Protein Kinase R-dependent Regulation of Interleukin-10 in Response to Double-stranded RNA*
- Arindam Chakrabarti‡1,
- Anthony J. Sadler§1,
- Niladri Kar‡¶,
- Howard A. Young∥,
- Robert H. Silverman‡ and
- Bryan R. G. Williams§2
- Departments of ‡Cancer Biology and ¶Molecular Cardiology, Lerner Research Institute, The Cleveland Clinic, Cleveland, Ohio 44195, the §Monash Institute of Medical Research, Monash University, Clayton, Victoria 3168, Australia, and the ∥Laboratory of Experimental Immunology, NCI-Frederick, National Institutes of Health, Frederick, Maryland 21702
- 2 To whom correspondence should be addressed: Monash Institute of Medical Research, Monash Medical Centre, 246 Clayton Rd, Clayton, Victoria 3168, Australia. Tel.: 61-3-9594-7166; Fax: 61-3-9594-7167; E-mail: bryan.williams{at}med.monash.edu.au.
Abstract
The double-stranded RNA-activated protein kinase R (PKR) is an important component of antiviral defense. PKR participates in different signaling pathways in response to various stimuli to regulate translation via phosphorylation of the eukaryotic initiation factor 2α, and transcription via activating NF-κB and IRF-1, to induce pro-inflammatory cytokines. Here we show PKR regulates interleukin-10 induction in response to double-stranded RNA, bacterial lipopolysaccaride, and Sendai virus infection. Using chemical inhibitors, dominant negative constructs, and genetic knockouts, we demonstrate that the PKR-mediated interleukin-10 induction engages JNK and NF-κB. Together, our data demonstrate the role of PKR in regulating an anti-inflammatory cytokine. The findings have significance in antiviral as well as broader innate immune responses.
Footnotes
-
↵3 The abbreviations used are: PKR, protein kinase R; IFN, interferon; dsRNA, double-stranded RNA; IL, interleukin; TNFα, tumor necrosis factor α; LPS, lipopolysaccaride; RNAi, RNA interference; wt, wild-type; pkr-ko, pkr knockout; SM, spleen-derived macrophages; IκBα-SR, IκBα super-repressor; BMM, bone marrow-derived macrophages; PBS, phosphate-buffered saline; ChIP, chromatin immunoprecipitation; PI, propidium iodide; TLR, toll-like receptor; GFP, green fluorescent protein; FACS, fluorescent-activated cell sorting; FCS, fetal calf serum; EMSA, electrophoretic mobility shift assay; ELISA, enzyme-linked immunosorbent assay; JNK, c-Jun N-terminal kinase.
-
↵* This work was supported, in whole or in part, by National Institutes of Health Grants R01 AI034039 and P01 CA062220. The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked “advertisement” in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.
-
↵
The on-line version of this article (available at http://www.jbc.org) contains supplemental Figs. S1–S4.
-
↵1 Both authors contributed equally to this work.
-
- Received June 23, 2008.
- Revision received July 7, 2008.
- The American Society for Biochemistry and Molecular Biology, Inc.
