ROLES OF OPERATOR AND NON-OPERATOR RNA SEQUENCES IN BACTERIOPHAGE R17 CAPSID ASSEMBLY
ROLES OF OPERATOR AND NON-OPERATOR RNA SEQUENCES IN BACTERIOPHAGE R17 CAPSID ASSEMBLY
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DOI：
10.1016/0022-2836(88)90053-8
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发表时间：
1988-12-20
影响因子：
5.6
通讯作者：
UHLENBECK, OC
中科院分区：
文献类型：
--
作者：
BECKETT, D;WU, HN;UHLENBECK, OC
为了了解除翻译操纵子之外的序列对噬菌体 R17 组装的作用，使用 R17 外壳蛋白和多种 RNA 研究了体外衣壳组装。对于一系列相同链长的RNA寡聚体，以较低亲和力结合外壳蛋白二聚体的序列需要更高浓度的RNA和蛋白质进行组装。在一系列不同长度的非特异性RNA分子中，组装含有较长RNA的衣壳需要较低的蛋白质和RNA浓度。对于任何长度的 RNA 分子，单个高亲和力翻译操纵子序列的存在降低了衣壳组装的浓度要求。然而，对于大 RNA 分子来说，操纵子序列提供的衣壳化优势很小。实验表明，在整个组装过程中，外壳蛋白与非特异性序列的相互作用至少与它与特异性翻译操纵子序列的相互作用一样重要。根据这些数据，讨论了在体内实现 R17 基因组 RNA 选择性包装的机制。
In order to understand the role of sequences other than the translational operator on bacteriophage R17 assembly, in vitro capsid assembly was studied with R17 coat protein and a variety of RNAs. For a series of RNA oligomers of the same chain length, sequences that bind coat protein dimer with a lower affinity require higher concentrations of RNA and protein for assembly. Among a series of non-specific RNA molecules of differing lengths, lower protein and RNA concentrations are required for assembly of capsids containing longer RNAs. For RNA molecules of any length, the presence of a single high-affinity translational operator sequence lowered the concentration requirements for capsid assembly. However, the advantage for encapsidation provides by the operator sequence is small for large RNA molecules. The experiments indicate that in the overall assembly process the interaction of coat protein with non-specific sequences is at least as importnat as its interaction with the specific translational operator sequence. In light of the data, a mechanism of achieving selective packaging of the R17 genomic RNA in vivo is discussed.