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

项目摘要 最近已经证明，在体内发现了一系列不同的酶介导的修饰 在RNA中，它显著地影响细胞中RNA的命运。大多数RNA修改都已安装 并被称为写入物(例如甲基转移酶)和擦除器(例如去甲基酶)的酶去除。 重要的是，到目前为止，研究仅仅集中在对分离的RNA的个别修饰上。然而，最近 来自我的实验室和其他人的数据表明，修饰或修饰酶之间存在串扰 影响几种RNA修饰的证据和后果。我们的初步数据显示 一种类型的信使核糖核酸修饰水平会影响另一种信使核糖核酸的水平，这表明信使核糖核酸 修饰可以以先前未确定的组合方式起作用。我们还发现， 通过RNA复合体同时调节tRNA修饰和mRNA修饰的水平 修饰酶。这些数据表明了RNA修饰酶之间的协调。然而， 这些RNA修饰酶如何协调的详细机制以及该酶的生物学功能 RNA修饰在tRNA和mRNA中的相互作用尚不清楚。我们发现一种rRNA 甲基转移酶具有双重的酶活性，在rRNA和mRNA上都有二甲基化作用。虽然 Rrna甲基转移酶在体外对rrna和mrna同样有效，在mrna修饰水平上。 在细胞中要低得多，这表明底物偏好受到调控。然而，目前还不知道这是如何实现的 通过控制rRNA甲基转移酶来实现底物选择性。来研究一个组合是否 M RNA中存在修饰密码，我们将研究m 3c和m 6A在m RNA中的相互作用。具体来说， 我们将调查M3C的沉积是否影响M6A，反之亦然。我们还将研究可能的 组合mRNA修饰在修饰结合蛋白募集中的作用机制 RNA修饰酶的催化作用，以及底物的可及性。要了解潜在的 通过RNA修饰，我们将研究它们之间的相互作用和相互作用 Trmt10A和YTHDF2蛋白复合体相互作用紊乱的细胞后果。至 了解二甲基腺苷甲基转移酶是如何调节rRNA和mrna修饰的，我们将 分别研究二甲基腺苷在rRNA和mRNA中的作用。然后再研究一下 该酶实现底物偏好的调节机制。总体而言，这些创新的 研究将为多种类型的酶介导的RNA修饰提供基本的见解 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.