Anaplasma phagocytophilum modulate tick gene expression for its survival and transmission from the vector host

项目概要/摘要 人类无形体病由专性细胞内细菌嗜吞噬细胞无形体引起， 是美国最常见的蜱传疾病之一。在哺乳动物和蜱类中，A. 嗜吞噬细胞菌分别存在于嗜中性粒细胞和唾液腺中。尽管有许多研究表明， 一直专注于理解A.嗜吞噬细胞菌用于在哺乳动物体内生存 细胞，相对较少的研究已经清楚地定义了分子策略，A。嗜吞噬细胞菌用于 在蜱虫中生存在这个项目中，我们将对硬蜱进行全面的分子分析， 肩胛骨有机阴离子转运多肽（OATPs）和色氨酸相关基因 代谢途径。嗜吞噬细胞-蜱相互作用这项研究是建立在我们的努力， 显示A.嗜吞噬细胞菌调节基因表达和细胞信号转导，以维持其在细胞中的存活。 vector.作为一个例子，我们以前的研究表明，A。嗜吞噬细胞菌调节蜱抗冻剂 基因表达和肌动蛋白磷酸化以使其在载体中存活。在这里，我们提供强大的 初步的体外和体内数据表明，A.嗜吞噬细胞菌诱导一种特异性 OATP（OATP 4056）和犬尿氨酸氨基转移酶（KAT），一种参与色氨酸途径的基因。 我们现在假设OATP 4056和KAT之间的相互作用不仅促进A. 嗜吞噬细胞菌在载体中的存活，而且还有助于将这种细菌传播到 脊椎动物宿主RNAi分析表明，OATP 4056的敲低对A. 嗜吞噬细胞的收购，但影响其生存和传播这些蜱。电泳 用启动子区和从未感染和A. 嗜吞噬细胞菌感染的蜱提供了进一步的证据，表明这种细菌的存在影响 OATP 4056在这些蜱中的表达。另外，我们发现色氨酸的代谢物 pathway调节A.嗜吞噬细胞存活和OATP 4056基因表达。这些 结果为我们提出的研究提供了重要的见解，以确定 A.嗜吞噬细胞蜱基于我们强有力的初步结果和实验建议，我们 我相信这可能是一项变革性的研究，不仅可以作为研究亲密关系的模型， 病原体与其节肢动物媒介建立的关系，但也可能导致发展 新的策略，以中断这种和其他立克次体物种的医疗传播， 重要性

Project Summary/Abstract Human anaplasmosis, caused by the obligate intracellular bacterium Anaplasma phagocytophilum, is one of the most common tick-borne diseases in the United States. In mammals and ticks, A. phagocytophilum resides in neutrophils and in salivary glands, respectively. Despite numerous studies that have focused on understanding strategies that A. phagocytophilum uses to survive in the mammalian cells, relatively few studies have clearly defined the molecular strategies that A. phagocytophilum uses to survive in ticks. In this project, we will be performing a comprehensive molecular analysis on Ixodes scapularis organic anion transporting polypeptides (OATPs) and genes involved in the tryptophan metabolism pathway in A. phagocytophilum-tick interactions. This study is build upon our efforts in showing how A. phagocytophilum modulates gene expression and cell signaling for its survival in the vector. As an example, our previous studies has shown that A. phagocytophilum modulate tick antifreeze gene expression and actin phosphorylation for its survival in the vector. Here, we provide strong preliminary in vitro and in vivo data showing that A. phagocytophilum induces expression of a specific OATP (OATP4056) and kynurenine aminotransferase (KAT), a gene involved in the tryptophan pathway. We now hypothesize that interplay between OATP4056 and KAT not only facilitates A. phagocytophilum survival in the vector but also aid in the transmission of this bacterium to a vertebrate host. RNAi analysis revealed that knockdown of OATP4056 has no effect on A. phagocytophilum acquisition but affected its survival and transmission from these ticks. Electrophoretic mobility shift assays with promoter region and total lysates prepared from uninfected and A. phagocytophilum-infected ticks provide further evidence that the presence of this bacterium influences expression of OATP4056 in these ticks. In addition, we found evidence that a metabolite from tryptophan pathway regulates A. phagocytophilum survival and OATP4056 gene expression in these ticks. These results provide important insights for our proposed studies to define molecular basis of the relationship of A. phagocytophilum with ticks. Based on our strong preliminary results and the experiments proposed, we believe that this could be a transformative study that not only serves as a model to study intimate relationships established by pathogens with their arthropod vectors but may also lead in the development of new strategies to interrupt the transmission of this and perhaps other Rickettsial species of medical importance.