Regulation mechanisms of ABC transporters

ABC转运蛋白的调控机制

• 批准号: 10893186
• 负责人: Heather Wendy Pinkett
• 金额: $ 7.85万
• 依托单位: NORTHWESTERN UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-15 至 2025-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10893186
• 关键词: ATP-Binding Cassette Transporters; Adenosine Triphosphate; Antibiotics; Bacteria; Binding; Binding Proteins; Biochemical; Biochemistry; Biological Assay; Biological Models; Biophysics; Cell Survival; Cell membrane; Cell secretion; Cells; Classification Scheme; Complex; Core Assembly; Cues; Cytolysis; Cytoplasm; Data; Development; Ensure; Environment; Epithelial Cells; Family; Gatekeeping; Genes; Goals; Heme; Hydrolysis; Immune; Immune response; Infection; Iron; Laboratories; Length; Mediating; Membrane; Molecular; Molecular Conformation; Nickel; Nutrient; Organism; Peptides; Play; Positioning Attribute; Proteins; Reaction; Recycling; Regulation; Research; Research Personnel; Resistance development; Rice; Role; Site; Specificity; Structure; Sulfur; System; Testing; Toxic effect; Toxin; Virulence; Work; antimicrobial drug; antimicrobial peptide; cofactor; dimer; experimental study; insight; microbial; novel; pathogen; pathogenic bacteria; peptide structure; programs; recruit; sensor; structural biology; uptake

PROJECT SUMMARY This proposal seeks to understand how proteins located in the cell membrane work as gatekeepers to selectively allow compounds into or out of the cell. Such gatekeepers are known as or ATP-binding cassette (ABC) transporters, because they use the energy of ATP (adenosine triphosphate) hydrolysis to transport compounds across the cell membrane. Bacterial ABC importers are essential for organism survival, controlling the rate of uptake for nutrients scavenged from the bacterium's environment. Control of the rate of transport precludes over-accumulation of a nutrient that is beneficial at low concentrations, but is potentially toxic at high concentrations. While a subset of ABC proteins contain an additional “accessory” domain that can regulate the uptake of compounds by shutting off the transporter, it is unclear why certain transporters contain these domains while others do not. However, we do understand that certain transporters are “turned off” when a specific compound or protein binds to this accessory domain. Other accessory domains regulate by “sensing” changes in the microenvironment and reacting accordingly. To decipher this mechanism of regulation, the PI's laboratory combines biochemical and biophysical experiments with structural biology to understand how these accessory domains play a role in transport regulation, which in restricts or allows nutrients to enter the cell. This research program will define the molecular mechanism that controls nutrient uptake and allow researchers to understand how multiple transport systems work in concert within an organism to maintain cell survival. We will test our hypothesis that regulation of transporter activation via a sensing accessory protein. The proposed research will decipher the complex circuitry of regulation in a model system in three Aims to: (1) understand how PepT SBPs select for different substrates within the microenvironment (i.e., nutrients, cofactors and peptides); (2) determine how the assembly of the core transporter dictates transport selectivity and efficiency (3) reveal how PepT transporters regulate the import of substrates into the cell through the activation of a novel regulatory domain. This research program has set out to close critical gaps in the understanding of the fundamentals of the transport mechanism present in all bacteria. The results will yield insights into how regulatory domains modulate transport across all organisms, crucial for cell viability.

项目摘要 这项提议旨在了解位于细胞膜上的蛋白质如何作为守门人工作， 选择性地允许化合物进出细胞。这种看门人被称为或ATP结合 盒（ABC）转运蛋白，因为它们使用ATP（三磷酸腺苷）水解的能量 来运输化合物穿过细胞膜。细菌ABC进口商是必不可少的， 生物体的生存，控制从细菌的营养素清除的吸收率 环境控制运输速度可以防止营养物质的过度积累， 在低浓度下有益，但在高浓度下可能有毒。虽然ABC的子集 蛋白质含有额外的“辅助”结构域，其可以通过以下方式调节化合物的摄取： 关闭转运蛋白，目前还不清楚为什么某些转运蛋白含有这些结构域，而其他转运蛋白含有这些结构域。 不要。然而，我们确实理解，当特定的 化合物或蛋白质与该辅助结构域结合。其他附属结构域通过“感知”进行调节 微环境的变化，并做出相应的反应。为了解释这种调节机制， PI的实验室将生物化学和生物物理实验与结构生物学相结合， 了解这些附件域如何在运输调节中发挥作用， 允许营养物质进入细胞。这项研究计划将确定分子机制， 控制营养吸收，并使研究人员了解多种运输系统如何工作， 在有机体内协调一致以维持细胞存活。我们将检验我们的假设， 通过传感辅助蛋白激活转运蛋白。拟议中的研究将破译 在一个模型系统中的复杂的调节电路有三个目的：（1）了解PepT SBPs如何 选择微环境中的不同基质（即，营养素、辅因子和肽）;（2） 确定核心转运蛋白的组装如何决定转运选择性和效率（3） 揭示了PepT转运蛋白如何通过激活细胞内的蛋白质来调节底物进入细胞。 新的调节域。这项研究计划已经开始缩小在理解方面的关键差距， 所有细菌的运输机制的基本原理。结果将产生见解 调节域如何调节所有生物体的运输，这对细胞活力至关重要。