title: PIKfyve regulates the endosomal localization of CpG oligodeoxynucleotides to elicit TLR9-dependent cellular responses.
abstract: TLR9 is a receptor for oligodeoxynucleotides that contain unmethylated CpG motifs (CpG). Because TLR9 resides in the endoplasmic reticulum during the quiescence state, CpG binding to TLR9 requires membrane trafficking, which includes the maturation of the CpG-containing endosome. In the present study, we examined the role of PIKfyve, a phosphatidylinositol 3-phosphate 5-kinase, in the regulation of TLR9 signaling. The PIKfyve inhibitor YM201636 inhibited co-localization of the CpG-containing endosome with LysoTracker, which stains acidic organelle, and with TLR9. YM201636 increased the co-localization of CpG with the early endosome marker EEA1 but decreased co-localization with the late endosome marker LAMP1. Similar results were obtained in Raw264.7 cells containing shRNA that targets PIKfyve. CpG-mediated phosphorylation but not lipopolysaccharide (LPS)-mediated phosphorylation of IKK, p38 MAPK, JNK and Stat3 was severely impaired by the loss of PIKfyve function. CpG-mediated expression of cytokine mRNA was also decreased in the absence of PIKfyve. These findings demonstrate a novel role of PIKfyve in TLR9 signaling.
authors.affiliation: Division of Molecular Medical Science, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima, Japan.
authors.forename: Kaoru
authors.initials: K
authors.lastname: Hazeki
authors.forename: Masami
authors.initials: M
authors.lastname: Uehara
authors.forename: Kiyomi
authors.initials: K
authors.lastname: Nigorikawa
authors.forename: Osamu
authors.initials: O
authors.lastname: Hazeki
mesh_terms: D000631:Aminopyridines / Q000494:pharmacology; D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D002460:Cell Line; D016207:Cytokines / Q000235:genetics / Q000378:metabolism; D011992:Endosomes / Q000378:metabolism*; D005260:Female; D005786:Gene Expression Regulation / Q000187:drug effects; D055785:Gene Knockdown Techniques; D006575:Heterocyclic Compounds, 3-Ring / Q000494:pharmacology; D017737:Macrophages, Peritoneal / Q000187:drug effects / Q000378:metabolism; D051379:Mice; D009838:Oligodeoxyribonucleotides / Q000378:metabolism*; D019869:Phosphatidylinositol 3-Kinases / Q000235:genetics / Q000378:metabolism*; D000081082:Phosphoinositide-3 Kinase Inhibitors; D011485:Protein Binding; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D051217:Toll-Like Receptor 9 / Q000378:metabolism*
chemical_list: D000631:Aminopyridines; D016207:Cytokines; D006575:Heterocyclic Compounds, 3-Ring; D009838:Oligodeoxyribonucleotides; D019869:Phosphatidylinositol 3-Kinases; D000081082:Phosphoinositide-3 Kinase Inhibitors; D012333:RNA, Messenger; D051217:Toll-Like Receptor 9; C540576:6-amino-N-(3-(4-(4-morpholinyl)pyrido(3',2'-4,5)furo(3,2-d)pyrimidin-2-yl)phenyl)-3-pyridinecarboxamide; C408982:CPG-oligonucleotide; C116930:Pikfyve protein, mouse
references.citation: EMBO J. 2006 Feb 22;25(4):683-92
references.pmid: 16467847
references.citation: J Exp Med. 2006 Aug 7;203(8):1999-2008
references.pmid: 16864658
references.citation: Biochem J. 2009 Sep 14;423(1):99-108
references.pmid: 19604150
references.citation: Nat Immunol. 2010 May;11(5):373-84
references.pmid: 20404851
references.citation: Biochim Biophys Acta. 2012 Aug;1821(8):1104-13
references.pmid: 22281700
references.citation: Biochem Biophys Res Commun. 2009 May 8;382(3):566-70
references.pmid: 19289105
references.citation: J Biol Chem. 2012 Feb 3;287(6):4323-34
references.pmid: 22170068
references.citation: Nat Immunol. 2008 Dec;9(12):1407-14
references.pmid: 18931679
references.citation: Rheumatology (Oxford). 2006 Jun;45(6):703-10
references.pmid: 16418198
references.citation: EMBO J. 2010 Apr 21;29(8):1331-47
references.pmid: 20300065
references.citation: J Biol Chem. 2005 Mar 4;280(9):8086-93
references.pmid: 15591070
references.citation: Cell Biol Int. 2008 Jun;32(6):591-604
references.pmid: 18304842
references.citation: J Immunol. 2006 May 15;176(10):5943-9
references.pmid: 16670302
references.citation: J Exp Med. 2002 Jul 15;196(2):269-74
references.pmid: 12119352
references.citation: EMBO Rep. 2008 Feb;9(2):164-70
references.pmid: 18188180
references.citation: Traffic. 2009 Jul;10(7):883-93
references.pmid: 19582903
references.citation: Semin Immunol. 2004 Feb;16(1):17-22
references.pmid: 14751759
references.citation: J Biol Chem. 2006 Nov 17;281(46):35585-92
references.pmid: 16990271
references.citation: Traffic. 2012 Jan;13(1):1-8
references.pmid: 21736686
references.citation: J Biol Chem. 2011 Apr 15;286(15):13404-13
references.pmid: 21349843
references.citation: J Cell Sci. 2006 Oct 1;119(Pt 19):3944-57
references.pmid: 16954148
references.citation: J Exp Med. 2009 Jun 8;206(6):1339-50
references.pmid: 19451267
references.citation: Cell. 2012 Aug 3;150(3):606-19
references.pmid: 22819539
references.citation: Cytokine. 2008 May;42(2):145-151
references.pmid: 18304834
references.citation: Curr Opin Immunol. 2010 Feb;22(1):20-7
references.pmid: 20060278
references.citation: Nature. 2005 Apr 21;434(7036):1035-40
references.pmid: 15815647
references.citation: Nat Immunol. 2008 Apr;9(4):361-8
references.pmid: 18297073
references.citation: Nat Immunol. 2004 Feb;5(2):190-8
references.pmid: 14716310
references.citation: J Cell Sci. 2006 Feb 15;119(Pt 4):605-14
references.pmid: 16467569
references.citation: Biochem J. 2005 Dec 15;392(Pt 3):607-14
references.pmid: 16091017
references.citation: J Cell Biol. 1988 Feb;106(2):269-77
references.pmid: 2892844