Zemp Ivo, Kutay Ulrike
Institute of Biochemistry, HPM F11.1, Schafmattstr. 18, ETH Zurich, 8093 Zurich, Switzerland.
FEBS Lett. 2007 Jun 19;581(15):2783-93. doi: 10.1016/j.febslet.2007.05.013. Epub 2007 May 11.
Based on the characterization of ribosome precursor particles and associated trans-acting factors, a biogenesis pathway for the 40S and 60S subunits has emerged. After nuclear synthesis and assembly steps, pre-ribosomal subunits are exported through the nuclear pore complex in a Crm1- and RanGTP-dependent manner. Subsequent cytoplasmic biogenesis steps of pre-60S particles include the facilitated release of several non-ribosomal proteins, yielding fully functional 60S subunits. Cytoplasmic maturation of 40S subunit precursors includes rRNA dimethylation and pre-rRNA cleavage, allowing 40S subunits to achieve translation competence. We review current knowledge of nuclear export and cytoplasmic maturation of ribosomal subunits.
基于核糖体前体颗粒及相关反式作用因子的特性，40S和60S亚基的生物发生途径已逐渐明晰。经过细胞核内的合成和组装步骤后，核糖体前体亚基以依赖Crm1和RanGTP的方式通过核孔复合体输出。60S前体颗粒随后的胞质生物发生步骤包括几种非核糖体蛋白的顺利释放，从而产生功能完备的60S亚基。40S亚基前体的胞质成熟过程包括rRNA二甲基化和前体rRNA切割，使40S亚基具备翻译能力。我们综述了核糖体亚基核输出及胞质成熟的现有知识。
