The Escherichia coli major exoribonuclease RNase II is a component of the RNA degradosome.
The Escherichia coli major exoribonuclease RNase II is a component of the RNA degradosome.
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DOI：
10.1042/bsr20140113
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发表时间：
2014-12-23
影响因子：
4
通讯作者：
Taghbalout A
中科院分区：
文献类型：
--
作者：
Lu F;Taghbalout A
执行 RNA 降解和加工功能的多蛋白复合物存在于生命各个领域的细胞中。在大肠杆菌中，RNA 降解体是一种四蛋白复合物，是正常 RNA 降解和加工所必需的。除了降解体复合物外，细胞还含有其他核糖核酸酶，它们在 RNA 加工和/或降解中也发挥着重要作用。其他核糖核酸酶是否与降解体相关或独立发挥作用尚不清楚。在目前的工作中，细胞提取物的 IP（免疫沉淀）研究表明，主要的水解核糖核酸外切酶 RNase II 与已知的降解体成分 RNaseE（核糖核酸内切酶 E）、RhlB（RNA 解旋酶 B）、PNPase（多核苷酸磷酸化酶）和 Eno（烯醇化酶）相关。 RNase II-降解体关联的进一步证据来自远西方亲和印迹实验中 RNase II 与纯化的 RNaseE 的结合。 RNase II-降解体复合物的形成需要降解体蛋白 RhlB 和 PNPase 以及包含其他降解体蛋白结合位点的 RNaseE C 末端结构域。这表明 RNase II 是 RNA 降解体复合物的一个组成部分，这是一种以前未被认识的关联，可能在耦合和协调 RNA 降解途径的多个元件中发挥作用。
Multiprotein complexes that carry out RNA degradation and processing functions are found in cells from all domains of life. In Escherichia coli, the RNA degradosome, a four-protein complex, is required for normal RNA degradation and processing. In addition to the degradosome complex, the cell contains other ribonucleases that also play important roles in RNA processing and/or degradation. Whether the other ribonucleases are associated with the degradosome or function independently is not known. In the present work, IP (immunoprecipitation) studies from cell extracts showed that the major hydrolytic exoribonuclease RNase II is associated with the known degradosome components RNaseE (endoribonuclease E), RhlB (RNA helicase B), PNPase (polynucleotide phosphorylase) and Eno (enolase). Further evidence for the RNase II-degradosome association came from the binding of RNase II to purified RNaseE in far western affinity blot experiments. Formation of the RNase II–degradosome complex required the degradosomal proteins RhlB and PNPase as well as a C-terminal domain of RNaseE that contains binding sites for the other degradosomal proteins. This shows that the RNase II is a component of the RNA degradosome complex, a previously unrecognized association that is likely to play a role in coupling and coordinating the multiple elements of the RNA degradation pathways.