The spliceosome deposits multiple proteins 20-24 nucleotides upstream of mRNA exon-exon junctions
The spliceosome deposits multiple proteins 20-24 nucleotides upstream of mRNA exon-exon junctions
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DOI：
10.1093/emboj/19.24.6860
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发表时间：
2000-12-15
期刊：
影响因子：
11.4
通讯作者：
Moore, MJ
中科院分区：
文献类型：
--
作者：
Le Hir, H;Izaurralde, E;Moore, MJ
真核mRNA作为核糖核蛋白颗粒（MRNP）存在于体内，mRNP的蛋白质成分在mRNA代谢中具有重要功能，包括对亚细胞定位，翻译效率和mRNA半衰期的影响。有积极的证据表明，前MRNA剪接可以改变MRNP结构，从而影响下游mRNA代谢。在这里，我们报告说，剪接体稳定地沉积了几种蛋白质的mRNA，可能是一个类似于335 kDa的单个复合物。该复合物可保护mRNA的8个核苷酸免受外显子 - 外激孔连接上游20-24个核苷酸的完整RNase消化。 Splicing-dependent RNase protection of this region was observed in both HeLa cell nuclear extracts and Xenopus laevis oocyte nuclei, Immunoprecipitations revealed that five components of the complex are the splicing-associated factors SRm160, DEK and RNPS1, the mRNA-associated shuttling protein Y14 and mRNA输出因子参考，该复合物在讨论了剪接mRNA的核质转运，以及废话介导的mRNA衰变途径。
Eukaryotic mRNAs exist in vivo as ribonucleoprotein particles (mRNPs), The protein components of mRNPs have important functions in mRNA metabolism, including effects on subcellular localization, translational efficiency and mRNA half-life. There is accumulating evidence that pre-mRNA splicing can alter mRNP structure and thereby affect downstream mRNA metabolism. Here, we report that the spliceosome stably deposits several proteins on mRNAs, probably as a single complex of similar to 335 kDa. This complex protects 8 nucleotides of mRNA from complete RNase digestion at a conserved position 20-24 nucleotides upstream of exon-exon junctions. Splicing-dependent RNase protection of this region was observed in both HeLa cell nuclear extracts and Xenopus laevis oocyte nuclei, Immunoprecipitations revealed that five components of the complex are the splicing-associated factors SRm160, DEK and RNPS1, the mRNA-associated shuttling protein Y14 and the mRNA export factor REF, Possible functions for this complex in nucleocytoplasmic transport of spliced mRNA, as well as the nonsense-mediated mRNA decay pathway, are discussed.