Regulation mechanisms of ABC transporters

ABC转运蛋白的调控机制

• 批准号: 10478032
• 负责人: Heather Wendy Pinkett
• 金额: $ 31.07万
• 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/10478032
• 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; 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; Recycling; Regulation; Research; Research Personnel; Resistance development; Rice; Role; Site; Specificity; Structure; Sulfur; System; Testing; Toxic effect; Toxin; Virulence; Work; antimicrobial drug; antimicrobial peptide; base; cofactor; dimer; experimental study; insight; microbial; novel; pathogen; pathogenic bacteria; 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.

项目概要 该提案旨在了解位于细胞膜中的蛋白质如何充当守门人 选择性地允许化合物进入或离开细胞，这种看门人被称为 ATP 结合。 盒式 (ABC) 转运蛋白，因为它们利用 ATP（三磷酸腺苷）水解的能量 细菌 ABC 输入蛋白对于跨细胞膜转运化合物至关重要。 生物体的生存，控制从细菌中清除的营养物质的吸收率 控制运输速率可防止营养物质过度积累。 低浓度时有益，但高浓度时有潜在毒性，而 ABC 的一个子集。 蛋白质含有一个额外的“辅助”结构域，可以调节化合物对化合物的吸收 关闭传输器，目前还不清楚为什么某些传输器包含这些域，而其他传输器则包含这些域 然而，我们确实知道某些传输器在特定情况下会“关闭”。 化合物或蛋白质与该辅助结构域结合，通过“传感”进行调节。 为了破译这种调节机制， 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 了解这些辅助域如何在运输监管中发挥作用，从而限制或 该研究项目将定义允许营养物质进入细胞的分子机制。 控制营养吸收并让研究人员了解多种运输系统如何工作 我们将检验我们的假设，即生物体内的调节。 拟议的研究将通过传感辅助蛋白激活转运蛋白。 模型系统中的复杂调节电路有三个目的：(1) 了解 PepT SBP 如何 选择微环境中的不同底物（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 PepT 转运蛋白如何通过激活 该研究计划旨在弥合理解方面的关键差距。 所有细菌中存在的转运机制的基本原理的研究结果将产生深入的见解。 研究调控域如何调节所有生物体的运输，这对细胞活力至关重要。