College of Life Sciences, Beijing Normal University, Beijing 100875, China.
Cell Res. 2013 May;23(5):645-57. doi: 10.1038/cr.2013.23. Epub 2013 Feb 12.
microRNAs (miRNAs) play important roles in the regulation of gene expression. In Arabidopsis, mature miRNAs are processed from primary miRNA transcripts (pri-miRNAs) by nuclear HYL1/SE/DCL1 complexes that form Dicing bodies (D-bodies). Here we report that an RNA-binding protein MOS2 binds to pri-miRNAs and is involved in efficient processing of pri-miRNAs. MOS2 does not interact with HYL1, SE, and DCL1 and is not localized in D-bodies. Interestingly, in the absence of MOS2, the recruitment of pri-miRNAs by HYL1 is greatly reduced and the localization of HYL1 in D-bodies is compromised. These data suggest that MOS2 promotes pri-miRNA processing through facilitating the recruitment of pri-miRNAs by the Dicing complexes.
microRNAs (miRNAs) 在基因表达调控中发挥重要作用。在拟南芥中，成熟的 miRNAs 由核 HYL1/SE/DCL1 复合物从初级 miRNA 转录物（pri-miRNAs）加工而来，该复合物形成 Dicing 体（D-bodies）。在这里，我们报告说一种 RNA 结合蛋白 MOS2 与 pri-miRNAs 结合，并参与 pri-miRNAs 的有效加工。MOS2 不与 HYL1、SE 和 DCL1 相互作用，也不在 D 体中定位。有趣的是，在没有 MOS2 的情况下，HYL1 对 pri-miRNAs 的募集大大减少，HYL1 在 D 体中的定位受损。这些数据表明，MOS2 通过促进 Dicing 复合物对 pri-miRNAs 的募集来促进 pri-miRNA 的加工。
