N4-acetylcytidine (ac4C) is often considered to be a conservative, chemically modified nucleoside present on tRNA and rRNA. Recent studies have shown extensive ac4C modifications in human and yeast mRNAs. ac4C helps to correctly read codons during translation and improves translation efficiency and the stability of mRNA. At present, the research of ac4C involves a variety of detection methods. The formation of ac4C is closely related to N-acetyltransferase 10 (NAT10) and its helpers, such as putative tRNA acetyltransferase (TAN1) for tRNA ac4C and small nucleolar RNA (snoRNA) for rRNA ac4C. Also, ac4C is associated with the development, progression, and prognosis of a variety of human diseases. Here, we summarize the history of ac4C research and the detection technologies of ac4C. We then summarized the role and mechanism of ac4C in gene-expression regulation and demonstrated the relevance of ac4C to a variety of human diseases, especially cancer. Finally, we list the future challenges of the ac4C research and demonstrate a research strategy for the interactions among several abundant modified nucleosides on mRNA.

N4-乙酰胞苷（ac4C）通常被认为是存在于tRNA和rRNA上的保守的，化学修饰的核苷。最近的研究表明，人和酵母mRNA中广泛的ac4C修饰。ac4C有助于在翻译过程中正确读取密码子，并提高翻译效率和mRNA的稳定性。目前，ac4C的研究涉及多种检测方法。ac4C的形成与N密切相关-乙酰基转移酶10（NAT10）及其辅助物，例如用于tRNA ac4C的推定tRNA乙酰基转移酶（TAN1）和用于rRNA ac4C的小核仁RNA（snoRNA）。而且，ac4C与多种人类疾病的发生，发展和预后相关。在这里，我们总结了ac4C的研究历史和ac4C的检测技术。然后，我们总结了ac4C在基因表达调控中的作用和机制，并证明了ac4C与多种人类疾病，尤其是癌症的相关性。最后，我们列出了ac4C研究的未来挑战，并展示了一种针对mRNA上多个丰富的修饰核苷之间相互作用的研究策略。