RAP PHOSPHATASES

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得主要资金， 因此可以在其他CRISP条目中表示。列出的机构是 中心，不一定是研究者的机构。 群体感应是一种细菌细胞间的通讯过程，允许细菌群体一致行动，同步重要的表型变化。 一个被称为Phr五肽的分泌型群体感应信号家族被导入细胞，在细胞中它们抑制被称为Raps的蛋白质的活性。 为了确定Rap蛋白如何在机制上发挥作用，以及Rap功能如何反过来受到Phr肽的调节，我们正在研究枯草芽孢杆菌Rap蛋白的两个子集。 一个Rap蛋白亚群负调控B中的孢子形成。Rap蛋白的另一个亚类通过使芽孢形成信号转导途径中的中心蛋白脱磷酸化而下调枯草芽孢杆菌的遗传感受态，Rap蛋白的另一个亚类通过阻止早期感受态基因表达的主转录调节因子与靶DNA启动子结合而下调遗传感受态的发育。 我们已经将Rap蛋白与其靶效应蛋白以及其调节Phr肽复合结晶。 这些复合物的X射线晶体结构，结合生物化学和遗传学研究，将首次揭示Rap蛋白的功能机制以及Phr肽如何调节Rap蛋白的活性。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Quorum sensing is a bacterial cell-cell communication process that allows groups of bacteria to act in unison, synchronizing important phenotypic changes. One family of secreted quorum-sensing signals, called Phr pentapeptides, is imported into the cell where they inhibit the activity of proteins called Raps. To determine how Rap proteins function mechanistically, and how Rap functions are in turn regulated by Phr peptides, we are studying two subsets of Bacillus subtilis Rap proteins. One Rap protein subset negatively regulates sporulation in B. subtilis by dephosphorylating a central protein in the sporulation signal transduction pathway, the other subset of Rap proteins downregulates the development of genetic competence by preventing the master transcriptional regulator of early competence gene expression from binding to target DNA promoters. We have crystallized Rap proteins in complex with their target effector proteins, as well as with their regulatory Phr peptides. The X-ray crystal structures of these complexes, combined with biochemical and genetic studies, will reveal for the first time how Rap proteins function mechanistically and how Phr peptides regulate Rap protein activity.