Cellular Signaling by Double-Stranded RNA

Toll样受体TLRs介导的两种新的炎症反应抑制机制 转录因子LRF-3将在细胞和生物水平上进行研究。TLRS是一种传感器 双链RNA，在对病毒感染的直接先天反应的背景下进行了研究。 但TLRs也可以调节对多种组织产生的内源性细胞dsRNA的反应 受伤。本资助期的主要发现之一是酪氨酸的磷酸化 TLRs中的残基对于其启动信号的能力是必不可少的。在具体目标1，轮胎的调节 TLRs的磷酸化将被研究，重点是酪氨酸激酶活性的作用。 我们发现的与TLRs相互作用的EGF受体。TLRS的一个独特属性是它的独有用途 转录因子IRFS和NFKB激活的适配蛋白TRIF。令人惊讶的是，我们有 发现了一种非TRIF依赖的TLRs活性，需要招募和激活原核 癌基因Src并导致抑制细胞迁移。在第二个具体目标中，对和的要求 将定义TLRs激活Src的后果，以及细胞和生理后果 被评估。最后，我们最近观察到，IRFS对PRO有显著的抑制作用 炎性转录因子，NFKB。第三个具体目标将确定两者的结构特征 调节它们的物理相互作用并决定生物化学、细胞和生理的蛋白质 这种互动的后果。拟议中的实验将检验TLRs及其 关联的组件与刺激(DsRNA)依赖和独立的功能相结合，这些功能 共同影响促炎基因的表达和促炎白细胞的运输。 这些功能可能以细胞类型和组织受限的方式运行，并具有重大影响 炎症性疾病及其在肿瘤发生中的相关作用。与项目2、S、4和 核心B对于评估这些功能及其控制将如何影响与炎症相关的 肿瘤发生学。 相关性(请参阅说明)： 拟议的研究结果将阐明TLRs信号通过抑制TLRs的抗炎作用 炎性细胞迁移和抑制炎症基因诱导的IRF-S的迁移。他们会 还将两种癌蛋白，Src和EGF受体的作用与TLRs信号联系起来，从而揭示了一种新的 炎症和癌症之间相互作用的方面。

Two new mechanisms of suppression of inflammatory responses, mediated by the Toll-like receptor, TLRS and the transcription factor, lRF-3, will be studied at the cellular and organismal levels. TLRS is a sensor of double-stranded RNA and has been studied in the context of immediate innate responses to virus infection. But TLRS can also mediate response to endogenous cellular dsRNAs generated during a vahety of tissue injuries. One ofthe major findings in the current funding period was that the phosphorylation of tyrosine residues in TLRS is essential for its ability to initiate signaling. In specific aim 1, the regulation of Tyr phosphorylation of TLRS will be investigated with emphasis upon the role of the tyrosine-kinase activity of EGF receptors, which were found by us to interact with TLRS. A unique property of TLRS is its exclusive use of the adaptor protein TRIF for the activation of transcription factors IRFS and NFKB. Surprisingly, we have discovered a TRIF-independent activity of TLRS that requires the recruitment and activation of the proto¿¿ oncogene Src and causes inhibition of cell migration. In the second specific aim, the requirements for and consequences of Src activation by TLRS will be defined and the cellular and physiologic consequences will be evaluated. Finally, we have recently observed that IRFS has a significant suppressive effect on the pro¿¿ inflammatory transcription factor, NFKB. The third specific aim will identify the structural features of the two proteins that mediate their physical interaction, and determine the biochemical, cellular and physiologic consequences ofthis interaction. The proposed experiments will test the hypothesis that TLRS and its associated components are coupled with both stimulus (dsRNA) dependent and independent functions that collectively impact upon pro-inflammatory gene expression and trafficking of pro-inflammatory leukocytes. These functions are likely to operate in a cell type and tissue restricted fashion and have significant impact on inflammatory disease and the associated effect on tumorigenesis. Interactions with projects 2, S, 4 and core B will be essential to assess how these functions and their control will impact inflammation related tumongenesis. RELEVANCE (See instructions): Results from the proposed studies will shed light on the anti-inflammatory role of TLRS signaling by inhibiting inflammatory cell migration and that of IRF-S by inhibiting inflammatory gene induction by NFkB. They will also connect the actions of two oncoproteins, Src and EGF receptor, to TLRS signaling, thus revealing a new aspect of interplay between inflammation and cancer.