Björk Petra, Wieslander Lars
Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, 106 91, Stockholm, Sweden.
Cell Mol Life Sci. 2017 Aug;74(16):2875-2897. doi: 10.1007/s00018-017-2503-3. Epub 2017 Mar 17.
Expression of protein-coding genes in eukaryotes relies on the coordinated action of many sophisticated molecular machineries. Transcription produces precursor mRNAs (pre-mRNAs) and the active gene provides an environment in which the pre-mRNAs are processed, folded, and assembled into RNA-protein (RNP) complexes. The dynamic pre-mRNPs incorporate the growing transcript, proteins, and the processing machineries, as well as the specific protein marks left after processing that are essential for export and the cytoplasmic fate of the mRNPs. After release from the gene, the mRNPs move by diffusion within the interchromatin compartment, making up pools of mRNPs. Here, splicing and polyadenylation can be completed and the mRNPs recruit the major export receptor NXF1. Export competent mRNPs interact with the nuclear pore complex, leading to export, concomitant with compositional and conformational changes of the mRNPs. We summarize the integrated nuclear processes involved in the formation and export of mRNPs.
真核生物中蛋白质编码基因的表达依赖于许多复杂分子机制的协同作用。转录产生前体mRNA（pre-mRNA），而活跃基因提供了一个环境，在此环境中前体mRNA被加工、折叠并组装成RNA-蛋白质（RNP）复合物。动态的前体mRNP包含不断增长的转录本、蛋白质、加工机制，以及加工后留下的特定蛋白质标记，这些标记对于mRNP的输出和细胞质命运至关重要。从基因释放后，mRNP在染色质间区室中通过扩散移动，形成mRNP库。在这里，剪接和聚腺苷酸化可以完成，并且mRNP招募主要的输出受体NXF1。具备输出能力的mRNP与核孔复合体相互作用，导致输出，同时伴随着mRNP的组成和构象变化。我们总结了参与mRNP形成和输出的整合核过程。
