The Role of m6A-RNA Methylation in Memory Formation and Recall and Its Modulation and Influence on Long-Term Outcomes as a Consequence of Early Life Lead Exposure.

m6A-RNA 甲基化在记忆形成和回忆中的作用及其对早期铅暴露后果的长期结果的调节和影响。

• 批准号: 9927737
• 负责人: JAY S SCHNEIDER
• 金额: $ 16.41万
• 依托单位: THOMAS JEFFERSON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-06-15 至 2021-06-14
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9927737
• 关键词: Address; Adenosine; Adverse effects; Affect; Animal Model; Animals; Auditory; Basic Science; Behavioral; Brain; Brain region; Bypass; Chemicals; Child; Cognitive; Cues; DNA; DNA Methylation; Data; Development; Dimensions; Disease; Epigenetic Process; Fatty acid glycerol esters; Female; Functional disorder; Gene Expression; Gene Expression Regulation; Genes; Genetic Transcription; Goals; Health; Hippocampus (Brain); Impaired cognition; Impairment; Lead; Life; Maintenance; Maps; Memory; Memory impairment; Messenger RNA; Methylation; Methyltransferase; Modification; Molecular; Mus; Neuronal Plasticity; Neurotoxins; Obesity; Outcome; Pathologic; Pathway interactions; Performance; Play; Post-Transcriptional Regulation; Prefrontal Cortex; Promoter Regions; Public Health; Publishing; RNA; RNA immunoprecipitation sequencing; RNA methylation; Rattus; Regulatory Pathway; Reporting; Research; Role; Site; Testing; Training; Transcript; Transcriptional Regulation; Translations; Work; adverse outcome; base; behavioral plasticity; behavioral response; brain behavior; conditioned fear; epitranscriptome; epitranscriptomics; experience; gene environment interaction; genetic regulatory protein; genome wide methylation; histone modification; improved; insight; knock-down; lead exposure; lentiviral-mediated; male; memory encoding; memory process; nervous system development; neurotoxicology; novel; promoter; response; sex; transcriptome

Regulation of transcription is central to proper nervous system development and functioning. Dysregulation of transcriptional and post-transcriptional regulatory pathways are associated with various neurodevelopmental diseases and disorders including developmental lead (Pb) exposure, which is associated with significant and persistent cognitive and behavioral deficits. Recent data from our lab have shown Pb-induced methylation changes at gene promoter regions and effects of Pb on various post-translational histone modifications (PTHMs), however, gene expression changes have not always corresponded to promoter methylation status and mismatches between PTHM levels and transcriptional regulation were also observed, suggesting that other factors may be influencing transcriptional changes in response to Pb exposures. Thus, mechanisms un- derlying altered transcriptional regulation in specific brain regions following Pb exposure cannot be completely explained by alterations in DNA methylation and PTHM levels. Preliminary data from our lab support the hy- pothesis that another mechanism, direct RNA methylation via N6-methyladenosine (m6A), may be an important post-transcriptional mechanism contributing to the functionally altered transcriptome after developmental Pb exposure. Like DNA, RNA is susceptible to dynamic, reversible chemical modification and this epitranscrip- tomic mechanism may play an important role in gene transcription and behavioral plasticity. This has not been investigated as a potential molecular mechanism involved in environmental neurotoxicology. The goal of this proposal is to test the novel hypothesis that the most abundant epitranscriptomic mark, m6A, plays an im- portant role in modulating RNA and influencing memory processes in male and female rats and, based on preliminary data, in regulating transcriptional and behavioral responses to developmental Pb exposure. The following aims will examine the contribution of m6A to memory processing in normal and Pb-exposed animals: Aim1: Examine transcriptome-wide profile of the m6A modification (using methylated RNA immunoprecipitation sequencing (MeRIP-seq)) in mPFC and hippocampus (CA1) in behaviorally naïve and behaviorally trained ani- mals of both sexes to assess its potential role as a dynamic epitranscriptomic mechanism involved in encoding and maintenance of memory, and, examine the extent to which the transcriptome-wide m6A enrichment profile is altered in animals with developmental Pb exposure; Aim2: Assess the functional significance of m6A in PFC and CA1 in memory processes in Pb-exposed animals using site-directed knockdown of the RNA demethylase gene, Fto, which will increase m6A levels in mPFC and CA1 and allow us to evaluate the effects of brain region -dependent reversal of decreased m6A levels on Pb-induced impaired memory processes. This work, the first to examine the dynamic modulation of RNA by m6A in PFC and CA1 in male and female normal and Pb- exposed rats, will result in new information regarding mRNA methylation as an effector mechanism for gene expression and behavioral plasticity in response to an environmental neurotoxicant.

转录调节对于神经系统的正常发育和功能失调至关重要。 转录和转录后调节途径与各种神经发育相关 疾病和失调，包括发育性铅（Pb）暴露，这与显着和 我们实验室的最新数据显示铅诱导的甲基化。 基因启动子区域的变化以及 Pb 对各种翻译后组蛋白修饰的影响 （PTHM），然而，基因表达变化并不总是与启动子甲基化状态相对应 还观察到 PTHM 水平和转录调控之间的不匹配，这表明 其他因素可能会影响铅暴露引起的转录变化。 铅暴露后特定大脑区域转录调控的改变不能完全被 我们实验室的初步数据支持了这一点。 假设另一种机制，即通过 N6-甲基腺苷 (m6A) 直接进行 RNA 甲基化，可能是一个重要的机制。 转录后机制导致发育Pb后转录组的功能改变 与 DNA 一样，RNA 也容易受到动态、可逆的化学修饰，并且这种外转录- tomic机制可能在基因转录和行为可塑性中发挥重要作用，但这一点尚未得到证实。 作为环境神经毒理学中潜在的分子机制进行研究。 该提案的目的是检验最丰富的表观转录组标记 m6A 发挥重要作用的新假设。 在调节 RNA 和影响雄性和雌性大鼠的记忆过程中发挥重要作用，并且基于 初步数据，调节发育铅暴露的转录和行为反应。 以下目标将检查 m6A 对正常和铅暴露动物的记忆处理的贡献： 目标 1：检查 m6A 修饰的全转录组谱（使用甲基化 RNA 免疫沉淀 对行为幼稚者和经过行为训练的动物的 mPFC 和海马体 (CA1) 进行测序 (MeRIP-seq) 两性的 Mals 评估其作为参与编码的动态表观转录组机制的潜在作用 和记忆的维持，并检查全转录组 m6A 富集谱的程度 在发育过程中暴露于铅的动物中发生改变；目标 2：评估 m6A 在 PFC 中的功能意义 和 CA1 在铅暴露动物的记忆过程中使用 RNA 去甲基酶的定点敲低 基因 Fto，它将增加 mPFC 和 CA1 中的 m6A 水平，使我们能够评估大脑区域的影响 依赖于 Pb 诱导的记忆过程受损的 m6A 水平降低的逆转。 检测男性和女性正常和 Pb- 中 PFC 和 CA1 中 m6A 对 RNA 的动态调节 暴露的大鼠，将产生关于 mRNA 甲基化作为基因效应机制的新信息 对环境神经毒物的表达和行为可塑性。