m6A mRNA reader proteins in the AIDS-opportunistic pathogen Toxoplasma gondii

弓形虫是一种细胞内寄生虫，可引起危及生命的机会性感染。 在艾滋病毒/艾滋病患者中。复制阶段(速殖子)发展为潜伏期(缓殖子)。 这不受豁免权和经批准的抗寄生虫药物的影响。组织囊肿会引起 在免疫功能受损的人中反复激活感染，在 艾滋病毒/艾滋病患者。使这个问题变得更加复杂的是缺乏安全有效的治疗方法， 这强调了迫切需要确定寄生虫中可能存在的 被用来开发更好的药物。我们和其他人最近发现 在弓形虫mRNA中，6位腺苷(M6A)甲基化丰富，代表 一层新的基因调控被称为表位转录组学。重要的是，“写”的蛋白质 而“读”m6A基因的修饰对于寄生虫的生存至关重要。此外，由于这台机器 它更像植物而不是人类，它代表了一个有吸引力的新药靶点。研究这一点 弓形虫的脆弱性，我们的目标是填补我们关于这一信号如何产生的知识空白 通过对m6A阅读器蛋白的研究，决定了mRNA转录本的命运。我们假设 弓形虫m6A信使核糖核酸阅读器蛋白协调信使核糖核酸代谢的各个方面 对寄生虫的生存至关重要。在其他物种中，m6A阅读器位于细胞核和 胞浆，通过调节剪接、运输和翻译来调节信使核糖核酸的命运。到目前为止， 只有两个核心的YTH家族M6A阅读器已被确认，而且他们基本上仍然存在 没有特征的。而且，尽管胞浆中有丰富的m6A mRNA，但胞浆中没有m6A 读者身份已经确定。我们提出了两个具体目标，将通过以下方式解决我们的假设 回答这些问题。目标1将确定两个植物样Yth M6A的作用 在弓形虫细胞核内工作的读者。AIM 2将鉴定新的m6A阅读器蛋白 使用我们开发的功能性M6A结合探针检测速殖子和缓殖子。这些 开创性的研究将标志着对m6A读者的第一次详细分析，包括复制和 弓形虫的潜伏期，有望揭示治疗这种疾病的新的治疗选择 HIV/AIDS患者的机会性感染。

Toxoplasma gondii is an intracellular parasite that causes life-threatening opportunistic infection in HIV/AIDS patients. The replicative stage (tachyzoite) develops into a latent stage (bradyzoite) that is impervious to immunity and approved antiparasitic drugs. Tissue cysts give rise to recurrent reactivation of infection in the immunocompromised, creating chronic disease in HIV/AIDS patients. Compounding this problem is a paucity of safe and effective therapies, which underscores the urgent need to identify essential processes in the parasite that could be exploited for the development of better drugs. We and others recently discovered that methylation of adenosines at position 6 (m6A) is abundant in Toxoplasma mRNA, representing a new layer of gene regulation called epitranscriptomics. Importantly, the proteins that “write” and “read” m6A modifications are essential for parasite viability. Moreover, as this machinery resembles plants more than humans, it represents an attractive new drug target. To study this vulnerability in Toxoplasma, we aim to fill the gap in our knowledge regarding how this signal dictates the fate of mRNA transcripts through the study of m6A reader proteins. We hypothesize that Toxoplasma m6A mRNA reader proteins coordinate different aspects of mRNA metabolism essential for parasite viability. In other species, m6A readers are found in the nucleus and cytosol, regulating the fate of mRNA by modulating splicing, trafficking, and translation. To date, only two nuclear YTH family m6A readers have been identified and they remain largely uncharacterized. And, despite the abundance of m6A mRNA in the cytosol, no cytosolic m6A readers have been identified. We propose two specific aims that will address our hypothesis by answering these questions. Aim 1 will determine the roles of the two plant-like YTH m6A readers operating in the Toxoplasma nucleus. Aim 2 will identify novel m6A reader proteins from tachyzoites and bradyzoites using a functional m6A-binding probe that we developed. These pioneering studies will mark the first detailed analysis of m6A readers in both replicative and latent stages of Toxoplasma, which promises to reveal new therapeutic options to treat this opportunistic infection of HIV/AIDS patients.