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. 1986 Dec 1;5(12):3103–3109. doi: 10.1002/j.1460-2075.1986.tb04616.x

Kinetics of endosome acidification detected by mutant and wild-type Semliki Forest virus.

M C Kielian, M Marsh, A Helenius
PMCID: PMC1167299  PMID: 3816755

Abstract

The fusogenic properties of Semliki Forest virus (SFV) and its mutants were used to follow the kinetics of acidification during the endocytic uptake of virus by BHK-21 cells. It has previously been shown that the low pH of endocytic vacuoles triggers a conformational change in the SFV spike glycoprotein, activating membrane fusion and initiating virus infection. This conformational alteration was here shown to occur in endosomes and to follow the same time course as the intracellular fusion reaction, demonstrating that fusion occurs rapidly after virus exposure to endosome acidity. The kinetics of endosome acidification were monitored using wild type (wt) SFV and fus-1, an SFV mutant with a lower fusion pH threshold. The results presented here demonstrated that wt and mutant virus were internalized with a t1/2 of 10 min, and that endosomes were acidified to the wt threshold of pH 6.2 with a t1/2 of 15 min. In contrast, endosome pH reached the fus-1 threshold of 5.3 with a much longer t1/2 of 45 min. The subsequent degradation of SFV in lysosomes had a t1/2 of 90 min. It was found that after the initial uptake of virus from the plasma membrane, its transit through the endocytic pathway, exposure to endosome acidity and eventual delivery to lysosomes were markedly asynchronous.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Anderson R. G., Brown M. S., Beisiegel U., Goldstein J. L. Surface distribution and recycling of the low density lipoprotein receptor as visualized with antireceptor antibodies. J Cell Biol. 1982 Jun;93(3):523–531. doi: 10.1083/jcb.93.3.523. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Bergeron J. J., Cruz J., Khan M. N., Posner B. I. Uptake of insulin and other ligands into receptor-rich endocytic components of target cells: the endosomal apparatus. Annu Rev Physiol. 1985;47:383–403. doi: 10.1146/annurev.ph.47.030185.002123. [DOI] [PubMed] [Google Scholar]
  3. Besterman J. M., Airhart J. A., Woodworth R. C., Low R. B. Exocytosis of pinocytosed fluid in cultured cells: kinetic evidence for rapid turnover and compartmentation. J Cell Biol. 1981 Dec;91(3 Pt 1):716–727. doi: 10.1083/jcb.91.3.716. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Brown M. S., Anderson R. G., Goldstein J. L. Recycling receptors: the round-trip itinerary of migrant membrane proteins. Cell. 1983 Mar;32(3):663–667. doi: 10.1016/0092-8674(83)90052-1. [DOI] [PubMed] [Google Scholar]
  5. 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]
  6. Dimmock N. J. Review article initial stages in infection with animal viruses. J Gen Virol. 1982 Mar;59(Pt 1):1–22. doi: 10.1099/0022-1317-59-1-1. [DOI] [PubMed] [Google Scholar]
  7. Fries E., Helenius A. Binding of Semliki Forest virus and its spike glycoproteins to cells. Eur J Biochem. 1979 Jun;97(1):213–220. doi: 10.1111/j.1432-1033.1979.tb13105.x. [DOI] [PubMed] [Google Scholar]
  8. Geuze H. J., Slot J. W., Strous G. J., Lodish H. F., Schwartz A. L. Intracellular site of asialoglycoprotein receptor-ligand uncoupling: double-label immunoelectron microscopy during receptor-mediated endocytosis. Cell. 1983 Jan;32(1):277–287. doi: 10.1016/0092-8674(83)90518-4. [DOI] [PubMed] [Google Scholar]
  9. Geuze H. J., Slot J. W., Strous G. J., Peppard J., von Figura K., Hasilik A., Schwartz A. L. Intracellular receptor sorting during endocytosis: comparative immunoelectron microscopy of multiple receptors in rat liver. Cell. 1984 May;37(1):195–204. doi: 10.1016/0092-8674(84)90315-5. [DOI] [PubMed] [Google Scholar]
  10. Goldstein J. L., Anderson R. G., Brown M. S. Coated pits, coated vesicles, and receptor-mediated endocytosis. Nature. 1979 Jun 21;279(5715):679–685. doi: 10.1038/279679a0. [DOI] [PubMed] [Google Scholar]
  11. Hahon N., Cooke K. O. Primary virus-cell interactions in the immunofluorescence assay of Venezuelan equine encephalomyelitis virus. J Virol. 1967 Apr;1(2):317–326. doi: 10.1128/jvi.1.2.317-326.1967. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. 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]
  13. 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]
  14. Helenius A., Marsh M., White J. Inhibition of Semliki forest virus penetration by lysosomotropic weak bases. J Gen Virol. 1982 Jan;58(Pt 1):47–61. doi: 10.1099/0022-1317-58-1-47. [DOI] [PubMed] [Google Scholar]
  15. Helenius A. Semliki Forest virus penetration from endosomes: a morphological study. Biol Cell. 1984;51(2):181–185. doi: 10.1111/j.1768-322x.1984.tb00297.x. [DOI] [PubMed] [Google Scholar]
  16. Hopkins C. R. The importance of the endosome in intracellular traffic. Nature. 1983 Aug 25;304(5928):684–685. doi: 10.1038/304684a0. [DOI] [PubMed] [Google Scholar]
  17. Kielian M. C., Keränen S., Käriäinen L., Helenius A. Membrane fusion mutants of Semliki Forest virus. J Cell Biol. 1984 Jan;98(1):139–145. doi: 10.1083/jcb.98.1.139. [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. Lenard J., Miller D. K. Uncoating of enveloped viruses. Cell. 1982 Jan;28(1):5–6. doi: 10.1016/0092-8674(82)90368-3. [DOI] [PubMed] [Google Scholar]
  20. Marsh M., Bolzau E., Helenius A. Penetration of Semliki Forest virus from acidic prelysosomal vacuoles. Cell. 1983 Mar;32(3):931–940. doi: 10.1016/0092-8674(83)90078-8. [DOI] [PubMed] [Google Scholar]
  21. 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]
  22. Marsh M. The entry of enveloped viruses into cells by endocytosis. Biochem J. 1984 Feb 15;218(1):1–10. doi: 10.1042/bj2180001. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. 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]
  24. Maxfield F. R. Weak bases and ionophores rapidly and reversibly raise the pH of endocytic vesicles in cultured mouse fibroblasts. J Cell Biol. 1982 Nov;95(2 Pt 1):676–681. doi: 10.1083/jcb.95.2.676. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Mellman I., Fuchs R., Helenius A. Acidification of the endocytic and exocytic pathways. Annu Rev Biochem. 1986;55:663–700. doi: 10.1146/annurev.bi.55.070186.003311. [DOI] [PubMed] [Google Scholar]
  26. Merion M., Schlesinger P., Brooks R. M., Moehring J. M., Moehring T. J., Sly W. S. Defective acidification of endosomes in Chinese hamster ovary cell mutants "cross-resistant" to toxins and viruses. Proc Natl Acad Sci U S A. 1983 Sep;80(17):5315–5319. doi: 10.1073/pnas.80.17.5315. [DOI] [PMC free article] [PubMed] [Google Scholar]
  27. Mueller S. C., Hubbard A. L. Receptor-mediated endocytosis of asialoglycoproteins by rat hepatocytes: receptor-positive and receptor-negative endosomes. J Cell Biol. 1986 Mar;102(3):932–942. doi: 10.1083/jcb.102.3.932. [DOI] [PMC free article] [PubMed] [Google Scholar]
  28. Murphy R. F., Powers S., Cantor C. R. Endosome pH measured in single cells by dual fluorescence flow cytometry: rapid acidification of insulin to pH 6. J Cell Biol. 1984 May;98(5):1757–1762. doi: 10.1083/jcb.98.5.1757. [DOI] [PMC free article] [PubMed] [Google Scholar]
  29. Schwartz A. L., Fridovich S. E., Lodish H. F. Kinetics of internalization and recycling of the asialoglycoprotein receptor in a hepatoma cell line. J Biol Chem. 1982 Apr 25;257(8):4230–4237. [PubMed] [Google Scholar]
  30. Steinman R. M., Brodie S. E., Cohn Z. A. Membrane flow during pinocytosis. A stereologic analysis. J Cell Biol. 1976 Mar;68(3):665–687. doi: 10.1083/jcb.68.3.665. [DOI] [PMC free article] [PubMed] [Google Scholar]
  31. Steinman R. M., Mellman I. S., Muller W. A., Cohn Z. A. Endocytosis and the recycling of plasma membrane. J Cell Biol. 1983 Jan;96(1):1–27. doi: 10.1083/jcb.96.1.1. [DOI] [PMC free article] [PubMed] [Google Scholar]
  32. Tanasugarn L., McNeil P., Reynolds G. T., Taylor D. L. Microspectrofluorometry by digital image processing: measurement of cytoplasmic pH. J Cell Biol. 1984 Feb;98(2):717–724. doi: 10.1083/jcb.98.2.717. [DOI] [PMC free article] [PubMed] [Google Scholar]
  33. Tycko B., Maxfield F. R. Rapid acidification of endocytic vesicles containing alpha 2-macroglobulin. Cell. 1982 Mar;28(3):643–651. doi: 10.1016/0092-8674(82)90219-7. [DOI] [PubMed] [Google Scholar]
  34. Wall D. A., Hubbard A. L. Receptor-mediated endocytosis of asialoglycoproteins by rat liver hepatocytes: biochemical characterization of the endosomal compartments. J Cell Biol. 1985 Dec;101(6):2104–2112. doi: 10.1083/jcb.101.6.2104. [DOI] [PMC free article] [PubMed] [Google Scholar]
  35. Walter P., Jackson R. C., Marcus M. M., Lingappa V. R., Blobel G. Tryptic dissection and reconstitution of translocation activity for nascent presecretory proteins across microsomal membranes. Proc Natl Acad Sci U S A. 1979 Apr;76(4):1795–1799. doi: 10.1073/pnas.76.4.1795. [DOI] [PMC free article] [PubMed] [Google Scholar]
  36. 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]
  37. White J., Kielian M., Helenius A. Membrane fusion proteins of enveloped animal viruses. Q Rev Biophys. 1983 May;16(2):151–195. doi: 10.1017/s0033583500005072. [DOI] [PubMed] [Google Scholar]
  38. 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]
  39. Willingham M. C., Pastan I. The receptosome: an intermediate organelle of receptor mediated endocytosis in cultured fibroblasts. Cell. 1980 Aug;21(1):67–77. doi: 10.1016/0092-8674(80)90115-4. [DOI] [PubMed] [Google Scholar]
  40. Wolkoff A. W., Klausner R. D., Ashwell G., Harford J. Intracellular segregation of asialoglycoproteins and their receptor: a prelysosomal event subsequent to dissociation of the ligand-receptor complex. J Cell Biol. 1984 Feb;98(2):375–381. doi: 10.1083/jcb.98.2.375. [DOI] [PMC free article] [PubMed] [Google Scholar]
  41. Yamashiro D. J., Tycko B., Fluss S. R., Maxfield F. R. Segregation of transferrin to a mildly acidic (pH 6.5) para-Golgi compartment in the recycling pathway. Cell. 1984 Jul;37(3):789–800. doi: 10.1016/0092-8674(84)90414-8. [DOI] [PubMed] [Google Scholar]

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