Skip to main content
Log in

The fragmentation of incoming Semliki Forest virus nucleocapsids in mosquito (Aedes Albopictus) cells might be coupled to virion uncoating

  • Original Papers
  • Published:
Archives of Virology Aims and scope Submit manuscript

Summary

The fate of Semliki Forest virus (SFV) nucleocapsid, especially the capsid protein (C-protein), was investigated during the early stages of a productive infection in mosquitoAedes albopictus cells. Infection of the cells resulted in a time dependent accumulation of a C-protein derived fragment. This fragmentation of incoming viral nucleocapsid was prevented by NH4Cl, an agent generally used to elevate the pH in acidic intracellular compartments, suggesting that a low intravesicular pH is required for this process. Density gradient analysis of the postnuclear cell lysate demonstrated that the fragmentation was associated with a cellular compartment showing a density of 1.14±0.02 g/ml. This cellular compartment was devoid from a lysosomal marker enzyme and represented the timely preceding cellular fraction through which SFV passed before encountering a lysosomal fraction. Furthermore, the intracellular distribution of the viral,3H-uridine-labeled RNA suggested that the same fraction might represent a key cellular compartment in which the separation of the viral RNA from the viral structural proteins is primed. In conclusion, these data lead to the suggestion that the fragmentation of incoming SFV nucleocapsids inAedes albopictus cells might be the part of the mechanism leading to the release of viral RNA into the cytosol during early stages of productive infection.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  1. Coombs K, Brown B, Brown DT (1984) Evidence for a change in capsid morphology during Sindbis virus envelopment. Virus Res 1: 297–302

    Google Scholar 

  2. Froschauer S, Kartenbeck J, Helenius A (1988) Alphavirus RNA replicase is located on the cytoplasmic surface of endosomes and lysosomes. J Cell Biol 107: 2075–2086

    Google Scholar 

  3. Geigenmüller-Gnirke U, Nitschko H, Schlesinger S (1993) Deletion analysis of the capsid protein of Sindbis virus: identification of the RNA binding region. J Virol 67: 1620–1626

    Google Scholar 

  4. Hase T, Summers PT, Cohen WH (1989) A comparative study of entry modes into C6/36 cells by Semliki Forest and Japanese encephalitis viruses. Arch Virol 108: 101–114

    Google Scholar 

  5. Helenius A, Kartenbeck J, Simons K, Fries E (1980) On the entry of Semliki Forest virus into BHK-21 cells. J Cell Biol 84: 404–420

    Google Scholar 

  6. Helenius A, Marsh M, White J (1982) Inhibition of Semliki Forest virus penetration by lysosomotropic weak base. J Gen Virol 58: 47–61

    Google Scholar 

  7. Helenius A (1984) Semliki Forest virus penetration from endosomes. Biol Cell 51: 181–186

    Google Scholar 

  8. Igarashi A (1987) Isolation of a Singh's Aedes albopictus cell clone sensitive to Dengue and Chikungunya viruses. J Gen Virol 40: 531–544

    Google Scholar 

  9. Kielian MC, Helenius A (1985) pH-induced alterations in the fusogenic spike protein of Semliki Forest virus. J Cell Biol 101: 2284–2291

    Google Scholar 

  10. Lambert N (1989) Isolation of microsomes. In: Harris ELV, Angal S (eds) Protein purification methods: a practical approach, III. Series. IRL Press, Oxford, pp 101–108

    Google Scholar 

  11. Lanzrein M, Weingart R, Kempf C (1993) pH-dependent pore formation in Semliki Forest virus-infected Aedes albopictus cells. Virology 193: 296–302

    Google Scholar 

  12. Lanzrein M, Schlegel A, Kempf C (1994) Entry and uncoating of enveloped viruses. Biochem J 302: 313–320

    Google Scholar 

  13. Lowry OH, Rosebrough NJ, Farr AL, Randall RJ (1951) protein determination with the folin reagent. J Biol Chem 193: 265–275

    Google Scholar 

  14. Marsh M, Bolzau E, helenius A (1983) Penetration of Semliki Forest virus from acidic prelysosomal vacuoles. Cell 32: 931–940

    Google Scholar 

  15. Mauracher CA, Gillam S, Shukin R, Tingle AJ (1991) pH-dependent solubility shift of rubella virus capsid protein. Virology 181: 773–777

    Google Scholar 

  16. Owen KE, Kuhn RJ (1996) Identification of a region in the Sindbis virus nucleocapsid protein that is involved in specificity of RNA encapsidation. J Virol 70: 2757–2763

    Google Scholar 

  17. Pertoft H, Laurent TC, Seljelid R, Akerström G, Kagedal L, Hirstenstein M (1979) The use of density gradients of Percoll for the separation of biological particles. In: Peeters H (ed) Separation of cells and subcellular elements. Pergamon Press Ltd., Oxford, pp 67–72

    Google Scholar 

  18. Poole B, Ohkuma S (1981) Effect of week bases on the intralysosomal pH in mouse peritoneal macrophages. J Cell Biol 90: 665–669

    Google Scholar 

  19. Randolph VB, Stollar V (1990) Low pH-induced cell fusion in flavivirus infected Aedes albopictus cell cultures. J Gen Virol 71: 1845–1850

    Google Scholar 

  20. Rickwood D (1983) Iodinated density gradient media: a practical approach. IRL Press, Oxford

    Google Scholar 

  21. Schägger H, von Jagow G (1987) Tricine-sodium dodecyl sulfate-polyacrylamide gel electrophoresis for the separation of proteins in the range from 1 to 100 kDa. Anal Biochem 166: 368–379

    Google Scholar 

  22. Schlegel A, Omar A, Jentsch P, Morell A, Kempf C (1991) Semliki Forest virus envelope proteins function as proton channels. Biosci Rep 11: 243–255

    Google Scholar 

  23. Schlegel A, Schaller J, Jentsch P, Kempf C (1993) Semliki Forest virus core protein fragmentation: its possible role in nucleocapsid disassembly. Biosci Rep 13: 333–347

    Google Scholar 

  24. Schmid S, Fuchs R, Male P, Mellman (1988) Two distinct populations of endosomes involved in membrane recycling and transport to lysosomes. Cell 52: 73–83

    Google Scholar 

  25. Schmid S, Fuchs R, Kielian M, Helenius A, Mellman I (1989) Acidification of endosome subpopulations in wild-type Chinese hamster ovary cells and temperature-sensitive acidification-defective mutants. J Cell Biol 108: 1291–1300

    Google Scholar 

  26. Singh I, Helenius A (1992) Role of ribosomes in Semliki Forest virus nucleocapsid uncoating. J Virol 66: 7049–7058

    Google Scholar 

  27. Söderlund H, von Bonsdorff CH, Ulmanen I (1979) Comparison of the structural properties of Sindbis and Semliki Forest virus nucleocapsids. J Gen Virol 45: 15–26

    Google Scholar 

  28. Strong RK, Harrison SC (1990) Proteolytic dissection of Sindbis virus core protein. J Virol 64: 3992–3994

    Google Scholar 

  29. Stubbs MJ, Miller A, Sizer PJH, Stephenson JR, Crooks AJ (1991) X-ray solution scattering of Sindbis virus: changes in conformation induced at low pH. J Mol Biol 221: 39–42

    Google Scholar 

  30. Ulmanen I, Soderlund H, Kääriäinen L (1979) Role of protein synthesis in the assembly of Semliki Forest virus nucleocapsid. Virology 99: 265–276

    Google Scholar 

  31. Wengler G, Wengler G (1984) Identification of a transfer of viral core protein to cellular ribosomes during the early stages of alphavirus infection. Virology 134: 435

    Google Scholar 

  32. Wengler G (1987) The mode of assembly of alphavirus cores implies a mechanism for the disassembly of the cores in the early stages of infection. Arch Virol 94: 1–14

    Google Scholar 

  33. Wengler G (1990) Structure and synthesis of the core protein: role in regulation of assembly and disassembly of alphavirus and flavivirus cores. In: Brinton MA, Heinz FX (ed) New aspects of positive-strand RNA viruses. American Society for Microbiology, Washington, pp 227–236

    Google Scholar 

  34. Wengler G, Würkner D, Wengler G (1992) Identification of a sequence element in the alphavirus core protein which mediates interaction of cores with ribosomes and the disassembly of cores. Virology 191: 880–888

    Google Scholar 

  35. Young JD-E, Young GPH, Cohn ZA, Lenard J (1983) Interaction of enveloped viruses with planar bilayer membranes: observations on Sendai, influenza, vesicular stomatitis, and Semliki Forest viruses. Virology 128: 186–194

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and permissions

About this article

Cite this article

Mrkic, B., Kempf, C. The fragmentation of incoming Semliki Forest virus nucleocapsids in mosquito (Aedes Albopictus) cells might be coupled to virion uncoating. Archives of Virology 141, 1805–1821 (1996). https://doi.org/10.1007/BF01718196

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF01718196

Keywords

Navigation