Prion-based regulation of RNA-modifying enzyme activities

项目总结/摘要 朊病毒蛋白质在生物学上因导致致命的传染性脑部疾病而臭名昭著。 然而，除了疾病，朊病毒完全改变了我们对遗传的理解， 与它们的名声相反，它们不仅是致病因素。取而代之的是 在生命王国中都能找到，是一种影响一整套 细胞过程，也产生生物学上有益的性状。在本提案中，我们 专注于朊病毒，调节RNA，特别是RNA的朊病毒构象- 修饰酶这些高度保守的酶催化许多化学物质， RNA上的修饰对其结构和功能至关重要。我们的目标 研究的目的是了解这些酶的朊病毒样形式如何改变它们的活性 RNA上，产生基因表达的变化，并最终导致长期的， 可遗传的生长表型，如对环境胁迫的抗性。最近的一 我们已经详述这样的例子是假尿苷合酶的朊病毒原形式， 影响细胞增殖、衰老和蛋白质合成。这项工作使我们 研究其他RNA修饰酶具有朊病毒样行为的能力， 我们现在有几个新的例子可以研究。在这份提案中，我们将调查 当使它们接受朊病毒的酶时，RNA修饰是否发生了变化， 像构象一样，这些变化对基因表达的影响， 酶催化，感染性朊病毒蛋白的结构，以及朊病毒- 我们在芽殖酵母中观察到的基本行为在人类细胞中是保守的。我们 通过结合遗传学，高通量测序， 经典的生物化学方法和荧光显微镜。总之，这项工作的目的是 揭示了表观遗传的分子细节，朊病毒为基础的RNA调节， 细胞生长和存活。

Project Summary/Abstract Prion proteins are notorious in biology for causing deadly, infectious brain diseases. Beyond disease, however, prions completely altered our understanding of heredity, and contrary to their reputation, they are not only disease-causing agents. Instead, they are found across kingdoms of life, and are an epigenetic mechanism that affects a panoply of cellular processes, also producing biologically beneficial traits. In this proposal we focus on prions that regulate RNA, specifically, prionogenic conformations of RNA- modifying enzymes. These highly conserved enzymes catalyze numerous chemical modifications on RNA that are critical for their structure and function. The goal of our research is to understand how prion-like forms of these enzymes may alter their activities on RNA, producing changes to gene expression, and ultimately, leading to long-lasting, heritable growth phenotypes, such as resistance to environmental stress. One recent such example that we have detailed is a prionogenic form of a pseudouridine synthase, which affects cell proliferation, aging, and protein synthesis. This work led us to investigate the capacity for other RNA-modifying enzymes to have prion-like behavior, and we now have several new examples for study. In this proposal, we will investigate whether RNA modifications are changed when the enzymes that make them adopt prion- like conformations, the effects these changes have on gene expression, the role for enzyme catalysis, the structure of the infectious prion protein, and whether the prion- based behavior that we have observed in budding yeast is conserved in human cells. We approach these questions using a combination of genetics, high-throughput sequencing, classical biochemical methods, and fluorescence microscopy. In summary, this work aims to uncover the molecular details of epigenetic, prion-based regulation of RNA that affects cell growth and survival.