Kaga Naoko, Umitsuki Genryou, Nagai Kazuo, Wachi Masaaki
Department of Bioengineering, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8501, Japan.
Biosci Biotechnol Biochem. 2002 Oct;66(10):2216-20. doi: 10.1271/bbb.66.2216.
Escherichia coli RNase G, encoded by the rng gene, is involved in the processing of 16S rRNA and degradation of the adhE mRNA encoding a fermentative alcohol dehydrogenase. In a search for the intracellular target RNAs of RNase G other than the 16S rRNA precursor and adhE mRNA, total cellular proteins from rng+ and rng::cat cells were compared by two-dimensional gel electrophoresis. The amount of enolase encoded by the eno gene reproducibly increased two- to three-fold in the rng::cat mutant strain compared with the rng+ parent strain. Rifampicin chase experiments showed that the half-life of the eno mRNA was some 3 times longer in the rng::cat mutant than in the wild type. These results indicate that the eno mRNA was a substrate of RNase G in vivo, in addition to 16S rRNA precursor and adhE mRNA.
由rng基因编码的大肠杆菌核糖核酸酶G参与16S核糖体RNA(rRNA)的加工以及编码发酵型乙醇脱氢酶的adhE信使核糖核酸(mRNA)的降解。为了寻找除16S rRNA前体和adhE mRNA之外核糖核酸酶G的细胞内靶RNA,通过二维凝胶电泳比较了rng⁺和rng::cat细胞的总细胞蛋白。与rng⁺亲本菌株相比,rng::cat突变菌株中由eno基因编码的烯醇化酶的量可重复性地增加了两到三倍。利福平追踪实验表明,rng::cat突变体中eno mRNA的半衰期比野生型长约3倍。这些结果表明,除了16S rRNA前体和adhE mRNA之外,eno mRNA在体内也是核糖核酸酶G的底物。