Fujioka Yoichiro, Utsumi Maki, Ohba Yusuke, Watanabe Yuichiro
Department of Life Sciences, Graduate School of Arts and Sciences, University of Tokyo, Komaba 3-8-1, Meguro, Tokyo, Japan.
Plant Cell Physiol. 2007 Sep;48(9):1243-53. doi: 10.1093/pcp/pcm099. Epub 2007 Aug 3.
There has been much recent research on the contribution of microRNA (miRNA) in plant organogenesis and hormone action. In plants, it has been reported that Dicer-like 1 (DCL1), HYPONASTIC LEAVES1 (HYL1) and SERRATE (SE) are involved in the production of miRNAs. The means by which miRNAs are processed and transported is not well understood in detail, however. In this study, we investigated the intracellular localization and intermolecular interaction of these molecules using imaging techniques, including bimolecular fluorescence complementation and fluorescence resonance energy transfer techniques, making use of various enhanced fluorescent proteins. We found that DCL1, HYL1 and SE formed bodies which localized in the nuclei. We were also able to locate the miRNA primary transcript using an MS2-tagged method on these bodies. It appears very likely that the observed DCL1-HYL1-SE nuclear body is involved in miRNA production. Co-expression of SmD3 or SmB proteins revealed the localization of DCL1-HYL1-SE complexes in the SmD3/SmB nuclear bodies.
最近有许多关于微小RNA（miRNA）在植物器官发生和激素作用中贡献的研究。在植物中，据报道，类Dicer 1（DCL1）、下弯叶1（HYL1）和锯齿状（SE）参与miRNA的产生。然而，miRNA的加工和运输方式尚未得到详细了解。在本研究中，我们利用成像技术，包括双分子荧光互补和荧光共振能量转移技术，使用各种增强型荧光蛋白，研究了这些分子的细胞内定位和分子间相互作用。我们发现DCL1、HYL1和SE形成了定位于细胞核的小体。我们还能够使用MS2标记方法在这些小体上定位miRNA初级转录本。观察到的DCL1-HYL1-SE核小体很可能参与miRNA的产生。SmD3或SmB蛋白的共表达揭示了DCL1-HYL1-SE复合物在SmD3/SmB核小体中的定位。
