Institute of Cell Biology, University of Bern, Bern, Switzerland.
Wiley Interdiscip Rev RNA. 2011 Jan-Feb;2(1):79-91. doi: 10.1002/wrna.35.
The formation of defined 3(') ends is an important step in the biogenesis of mRNAs. In eukaryotic cells, all mRNA 3(') ends are generated by endonucleolytic cleavage of primary transcripts in reactions that are essentially posttranscriptional. Nevertheless, 3(') end formation is tightly connected to transcription in vivo, and a link with mRNA export to the cytoplasm has been postulated. Here, we briefly review the current knowledge about the two types of mRNA 3(') end processing reactions, cleavage/polyadenylation and histone RNA processing. We then focus on factors shared between these two reactions. In particular, we discuss evidence for new functions of the mammalian cleavage factor I subunit CF I(m) 68 in histone RNA 3(') processing and in the export of mature mRNAs from the nucleus to the cytoplasm.
定义的 3' 端的形成是 mRNA 生物发生的重要步骤。在真核细胞中，所有 mRNA 3' 端都是通过初级转录本的内切核酸酶切割产生的，这些反应基本上是转录后发生的。然而，3' 端的形成与体内转录紧密相连，并且已经提出了与 mRNA 输出到细胞质的联系。在这里，我们简要回顾了关于两种类型的 mRNA 3' 端加工反应，即切割/多聚腺苷酸化和组蛋白 RNA 加工的最新知识。然后，我们专注于这两种反应共有的因素。特别是，我们讨论了哺乳动物切割因子 I 亚基 CF I(m)68 在组蛋白 RNA 3' 加工以及成熟 mRNA 从核输出到细胞质中的新功能的证据。
