1887

Abstract

It has been demonstrated that both uncleaved, enzymitically inactive NS2/3 and cleaved NS2 proteins are rapidly degraded upon expression in cells, phenomena described to be blocked by the addition of proteasome inhibitors. As this degradation and its regulation potentially constitute an important strategy of the hepatitis C virus (HCV) to regulate the levels of its non-structural proteins, we further investigated the turnover of these proteins in relevant RNA replication systems. A lysine-mutagenesis approach was used in an effort to prevent protein degradation and determine any effect on various steps of the viral replication cycle. We show that, while NS2-lysine mutagenesis of protease-inactive NS2/3 results in a partial stabilization of this protein, the increased NS2/3 levels do not rescue the inability of NS2/3 protease inactive replicons to replicate, suggesting that uncleaved NS2/3 is unable to functionally replace NS3 in RNA replication. Furthermore, we show that the cleaved NS2 protein is rapidly degraded in several transient and stable RNA replicon systems and that NS2 from several different genotypes also has a short half-life, highlighting the potential importance of the regulation of NS2 levels for the viral life cycle. However, in contrast to uncleaved NS2/3, neither ubiquitin nor proteasomal degradation appear to be significantly involved in NS2 degradation. Finally, although NS2 lysine-to-arginine mutagenesis does not affect this protein's levels in a JFH-1 cell culture infection system, several of these residues are identified to be involved in virion assembly, further substantiating the importance of regions of this protein for production of infectious virus.

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2009-05-01
2024-04-18
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References

  1. Agapov E. V., Murray C. L., Frolov I., Qu L., Myers T. M., Rice C. M. 2004; Uncleaved NS2–3 is required for production of infectious bovine viral diarrhea virus. J Virol 78:2414–2425 [CrossRef]
    [Google Scholar]
  2. Alvarez-Castelao B., Castano J. G. 2005; Mechanism of direct degradation of I κ B α by 20S proteasome. FEBS Lett 579:4797–4802 [CrossRef]
    [Google Scholar]
  3. Binder M., Kochs G., Bartenschlager R., Lohmann V. 2007; Hepatitis C virus escape from the interferon regulatory factor 3 pathway by a passive and active evasion strategy. Hepatology 46:1365–1374 [CrossRef]
    [Google Scholar]
  4. Choo Q. L., Richman K. H., Han J. H., Berger K., Lee C., Dong C., Gallegos C., Coit D., Medina-Selby R. other authors 1991; Genetic organization and diversity of the hepatitis C virus. Proc Natl Acad Sci U S A 88:2451–2455 [CrossRef]
    [Google Scholar]
  5. Franck N., Le Seyec J., Guguen-Guillouzo C., Erdtmann L. 2005; Hepatitis C virus NS2 protein is phosphorylated by the protein kinase CK2 and targeted for degradation to the proteasome. J Virol 79:2700–2708 [CrossRef]
    [Google Scholar]
  6. Gao L., Tu H., Shi S. T., Lee K.-J., Asanaka M., Hwang S. B., Lai M. M. C. 2003; Interaction with a ubiquitin-like protein enhances the ubiquitination and degradation of hepatitis C virus RNA-dependent RNA polymerase. J Virol 77:4149–4159 [CrossRef]
    [Google Scholar]
  7. Gastaminza P., Kapadia S. B., Chisari F. V. 2006; Differential biophysical properties of infectious intracellular and secreted hepatitis C virus particles. J Virol 80:11074–11081 [CrossRef]
    [Google Scholar]
  8. Grakoui A., McCourt D. W., Wychowski C., Feinstone S. M., Rice C. M. 1993; A second hepatitis C virus-encoded proteinase. Proc Natl Acad Sci U S A 90:10583–10587 [CrossRef]
    [Google Scholar]
  9. Guex N., Peitsch M. C. 1997; SWISS-MODEL and the Swiss-PdbViewer: an environment for comparative protein modeling. Electrophoresis 18:2714–2723 [CrossRef]
    [Google Scholar]
  10. Hershko A., Ciechanover A. 1998; The ubiquitin system. Annu Rev Biochem 67:425–479 [CrossRef]
    [Google Scholar]
  11. Hijikata M., Mizushima H., Akagi T., Mori S., Kakiuchi N., Kato N., Tanaka T., Kimura K., Shimotohno K. 1993a; Two distinct proteinase activities required for the processing of a putative nonstructural precursor protein of hepatitis C virus. J Virol 67:4665–4675
    [Google Scholar]
  12. Hijikata M., Mizushima H., Tanji Y., Komoda Y., Hirowatari Y., Akagi T., Kato N., Kimura K., Shimotohno K. 1993b; Proteolytic processing and membrane association of putative nonstructural proteins of hepatitis C virus. Proc Natl Acad Sci U S A 90:10773–10777 [CrossRef]
    [Google Scholar]
  13. Jirasko V., Montserret R., Appel N., Janvier A., Eustachi L., Brohm C., Steinmann E., Pietschmann T., Penin F., Bartenschlager R. 2008; Structural and functional characterization of non-structural protein 2 for its role in hepatitis C virus assembly. J Biol Chem 283:28546–28562 [CrossRef]
    [Google Scholar]
  14. Jones C. T., Murray C. L., Eastman D. K., Tassello J., Rice C. M. 2007; Hepatitis C virus p7 and NS2 proteins are essential for production of infectious virus. J Virol 81:8374–8383 [CrossRef]
    [Google Scholar]
  15. Kim D. W., Gwack Y., Han J. H., Choe J. 1995; C-terminal domain of the hepatitis C virus NS3 protein contains an RNA helicase activity. Biochem Biophys Res Commun 215:160–166 [CrossRef]
    [Google Scholar]
  16. Kolykhalov A. A., Mihalik K., Feinstone S. M., Rice C. M. 2000; Hepatitis C virus-encoded enzymatic activities and conserved RNA elements in the 3′ nontranslated region are essential for virus replication in vivo . J Virol 74:2046–2051 [CrossRef]
    [Google Scholar]
  17. Koutsoudakis G., Herrmann E., Kallis S., Bartenschlager R., Pietschmann T. 2007; The level of CD81 cell surface expression is a key determinant for productive entry of hepatitis C virus into host cells. J Virol 81:588–598 [CrossRef]
    [Google Scholar]
  18. Lackner T., Muller A., Pankraz A., Becher P., Thiel H. J., Gorbalenya A. E., Tautz N. 2004; Temporal modulation of an autoprotease is crucial for replication and pathogenicity of an RNA virus. J Virol 78:10765–10775 [CrossRef]
    [Google Scholar]
  19. Lohmann V., Korner F., Dobierzewska A., Bartenschlager R. 2001; Mutations in hepatitis C virus RNAs conferring cell culture adaptation. J Virol 75:1437–1449 [CrossRef]
    [Google Scholar]
  20. Lorenz I. C., Marcotrigiano J., Dentzer T. G., Rice C. M. 2006; Structure of the catalytic domain of the hepatitis C virus NS2–3 protease. Nature 442:831–835 [CrossRef]
    [Google Scholar]
  21. Miller R. H., Purcell R. H. 1990; Hepatitis C virus shares amino acid sequence similarity with pestiviruses and flaviviruses as well as members of two plant virus supergroups. Proc Natl Acad Sci U S A 87:2057–2061 [CrossRef]
    [Google Scholar]
  22. Mousnier A., Kubat N., Massias-Simon A., Segeral E., Rain J.-C., Benarous R., Emiliani S., Dargemont C. 2007; von Hippel–Lindau binding protein 1-mediated degradation of integrase affects HIV-1 gene expression at a postintegration step. Proc Natl Acad Sci U S A 104:13615–13620 [CrossRef]
    [Google Scholar]
  23. Murakami Y., Matsufuji S., Kameji T., Hayashi S., Igarashi K., Tamura T., Tanaka K., Ichihara A. 1992; Ornithine decarboxylase is degraded by the 26S proteasome without ubiquitination. Nature 360:597–599 [CrossRef]
    [Google Scholar]
  24. Murray C. L., Jones C. T., Tassello J., Rice C. M. 2007; Alanine scanning of the hepatitis C virus core protein reveals numerous residues essential for production of infectious virus. J Virol 81:10220–10231 [CrossRef]
    [Google Scholar]
  25. Pavio N., Taylor D. R., Lai M. M. C. 2002; Detection of a novel unglycosylated form of hepatitis C virus E2 envelope protein that is located in the cytosol and interacts with PKR. J Virol 76:1265–1272 [CrossRef]
    [Google Scholar]
  26. Pietschmann T., Lohmann V., Rutter G., Kurpanek K., Bartenschlager R. 2001; Characterization of cell lines carrying self-replicating hepatitis C virus RNAs. J Virol 75:1252–1264 [CrossRef]
    [Google Scholar]
  27. Pietschmann T., Lohmann V., Kaul A., Krieger N., Rinck G., Rutter G., Strand D., Bartenschlager R. 2002; Persistent and transient replication of full-length hepatitis C virus genomes in cell culture. J Virol 76:4008–4021 [CrossRef]
    [Google Scholar]
  28. Pietschmann T., Kaul A., Koutsoudakis G., Shavinskaya A., Kallis S., Steinmann E., Abid K., Negro F., Dreux M. other authors 2006; Construction and characterization of infectious intragenotypic and intergenotypic hepatitis C virus chimeras. Proc Natl Acad Sci U S A 103:7408–7413 [CrossRef]
    [Google Scholar]
  29. Schlax P. E., Zhang J., Lewis E., Planchart A., Lawson T. G. 2007; Degradation of the encephalomyocarditis virus and hepatitis A virus 3C proteases by the ubiquitin/26S proteasome system in vivo. Virology 360:350–363 [CrossRef]
    [Google Scholar]
  30. Shavinskaya A., Boulant S., Penin F., McLauchlan J., Bartenschlager R. 2007; The lipid droplet binding domain of hepatitis C virus core protein is a major determinant for efficient virus assembly. J Biol Chem 282:37158–37169 [CrossRef]
    [Google Scholar]
  31. Shirakura M., Murakami K., Ichimura T., Suzuki R., Shimoji T., Fukuda K., Abe K., Sato S., Fukasawa M. other authors 2007; E6AP ubiquitin ligase mediates ubiquitylation and degradation of hepatitis C virus core protein. J Virol 81:1174–1185 [CrossRef]
    [Google Scholar]
  32. Suzuki R., Tamura K., Li J., Ishii K., Matsuura Y., Miyamura T., Suzuki T. 2001; Ubiquitin-mediated degradation of hepatitis C virus core protein is regulated by processing at its carboxyl terminus. Virology 280:301–309 [CrossRef]
    [Google Scholar]
  33. Tellinghuisen T. L., Foss K. L., Treadaway J. 2008; Regulation of hepatitis C virion production via phosphorylation of the NS5A protein. PLoS Pathog 4:e1000032 [CrossRef]
    [Google Scholar]
  34. Wakita T., Pietschmann T., Kato T., Date T., Miyamoto M., Zhao Z., Murthy K., Habermann A., Krausslich H. G. other authors 2005; Production of infectious hepatitis C virus in tissue culture from a cloned viral genome. Nat Med 11:791–796 [CrossRef]
    [Google Scholar]
  35. Wang W., Nacusi L., Sheaff R. J., Liu X. 2005; Ubiquitination of p21Cip1/WAF1 by SCFSkp2: substrate requirement and ubiquitination site selection. Biochemistry 44:14553–14564 [CrossRef]
    [Google Scholar]
  36. Welbourn S., Green R., Gamache I., Dandache S., Lohmann V., Bartenschlager R., Meerovitch K., Pause A. 2005; Hepatitis C virus NS2/3 processing is required for NS3 stability and viral RNA replication. J Biol Chem 280:29604–29611 [CrossRef]
    [Google Scholar]
  37. Yi M., Ma Y., Yates J., Lemon S. M. 2007; Compensatory mutations in E1, p7, NS2, and NS3 enhance yields of cell culture-infectious intergenotypic chimeric hepatitis C virus. J Virol 81:629–638 [CrossRef]
    [Google Scholar]
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