Regulation of gp91phox by Anaplasma phagocytophila

吞噬细胞无形体对 gp91phox 的调节

• 批准号: 7059877
• 负责人: VENETTA THOMAS
• 金额: $ 12.33万
• 依托单位: YALE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-05-01 至 2008-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7059877
• 关键词: NAD(P)H dehydrogenase; Rickettsiales; bacteria infection mechanism; enzyme structure; gene induction /repression; genetic promoter element; lactoferrin; leukocyte oxidative burst; phosphorylation; posttranslational modifications; protein binding; transcription factor

DESCRIPTION (provided by applicant): Human granulocytic ehrlichiosis is an emerging infectious disease caused by the tick-borne pathogen Anaplasma phagocytophila. A. phagocytophila is an obligate intracellular pathogen with tropism for neutrophils. The mechanism by which this organism survives within this hostile environment remains to be fully elucidated. One survival mechanism utilized by this pathogen may be the result of inhibiting the potent antimicrobials generated by the oxidative burst. A. phagocytophila inhibition of the oxidative burst has been correlated with the down-regulation of gp91phox, an integral component of NADPH oxidase, the facilitator of oxidative burst. The manner of transcriptional inhibition is unknown. I propose that A. phagocytophila inhibits gp91phox expression by modulating the activators and repressor that regulate expression of this gene. My preliminary data reveal that there may be several facets to A. phagocytophila's effect on the expression of gp91 phox. Infection results in enhanced interaction of the repressor with the promoter of gp91phox. CDP binds to 6 separate sites within the promoter of gp91phox. Infection enhanced the interaction of CDP with all sites tested. Infection also resulted in tyrosine phosphorylation of a protein with a molecular weight similar to that of CDP. In addition, transcription of lactoferrin, a second CDP regulated gene, is also down-regulated. The repressor was not the only protein to be affected by infection. Protein concentrations of IRF-1 and PU 1, two transcription activators which regulate the expression of gp91phox were modulated during infection. IRF-1 was affected at the transcription level while PU.1 was affected at the protein level. Based on these results, I hypothesize that A. phagocytophila modulates the expression of gp91 phox by targeting the proteins that interact with the promoter. Aim 1. To determine the effect of A. phagocytophila infection on CCAAT displacement protein (CDP), a major repressor of gp91phox. Aim 2. To define the effect of A. phagocytophila infection on the activity of the activator proteins and their binding capacity of the gp91phox promoter.

描述（由申请人提供）： 人类粒细胞性eHrllichiois是一种由tick传播的病原体吞噬吞噬作用引起的新兴传染病。 A.吞噬tophiphila是一种质性的细胞内病原体，伴有嗜中性粒细胞。 这种生物在这种敌对环境中生存的机制尚待充分阐明。 该病原体使用的一种生存机制可能是抑制氧化爆发产生的有效抗菌剂的结果。 A.氧化爆发的吞噬细胞抑制与氧化爆发的促进剂NADPH氧化酶的积分成分GP91Phox的下调有关。 转录抑制的方式尚不清楚。我提出，吞噬曲霉曲霉通过调节调节该基因表达的激活剂和阻遏物来抑制GP91PHOX的表达。 我的初步数据表明，吞噬曲霉对GP91 Phox表达的影响可能有几个方面。感染导致阻遏物与GP91Phox的启动子的相互作用增强。 CDP与GP91Phox启动子内的6个单独位点结合。感染增强了CDP与所有测试地点的相互作用。 感染还导致了与CDP相似的蛋白质的酪氨酸磷酸化。 另外，第二CDP调控基因的乳铁蛋白的转录也被下调。 阻遏物并不是唯一受感染影响的蛋白质。 IRF-1和PU 1的蛋白质浓度，两个调节GP91Phox表达的转录激活剂在感染过程中调节。 IRF-1在转录水平上受到影响，而PU.1在蛋白质水平上受到影响。 基于这些结果，我假设A. phocytophila通过靶向与启动子相互作用的蛋白质来调节GP91 Phox的表达。 目的1。确定吞噬曲霉感染对GP91Phox的主要阻遏物CCAAT位移蛋白（CDP）的影响。 目的2。定义吞噬曲霉感染对激活蛋白活性及其GP91Phox启动子的结合能力的影响。