title: Silencing of Bruton's tyrosine kinase (Btk) using short interfering RNA duplexes (siRNA).
abstract: Tec family tyrosine kinases, Bruton's tyrosine kinase (Btk), Itk, Bmx, Tec, and Txk, are multi-domain proteins involved in hematopoietic signaling. Here, we demonstrate that human Btk protein can transiently be depleted using double-stranded short RNA interference (siRNA) oligonucleotides. Imaging and Western blotting analysis demonstrate that Btk expression is down regulated in heterologous systems as well as in hematopoietic lineages, following transfection or microinjection of Btk siRNA duplexes. The induction of histamine release, a pro-inflammatory mediator, in RBL-2H3 mast cells was reduced by 20-25% upon Btk down regulation. Similar, results were obtained when the Btk activity was inhibited using the kinase blocker LFM-A13. These results demonstrate a direct role of Btk for the efficient secretion of histamine in allergic responses.
authors.affiliation: Clinical Research Center (CRC), KFC-Novum, Karolinska Institutet, Huddinge University Hospital, SE-141 86, Huddinge, Sweden
authors.forename: Juhana E
authors.initials: JE
authors.lastname: Heinonen
authors.forename: C I Edvard
authors.initials: CI
authors.lastname: Smith
authors.forename: Beston F
authors.initials: BF
authors.lastname: Nore
mesh_terms: D000077329:Agammaglobulinaemia Tyrosine Kinase; D000577:Amides / Q000494:pharmacology; D000818:Animals; D001402:B-Lymphocytes / Q000187:drug effects / Q000201:enzymology; D002478:Cells, Cultured; D004357:Drug Synergism; D004791:Enzyme Inhibitors / Q000494:pharmacology; D020868:Gene Silencing; D049452:Green Fluorescent Proteins; D006412:Hematopoietic Stem Cells / Q000187:drug effects / Q000201:enzymology; D006632:Histamine / Q000378:metabolism; D006801:Humans; D006967:Hypersensitivity / Q000378:metabolism; D008164:Luminescent Proteins / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D008407:Mast Cells / Q000187:drug effects / Q000201:enzymology; D051379:Mice; D009570:Nitriles / Q000494:pharmacology; D009692:Nucleic Acid Heteroduplexes; D011505:Protein-Tyrosine Kinases / Q000187:drug effects* / Q000235:genetics* / Q000378:metabolism; D016372:RNA, Antisense / Q000493:pharmacokinetics / Q000494:pharmacology*; D051381:Rats
chemical_list: D000577:Amides; D004791:Enzyme Inhibitors; C118451:LFM A13; D008164:Luminescent Proteins; D009570:Nitriles; D009692:Nucleic Acid Heteroduplexes; D016372:RNA, Antisense; D049452:Green Fluorescent Proteins; D006632:Histamine; D011505:Protein-Tyrosine Kinases; D000077329:Agammaglobulinaemia Tyrosine Kinase; C000625949:BTK protein, human; C000625951:Btk protein, mouse