Premium
Serine/threonine kinase PKR: A sentinel kinase that discriminates a signaling pathway mediated by TLR4 from those mediated by TLR3 and TLR9
Author(s) -
Asakura Yusuke,
Fujiwara Yoshihiro,
Kato Naoko,
Sato Yuko,
Komatsu Toru
Publication year - 2007
Publication title -
american journal of hematology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.456
H-Index - 105
eISSN - 1096-8652
pISSN - 0361-8609
DOI - 10.1002/ajh.20817
Subject(s) - tlr3 , signal transducing adaptor protein , tlr9 , receptor , innate immune system , signal transduction , tlr4 , microbiology and biotechnology , biology , kinase , pattern recognition receptor , protein kinase r , tlr2 , phosphorylation , toll like receptor , protein kinase a , mitogen activated protein kinase kinase , biochemistry , gene , gene expression , dna methylation
Cells of the innate immune system discriminate between “noninfectious self” and “infectious nonself” via pattern recognition receptors known as Toll‐like receptors (TLRs). Though TLRs and the related interleukin 1 receptors share considerable homology in their cytoplasmic domains and adaptor molecules, signaling cascades may substantially differ from one another depending on the adaptor proteins recruited. Here we show that ectopic overexpression of catalytically inactive dominant‐negative PKR expression system suppressed NF‐ κ B activation mediated by TLR3, TLR9, TNF receptor 1 and 2 (TNF‐R 1/2), but not by TLR4. Physiological relevance of the observations described here are discussed. Am. J. Hematol 2007. © 2006 Wiley‐Liss, Inc.