Epitranscriptomics in the AIDS-opportunistic pathogen Toxoplasma gondii

艾滋病机会致病菌弓形虫的表观转录组学

• 批准号: 9889878
• 负责人: William J Sullivan
• 金额: $ 23.28万
• 依托单位: INDIANA UNIV-PURDUE UNIV AT INDIANAPOLIS
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-03-08 至 2022-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9889878
• 关键词: 4-thiouracil; 5' Untranslated Regions; AIDS/HIV problem; Acquired Immunodeficiency Syndrome; Address; Adenosine; Affect; Antiparasitic Agents; Area; Automobile Driving; Brain; Cells; Cellular Stress; Chronic; Chronic Disease; Clinical; Communities; Complex; Congenital Abnormality; Cyst; Data Set; Development; Epigenetic Process; Eukaryotic Initiation Factor-2; Felis catus; Follow-Up Studies; Food Contamination; Future; Gene Expression; Gene Expression Regulation; Genetic Transcription; Heat-Shock Response; Homologous Gene; Human; Immune response; Immunity; Immunocompromised Host; Immunoprecipitation; In Vitro; Individual; Infection; Investigation; Label; Life; Link; Location; Lytic Phase; Messenger RNA; Methylation; Modification; Molecular; Multienzyme Complexes; Muscle; Myocardium; Nuclear; Nucleotides; Opportunistic Infections; Parasites; Pathogenesis; Patients; Pharmaceutical Preparations; Phosphorylation; Physiologic pulse; Population; Positioning Attribute; Post-Transcriptional Regulation; Process; Proliferating; Proteins; RNA; RNA Processing; RNA Splicing; Reagent; Recurrence; Refractory; Regulation; Research; Resolution; Role; Site; Skeletal Muscle; Stress; Therapeutic Intervention; Tissues; Toxoplasma; Toxoplasma gondii; Toxoplasmosis; Transcript; Translations; Water; clinically relevant; crosslink; epitranscriptome; epitranscriptomics; insight; knock-down; pathogen; polysome profiling; protein complex; response; transcription factor; transcriptome; transcriptome sequencing

Toxoplasma gondii is an intracellular parasite that has infected up to one-third of the population. The pathogen can cause congenital birth defects and life-threatening opportunistic infection in HIV/AIDS. The replicative stage (tachyzoite) develops into a latent stage (bradyzoite) that resides inside brain, heart, and skeletal muscle tissues, and is impervious to immunity and currently approved antiparasitic drugs. Tissue cysts give rise to recurrent reactivation of infection in immunocompromised patients, creating chronic disease in HIV/AIDS patients. Despite its clinical importance, we know very little about the molecular details orchestrating the conversion between tachyzoites and bradyzoites. Studies have revealed that the development of bradyzoites, which can be triggered in vitro by cellular stress, is a complex process subject to regulation at transcriptional and post-transcriptional levels. Recently, it has been shown in other species that mRNA modifications, specifically post-transcriptional methylation of adenosines at position 6 (m6A), influence gene expression by altering RNA processing or translation. Changes in m6A marks have been associated with modulating cellular stress, development, and differentiation. The discovery of m6A represents a new layer of gene regulation called epitranscriptomics that has not been investigated in protozoan parasites. In preliminary studies, we establish that Toxoplasma RNA is subject to m6A, and we have begun characterizing the enzyme complex that delivers this RNA modification. The study of m6A in Toxoplasma in the context of HIV/AIDS is significant as this modification has been linked to stress-induced changes in cells, making it highly likely that m6A participates in bradyzoite development. In this new R21, we will address our hypothesis that m6A mRNA modifications are required for tachyzoite differentiation into bradyzoites by identifying changes in the m6A epitranscriptome during stage conversion (Aim 1) and determining the “writer” protein complex that delivers m6A onto Toxoplasma mRNA (Aim 2). Our proposed studies will be the first analysis of m6A on mRNA in parasites, and will generate valuable datasets and reagents needed to interrogate this vital new area of investigation relevant to the development of the tissue cysts, which give rise to chronic toxoplasmosis in HIV/AIDS patients.

弓形虫是一种细胞内寄生虫，已感染多达三分之一的人口。 可导致先天性出生缺陷和危及生命的艾滋病毒/艾滋病机会性感染。 阶段（速殖子）发展成潜伏阶段（缓殖子），存在于大脑、心脏和骨骼肌内 组织，并且不受免疫影响，目前批准的抗寄生虫药物会产生组织包囊。 免疫功能低下患者反复感染，造成艾滋病毒/艾滋病慢性病 尽管它具有临床重要性，但我们对协调这一过程的分子细节知之甚少。 研究表明，速殖子和缓殖子之间的转化。 它可以在体外由细胞应激触发，是一个受转录调控的复杂过程 最近，其他物种的 mRNA 修饰已被证明， 特别是 6 位腺苷 (m6A) 的转录后甲基化，通过以下方式影响基因表达 m6A 标记的改变与调节细胞有关。 m6A 的发现代表了基因调控的新层面。 在初步研究中，我们尚未在原生动物寄生虫中进行过研究。 确定弓形虫 RNA 受 m6A 影响，并且我们已经开始表征酶复合物 这种 RNA 修饰在艾滋病毒/艾滋病背景下对弓形虫中 m6A 的研究具有重要意义。 这种修饰与压力诱导的细胞变化有关，因此 m6A 很可能 在这个新的 R21 中，我们将解决 m6A mRNA 的假设。 通过识别 m6A 的变化，需要进行修饰以将速殖子分化为缓殖子 阶段转换期间的表观转录组（目标 1）并确定提供的“书写者”蛋白质复合物 m6A 到弓形虫 mRNA 上（目标 2）。我们提出的研究将是 m6A 对 mRNA 的首次分析。 寄生虫，并将生成研究这一重要新领域所需的有价值的数据集和试剂 与组织囊肿的发展相关的调查，组织囊肿会导致慢性弓形虫病 艾滋病毒/艾滋病患者。