Inhibition of the Interferon- Inducible Protein Kinase PKR by HCV E2 Protein
10.1126/science.285.5424.107
Crossref journal-article
American Association for the Advancement of Science (AAAS)
Science (221)
Abstract

Most isolates of hepatitis C virus (HCV) infections are resistant to interferon, the only available therapy, but the mechanism underlying this resistance has not been defined. Here it is shown that the HCV envelope protein E2 contains a sequence identical with phosphorylation sites of the interferon-inducible protein kinase PKR and the translation initiation factor eIF2α, a target of PKR. E2 inhibited the kinase activity of PKR and blocked its inhibitory effect on protein synthesis and cell growth. This interaction of E2 and PKR may be one mechanism by which HCV circumvents the antiviral effect of interferon.

Bibliography

Taylor, D. R., Shi, S. T., Romano, P. R., Barber, G. N., & Lai, M. M. C. (1999). Inhibition of the Interferon- Inducible Protein Kinase PKR by HCV E2 Protein. Science, 285(5424), 107–110.

Authors 5
  1. Deborah R. Taylor (first)
  2. Stephanie T. Shi (additional)
  3. Patrick R. Romano (additional)
  4. Glen N. Barber (additional)
  5. Michael M. C. Lai (additional)
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  10. BL21(DE3) bacterial cells were transformed with plasmids expressing His-tagged wild-type and mutant (K296R) PKR (pET-14b; Novagen) or green fluorescent protein (pRSET-GFP; Invitrogen) and were induced for 3 hours in the presence of 0.5 M isopropyl-β- d -thiogalactopyranoside. Proteins were extracted by sonication and equal amounts of His-tagged proteins were incubated with nickel nitrilotriacetic acid agarose (Qiagen) for 18 hours at 4°C. The beads were washed with phosphate-buffered saline (PBS) containing 0.02 M imidazole (Amresco) and 0.3% NP-40 and were then incubated for 2 hours at 4°C in binding buffer [0.04 M Hepes-K (pH 7.5) 0.1 M KCl 0.1% NP-40 0.02 M β-mercaptoethanol]. The beads were washed seven times with binding buffer plus 0.02 M imidazole and 0.85% NP-40. Bound radiolabeled proteins were eluted with SDS sample buffer and boiled before SDS-PAGE analysis.
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  28. We thank M. B. Mathews for polyclonal antiserum to PKR; B. Thimmapaya for dl331 adenovirus; T.-Y. Hsieh for hnRNPK-pcDNA3; and P. Koetters J.-W. Oh and members of the Lai laboratory for helpful discussions. Confocal microscopy was performed at the cell biology core laboratory of University of Southern California Liver Center. Supported by a NIH grant (AI 40038) and by a postdoctoral fellowship to D.R.T. from the NIH.
Dates
Type When
Created 23 years ago (July 27, 2002, 5:42 a.m.)
Deposited 1 year, 7 months ago (Jan. 13, 2024, 4 a.m.)
Indexed 3 weeks, 5 days ago (July 30, 2025, 10:43 a.m.)
Issued 26 years, 1 month ago (July 2, 1999)
Published 26 years, 1 month ago (July 2, 1999)
Published Print 26 years, 1 month ago (July 2, 1999)
Funders 0

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@article{Taylor_1999, title={Inhibition of the Interferon- Inducible Protein Kinase PKR by HCV E2 Protein}, volume={285}, ISSN={1095-9203}, url={http://dx.doi.org/10.1126/science.285.5424.107}, DOI={10.1126/science.285.5424.107}, number={5424}, journal={Science}, publisher={American Association for the Advancement of Science (AAAS)}, author={Taylor, Deborah R. and Shi, Stephanie T. and Romano, Patrick R. and Barber, Glen N. and Lai, Michael M. C.}, year={1999}, month=jul, pages={107–110} }