Giudicatti Axel J, Tomassi Ariel H, Manavella Pablo A, Arce Agustin L
Instituto de Agrobiotecnología del Litoral (CONICET-UNL), Cátedra de Biología Celular y Molecular, Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, 3000 Santa Fe, Argentina.
Plants (Basel). 2021 Jan 30;10(2):267. doi: 10.3390/plants10020267.
MicroRNAs are small regulatory RNAs involved in several processes in plants ranging from development and stress responses to defense against pathogens. In order to accomplish their molecular functions, miRNAs are methylated and loaded into one ARGONAUTE (AGO) protein, commonly known as AGO1, to stabilize and protect the molecule and to assemble a functional RNA-induced silencing complex (RISC). A specific machinery controls miRNA turnover to ensure the silencing release of targeted-genes in given circumstances. The trimming and tailing of miRNAs are fundamental modifications related to their turnover and, hence, to their action. In order to gain a better understanding of these modifications, we analyzed small RNA sequencing data from a diversity of mutants, related to miRNA biogenesis, action, and turnover, and from different cellular fractions and immunoprecipitations. Besides confirming the effects of known players in these pathways, we found increased trimming and tailing in miRNA biogenesis mutants. More importantly, our analysis allowed us to reveal the importance of ARGONAUTE 1 (AGO1) loading, slicing activity, and cellular localization in trimming and tailing of miRNAs.
微小RNA是一类小的调节性RNA，参与植物从发育、应激反应到病原体防御等多个过程。为了实现其分子功能，微小RNA会被甲基化并装载到一种AGO蛋白（通常称为AGO1）中，以稳定和保护分子，并组装成功能性的RNA诱导沉默复合体（RISC）。一种特定的机制控制微小RNA的周转，以确保在特定情况下靶基因的沉默释放。微小RNA的修剪和加尾是与其周转相关的基本修饰，因此也与其作用相关。为了更好地理解这些修饰，我们分析了来自各种与微小RNA生物合成、作用和周转相关的突变体，以及来自不同细胞组分和免疫沉淀的小RNA测序数据。除了证实这些途径中已知参与者的作用外，我们还发现微小RNA生物合成突变体中的修剪和加尾增加。更重要的是，我们的分析使我们能够揭示AGO1装载、切割活性和细胞定位在微小RNA修剪和加尾中的重要性。
