Translation is required to remove Y14 from mRNAs in the cytoplasm
Translation is required to remove Y14 from mRNAs in the cytoplasm
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DOI：
10.1016/s0960-9822(02)00902-8
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发表时间：
2002-07-09
期刊：
影响因子：
9.2
通讯作者：
Dreyfuss, G
中科院分区：
文献类型：
--
作者：
Dostie, J;Dreyfuss, G
背景：Y14是一种RNA结合蛋白，是一个多蛋白复合体的一部分，外显子-外显子连接复合体(EJC)组装在剪接产生的mRNAs的外显子-外显子连接上。Y14的位置特异性结合在mRNAs输出到细胞质后持续存在。因此，Y14与其相互作用的蛋白质一起，具有向细胞质传递mRNA的加工历史的能力，包括被移除的内含子的位置，这些信息可能对定义提前终止密码子很重要。Y14和EJC的其他成分是如何从mRNAs中移除到细胞质中的，目前还不清楚。结果：我们发现Y14而不是另一种EJC成分Aly/ref存在于每个mRNA含有一个核糖体的多聚体组分中。在体外剪接/翻译耦合系统中使用报告构建，我们表明Y14仍然与未翻译的mRNAs相关，但从翻译活性的mRNAs中移除。重要的是，体内翻译被阻止的mRNAs存在强大的二级5‘UTR结构，Y14保留在细胞质中。结论：这些发现表明，Y14在翻译之前一直与细胞质中的mRNAs相关，需要翻译才能从mRNAs中移除Y14。因此，翻译过程去除了剪接依赖的EJC蛋白印记，这很可能在监测mRNAs以定义提前终止密码子，也可能在调节细胞质mRNAs的翻译活性方面发挥作用。
Background: Y14 is an RNA binding protein which is part of a multiprotein complex, the exon-exon junction complex (EJC), that assembles on the exon-exon junctions of mRNAs produced by splicing. The position-specific binding of Y14 persists on mRNAs after their export to the cytoplasm. Thus, Y14, together with its interacting proteins, has the capacity to communicate to the cytoplasm the processing history of the mRNA, including the position of the removed introns, information that is likely to be important for defining premature termination codons. How Y14 and other components of the EJC are removed from mRNAs into the cytoplasm has not been determined.Results: We show that Y14 but not another EJC component, Aly/REF, is present in polysome profile fractions containing one ribosome per mRNA. Using reporter constructs in an in vitro splicing/translation-coupled system, we show that Y14 remains associated with untranslated mRNAs but is removed from translationally active mRNAs. Importantly, mRNAs whose translation in vivo is prevented by the presence of strong secondary 5' UTR structure retain Y14 in the cytoplasm.Conclusions: These findings indicate that Y14 remains associated with mRNAs in the cytoplasm until they are translated, and translation is required to remove Y14 from mRNAs. Thus, the process of translation removes the splicing-dependent EJC protein imprints, which most likely function in the surveillance of mRNAs to define premature termination codons and possibly also in modulating the translation activity of cytoplasmic mRNAs.