The uridine modifications pseudouridine (Ψ), dihydrouridine, and 5-methyluridine are present in eukaryotic mRNAs. Many uridine-modifying enzymes are associated with human disease, underscoring the importance of uncovering the functions of uridine modifications in mRNAs. These modified uridines have chemical properties distinct from those of canonical uridines, which impact RNA structure and RNA–protein interactions. Ψ, the most abundant of these uridine modifications, is present across (pre-)mRNAs. Recent work has shown that many Ψs are present at intermediate to high stoichiometries that are likely conducive to function and at locations that are poised to influence pre-/mRNA processing. Technological innovations and mechanistic investigations are unveiling the functions of uridine modifications in pre-mRNA splicing, translation, and mRNA stability, which are discussed in this review.

真核 mRNA 中存在尿苷修饰假尿苷 (Ψ)、二氢尿苷和 5-甲基尿苷。许多尿苷修饰酶与人类疾病相关，这强调了揭示 mRNA 中尿苷修饰功能的重要性。这些修饰的尿苷具有与典型尿苷不同的化学性质，影响 RNA 结构和 RNA-蛋白质相互作用。Ψ 是这些尿苷修饰中最丰富的，存在于（前）mRNA 中。最近的工作表明，许多Ψ以中等到高化学计量存在，这可能有利于功能，并且存在于能够影响前/mRNA加工的位置。技术创新和机制研究正在揭示尿苷修饰在前 mRNA 剪接、翻译和 mRNA 稳定性中的功能，本综述对此进行了讨论。