2013 年 77 巻 12 号 p. 2473-2479
Escherichia coli RNase G is involved in the degradation of several mRNAs, including adhE and eno, which encode alcohol dehydrogenase and enolase respectively. Previous research indicates that the 5' untranslated region (5'-UTR) of adhE mRNA gives RNase G-dependency to lacZ mRNA when tagged at the 5'-end, but it has not been elucidated yet how RNase G recognizes adhE mRNA. Primer extension analysis revealed that RNase G cleaved a phosphodiester bond between −19A and −18C in the 5'-UTR (the A of the start codon was defined as +1). Site-directed mutagenesis indicated that RNase G did not recognize the nucleotides at −19 and −18. Random deletion analysis indicated that the sequence from −145 to −125 was required for RNase G-dependent degradation. Secondary structure prediction and further site-directed deletion suggested that the stem-loop structure, with a bubble in the stem, is required for RNaseG-dependent degradation of adhE mRNA.