A 5'-TERMINAL STEM LOOP STRUCTURE CAN STABILIZE MESSENGER-RNA IN ESCHERICHIA-COLI
A 5'-TERMINAL STEM LOOP STRUCTURE CAN STABILIZE MESSENGER-RNA IN ESCHERICHIA-COLI
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DOI：
10.1101/gad.6.1.135
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发表时间：
1992-01-01
影响因子：
10.5
通讯作者：
BELASCO, JG
中科院分区：
文献类型：
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作者：
EMORY, SA;BOUVET, P;BELASCO, JG
长寿大肠杆菌ompA转录物的5 '非翻译区作为mRNA稳定剂发挥功能，能够延长大肠杆菌中的寿命。大肠杆菌的许多异源信息，它是融合。为了阐明细菌中差异mRNA稳定性的结构基础，已经通过突变分析鉴定了ompA 5 '-非翻译区的结构域，该结构域允许其保护mRNA免于降解。距离该RNA片段的最末端5'端不超过2-4个核苷酸的茎-环的存在对其稳定影响至关重要，而茎-环的序列相对不重要。在非常接近5'端形成发夹的可能性是许多稳定的原核信息的共同特征。此外，正常不稳定信息（bla mRNA）的寿命在大肠杆菌中可以延长。在其5'端加入一个简单的发夹结构。在不存在5 '末端茎环的情况下，ompA mRNA的加速降解似乎开始于5'末端的下游。我们建议E.以显著长度的单链RNA片段开始的大肠杆菌信使优先被降解性核糖核酸酶靶向，所述降解性核糖核酸酶在一个或多个远端位点处内部切割之前与mRNA 5'末端相互作用。
The 5'-untranslated region of the long-lived Escherichia coli ompA transcript functions as an mRNA stabilizer capable of prolonging the lifetime in E. coli of a number of heterologous messages to which it is fused. To elucidate the structural basis of differential mRNA stability in bacteria, the domains of the ompA 5'-untranslated region that allow it to protect mRNA from degradation have been identified by mutational analysis. The presence of a stem-loop no more than 2-4 nucleotides from the extreme 5' terminus of this RNA segment is crucial to its stabilizing influence, whereas the sequence of the stem-loop is relatively unimportant. The potential to form a hairpin very close to the 5' end is a feature common to a number of stable prokaryotic messages. Moreover, the lifetime of a normally labile message (bla mRNA) can be prolonged in E. coli by adding a simple hairpin structure at its 5' terminus. Accelerated degradation of ompA mRNA in the absence of a 5'-terminal stem-loop appears to start downstream of the 5' end. We propose that E. coli messages beginning with a single-stranded RNA segment of significant length are preferentially targeted by a degradative ribonuclease that interacts with the mRNA 5' terminus before cleaving internally at one or more distal sites.