Recognition and mechanism of N6-methyl adenosine modifications

N6-甲基腺苷(M6A)是信使和长非核糖体中含量最丰富的内部修饰。 编码RNA。这种修饰发生在mRNA的许多位点上，其拟议的功能包括 剪接、输出、细胞质定位、稳定性、翻译活性和免疫耐受。功能性 自2011年以来，由于我们发现了人类，对M6A基因修饰的研究重新活跃起来 逆转m6A甲基化的酶和mRNA和m6A模式的转录组图谱 其他人的非编码RNA。综上所述，这些结果强烈表明m6A是一种高度动态的RNA 发挥重要调节作用的修饰。我们实验室最近的研究表明 M6A修饰通过与特定的细胞蛋白相互作用来发挥其功能 M6A阅读器。这项建议研究了m6A阅读器蛋白的生物学功能，并解决了 潜在的分子和细胞机制。我们已经确定了几种m6A选择性结合 蛋白质，我们的初步数据表明，这些蛋白质显著影响RNA的定位和 影响信使核糖核酸的稳定性和剪接。我们提议的研究将建立特定的、分子模型 两个人类M6A阅读器蛋白家族的M6A识别及其细胞功能和机制。 目的1将研究一种细胞质m6A阅读器蛋白的分子和细胞机制 直接识别m6A-甲基化的信使核糖核酸影响靶信使核糖核酸的定位和稳定性。 目的2研究一种核M6A阅读器蛋白的分子机制。我们发现了一种 M6A-涉及M6A诱导的RNA构象开关的开关机制。M6A诱导的 结构变化增强了mRNA结合蛋白与单链RNA基序的结合 否则嵌入到脆弱的二级结构中。 2)

N6-methyl-adenosine (m6A) is the most abundant internal modifications in messenger and long non- coding RNA. This modification occurs in many sites of mRNA with proposed functions including splicing, export, cytoplamic localization, stability, translation activity, and immune tolerance. Functional inquiries of the m6A modification have been revived since 2011 due to our discovery of human enzymes that reverse m6A methylation and transcriptome-wide mapping of m6A patterns in mRNA and non-coding RNA by others. Together, these results strongly indicate that m6A is a highly dynamic RNA modification that plays important regulatory roles. Recent studies from our laboratories indicate that m6A modifications exert their function through their interactions with specific cellular proteins termed m6A-readers. This proposal investigates biological functions of m6A-reader proteins and addresses the underlying molecular and cellular mechanisms. We have identified several m6A-selective binding proteins, and our preliminary data indicate that these proteins significantly impact RNA localization and affect mRNA stability and splicing. Our proposed research will establish specific, molecular models of m6A recognition and cellular function and mechanism of two families of human m6A-reader proteins. Aim 1 will investigate the molecular and cellular mechanisms of a cytoplasmic m6A-reader protein that directly recognizes the m6A-methylated mRNA to affect localization and stability of the target mRNA. Aim 2 will study the molecular mechanism of one nuclear m6A-reader protein. We have discovered an m6A-switch mechanism that involves m6A-induced RNA conformational switch. The m6A-induced structural change enhances binding of mRNA binding proteins to single-stranded RNA motifs that are otherwise embedded in weak secondary structures. 2)