Mencia Regina, Gonzalo Lucía, Tossolini Ileana, Manavella Pablo A
Instituto de Agrobiotecnología del Litoral (CONICET-UNL), Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, 3000 Santa Fe, Argentina.
J Exp Bot. 2023 Apr 9;74(7):2213-2227. doi: 10.1093/jxb/erac322.
For many years we have studied the processes involved in producing miRNAs in plants and the numerous differences from their metazoan counterpart. A well-defined catalytic process, mostly carried out by the RNase III enzyme DICER-LIKE1 (DCL1), it was identified early after the discovery of RNAi and was followed by the isolation of a plethora of miRNA biogenesis cofactors. The production of miRNAs, which later are loaded in ARGONAUTE (AGO) proteins to perform their RNA silencing functions both within the cell and non-cell autonomously, appears to be a highly regulated and dynamic process. Many regulatory events during miRNA biogenesis require the action of specific proteins. However, in recent years, many post-transcriptional modifications, structural features, and coupling with other cellular processing emerged as critical elements controlling the production of miRNA and, thus, a plant's physiology. This review discusses new evidence that has changed the way we understand how miRNAs are produced in plants. We also provide an updated view of the miRNA biogenesis pathways, focusing on the gaps in our knowledge and the most compelling questions that remain open.
多年来，我们一直在研究植物中产生微小RNA（miRNA）的过程以及它们与后生动物对应物的众多差异。这是一个定义明确的催化过程，主要由核糖核酸酶III（RNase III）类酶DICER-LIKE1（DCL1）执行。在RNA干扰（RNAi）发现后不久就被识别出来，随后分离出了大量的miRNA生物合成辅助因子。miRNA的产生过程，这些miRNA随后被装载到AGO蛋白中，在细胞内和非细胞自主地执行其RNA沉默功能，这似乎是一个高度调控且动态的过程。miRNA生物合成过程中的许多调控事件都需要特定蛋白质的作用。然而，近年来，许多转录后修饰、结构特征以及与其他细胞过程的偶联已成为控制miRNA产生进而控制植物生理学的关键因素。本综述讨论了改变我们对植物中miRNA产生方式理解的新证据。我们还提供了miRNA生物合成途径的最新观点，重点关注我们知识中的空白以及仍未解决的最引人注目的问题。
