Nuclear Pore Complex Protein Mediated Nuclear Localization of Dicer Protein in Human Cells

Human DICER1 protein cleaves double-stranded RNA into small sizes, a crucial step in production of single-stranded RNAs which are mediating factors of cytoplasmic RNA interference. Here, we clearly demonstrate that human DICER1 protein localizes not only to the cytoplasm but also to the nucleoplasm. We also find that human DICER1 protein associates with the NUP153 protein, one component of the nuclear pore complex. This association is detected predominantly in the cytoplasm but is also clearly distinguishable at the nuclear periphery. Additional characterization of the NUP153-DICER1 association suggests NUP153 plays a crucial role in the nuclear localization of the DICER1 protein.人类DICER1蛋白（DICER1 protein）可将双链RNA（double-stranded RNA）切割为短小RNA片段，这是作为细胞质RNA干扰（cytoplasmic RNA interference）介导因子的单链RNA生成过程中的关键步骤。本研究明确证实，人类DICER1蛋白不仅定位于细胞质，还可定位于核质（nucleoplasm）。本研究同时发现，人类DICER1蛋白可与核孔复合物（nuclear pore complex）的组分之一NUP153蛋白（NUP153 protein）相结合。该结合作用主要在细胞质中被检测到，但在核周区域（nuclear periphery）也可清晰辨别。对NUP153与DICER1结合作用的进一步表征分析显示，NUP153在DICER1蛋白的核定位（nuclear localization）过程中发挥关键作用。