pH-dependent fusion between the Semliki Forest virus membrane and liposomes. Proc Natl Acad Sci U S A. 1980 Jun;77(6):3273–3277. doi: 10.1073/pnas.77.6.3273. [DOI] [PMC free article] [PubMed] [Google Scholar]
  39. White J., Kartenbeck J., Helenius A. Fusion of Semliki forest virus with the plasma membrane can be induced by low pH. J Cell Biol. 1980 Oct;87(1):264–272. doi: 10.1083/jcb.87.1.264. [DOI] [PMC free article] [PubMed] [Google Scholar]
  40. White J., Matlin K., Helenius A. Cell fusion by Semliki Forest, influenza, and vesicular stomatitis viruses. J Cell Biol. 1981 Jun;89(3):674–679. doi: 10.1083/jcb.89.3.674. [DOI] [PMC free article] [PubMed] [Google Scholar]
  41. Ziemiecki A., Garoff H., Simons K. Formation of the Semliki Forest virus membrane glycoprotein complexes in the infected cell. J Gen Virol. 1980 Sep;50(1):111–123. doi: 10.1099/0022-1317-50-1-111. [DOI] [PubMed] [Google Scholar]
  42. de Curtis I., Simons K. Dissection of Semliki Forest virus glycoprotein delivery from the trans-Golgi network to the cell surface in permeabilized BHK cells. Proc Natl Acad Sci U S A. 1988 Nov;85(21):8052–8056. doi: 10.1073/pnas.85.21.8052. [DOI] [PMC free article] [PubMed] [Google Scholar]

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