Role of PARP-1 in Mediating Inflammatory Gene Transcription

炎症介质的过度产生可能导致主要器官衰竭和损害。这个 转录一组确定的炎症基因需要同时特定的DNA蛋白和 蛋白质与蛋白质在称为增强体的高度有序的复合体中相互作用。聚(ADP-核糖) 聚合酶-1(PARP-1)调节负责炎症基因表达的转录因子，以及 重要的是，PARP-1缺陷(PARP-1-/-)小鼠被证明对炎症性疾病具有抵抗力。 总体假设是PARP-1被招募到启动子，修改转录 调节子与聚(ADP-核糖)结合，并介导招募转录调节子来组装 协同基因转录的增强体。我们的具体目标是(1)确定PARP是否- 1以序列特异性的方式结合iNOS启动子；(2)研究PARP-1是否被招募到iNOS 与序列特异性转录因子(S)相互作用并增加其DNA结合的启动子 (3)研究p42/44MAPK是否直接或间接磷酸化并诱导PARP-1 内毒素的催化活性；(4)确定PARP-1是否靶向转录调控因子 Poly(ADP-核糖)用于有效转录内毒素；(5)表征PARP-1介导的 转录调节因子对启动子的招募(I)通过比较野生型和PARP-1-/-细胞， (Ii)通过同时分析PARP-1介导的招聘，以及(Iii)iNOS、TNFpha、IL-1β和 IL-6；(6)确定PARP-1的特异性及其对炎症基因的催化活性 野生型PARP-1和催化失活PARP-1突变体在PARP-1-/-细胞中的表达调控 拟议研究的意义在于为(S) PARP-1可能通过调控和被调控来实现炎症基因的协同转录。这个 炎性基因转录对免疫反应和确定发病起关键作用 炎症性疾病，如感染性休克、急性肺部炎症、阿尔茨海默病、多发性 硬化症和艾滋病毒相关性痴呆症。

Overproduction of inflammatory mediators can lead to major organ failure and damage. The transcription of a defined set of inflammatory genes requires the simultaneous specific DNA-protein and protein-protein interactions in highly ordered complexes called enhanceosome. Poly(ADP-ribose) polymerase-1 (PARP-1) regulates transcription factors responsible for inflammatory gene expression, and importantly PARP-1-deficient (PARP-1-/-) mice were shown to be resistant to inflammatory diseases. The overall HYPOTHESES are that PARP-1 is recruited to the promoter, modifies transcription regulators with poly(ADP-ribose), and mediates recruiting transcription regulators to assemble the enhanceosome for synergistic gene transcription. Our SPECIFIC AIMS are to (1) determine whether PARP- 1 binds the iNOS promoter in a sequence-specific manner; (2) investigate if PARP-1 is recruited to the iNOS promoter by interacting with a sequence-specific transcription factor(s) and increasing its DMA binding activity; (3) investigate whether p42/44MAPK directly or indirectly phosphprylates and induces PARP-1 catalytic activity in response to LPS; (4) determine whether PARP-1 targets transcription regulators with poly(ADP-ribose) for the efficient gene transcription in response to LPS;(5) characterize PARP-1 mediating the recruitment of transcription regulators to the promoters (i) by comparing wild-type and PARP-1-/- cells, (ii) by simultaneously analyzing PARP-1-mediated recruitments, and (iii) of iNOS, TNFalpha, IL-1beta, and IL-6; and (6) definitively determine the specificity of PARP-1 and its catalytic activity on inflammatory gene regulation by expressing wild-type PARP-1 and catalytically inactive PARP-1 mutant in PARP-1-/- cells. The SIGNIFICANCE of the proposed studies is to offer new insights into the mechanism(s) by which PARP-1 may regulate and be regulated to achieve synergistic inflammatory gene transcription. The inflammatory gene transcription is critical for immune responses and for determining the onset of inflammatory diseases such as septic shock, acute lung inflammation, Alzheimer's disease, multiple sclerosis, and HIV-associated dementia.