Mutational Analysis of Fusion Peptide-Like Regions in the Mouse Hepatitis Virus Strain A59 Spike Protein

  • Zongli Luo
  • Susan R. Weiss
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 440)


The Coronavirus peplomer protein S is responsible for attachment and fusion during viral entry as well as for the induction of cell to cell fusion. While several regions within S have been shown to influence the ability to induce fusion, the region of the protein actu-ally responsible for fusion, the fusion peptide, has not yet been identified. We identified two hydrophobic peptides (peptides #1 and #2) within MHV-A59 S2 as possible fusion domains. This was based on hydrophobicity, conservation among coronavirus S proteins and the prediction of a sided helix conformation. Using site directed mutagenesis and an in vitro cell to cell fusion assay we showed that substitution of hydrophobic amino acids with charged amino acids, within the predicted hydrophobic face of either of these two peptides eliminated fusion. Within peptide #1 substitution of the same hydrophobic amino acids with other hydrophobic amino acids or substitution of polar amino acids with charged or polar amino acids had little effect on fusion. Thus peptides #1 and #2 remain likely candidates for the MHV fusion peptide. A third previously identified peptide within S2 (Chambers et al., 1990) is unlikely as a fusion peptide as it is not well conserved among coronaviruses and substitution within the hydrophobic face with charged amino ac-ids does not effect fusion.


Cell Fusion Hydrophobic Amino Acid Fusion Peptide Polar Amino Acid Heptad Repeat 
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  1. Bos, E. C. W., Heijnen, L., Luytjes, W., and Spaan, W. J. M., 1996, Mutational analysis of the murine coronavirus spike protein: effect on cell to cell fusion, Virology 214: 453–463.CrossRefGoogle Scholar
  2. Chambers, P, Pringle, C. R., and Easton, A. J., 1990, Heptad repeat sequences are located adjacent to hydrophobic regions in several types of virus fusion glycoproteins, J. Gen. Virol. 71: 3075–3080.PubMedCrossRefGoogle Scholar
  3. Gallagher, T. M., Parker, S. E., and Buchmeier, M. J., 1990, Neutralization resistant variants of a neurotropic coronavirus are generated by deletions within the amino terminal half of the spike glycoprotein, J. Virol. 64: 731–741.PubMedGoogle Scholar
  4. Gallagher, T. M., Escarmis, C, and Buchmeier, M. J., 1991, Alteration of pH dependence of coronavirus-induced cell fusion: Effect of mutations in the spike glycoprotein, J. Virol. 65: 1916–1928.PubMedGoogle Scholar
  5. Gallaher, W. R., Segrest, J. P., and Hunter, E., 1992, Are fusion peptides really “sided” insertional helices?Cell 70: 531–532.PubMedCrossRefGoogle Scholar
  6. Gombold, J. L., Hingley, S. T., and Weiss, S. R., 1993, Fusion-defective mutants of mouse hepatitis virusA59 contain a mutation in the spike protein cleavage signal, J. Virol. 67: 4504–4512.PubMedGoogle Scholar
  7. Hingley, S. T., Gombold, J. L., Lavi, E., and Weiss, S. R., 1994, MHV-A59 fusion mutants are attenuated and display altered hepatotropism, Virology 200: 1–10.PubMedCrossRefGoogle Scholar
  8. Landt, O., Grunert, H. P., and Hahn, U., 1990, A general method for rapid site directed mutagenesis, Gene 96: 125–128.PubMedCrossRefGoogle Scholar
  9. Nussbaum, O., Broder, C. C, and Berger, E. A., 1994, Fusogenic mechanisms of enveloped-virrus glycoproteins analyzeed by a novel recombinant vacciniavirus-based assay qunatitating cell fusion-dependent reporter gene activation, J. Virol. 68:5411–5422.PubMedGoogle Scholar
  10. Pereira, F. B., Goni, F. M., and Nieva, J. L., 1995, Liposome destabilization induced by the HIV fusion peptide: Effect of single aminom acid changes, FEBS Letters 362: 2243–246.CrossRefGoogle Scholar
  11. Taguchi, F., Ikeda, T., and Shida, H., 1992, Molecular cloning and expression of a spike protein of neurovirulent murine Coronavirus JHMV variant cl-2, J. Gen. Virol. 73: 1065–1072.PubMedCrossRefGoogle Scholar
  12. White, J., 1992, Membrane fusion, Science 258: 917–924.PubMedCrossRefGoogle Scholar
  13. White, J. M., 1990, Viral and cellular membrane fusion proteins, Ann. Rv. Physiol. 52: 675–697.CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media New York 1998

Authors and Affiliations

  • Zongli Luo
    • 1
  • Susan R. Weiss
    • 1
  1. 1.Department of MicrobiologyUniversity of Pennsylvania School of MedicinePhiladelphiaUSA

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