Al-1 Mediated Quorum Sensing and Signal Intergration in Vibrio harveyi

描述(申请人提供)：群体感应是细菌细胞间交流的过程，包括产生和检测被称为自体诱导剂的分泌信号分子。群体感应使细菌能够集体调节基因表达，并作为多细胞生物体发挥作用。哈维氏弧菌是革兰氏阴性群体感应细菌的典范，它整合了来自三种不同的自动诱导剂AI-1、AI-2和AI-1的信息，这些信息共同实现了种内和种间的交流。我将表征AI-1/LuxN传感器的相互作用，并确定AI-1如何改变LuxN的信号特性。我将对apo-和holo-LuxN蛋白进行结构分析。AI-1编码的信息与另外两个哈维氏弧菌自动诱导子整合，以控制群体感应行为。这些信息汇聚在一起，调节四个冗余的小调节RNA(SRNAs)的表达。我将确定群体感应自动诱导子如何精确控制sRNA的表达。对编码sRNA调控元件的DNA的启动子分析表明，额外的转录调控因子调节每个sRNA的水平。我将确定和描述sRNA的其他调控因子。

DESCRIPTION (provided by applicant): Quorum sensing is a process of bacterial cell-cell communication that involves production and detection of secreted signal molecules called autoinducers. Quorum sensing allows bacteria to collectively regulate gene expression and function as multicellular organisms. The model Gram-negative quorum sensing bacterium, Vibrio harveyi integrates information from three different autoinducers, CAI-1, AI-2 and AI-1 that together enable intra- and inter-species communication. I will characterize the AI-1/LuxN sensor interaction and determine how AI-1 alters the signaling properties of LuxN. I will perform structural analyses of apo- and holo- LuxN protein. AI-1 encoded information is integrated with the two other V. harveyi autoinducers to control quorum-sensing behavior. This information converges to regulate expression of four redundant small regulatory RNAs (sRNAs). I will determine how the quorum sensing autoinducers precisely control the expression of the sRNAs. Promoter analysis of the DNA encoding the sRNA regulatory elements suggests that additional transcriptional regulators modulate the level of each sRNA. I will identify and characterize additional regulators of the sRNAs.