PHOSPHATE CONTROL OF THE ESCHERICHIA COLI PHO REGULON

描述：Wanner博士描述了一系列旨在 阐明三个关键蛋白，Phor，Phob和Phou(PstB)的作用， 参与了无机磷信号的传递。Phor和Phob共同发挥作用 作为传感器-调节器对，它们是两个大家庭的成员 组件监管系统。感应器phor，它是一个整体 膜蛋白，被认为是感觉胞质外的PI水平 薄膜。磷酸盐饥饿刺激phor使pho B磷酸化， 然后启动许多PI饥饿诱导蛋白(Psi)的表达 基因，之前由Wanner博士描述。无机物的修复 磷酸盐导致Phob去磷酸化和psi基因失活 表情。Phou和或PstB被认为是 停用过程。该系统的另一个特点是在高电压下抑制 磷酸盐水平被认为是由于一种 包括Phor、Phou、PstB在内的蛋白质与高密度脂蛋白的复合体 亲和磷酸盐转运。 该建议有三个具体目标：(一)确定 与Phor和Phou(II)相互作用的PHOB区域(S)确定 磷酸酶和磷酸酶活性是如何调节的，有哪些区域 Phor与Phob和Phou相互作用并识别PI信号域 蛋白质(III)确定Phou和/或PstB在失活PstB中的作用 PSI基因的表达并确定这些蛋白的区域 负责PHB和PHO的识别。这三个目标的共同之处是 PHOB、PHOR和PHOU相互作用的想法。

DESCRIPTION: Dr. Wanner describes a series of experiments designed to elucidate the role of three key proteins, PhoR, PhoB and PhoU (PstB), involved in inorganic phosphate signalling. PhoR and PhoB function together as a sensor-regulator pair and are members of the large family of two component regulatory systems. The sensor PhoR , which is an integral membrane protein, is thought to sense Pi levels outside the cytoplasmic membrane. Phosphate starvation stimulates PhoR to phosphorylate PhoB which then functions to turn on expression of many Pi starvation inducible (psi) genes, previously characterized by Dr. Wanner. Restoration of inorganic phosphate results in dephosphorylation of PhoB and deactivation of psi gene expression. PhoU and or PstB are thought to be essential for the deactivation process. Another feature of the system is inhibition at high phosphate levels which is thought to be due to sequestration of PhoB by a complex of proteins including PhoR, PhoU, PstB and proteins involved in high affinity phosphate transport. There are three specific aims in the proposal: (i) to determine the region(s) of PhoB that interact with PhoR and with PhoU (ii) to determine how PhoR kinase and phosphatase activities are regulated, what regions of PhoR interact with PhoB and PhoU and to identify the Pi signal domain in the protein (iii) to determine the role of PhoU and or PstB in deactivation of psi gene expression and to determine the regions of these proteins responsible for PhoB and PhoR recognition. Common to the three aims is the idea that PhoB, PhoR and PhoU interact.