Formation of the 3′ end of a eukaryotic mRNA is a key step in the production of a mature transcript. This process is mediated by a number of protein factors that cleave the pre-mRNA, add a poly(A) tail, and regulate transcription by protein dephosphorylation. Cleavage and polyadenylation specificity factor (CPSF) in humans, or cleavage and polyadenylation factor (CPF) in yeast, coordinates these enzymatic activities with each other, with RNA recognition, and with transcription. The site of pre-mRNA cleavage can strongly influence the translation, stability, and localization of the mRNA. Hence, cleavage site selection is highly regulated. The length of the poly(A) tail is also controlled to ensure that every transcript has a similar tail when it is exported from the nucleus. In this review, we summarize new mechanistic insights into mRNA 3′-end processing obtained through structural studies and biochemical reconstitution and outline outstanding questions in the field.

中文翻译：

---

真核生物 mRNA 的 3′ 端加工：机制、调节以及对基因表达的影响

真核生物 mRNA 3' 端的形成是产生成熟转录物的关键步骤。该过程由许多蛋白质因子介导，这些蛋白质因子裂解前体 mRNA、添加聚腺苷酸尾并通过蛋白质去磷酸化调节转录。人类中的裂解和聚腺苷酸化特异性因子 (CPSF) 或酵母中的裂解和聚腺苷酸化因子 (CPF) 通过 RNA 识别和转录相互协调这些酶活性。 mRNA 前体切割位点可以强烈影响 mRNA 的翻译、稳定性和定位。因此，切割位点的选择受到高度调控。 Poly(A) 尾部的长度也受到控制，以确保每个转录本从细胞核输出时具有相似的尾部。在这篇综述中，我们总结了通过结构研究和生化重建获得的 mRNA 3' 末端加工的新机制见解，并概述了该领域的突出问题。