Probing the closed-loop model of mRNA translation in living cells.
Probing the closed-loop model of mRNA translation in living cells.
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DOI：
10.1080/15476286.2015.1017242
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发表时间：
2015
期刊：
影响因子：
4.1
通讯作者：
Preiss T
中科院分区：
文献类型：
--
作者：
Archer SK;Shirokikh NE;Hallwirth CV;Beilharz TH;Preiss T
通过帽结构、poly（A）尾、eIF 4 E、eIF 4G和PAB之间的相互作用形成的mRNA闭环在真核翻译起始模型中具有中心特征，尽管其在体内存在的直接支持还没有很好地建立。在这里，我们使用从快速交联的细胞中分离mRNP和高通量qPCR的组合来研究闭环。使用这些因子和mRNA的相对末端之间的相互作用作为闭环的代理，我们提供的证据表明，它是普遍的eIF 4 E/4G结合，但出乎意料的稀疏PAB 1结合的mRNA，这表明它主要发生在一个不同的阶段的多核糖体组装。我们观察到mRNA特异性变化的闭环形成的程度，与多核糖体拓扑结构在基因表达的控制中的作用一致。
The mRNA closed-loop, formed through interactions between the cap structure, poly(A) tail, eIF4E, eIF4G and PAB, features centrally in models of eukaryotic translation initiation, although direct support for its existence in vivo is not well established. Here, we investigated the closed-loop using a combination of mRNP isolation from rapidly cross-linked cells and high-throughput qPCR. Using the interaction between these factors and the opposing ends of mRNAs as a proxy for the closed-loop, we provide evidence that it is prevalent for eIF4E/4G-bound but unexpectedly sparse for PAB1-bound mRNAs, suggesting it primarily occurs during a distinct phase of polysome assembly. We observed mRNA-specific variation in the extent of closed-loop formation, consistent with a role for polysome topology in the control of gene expression.