Amino acid mimicry: Insights into glyphosate transport and toxicity to mitochondria

氨基酸拟态：深入了解草甘膦转运和线粒体毒性

• 批准号: 10573869
• 负责人: Jennifer Gallagher
• 金额: $ 7.6万
• 依托单位: WEST VIRGINIA UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-02-10 至 2025-01-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10573869
• 关键词: Acute; Affect; Amino Acids; Animals; Aromatic Amino Acids; Aspartate; Bacteria; Binding; Binding Proteins; Biochemical; Brain; Bypass; Cell Cycle; Cells; Chemical Exposure; Cytoplasm; DNA Damage; Data; Data Set; Diet; Disease; Down-Regulation; Enzymes; Evolution; Food Chain; Food Contamination; Formulation; Future; Genes; Genetic; Glutamate Transporter; Glutamates; Goals; Growth; Health; Herbicides; Human; Human Development; Malate-Aspartate Shuttle Pathway; Malates; Measures; Metabolic Diseases; Metabolism; Mitochondria; Mitochondrial Proteins; Modeling; NADH; Nutrient; Nutrient availability; Occupational Exposure; Organ; Organism; Pathway interactions; Penetration; Plants; Preparation; Regulation; Repression; Reproduction; Research; Resistance; Role; Saccharomyces cerevisiae; Site; Structure; Supplementation; Testing; Time; Tissues; Toxic effect; Transportation; Urine; Yeasts; cancer type; experimental study; exposed human population; fungus; genome wide association study; glyphosate; gut microbiome; innovation; insight; mimicry; mitochondrial metabolism; model organism; mutant; nervous system disorder; permease; sensor; shikimate; surfactant; transcriptomics

Extensive use of glyphosate-based herbicides (GBH) has led to glyphosate entering the food chain, and causing human sera and urine levels to increase over time. This exposure has led to numerous claims that glyphosate causes diseases ranging from multiple types of cancer to affecting human development and reproduction. However, no mechanism of glyphosate import into human cells is known; in yeast, importation occurs through the glutamate/ aspartate (D/E) transporters due to its structural resemblance. Glyphosate is thought not to have acute effects on humans because they lack the shikimate pathway that produces aromatic amino acids (WYF), which is inhibited in the presence of glyphosate, and humans instead acquire aromatic amino acids through diet or the gut microbiome. The differences in commercial preparations of glyphosate have complicated the studies because GBHs have surfactants that increase tissue penetration. Yeast can bypass the inhibition of the shikimate pathway when supplemented with (WYF), which permits the assessment of the role of surfactants or, more likely, discover the unknown glyphosate targets. Our initial studies have found that genes regulating mitochondria, DNA damage, and the cell cycle are differentially regulated in GBH treatments. The long-term goal is to identify the glyphosate transportation mechanisms into cells, the brain, and other tissues that affect mitochondrial metabolism. This application's objective is to determine how mitochondrial metabolism is affected by glyphosate alone and in commercial formulations in the model organism S. cerevisiae. Our central hypothesis is that the transport of glyphosate is due to mimicry of glutamate and aspartate; thus, it will affect other enzymes that utilize glutamate and aspartate, especially within the mitochondria. The rationale of this proposal is that mitochondrial effects of glyphosate have a biochemical basis and will provide a mechanistic understanding of cellular effects in vertebrate species. Specific aims proposed are 1. Measure the import of glyphosate into different compartments in different mutants and how adding D/E rescues growth inhibition from glyphosate 2. Measure changes in specific mitochondrial metabolites (ATP and NADH) in glyphosate treated cells. The proposed research is innovative because the hypothesis proposed is using unbiased experiments, such as genome-wide association, transcriptomics, and In-Lab Evolution experiments to determine the mechanism of extra- and intracellular glyphosate transport using D/E transporters. Glyphosate mimics D/E amino acids in transport, so it likely affects other enzymes that use D/E, particularly in the mitochondria. In plants, fungi, and bacteria, D/E transporters have all been implicated in glyphosate transport and glyphosate affecting mitochondrial functions. While humans do not have the shikimate pathway, they have D/E transporters, and conserved mitochondrial proteins that use D/E, which may be the off-targets of glyphosate leading to the range of diseases claimed to have been caused by glyphosate.

草甘膦除草剂（GBH）的广泛使用导致草甘膦进入食物链， 导致人类血清和尿液中的浓度随时间增加。这一曝光导致了许多人声称， 草甘膦会导致多种疾病，从多种癌症到影响人类发育， 生殖然而，草甘膦输入到人类细胞中的机制尚不清楚;在酵母中， 由于其结构相似，通过谷氨酸/天冬氨酸（D/E）转运蛋白发生。草甘膦是 认为对人类没有急性影响，因为它们缺乏产生芳香族化合物的莽草酸途径。 氨基酸（WYF），这是抑制草甘膦的存在，而人类反而获得芳香族 氨基酸通过饮食或肠道微生物组。草甘膦商业制剂的差异 使研究复杂化，因为GBH含有增加组织渗透的表面活性剂。酵母可以 当补充（WYF）时，绕过莽草酸途径的抑制，这允许评估 表面活性剂的作用，或者更有可能的是，发现未知的草甘膦目标。我们的初步研究 发现GBH中调节线粒体、DNA损伤和细胞周期的基因受到不同的调节 治疗。长期目标是确定草甘膦进入细胞，大脑， 以及其他影响线粒体代谢的组织。本应用程序的目标是确定如何 模型中，线粒体代谢受草甘膦单独和商业制剂的影响 有机体S.啤酒。我们的中心假设是，草甘膦的运输是由于模仿 谷氨酸和天冬氨酸;因此，它会影响其他利用谷氨酸和天冬氨酸的酶， 在线粒体内。这一建议的基本原理是，草甘膦的线粒体效应具有 生物化学的基础上，并将提供在脊椎动物物种的细胞效应的机制的理解。 具体目标是1。测量草甘膦在不同区域进入不同隔室的情况 突变体以及添加D/E如何挽救草甘膦2的生长抑制。衡量具体 线粒体代谢物（ATP和NADH）在草甘膦处理的细胞。该研究具有创新性 因为提出的假设是使用无偏实验，如全基因组关联， 转录组学和实验室进化实验，以确定细胞外和细胞内的机制， 使用D/E转运蛋白转运草甘膦。甘氨酸在运输中模拟D/E氨基酸，因此它可能 影响其他使用D/E的酶，特别是在线粒体中。在植物、真菌和细菌中，D/E 转运蛋白都与草甘膦转运和影响线粒体功能的草甘膦有关。 虽然人类没有莽草酸途径，但他们有D/E转运蛋白和保守的线粒体 使用D/E的蛋白质，这可能是草甘膦的脱靶点，导致一系列疾病， 是由草甘膦引起的