Regulation of pathogen sensing and inflammation by NLR proteins

项目摘要 NLR（nucleotide-binding domain，leucine-rich repeat containing protein，又称NOD-like receptor） 家族是一组多样的蛋白质，其功能是调节宿主免疫。许多NLR已经被证明 调节炎性小体的形成，控制caspase-1的活化、IL-1 β/IL-18的分泌和炎性 细胞死亡相反，NLR蛋白的一个子集负调节不同的炎症途径，通常是 通过与关键信号分子的抑制性相互作用。尽管如此， 对炎症的负调控知之甚少。特别是NLRC 3已经被证明是负面的， 调节几个关键的炎症通路。例如，NLRC 3已显示抑制NF-κ B和PI3 K 响应TLR（或IGF-1R）信号传导和促炎细胞因子分泌的途径;或者，NLRC 3 通过调节STING来抑制I型干扰素对胞质核酸刺激的应答产生 贩卖人口允许NLRC 3在不同途径中发挥作用的分子机制知之甚少。 了解炎症负调节的分子机制对于研究炎症的发生和发展是必要的。 制定改善健康的新战略。我的建议的目标1使用经典的生物化学和细胞生物学 技术来检查与NLRC 3的新型蛋白质-蛋白质相互作用物的分子决定簇。我们的研究 提示这些相互作用物之一可能通过重新定位而负调节I型干扰素的产生， NLRC 3的细胞皮质。我建议实验来研究这些相互作用是如何介导的。在目标2中 在我的建议中，我们将使用siRNA敲低来研究这些蛋白质-蛋白质相互作用的作用 实验和先进的显微镜，以研究蛋白定位和运输的作用，在NLRC 3- 介导的细胞通路抑制。

Project Summary The NLR (nucleotide-binding domain, leucine-rich repeat containing protein, also known as NOD-like receptor) family is a diverse group of proteins that functions to regulate host immunity. Many of the NLRs have been shown to regulate inflammasome formation and control caspase-1 activation, IL-1β/IL-18 secretion and inflammatory cell death. In contrast a subset of NLR proteins negatively regulates different inflammatory pathways, typically via inhibitory interactions with key signaling molecules. Nonetheless the molecular mechanisms that control the negative regulation of inflammation are poorly understood. NLRC3 in particular has been shown to negatively regulate several key inflammatory pathways. For example, NLRC3 has been shown to inhibit NF-κB and PI3K pathways in response to TLR (or IGF-1R) signaling and proinflammatory cytokine secretion; alternatively, NLRC3 inhibits type I interferon production in response to cytosolic nucleic acid stimulation by regulating STING trafficking. The molecular mechanisms to allow for NLRC3 to function in diverse pathways are poorly understood. Understanding the molecular mechanisms of negative regulation of inflammation will be necessary for the generation of new strategies to improve health. Aim 1 of my proposal uses classic biochemical and cell biological techniques to examine the molecular determinants of novel protein-protein interactors with NLRC3. Our studies suggest that one of these interactors negatively regulates type I interferon production possibly by relocating NLRC3 to the cell cortex. I propose experiments to investigate how these interactions are mediated. In Aim 2 and 3 of my proposal, we will investigate the role of these protein-protein interactions using siRNA knockdown experiments and advanced microscopy to investigate the role of protein localization and trafficking in NLRC3- mediated inhibition of cellular pathways.