Molecular Mechanisms of Signal Transduction by Two-Component Regulatory Systems

二元调控系统信号转导的分子机制

• 批准号: 9310656
• 负责人: Robert B. Bourret
• 金额: $ 48.58万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-05-01 至 2021-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9310656
• 关键词: Active Sites; Affect; Amino Acid Sequence; Amino Acids; Animals; Antibiotic Resistance; Antibiotics; Architecture; Bacterial Antibiotic Resistance; Behavior; Binding; Biochemistry; Bioinformatics; Biological; Biological Process; Biophysics; Catalysis; Cells; Characteristics; Complex; Crystallization; Data; Dependence; Development; Diabetes Mellitus; Dimerization; Disease; Elements; Engineering; Environment; Eukaryota; Exhibits; Frequencies; Genetic Variation; Goals; Growth; Health; Histidine; Human; Imidazole; Infection; Investigation; Kinetics; Lead; Learning; Life; Malignant Neoplasms; Measures; Microbe; Molecular; Molecular Biology; Monitor; Output; Pharmaceutical Preparations; Phosphoric Monoester Hydrolases; Phosphorylation; Phosphotransferases; Phylogenetic Analysis; Physiology; Planet Earth; Plants; Positioning Attribute; Predisposition; Process; Prokaryotic Cells; Property; Protein Dephosphorylation; Proteins; Reaction; Regulation; Research; Scheme; Self-control as a personality trait; Signal Transduction; Signaling Protein; Stimulus; Structure; System; Testing; Therapeutic Agents; Time; Variant; Virulence; Water; Work; bacterial resistance; biological information processing; cell growth; design; dimer; experience; experimental study; genome sequencing; information processing; innovation; interest; killings; microbial; microorganism; pathogen; response; sensor; small molecule; structural biology

PROJECT SUMMARY The ability to respond to stimuli is often considered to be a key characteristic of life. Cells can detect new conditions, transduce that information into a usable form, and execute an appropriate response. One common signal transduction strategy is to represent information by the specific and transient placement of phosphoryl groups on proteins. Errors in signal transduction can lead to diseases (e.g. cancer, diabetes), and drugs have been developed to block aberrant signaling processes. Understanding the mechanisms, regulation, and impact of protein phosphorylation is thus of fundamental interest, as well as of practical significance to human health. Microorganisms are the dominant form of life on Earth by many measures, including genetic diversity, raw numbers, environmental distribution, and evolutionary experience. Thus, it is logical to seek basic signal transduction principles in microbes. Our long-term goal is comprehensive understanding of signal transduction by two-component regulatory systems, which occur in microorganisms from all three phylogenetic domains, as well as plants. In a basic two-component system, a sensor kinase (SK) detects stimuli and autophosphorylates using ATP. A response regulator (RR) then catalyzes phosphotransfer from the SK (or from small molecules), which turns on the response. RR dephosphorylation, either self-catalyzed or stimulated by another protein, ends the response. Inclusion of histidine-containing phosphotransferase (Hpt) proteins results in more complex multi-step phosphorelays by adding an Hpt and a second RR onto the basic SK to RR scheme. The kinetics and directionality of phosphoryl group reactions are important to synchronize responses with stimuli. Genome sequencing presents a challenge (a rapidly widening gap between the number of known proteins and what can be studied experimentally) and an opportunity (diverse and extensive sequence data). To learn how to reveal properties of hundreds of thousands of two-component proteins from sequence data alone, our innovative research strategy focuses on amino acid sequence differences (rather than similarities) between the conserved domains of SKs, Hpts, or RRs. Our well-established and productive experimental approach integrates biochemistry, bioinformatics, biophysics, molecular biology, and structural biology. In this project, we will identify factors that affect the kinetics of self-catalyzed RR phosphorylation and dephosphorylation (AIM 1), SK-stimulated dephosphorylation of RRs (AIM 2), and phosphotransfer reactions between Hpts and RRs (AIM 3). We will also characterize the molecular mechanisms underlying each of these reactions. Antibiotic resistance of bacterial and fungal pathogens is a major and increasing threat to human health. RRs are central to most phosphotransfer reactions of two-component systems. Our study of binding of small molecules to RRs may influence design of therapeutic agents to disable critical two-component systems of microbial pathogens. The results of our project could also be used to predict or manipulate the signaling kinetics of two-component systems. Fundamental principles of signal transduction may emerge as well.

项目摘要 对刺激的反应能力通常被认为是生活的关键特征。细胞可以检测到新的 条件，将信息转换为可用的形式，并执行适当的响应。一个常见 信号转导策略是通过磷酸化的特定和瞬态放置来表示信息 蛋白质组。信号转导错误可能导致疾病（例如癌症，糖尿病），并且药物具有 已开发以阻止异常信号传导过程。了解机制，调节和影响 因此，蛋白质磷酸化具有基本兴趣，并且对人类健康具有实际意义。 微生物是许多措施，包括遗传多样性，RAW，是地球上生命的主要形式 数字，环境分布和进化经验。因此，寻求基本信号是合乎逻辑的 微生物中的转导原理。我们的长期目标是对信号转导的全面理解 通过在所有三个系统发育结构域中的微生物中发生的两个组分调节系统，AS 和植物。在基本的两个组分系统中，传感器激酶（SK）检测刺激和自磷酸化。 使用ATP。然后，响应调节剂（RR）从SK（或小分子）催化磷酸转移， 打开响应。 RR去磷酸化，由另一种蛋白质自我催化或刺激 结束响应。纳入含有组氨酸的磷酸转移酶（HPT）蛋白会导致更多 通过在RR方案的基本SK中添加HPT和第二个RR来复杂的多步磷。这 磷酸组反应的动力学和方向性对于将反应与刺激同步很重要。 基因组测序提出了挑战（已知蛋白质数量之间的差距迅速扩大 以及可以通过实验研究的）和机会（多样化和广泛的序列数据）。学习 如何仅从序列数据中揭示数十万个两分量蛋白的性能， 创新研究策略的重点是氨基酸序列差异（而不是相似性） SK，HPTS或RR的保守域。我们建立良好且富有成效的实验方法 整合生物化学，生物信息学，生物物理学，分子生物学和结构生物学。在这个项目中， 我们将确定影响自催化的RR磷酸化和去磷酸化动力学的因素（AIM 1），RRS的SK刺激（AIM 2）以及HPT和RR之间的磷酸转移反应 （目标3）。我们还将表征这些反应中每一个的分子机制。 细菌和真菌病原体的抗生素耐药性是对人类健康的主要威胁。 RR对于大多数两个组分系统的磷酸转移反应至关重要。我们对小的结合的研究 RRS分子可能会影响治疗剂的设计，以禁用关键的两组分系统 微生物病原体。我们项目的结果也可以用于预测或操纵信号 两个组件系统的动力学。信号转导的基本原理也可能出现。