n nnnMicroRNAs (miRNAs) are small silencing RNAs with regulatoryroles in gene expression. miRNAs interact with Argonaute (AGO)proteins to form effector complexes that cleave target mRNAsor repress translation. Rice (Oryza sativa) encodes four AGO1homologs (AGO1a, AGO1b, AGO1c, and AGO1d). We used RNA interference(RNAi) to knock down the four AGO1s. The RNAi lines displayedpleiotropic developmental phenotypes and had increased accumulationof miRNA targets. AGO1a, AGO1b, and AGO1c complexes were purifiedand further characterized. The three AGO1s all have a strongpreference for binding small RNAs (sRNAs) with 5' U and haveSlicer activity. We cataloged the sRNAs in each AGO1 complexby deep sequencing and found that all three AGO1s predominantlybound known miRNAs. Most of the miRNAs were evenly distributedin the three AGO1 complexes, suggesting a redundant role forthe AGO1s. Intriguingly, a subset of miRNAs were specificallyincorporated into or excluded from one of the AGO1s, suggestingfunctional specialization among the AGO1s. Furthermore, we identifiedrice miRNA targets at a global level. The validated targetsinclude transcription factors that control major stages of developmentand also genes involved in a variety of physiological processes,indicating a broad regulatory role for miRNAs in rice.展开▼
机译：ABSTRACTn n
n TOP n <字体颜色= 464c53>抽象 n 介绍 n 结果 n 讨论 n 方法 n 参考文献 n n nnnMicroRNA（miRNA）是小的沉默RNA，具有调控性 角色 基因表达。 miRNA与Argonaute（AGO） 蛋白质相互作用，形成切割靶mRNAs 或抑制翻译的效应子复合物。水稻（ Oryza sativa ）编码四个AGO1 同源物（AGO1a，AGO1b，AGO1c和AGO1d）。我们使用RNA干扰 （RNAi）敲低了四个AGO1。 RNAi系表现出 多效性发育表型，并增加了miRNA靶标的积累 。 AGO1a，AGO1b和AGO1c复合物经过纯化 并进行了进一步表征。三个AGO1都具有很强的 偏好，可以与5'U的小RNA（sRNA）结合，并且具有 Slicer活性。我们通过深度测序对每个AGO1复合物 中的sRNA进行了分类，发现所有三个AGO1主要结合了 已知的miRNA。大多数miRNA在三个AGO1复合物中均匀分布 ，表明 AGO1具有冗余作用。有趣的是，miRNA的一个子集专门 掺入或排除在其中之一之外，表明AGO1之间的 功能专门化。此外，我们在全球范围内确定了 大米miRNA目标。验证过的靶标 包括控制发育 主要阶段的转录因子，还涉及涉及多种生理过程的基因， 表明对SUP> 具有广泛的调节作用。水稻中的miRNA。展开▼
