IFNARI SIGNALING THROUGH STAT3, PI 3 KINASE

通过 STAT3、PI 3 激酶的 IFNARI 信号传导

• 批准号: 6475950
• 负责人: LAWRENCE MARC PFEFFER
• 金额: $ 30.15万
• 依托单位: UNIVERSITY OF TENNESSEE HEALTH SCI CTR
• 依托单位国家: 美国
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-12-02 至 2002-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6475950
• 关键词: DNA binding protein; SDS polyacrylamide gel electrophoresis; antiviral agents; apoptosis; biological response modifiers; biological signal transduction; cell growth regulation; densitometry; gene expression; immunoprecipitation; interferon alpha; northern blottings; nuclear factor kappa beta; nuclear runoff assay; phosphatidylinositol 3 kinase; phosphorylation; protein kinase C; protein structure function; receptor binding; receptor coupling; tissue /cell culture; transcription factor; western blottings

Interferon-alpha (IFNalpha) is a multifunctional cytokine, which is clinically effective in the treatment of human malignancies, viral infections and auto-immune diseases. IFNalpha elicits pleiotropic biological effects by regulating gene expression through signals generated upon its binding to a surface receptor on target cells (IFNalphaR). The first cloned subunit of the IFNalphaR, IFNAR1, plays a decisive role as a IFN signal transducing subunit but does not directly bind IFNalpha. The IFNalpha-induced tyrosine phosphorylation of STAT transcription factors is crucial in activated protein kinase (ERK2) also contribute to IFNalpha action. Based on the applicant's recent studies, the hypothesis to be tested is that via the IFNalpha-induced binding of STAT3 to the IFNalphaR, STAT3 (a transcription factor regulation the acute phase response genes), couples IFNalphaR signaling to pathways involving PI-3 kinase (phosphatidylinositol-3' kinase, an upstream element in a serine kinase transduction cascade), NF-kappaB (nuclear factor-kappaB, a transcription factor for genes important in inflammation and preventing apoptosis), and serine kinases (PKC subspecies and ERK2). In Specific Aim 1, how STAT3 acts as an adapter to couple IFNalpha signaling pathways will be characterized. To be determined is if STAT3 activation (specifically via the docking domain in STAT3 for the p85 subunit of PI-3 kinase) is required for IFNalpha-induced: PI-3 kinase activation, PKC activation, ERK2 activation, gene expression, anti-viral action, and the anti- proliferative action. In Specific Aim 2, the role of PI-3 kinase arm of the STAT3-signaling pathway in IFNalpha action will be defined. The effect of expressing dominant negative and constitutively active PI-3 kinase constructs will be examined on IFNalpha-induced: serine phosphorylation of cellular substrates, PKC activation, ERK2 activation, DNA-binding activity, gene expression, anti-viral action, anti-proliferative action, and inhibition of programmed cell death. In specific Aim 3, the role of the NF-kappaB component of the STAT3-signaling pathway in IFNalpha action will be defined. To be determine are the mechanism for NF-kappaB activation, the interaction of STAT3 with NF-kappaB proteins, and the role of NF-kappaB activation on IFNalpha-induced: gene expression, anti-viral activity, anti-proliferative activity, inhibition of programmed cell death. The overall goal of these studies to determine how the activation of STAT3, PI-3 kinase and NF-kappaB are linked, and to determine their roles in effecting IFN's biological actions.

干扰素-alpha（ifnalpha）是一种多功能细胞因子，是 临床有效治疗人类恶性肿瘤，病毒 感染和自身免疫性疾病。 ifnalpha引起多效性 通过产生的信号调节基因表达来调节生物学作用 它与靶细胞（IFNALPHAR）上的表面受体结合后。这 ifnalphar的第一个克隆亚基ifnar1起着决定性的作用 IFN信号转导亚基但不直接结合IFNALPHA。这 IFNALPHA诱导的Stat转录因子的酪氨酸磷酸化是 活化蛋白激酶（ERK2）的关键也有助于Ifnalpha 行动。根据申请人的最新研究，假设是 测试的是，通过IFNALPHA诱导的STAT3与Ifnalphar的结合， STAT3（转录因子调节急性相响应基因）， 夫妻IFNALPHAR信号传导涉及PI-3激酶的途径 （磷脂酰肌醇-3'激酶，丝氨酸激酶中的上游元素 Transduction Cascade），NF-kappab（核因子-kappab，转录 在炎症和预防凋亡中重要的基因因素）和 丝氨酸激酶（PKC亚种和ERK2）。在特定目标1中，如何Stat3 充当夫妇IFNALPHA信号通路的适配器 特征。待确定是IF STAT3激活（特别是通过 STAT3中的对接域的P85亚基PI-3激酶是） IFNALPHA诱导的需要：PI-3激酶激活，PKC激活， ERK2激活，基因表达，抗病毒作用和抗 - 增殖作用。在特定的目标2中，PI-3激酶组的作用 将定义IFNALPHA动作中的STAT3信号途径。效果 表达显性的负阴性和组成性活性PI-3激酶 将在ifnalpha诱导的：丝氨酸磷酸化上检查构建体 细胞底物，PKC激活，ERK2激活，DNA结合 活性，基因表达，抗病毒作用，抗增殖作用， 并抑制程序性细胞死亡。在特定的目标3中， Ifnalpha动作中Stat3信号途径的NF-kappab组件 将定义。确定是NF-kappab的机制 激活，STAT3与NF-kappab蛋白的相互作用以及该作用 ifnalpha诱导的NF-kappab激活：基因表达，抗病毒 活性，抗增殖活性，抑制程序细胞 死亡。这些研究的总体目标是确定激活如何 STAT3，PI-3激酶和NF-kappab已连接，并确定它们 在影响IFN的生物学作用中的作用。