Flati V, Haque S J, Williams B R
Department of Cancer Biology, Cleveland Clinic Foundation, OH 44195, USA.
EMBO J. 1996 Apr 1;15(7):1566-71.
Treatment of cells with interferon (IFN)-alpha caused phosphorylation and activation of cytosolic phospholipase A2 (cPLA2). The protein tyrosine kinase Jak1 was found to be necessary for the activation of cPLA2. Jak1 could be co-immunoprecipitated with cPLA2 from cell extracts, indicating that a close physical interaction occurs between these two proteins. The induction of IFN-stimulated gene factor three (ISGF3) by IFN-alpha, is blocked by cPLA2 inhibitors in cell cultures and in cell-free reconstituted systems. However, these inhibitors do not block IFN-alpha or gamma-induced binding of STAT1 to the inverted repeat (IR) element of the IFN regulatory factor 1 (IRF-1) gene. Thus, cPLA2 activations occurs as an early event in the IFN-alpha response and is selectively involved in ISGF3-dependent gene activation.
用α干扰素（IFN-α）处理细胞会导致胞质磷脂酶A2（cPLA2）磷酸化并激活。发现蛋白酪氨酸激酶Jak1是激活cPLA2所必需的。Jak1可与细胞提取物中的cPLA2进行共免疫沉淀，表明这两种蛋白之间存在紧密的物理相互作用。在细胞培养物和无细胞重组系统中，cPLA2抑制剂可阻断IFN-α对干扰素刺激基因因子3（ISGF3）的诱导。然而，这些抑制剂并不阻断IFN-α或γ诱导的信号转导和转录激活因子1（STAT1）与干扰素调节因子1（IRF-1）基因反向重复序列（IR）元件的结合。因此，cPLA2激活是IFN-α应答中的早期事件，并选择性地参与依赖ISGF3的基因激活。
