Coregulation of mRNA, tRNA, and rRNA species through RNA modifications

项目摘要 最近的研究表明，在细胞内部发现了多种酶介导的修饰 在RNA中，它显著影响RNA在细胞中的命运。大部分的RNA修饰 并通过酶除去，所述酶被称为writers（例如，甲基转移酶）和橡皮擦（例如，脱甲基酶）。 重要的是，迄今为止的研究仅集中在分离的RNA上的个体修饰。但最近的 来自我实验室和其他实验室的数据表明，修饰或修饰酶之间存在相互作用， 影响几种RNA修饰的沉积和结果。我们的初步数据显示 一种mRNA修饰的水平影响另一种mRNA修饰的水平，这表明mRNA 修饰可以以先前未确定的组合方式起作用。我们还发现， tRNA修饰的水平与mRNA修饰同时受到RNA复合物的调节， 修饰酶这些数据表明RNA修饰酶之间的协调。但 这些RNA修饰酶如何协调的详细机制和生物学功能， tRNA和mRNA中RNA修饰的相互作用是未知的。我们发现一种rRNA 甲基转移酶具有双重酶活性，并在rRNA和mRNA上安装二甲基化。虽然 rRNA甲基转移酶在体外对rRNA和mRNA同样有效， 在细胞中要低得多，这表明底物偏好受到调节。然而，不知道这是如何发生的。 控制rRNA甲基转移酶以实现底物选择性。为了研究一个组合的 m3C和m6A在mRNA中的相互作用。具体地说， 我们将研究m3C的沉积是否影响m6A，反之亦然。我们还将研究 组合mRNA修饰在修饰结合蛋白募集中的机制， RNA修饰酶的催化和底物的可及性。为了了解潜在的 通过RNA修饰，mRNA和tRNA之间的相关性，我们将研究相互作用和 Trmt 10A和YTHDF 2的蛋白质复合物的干扰相互作用的细胞后果。到 了解二甲基腺苷甲基转移酶如何调节rRNA和mRNA修饰，我们将 分别研究二甲基腺苷在rRNA和mRNA中的作用。然后研究 这种酶实现底物偏好的调节机制。这些创新的 这些研究将为了解多种类型的酶介导的RNA修饰 协同作用。

Project Summary It has been demonstrated recently that a diverse set of enzyme-mediated modifications are found internally within RNAs which markedly influence the fate of RNAs in cells. Most of the RNA modifications are installed and removed by enzymes, termed writers (e.g., methyltransferases) and erasers (e.g., demethylases). Importantly, studies to date have focused solely on individual modifications on isolated RNA. However, recent data from my laboratory and others’ suggest cross-talk between modifications or the modifying enzymes influence both the depositions and consequences of several RNA modifications. Our preliminary data suggest that the level of one type of mRNA modification influences the level of the other, indicating that mRNA modifications may function in a previously undetermined combinatorial fashion. We also discovered that the level of a tRNA modification is concurrently regulated with a mRNA modification by a complex of RNA modifying enzymes. These data suggest the coordination between RNA modifying enzymes. However, the detailed mechanism of how these RNA modifying enzymes are coordinated and the biological function of the interplay of RNA modifications in tRNA and mRNA is not known. We discovered that a rRNA methyltransferase has dual enzymatic activities and install di-methylation on both rRNA and mRNA. Although the rRNA methyltransferase works equally well on rRNA and mRNA in vitro, the levels of mRNA modification are much lower in cells, suggesting that substrate preference is regulated. However, it is not known how this rRNA methyltransferase is controlled to achieve the substrate selectivity. To study whether a combinatorial modification code exists in mRNA, we will study the interplay between m3C and m6A in mRNA. Specifically, we will investigate whether the deposition of m3C affects m6A, and vice versa. We will also study the possible mechanism of the combinatorial mRNA modification in the recruitment of modification binding proteins, catalysis of RNA modifying enzymes, and the accessibility of the substrate. To understand the potential correlation between mRNA and tRNA through RNA modifications, we will investigate the interactions and the cellular consequence of the disturbed interactions of a protein complex of Trmt10A and YTHDF2. To understand how a dimethyladenosine methyltransferase regulates rRNA and mRNA modification, we will investigate the functions of dimethyladenosine in rRNA and mRNA, respectively. And then to study the regulatory mechanism by which this enzyme achieves substrate preference. Collectively, these innovative studies will provide fundamental insights into how multiple types of enzyme-mediated RNA modifications synergistically function.