Genomics of Gene Regulation in Porphyromonas gingivalis

描述（由申请人提供）：破译感染过程中细菌和宿主之间的“对话”是理解微生物发病机制和宿主防御的核心。牙周病长期以来被认为是细菌感染，实验室的长期目标是鉴定感染过程中表达的牙龈假单胞菌基因。细菌和寄主之间相互作用的一面。生物体的遗传可追溯性，加上完整的基因组序列和基因微阵列的可用性，使这一目标变得可行。细菌使用双组分信号转导系统来监测其环境的变化并作出反应。在这个应用程序中，我们测试的假设，在牙龈假单胞菌这些系统是响应在健康和疾病期间普遍存在于龈下缝隙的体内条件。本文对牙龈卟啉单胞菌基因调控的分子机制进行了全面的研究，这是牙龈卟啉单胞菌研究的一个新领域。将分析反应调节因子以确定它们控制的基因及其启动子目标。我们将通过在牙周炎患者的牙龈下菌斑的体内环境中确定一组已识别基因的表达来验证我们的假设。实验方法利用我们在分子遗传学，全基因组转录谱，启动子目标定位和DNA序列分析方面的经验。目标是响应RFA，因为我们将分析牙龈假单胞菌胞内信号机制，协调对环境变化的反应。通过确定这些调节因子、它们所控制的基因以及它们在体内和体外的表达模式，我们可以识别可能引发牙周炎的条件，并针对调节分子开关进行合理的治疗干预。

DESCRIPTION (provided by applicant): Deciphering the "conversation" between bacterium and host during infection is central to understanding microbial pathogenesis and host defense. Periodontal diseases have long been recognized as bacterial infections, and a long-term goal of the laboratory is to identify P. gingivalis genes expressed during infection, ie. one side of the cross-talk between bacterium and host. The genetic tractability of the organism, combined with the availability of a completed genome sequence and gene microarrays, has made this goal approachable. Bacteria use two-component signal transduction systems to monitor and react to changes in their environment. In this application, we test the hypothesis that in P. gingivalis these systems are responsive to in vivo conditions prevailing in the subgingival crevice during health and disease. A comprehensive study is proposed of the molecular mechanisms of gene regulation in P. gingivalis, a new area of research with this organism. Response regulators will be analyzed to identify the genes they control, and their promoter targets. We will test our hypothesis by determining the expression of a subset of identified genes in the in vivo environment of subgingival plaque from periodontitis patients. The experimental approaches exploit our experience in molecular genetics, whole genome transcription profiling, promoter target localization, and DNA sequence analysis. The goals are responsive to the RFA since we will analyze P. gingivalis intracellular signaling mechanisms that orchestrate responses to environmental changes. By defining the regulators, the genes they control, and their in vitro and in vivo expression patterns, we can identify conditions that may trigger periodontitis, and target rational therapeutic interventions to the regulatory molecular switches.