Analysis of tyrosine kinase chimeric gene

点击翻译按钮获取中文摘要

We here investigate the intracellular signal transduction of the stable transfectants. TEL-Syk fusion protein was associated with p85 subunit of phosphatidyl inositol 3 kinase (PI3-K) followed by the activation of Akt in the absence of IL-3. Vav, phospholipase C-γ2 (PLC-γ2) and mitogen-activated protein kinase (MAPK) were also constitutively activated. TEL-Syk also activated signal transducer and activator of transcription (STAT) 5 in the absence of Janus kinase 2 (JAK2) activation. None of these kinases were phosphorylated in the BaF3 cell transfected with TELΔPNT-Syk in which the oligomerization domain of TEL was deleted. Piceatannol, the Syk specific kinase inhibitor, inhibited the activation of STAT5 and the growth of the TEL-Syk transformed cell. These data suggest that TEL-Syk fusion protein in cytoplasm leads to constitutive activation of PI3-K, PLC-γ, MAPK and STAT5 signal pathways which are closely involved in IL-3 independent cell proliferation of BaF3 cells.