Biochemical and structural characterization of RNA turnover processes and resolu

项目负责人：Dinshaw Patel。该项目的主要目的是对一类自身抗原的天然功能进行生物化学和结构表征，这些抗原在压力下释放，并可能引发强烈的先天免疫反应，最终导致自身抗体的产生。细胞外RNA是先天免疫的有效激活剂， 通过与存在于大多数细胞中的内体和细胞内模式识别受体结合而感知的系统 包括吞噬细胞。免疫刺激性细胞外RNA的最熟知来源是 病毒。然而，RNA传感受体本身不能严格区分自身核酸。 acids.因此，导致宿主细胞RNA被摄取到邻近细胞中的细胞应激事件， 然后激活模式识别受体，可能代表了一种合理的机制， 启动。自身免疫性疾病的特点是存在高滴度的抗核抗体 (ANA)，可能是由于神经元的感觉机制被不适当地激活而导致的病理表现。 应激诱导的含RNA颗粒。我们建议： (1)鉴定RBP自身抗原包括SSB/La、TROVE 2/SSA 2/Ro 60和TROVE 2/SSA 2/Ro 60的RNA结合靶标。 TRIM 21/SSA 1/Ro 52在正常和应力条件下使用PAR-CLIP。开发新的生化分析 其再现了RNA颗粒的形成或使用重组蛋白质的它们的分解。 (2)研究pol Ⅲ RNA转录本结合因子在逆境中的作用及其具体结构和功能 SSB/La、TROVE 2/SSA 2/R 060和TRIM 21/SSA 1/R 052与它们的体内RNA靶的杂交。研究如何 应激条件影响tRNA的加工模式，例如多聚尿苷酸化。 (3)确定pol III RNA转录物加工的机制和结构，涉及tRNA特异性 核糖核酸内切酶TSN-TSNAX/C3 P0和模式识别受体RIG-1和MDA 5复合物， 体内RNA靶点，并研究其在应激条件下的扰动

Project Leader: Dinshaw Patel. The broad aim of this project is the biochemical and structural characterization of the natural function of a class of autoantigens that are released upon stress and may trigger strong innate immune responses that ultimately result in autoantibody production. Extracellular RNA is a potent activator of the innate immune system sensed by binding to endosomal and intracellular pattern recognition receptors present in most cells including phagocytic cells. The most well known sources of immunostimulatory extracellular RNA are viruses. However, RNA sensing receptors by themselves cannot discriminate stringently against self-nucleic acids. Thus, events of cellular stress that lead to the uptake of host cell RNA into neighboring cells, which then activates pattern recognition receptors, may represent a plausible mechanism by which autoimmunity is initiated. Autoimmune disorders are characterized by the presence of high titers of antinuclear antibodies (ANA), and may be the pathologic manifestations of inappropriate activation of sensing mechanisms by stress-induced RNA-containing granules. We propose to: (1) Identify the RNA binding targets of RBP autoantigens including SSB/La, TROVE2/SSA2/Ro60 and TRIM21/SSA1/Ro52 under normal and stress conditions using PAR-CLIP. Develop new biochemical assays that recapitulate the formation of RNA granules or their resolution using recombinant proteins. (2) Study the role of pol III RNA transcript binding factors during stress and the specific structure and function of SSB/La, TROVE2/SSA2/RO60 and TRIM21/SSA1/Ro52 with their in vivo RNA targets. Investigate how stress conditions influence the processing patterns of tRNAs, e.g. polyuridylation. (3) Determine the mechanism and structure of pol III RNA transcript processing involving the tRNA-specific endoribonuclease TSN-TSNAX/C3P0 and pattern recognition receptor RIG-1 and MDA5 complexes with their in vivo RNA targets, and investigate their perturbation under stress conditions