tRNA modification reprogramming in artemisinin-resistant Plasmodium falciparum: An epigenetic driver of resistance?

抗青蒿素恶性疟原虫中的 tRNA 修饰重编程：耐药性的表观遗传驱动因素？

• 批准号: 10404060
• 负责人: Jennifer L. Small-Saunders
• 金额: $ 19.22万
• 依托单位: COLUMBIA UNIVERSITY HEALTH SCIENCES
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2025-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10404060
• 关键词: Acetylation; Acetyltransferase; Africa; Amino Acyl Transfer RNA; Aminoacyl-tRNA hydrolase; Artemisinins; Asia; Biology; Biomedical Research; Blood; Cellular Stress; Codon Nucleotides; Collection; Communicable Diseases; Complex; Coupled; Data; Development; Dimethyl Sulfoxide; Doctor of Philosophy; Drug resistance; Endocytosis; Engineering; Environment; Enzymes; Epigenetic Process; Eukaryota; Exposure to; Genes; Genetic; Genetic Transcription; Hemoglobin; Immunology; Kinetics; Laboratories; Lead; Liquid Chromatography; Malaria; Mass Spectrum Analysis; Mediating; Medical center; Medicine; Mentors; Metabolic; Microbiology; Modification; Molecular; Mutation; Nutritional; Parasite resistance; Parasites; Parasitology; Pathway interactions; Patient Care; Pharmaceutical Preparations; Physicians; Physiologic pulse; Plasmodium falciparum; Play; Positioning Attribute; Process; Prokaryotic Cells; Proteins; Proteome; Proteomics; RNA; Reaction Time; Reproducibility; Research; Resistance; Resistance development; Ribosomes; Role; Sampling; Scientist; Secondary to; South America; Stress; System; Techniques; Testing; Time; Training; Transcriptional Regulation; Transfer RNA; Translational Regulation; Translations; Universities; Up-Regulation; Variant; asexual; base; biological adaptation to stress; career; environmental enrichment for laboratory animals; epigenetic regulation; experimental study; genetic approach; innovation; insight; knock-down; multidisciplinary; multiple omics; mutant; pressure; resistant Plasmodium falciparum; response; sensor; tandem mass spectrometry; tool; transcriptome sequencing; translational proteomics

PROJECT SUMMARY / ABSTRACT: Rationale: The spread of artemisinin (ART)-resistant Plasmodium falciparum (Pf) strains across Asia and their recent emergence in Africa and South America imperils efforts to treat and control malaria. ART resistance is mediated primarily by mutations in Pf K13, which reduce drug activation by decreasing hemoglobin endocytosis and which initiate quiescence during peak drug levels. Our preliminary data have uncovered a role for tRNA modification reprogramming and proteomic changes in mutant K13 parasites exposed to ART pressure. In this mentored career project, we hypothesize that quiescence is epigenetically regulated by reprogramming tRNA modifications, which leverage codon-biased translation to alter the parasite proteome and enable the survival of ART-treated mutant K13 parasites. Candidate: As an Infectious Diseases physician with a PhD in Microbiology and Immunology, I am uniquely positioned to bridge biomedical research and patient care to understand the molecular mechanisms that Pf employs to survive ART treatment. Further training in molecular parasitology, mass spectrometry, proteomics, RNA biology, and epigenetics will be crucial for my development into an independent academic physician-scientist specializing in Pf stress responses and drug resistance. I have a renowned mentor in Dr. David Fidock and benefit from an outstanding multi- disciplinary team of experts to guide my training and research progress. Environment: The Fidock laboratory at the Columbia University Irving Medical Center (CUIMC) has been a pioneer in applying genetic and multi-omic tools to explore Pf resistance to ART and other drugs. This enriching environment also provides access to multiple isogenic k13-edited Pf lines and a large network of collaborators including experts in mass spectrometry- based tRNA modifications, proteomics, and codon-biased translation. CUIMC also has a long track record of enabling young physician-scientists to develop independent and successful careers in academic medicine. Approach: Our central hypothesis is that tRNA modification reprogramming, specifically the s2U modification, is central to how parasites achieve ART resistance by altering their proteome and regulating entry into and exit from drug-induced quiescence. In Aim 1, we will elucidate the kinetics of tRNA modification reprogramming in isogenic ART-resistant and ART-sensitive parasites across a panel of K13 variants and genetic backgrounds. In Aim 2, we will apply conditional knockdown approaches to explore the role of the s2U pathway in ART resistance and parasite survival. In Aim 3, we will test the complementary hypothesis that modifications on the amino-acyl tRNA regulate ART-mediated quiescence. This proposal provides an innovative approach to examining how K13 mutations achieve ART resistance via epigenetic changes that reprogram tRNA modifications to alter translational and proteomic responses to ART pressure. If confirmed experimentally, these hypotheses will set a new paradigm for how Pf can modulate its biology to survive drug-mediated cellular stress. Our results should also identify parasite vulnerabilities that can be leveraged into new strategies to treat ART-resistant malaria.

项目摘要/摘要：基本原理：抗青蒿素(抗逆转录病毒药物)疟原虫的传播 亚洲各地的恶性疟原虫(PF)菌株及其最近在非洲和南美洲的出现危及到 治疗和控制疟疾。ART耐药性主要由PfK13基因突变介导，该基因突变会减少药物 通过减少血红蛋白的内吞作用而激活，并在药物峰值时启动静息。我们的 初步数据揭示了tRNA修饰、重编程和蛋白质组变化在突变体中的作用 暴露于ART压力下的K13寄生虫。在这个有指导的职业项目中，我们假设静默是 通过重新编程tRNA修饰来表观遗传调节，利用偏向密码子的翻译来改变 寄生虫蛋白质组，并使经ART处理的突变K13寄生虫存活。应聘者：作为传染病患者 拥有微生物学和免疫学博士学位的疾病内科医生，我在生物医学方面具有独特的地位 研究和病人护理，以了解PF用于生存ART治疗的分子机制。 分子寄生虫学、质谱学、蛋白质组学、核糖核酸生物学和表观遗传学方面的进一步培训将 对我成长为一名独立的学术内科医生兼科学家来说至关重要，专门研究PF应激反应 以及抗药性。我有一位著名的导师大卫·菲多克博士，并受益于一位杰出的 学科专家团队指导我的培训和研究进展。环境：Fidock实验室位于 哥伦比亚大学欧文医学中心(CUIMC)是应用遗传学和多基因组技术的先驱 探索PF对抗逆转录病毒药物和其他药物耐药性的工具。这种丰富的环境还提供了访问 多个同基因K13编辑的PF系和包括质谱学专家在内的大型合作者网络- 基于tRNA修饰、蛋白质组学和偏向密码子的翻译。CUIMC还拥有长期的记录， 使年轻的内科科学家能够在学术医学领域发展独立和成功的职业生涯。 方法：我们的中心假设是tRNA修饰重编程，特别是s2U修饰，是 寄生虫如何通过改变其蛋白质组和调节进出来实现抗逆转录病毒治疗的核心 从药物诱导的静默中恢复。在目标1中，我们将阐明tRNA修饰重编程的动力学。 耐ART和ART敏感的同基因寄生虫分布在一组K13变异体和遗传背景中。在……里面 目的2，我们将应用条件性基因敲除方法来探讨s2u通路在抗逆转录病毒治疗中的作用。 以及寄生虫的存活。在目标3中，我们将检验互补假设，即对氨基酰基的修饰 TRNA调节ART介导的静止。该提案提供了一种创新的方法来研究K13如何 突变通过重新编程tRNA修饰以改变的表观遗传变化来实现ART抗性 翻译和蛋白质组对ART压力的反应。如果在实验上得到证实，这些假设将 一个关于PF如何调节其生物学以在药物介导的细胞压力下生存的新范例。我们的结果应该是 还要确定可用于治疗抗逆转录病毒疟疾的新战略的寄生虫脆弱性。