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作 者 ：孙慧颖1，2#，郝亚娟1，2#，平晓丽1，2，黄春敏1，杨 莹1，孙宝发1，杨运桂1*

期 刊 ：生命科学 2016年 28卷 5期 页码：539-550

摘 要 ：RNA 可以被100 余种化学修饰所修饰。这些化学修饰以甲基化为主，广泛分布于各种类型的RNA 中，如rRNA、tRNA、snRNA、snoRNA 和mRNA 等，其中针对mRNA 内部修饰丰度最高的6- 甲基腺嘌呤(m6A) 的研究最为深入。m6A 修饰酶( 甲基转移酶METTL3/METTL14/WTAP 和去甲基化酶ALKBH5 与FTO) 和结合蛋白YTHDF2、YTHDF1 与YTHDC1 的发现，证明了RNA 甲基化修饰同DNA甲基化修饰一样是动态可逆的，从而将RNA 甲基化修饰由微调控机制提升到表观转录组新层次。而候选m5C 修饰甲基转移酶NSUN 家族蛋白和去甲基化酶TET 蛋白的初步鉴定，丰富了RNA 甲基化修饰表观转录组研究内涵。RNA 甲基化介导的表观转录组学调控和作用已成为RNA 生物学新研究领域。现重点回顾和展望RNA 的m6A 和m5C 甲基化修饰特征及其潜在生物学功能。

Abstract:Over 100 types of chemical modifications have been identified in various types of RNAs including rRNA， tRNA， snRNA， snoRNA and mRNA， among which methylation is most common. The N6-methyl-adenosine (m6A) as the most common and abundant internal modification on mRNA molecules has been widely studied. The recent identification of m6A modifying enzymes including methyltransferase complex METTL3/METTL14/WTAP， two demethylases ALKBH5 and FTO and binding proteins YTHDF2， YTHDF1 and YTHDC1， indicates that RNA methylation is reversible and represents a novel epitranscriptomic mechanism instead of micro-regulation in gene expression control. Identification of candidate m5C modifying enzymes NSUN family proteins and TET proteins further expands RNA methylation-mediated epitranscriptomics. Epitranscriptomics has become a new research frontier in RNA biology. This review summarizes recent progress in RNA m6A and m5C methylations and proposes their potential biological significance.

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