Bacteriophage MS2 genomic RNA encodes an assembly instruction manual for its capsid.
Bacteriophage MS2 genomic RNA encodes an assembly instruction manual for its capsid.
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DOI：
10.1080/21597081.2016.1157666
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发表时间：
2016-01
期刊：
影响因子：
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通讯作者：
Twarock R
中科院分区：
文献类型：
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作者：
Stockley PG;White SJ;Dykeman E;Manfield I;Rolfsson O;Patel N;Bingham R;Barker A;Wroblewski E;Chandler-Bostock R;Weiß EU;Ranson NA;Tuma R;Twarock R
使用RNA-外壳蛋白交联，我们已经表明感染性MS 2病毒体内部的主要RNA识别表面与结合噬菌体基因组内的高亲和力翻译操纵子TR的已知肽重叠。数据还揭示了与外壳蛋白壳接触的基因组片段的序列。这些显示出与先前基于病毒体组装是由称为包装信号（PS）的RNA位点处的多个序列特异性接触介导的假设的预测的显著重叠。这些PS是TR茎环序列和二级结构的变异。它们协同作用以调节显性组装途径并确保同源RNA的降解。在MS 2中，它们还触发二聚体衣壳中的构象变化，产生A/B准构象异构体，需要其中的60个来完成T=3衣壳。这是迄今为止最令人信服的证明，这种ssRNA病毒，并通过暗示可能有很多，通过PS介导的组装机制组装。
Using RNA-coat protein crosslinking we have shown that the principal RNA recognition surface on the interior of infectious MS2 virions overlaps with the known peptides that bind the high affinity translational operator, TR, within the phage genome. The data also reveal the sequences of genomic fragments in contact with the coat protein shell. These show remarkable overlap with previous predictions based on the hypothesis that virion assembly is mediated by multiple sequences-specific contacts at RNA sites termed Packaging Signals (PSs). These PSs are variations on the TR stem-loop sequence and secondary structure. They act co-operatively to regulate the dominant assembly pathway and ensure cognate RNA encapsidation. In MS2, they also trigger conformational change in the dimeric capsomere creating the A/B quasi-conformer, 60 of which are needed to complete the T=3 capsid. This is the most compelling demonstration to date that this ssRNA virus, and by implications potentially very many of them, assemble via a PS-mediated assembly mechanism.