CNRS, UMR8261, Institut de Biologie Physico-Chimique, Université de Paris, 75005 Paris, France.
Nucleic Acids Res. 2021 May 7;49(8):4643-4654. doi: 10.1093/nar/gkab216.
RNase Y and RNase E are disparate endoribonucleases that govern global mRNA turnover/processing in the two evolutionary distant bacteria Bacillus subtilis and Escherichia coli, respectively. The two enzymes share a similar in vitro cleavage specificity and subcellular localization. To evaluate the potential equivalence in biological function between the two enzymes in vivo we analyzed whether and to what extent RNase E is able to replace RNase Y in B. subtilis. Full-length RNase E almost completely restores wild type growth of the rny mutant. This is matched by a surprising reversal of transcript profiles both of individual genes and on a genome-wide scale. The single most important parameter to efficient complementation is the requirement for RNase E to localize to the inner membrane while truncation of the C-terminal sequences corresponding to the degradosome scaffold has only a minor effect. We also compared the in vitro cleavage activity for the major decay initiating ribonucleases Y, E and J and show that no conclusions can be drawn with respect to their activity in vivo. Our data confirm the notion that RNase Y and RNase E have evolved through convergent evolution towards a low specificity endonuclease activity universally important in bacteria.
RNase Y 和 RNase E 是两种不同的内切核酸酶，分别控制着两种进化上相距甚远的细菌枯草芽孢杆菌和大肠杆菌中全局 mRNA 周转/加工。这两种酶具有相似的体外切割特异性和亚细胞定位。为了评估两种酶在体内生物学功能的潜在等效性，我们分析了 RNase E 是否以及在何种程度上能够替代枯草芽孢杆菌中的 RNase Y。全长 RNase E 几乎完全恢复了 rny 突变体的野生型生长。这与单个基因和全基因组水平的转录谱的惊人逆转相匹配。有效互补的最重要参数是需要 RNase E 定位于内膜，而对应于降解体支架的 C 端序列的截断只有很小的影响。我们还比较了主要降解起始核糖核酸酶 Y、E 和 J 的体外切割活性，表明不能根据它们在体内的活性得出任何结论。我们的数据证实了这样一种观点，即 RNase Y 和 RNase E 通过趋同进化演变为一种低特异性内切核酸酶活性，这种活性在细菌中普遍重要。
