DiMari J F, Bechhofer D H
Department of Biochemistry, Mount Sinai School of Medicine, New York, New York 10029.
Mol Microbiol. 1993 Mar;7(5):705-17. doi: 10.1111/j.1365-2958.1993.tb01161.x.
Ribosome stalling in the leader region of ermC mRNA results in a 10-15-fold increase in ermC mRNA half-life in Bacillus subtilis. Fusion of the ermC 5' regulatory region to several B. subtilis coding sequences resulted in induced stability of the fusion RNAs, showing that the ermC 5' region acts as a general '5' stabilizer'. RNA products of an ermC-lacZ transcriptional fusion were inducibly stable in the complete absence of translation and included a small RNA that is likely to be a decay product arising by blockage of a 3'-to-5' exoribonuclease activity. Insertion of sequences that encode endonucleolytic cleavage sites into the ermC coding sequence resulted in cleavage products whose stability depended on the nature of their 5' and 3' ends. It can be concluded from this study that initiation of mRNA decay in B. subtilis generally occurs at or near the 5' terminus.
在枯草芽孢杆菌中，核糖体在ermC mRNA的前导区域停滞会导致ermC mRNA半衰期增加10至15倍。将ermC 5'调控区域与几个枯草芽孢杆菌编码序列融合，导致融合RNA的稳定性增加，表明ermC 5'区域作为一种通用的“5'稳定剂”发挥作用。ermC-lacZ转录融合的RNA产物在完全没有翻译的情况下可诱导稳定，并且包括一种小RNA，它可能是由于3'至5'外切核糖核酸酶活性受阻而产生的降解产物。将编码内切核酸酶切割位点的序列插入ermC编码序列中，会产生其稳定性取决于其5'和3'末端性质的切割产物。从这项研究可以得出结论，枯草芽孢杆菌中mRNA降解的起始通常发生在5'末端或其附近。
