RNA degradosomes exist in vivo in Escherichia coli as multicomponent complexes associated with the cytoplasmic membrane via the N-terminal region of ribonuclease E.
RNA degradosomes exist in vivo in Escherichia coli as multicomponent complexes associated with the cytoplasmic membrane via the N-terminal region of ribonuclease E.
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RNA 降解体作为多组分复合物存在于大肠杆菌体内，通过核糖核酸酶 E 的 N 末端区域与细胞质膜相关。
DOI：
10.1073/pnas.98.1.63
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发表时间：
2001
影响因子：
11.1
通讯作者：
Lin-Chao,S
中科院分区：
文献类型：
--
作者：
Liou,GG;Jane,WN;Cohen,SN;Lin,NS;Lin-Chao,S
从大肠杆菌中分离出的RNase E与RNA降解中涉及的其他蛋白质一起包含在多组分“降解体”复合物中。早期的工作已经表明，RNase E的C-末端区域是降解体组分结合的支架，并且已经鉴定了其与多核苷酸磷酸化酶（PNIPs）、RhlB RNA解旋酶和烯醇化酶相互作用所必需的特异性RNase E区段。在这里，我们报告的电子显微镜研究，使用免疫金标记和冷冻断裂的方法，以显示降解体restrictin vivoinE。大肠杆菌的多组分结构，通过RNase E的N-末端区域与细胞质膜结合。而E.大肠杆菌蛋白相对于RNA酶E大大过量，因此在细胞中主要作为未与RNA酶E支架连接的分子被检测到，免疫金标记和生物化学分析表明，在所有细胞生长阶段，解旋酶以与RNA酶E大致等摩尔的量存在。我们的研究结果，建立了基于RNase E的降解体在vivoinE中的存在和细胞定位。大肠杆菌的研究还表明，RNA的加工和降解可能发生在细胞内的特定部位。
RNase E isolated fromEscherichia coliis contained in a multicomponent “degradosome” complex with other proteins implicated in RNA decay. Earlier work has shown that the C-terminal region of RNase E is a scaffold for the binding of degradosome components and has identified specific RNase E segments necessary for its interaction with polynucleotide phosphorylase (PNPase), RhlB RNA helicase, and enolase. Here, we report electron microscopy studies that use immunogold labeling and freeze–fracture methods to show that degradosomes existin vivoinE. colias multicomponent structures that associate with the cytoplasmic membrane via the N-terminal region of RNase E. Whereas PNPase and enolase are present inE. coliin large excess relative to RNase E and therefore are detected in cells largely as molecules unlinked to the RNase E scaffold, immunogold labeling and biochemical analyses show that helicase is present in approximately equimolar amounts to RNase E at all cell growth stages. Our findings, which establish the existence and cellular location of RNase E-based degradosomesin vivoinE. coli, also suggest that RNA processing and decay may occur at specific sites within cells.