Abstract
The signaling mechanisms responsible for the induced expression of interferon (IFN) genes by viral infection or double-stranded RNA (dsRNA) are not well understood. Here we investigate the role of the interferon-induced dsRNA-dependent protein kinase PKR in the regulation of IFN induction. Biological activities attributed to PKR include regulating protein synthesis, mediating IFN actions, and functioning as a possible tumor suppressor. Since binding of dsRNA is required for its activation, PKR has been considered as a candidate signal transducer for regulating IFN expression. To examine this role of PKR, loss-of-function phenotypes in stable transformants of promonocytic U-937 cells were achieved by two different strategies, overexpression of an antisense PKR transcript or a dominant negative PKR mutant gene. Both types of PKR-deficient cells were more permissive for viral replication than the control U-937 cells. As the result of PKR loss, they also showed impaired induction of IFN-alpha and IFN-beta genes in response to several inducers--specifically, encephalomyocarditis virus, lipopolysaccharide, and phorbol 12-myristate 13-acetate. Interestingly, while IFN-alpha induction by dsRNA was impaired in PKR-deficient cells, IFN-beta induction remained intact. Loss of PKR function also resulted in decreased antiviral activity as elicited by IFN-alpha and, to a greater extent, by IFN-gamma. These results implicate PKR in the regulation of several antiviral activities.
Full text
PDF![8841](https://cdn.ncbi.nlm.nih.gov/pmc/blobs/54cb/41063/3af9cab1406c/pnas01497-0318.png)
![8842](https://cdn.ncbi.nlm.nih.gov/pmc/blobs/54cb/41063/bc10caf8eb25/pnas01497-0319.png)
![8843](https://cdn.ncbi.nlm.nih.gov/pmc/blobs/54cb/41063/eb3c1d03e467/pnas01497-0320.png)
![8844](https://cdn.ncbi.nlm.nih.gov/pmc/blobs/54cb/41063/38264435f6d2/pnas01497-0321.png)
![8845](https://cdn.ncbi.nlm.nih.gov/pmc/blobs/54cb/41063/41ef506f2e89/pnas01497-0322.png)
Images in this article
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Arnheiter H., Skuntz S., Noteborn M., Chang S., Meier E. Transgenic mice with intracellular immunity to influenza virus. Cell. 1990 Jul 13;62(1):51–61. doi: 10.1016/0092-8674(90)90239-b. [DOI] [PubMed] [Google Scholar]
- Chebath J., Benech P., Revel M., Vigneron M. Constitutive expression of (2'-5') oligo A synthetase confers resistance to picornavirus infection. Nature. 1987 Dec 10;330(6148):587–588. doi: 10.1038/330587a0. [DOI] [PubMed] [Google Scholar]
- D'Addario M., Roulston A., Wainberg M. A., Hiscott J. Coordinate enhancement of cytokine gene expression in human immunodeficiency virus type 1-infected promonocytic cells. J Virol. 1990 Dec;64(12):6080–6089. doi: 10.1128/jvi.64.12.6080-6089.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Daly C., Reich N. C. Double-stranded RNA activates novel factors that bind to the interferon-stimulated response element. Mol Cell Biol. 1993 Jun;13(6):3756–3764. doi: 10.1128/mcb.13.6.3756. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Darnell J. E., Jr, Kerr I. M., Stark G. R. Jak-STAT pathways and transcriptional activation in response to IFNs and other extracellular signaling proteins. Science. 1994 Jun 3;264(5164):1415–1421. doi: 10.1126/science.8197455. [DOI] [PubMed] [Google Scholar]
- Du W., Thanos D., Maniatis T. Mechanisms of transcriptional synergism between distinct virus-inducible enhancer elements. Cell. 1993 Sep 10;74(5):887–898. doi: 10.1016/0092-8674(93)90468-6. [DOI] [PubMed] [Google Scholar]
- Farrar M. A., Schreiber R. D. The molecular cell biology of interferon-gamma and its receptor. Annu Rev Immunol. 1993;11:571–611. doi: 10.1146/annurev.iy.11.040193.003035. [DOI] [PubMed] [Google Scholar]
- Galabru J., Hovanessian A. Autophosphorylation of the protein kinase dependent on double-stranded RNA. J Biol Chem. 1987 Nov 15;262(32):15538–15544. [PubMed] [Google Scholar]
- Gutterman J. U. Cytokine therapeutics: lessons from interferon alpha. Proc Natl Acad Sci U S A. 1994 Feb 15;91(4):1198–1205. doi: 10.1073/pnas.91.4.1198. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hassel B. A., Zhou A., Sotomayor C., Maran A., Silverman R. H. A dominant negative mutant of 2-5A-dependent RNase suppresses antiproliferative and antiviral effects of interferon. EMBO J. 1993 Aug;12(8):3297–3304. doi: 10.1002/j.1460-2075.1993.tb05999.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hershey J. W. Translational control in mammalian cells. Annu Rev Biochem. 1991;60:717–755. doi: 10.1146/annurev.bi.60.070191.003441. [DOI] [PubMed] [Google Scholar]
- Hovanessian A. G., Galabru J. The double-stranded RNA-dependent protein kinase is also activated by heparin. Eur J Biochem. 1987 Sep 15;167(3):467–473. doi: 10.1111/j.1432-1033.1987.tb13360.x. [DOI] [PubMed] [Google Scholar]
- Ito T., Jagus R., May W. S. Interleukin 3 stimulates protein synthesis by regulating double-stranded RNA-dependent protein kinase. Proc Natl Acad Sci U S A. 1994 Aug 2;91(16):7455–7459. doi: 10.1073/pnas.91.16.7455. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kerr I. M., Stark G. R. The antiviral effects of the interferons and their inhibition. J Interferon Res. 1992 Aug;12(4):237–240. doi: 10.1089/jir.1992.12.237. [DOI] [PubMed] [Google Scholar]
- Kimura T., Nakayama K., Penninger J., Kitagawa M., Harada H., Matsuyama T., Tanaka N., Kamijo R., Vilcek J., Mak T. W. Involvement of the IRF-1 transcription factor in antiviral responses to interferons. Science. 1994 Jun 24;264(5167):1921–1924. doi: 10.1126/science.8009222. [DOI] [PubMed] [Google Scholar]
- Koromilas A. E., Roy S., Barber G. N., Katze M. G., Sonenberg N. Malignant transformation by a mutant of the IFN-inducible dsRNA-dependent protein kinase. Science. 1992 Sep 18;257(5077):1685–1689. doi: 10.1126/science.1382315. [DOI] [PubMed] [Google Scholar]
- Kumar A., Haque J., Lacoste J., Hiscott J., Williams B. R. Double-stranded RNA-dependent protein kinase activates transcription factor NF-kappa B by phosphorylating I kappa B. Proc Natl Acad Sci U S A. 1994 Jul 5;91(14):6288–6292. doi: 10.1073/pnas.91.14.6288. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lau A. S., Der S. D., Read S. E., Williams B. R. Regulation of tumor necrosis factor receptor expression by acid-labile interferon-alpha from AIDS sera. AIDS Res Hum Retroviruses. 1991 Jun;7(6):545–552. doi: 10.1089/aid.1991.7.545. [DOI] [PubMed] [Google Scholar]
- Lengyel P. Double-stranded RNA and interferon action. J Interferon Res. 1987 Oct;7(5):511–519. doi: 10.1089/jir.1987.7.511. [DOI] [PubMed] [Google Scholar]
- Maran A., Maitra R. K., Kumar A., Dong B., Xiao W., Li G., Williams B. R., Torrence P. F., Silverman R. H. Blockage of NF-kappa B signaling by selective ablation of an mRNA target by 2-5A antisense chimeras. Science. 1994 Aug 5;265(5173):789–792. doi: 10.1126/science.7914032. [DOI] [PubMed] [Google Scholar]
- Marcus P. I., Sekellick M. J. Interferon induction by viruses. XVI. 2-Aminopurine blocks selectively and reversibly an early stage in interferon induction. J Gen Virol. 1988 Jul;69(Pt 7):1637–1645. doi: 10.1099/0022-1317-69-7-1637. [DOI] [PubMed] [Google Scholar]
- Matsuyama T., Kimura T., Kitagawa M., Pfeffer K., Kawakami T., Watanabe N., Kündig T. M., Amakawa R., Kishihara K., Wakeham A. Targeted disruption of IRF-1 or IRF-2 results in abnormal type I IFN gene induction and aberrant lymphocyte development. Cell. 1993 Oct 8;75(1):83–97. [PubMed] [Google Scholar]
- Meurs E. F., Galabru J., Barber G. N., Katze M. G., Hovanessian A. G. Tumor suppressor function of the interferon-induced double-stranded RNA-activated protein kinase. Proc Natl Acad Sci U S A. 1993 Jan 1;90(1):232–236. doi: 10.1073/pnas.90.1.232. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Meurs E. F., Watanabe Y., Kadereit S., Barber G. N., Katze M. G., Chong K., Williams B. R., Hovanessian A. G. Constitutive expression of human double-stranded RNA-activated p68 kinase in murine cells mediates phosphorylation of eukaryotic initiation factor 2 and partial resistance to encephalomyocarditis virus growth. J Virol. 1992 Oct;66(10):5805–5814. doi: 10.1128/jvi.66.10.5805-5814.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Meurs E., Chong K., Galabru J., Thomas N. S., Kerr I. M., Williams B. R., Hovanessian A. G. Molecular cloning and characterization of the human double-stranded RNA-activated protein kinase induced by interferon. Cell. 1990 Jul 27;62(2):379–390. doi: 10.1016/0092-8674(90)90374-n. [DOI] [PubMed] [Google Scholar]
- Pestka S., Langer J. A., Zoon K. C., Samuel C. E. Interferons and their actions. Annu Rev Biochem. 1987;56:727–777. doi: 10.1146/annurev.bi.56.070187.003455. [DOI] [PubMed] [Google Scholar]
- Rosztoczy I., Pitha P. M. Priming does not change promoter sequence requirements for IFN induction or correlate with the expression of IFN regulatory factor-1. J Immunol. 1993 Aug 1;151(3):1303–1311. [PubMed] [Google Scholar]
- Sen G. C., Lengyel P. The interferon system. A bird's eye view of its biochemistry. J Biol Chem. 1992 Mar 15;267(8):5017–5020. [PubMed] [Google Scholar]
- St Johnston D., Brown N. H., Gall J. G., Jantsch M. A conserved double-stranded RNA-binding domain. Proc Natl Acad Sci U S A. 1992 Nov 15;89(22):10979–10983. doi: 10.1073/pnas.89.22.10979. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tanaka H., Samuel C. E. Mechanism of interferon action: structure of the mouse PKR gene encoding the interferon-inducible RNA-dependent protein kinase. Proc Natl Acad Sci U S A. 1994 Aug 16;91(17):7995–7999. doi: 10.1073/pnas.91.17.7995. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tanaka N., Taniguchi T. Cytokine gene regulation: regulatory cis-elements and DNA binding factors involved in the interferon system. Adv Immunol. 1992;52:263–281. doi: 10.1016/s0065-2776(08)60877-9. [DOI] [PubMed] [Google Scholar]
- Visvanathan K. V., Goodbourn S. Double-stranded RNA activates binding of NF-kappa B to an inducible element in the human beta-interferon promoter. EMBO J. 1989 Apr;8(4):1129–1138. doi: 10.1002/j.1460-2075.1989.tb03483.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Zinn K., Keller A., Whittemore L. A., Maniatis T. 2-Aminopurine selectively inhibits the induction of beta-interferon, c-fos, and c-myc gene expression. Science. 1988 Apr 8;240(4849):210–213. doi: 10.1126/science.3281258. [DOI] [PubMed] [Google Scholar]