Over 150 unique RNA modifications are now known including several nonstandard nucleotides present in the body of messenger RNAs. These modifications can alter a transcript's function and are collectively referred to as the epitrancriptome. Chemically modified nucleoside analogs are poised to play an important role in the study of these epitranscriptomic marks. Introduced chemical features on nucleic acid strands provide unique structures or reactivity that can be used for downstream detection or quantification. Three methods are used in the field to synthesize RNA containing chemically modified nucleoside analogs. Nucleoside analogs can be introduced by metabolic labeling, via polymerases with modified nucleotide triphosphates or via phosphoramidite-based chemical synthesis. In this review, these methods for incorporation of nucleoside analogs will be discussed with specific recently published examples pertaining to the study of the epitranscriptome.

中文翻译：

---

表观转录组研究中的核苷类似物

现在已知超过 150 种独特的 RNA 修饰，包括存在于信使 RNA 体内的几种非标准核苷酸。这些修饰可以改变转录本的功能，统称为表观转录组。化学修饰的核苷类似物有望在这些表观转录组学标记的研究中发挥重要作用。核酸链上引入的化学特征提供了独特的结构或反应性，可用于下游检测或定量。本领域使用三种方法来合成含有化学修饰核苷类似物的 RNA。核苷类似物可以通过代谢标记引入，通过聚合酶与修饰的三磷酸核苷酸或通过基于亚磷酰胺的化学合成。在这次审查中，