Heinonen Juhana E, Smith C I Edvard, Nore Beston F
Clinical Research Center (CRC), KFC-Novum, Karolinska Institutet, Huddinge University Hospital, SE-141 86, Huddinge, Sweden
FEBS Lett. 2002 Sep 11;527(1-3):274-8. doi: 10.1016/s0014-5793(02)03206-4.
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.
Tec家族酪氨酸激酶，布鲁顿酪氨酸激酶（Btk）、白细胞介素-2诱导型T细胞激酶（Itk）、Bmx、Tec和Txk，是参与造血信号传导的多结构域蛋白。在此，我们证明使用双链短RNA干扰（siRNA）寡核苷酸可短暂耗尽人Btk蛋白。成像和蛋白质免疫印迹分析表明，在转染或显微注射Btk siRNA双链体后，Btk表达在异源系统以及造血谱系中均下调。Btk下调后，RBL-2H3肥大细胞中促炎介质组胺释放的诱导减少了20%-25%。使用激酶阻滞剂LFM-A13抑制Btk活性时，也获得了类似结果。这些结果证明了Btk在过敏反应中组胺有效分泌方面的直接作用。
