Winkler Wade C, Nahvi Ali, Sudarsan Narasimhan, Barrick Jeffrey E, Breaker Ronald R
Department of Molecular, Cellular and Developmental Biology, Yale University, PO Box 208103, New Haven, Connecticut 06520-8103, USA.
Nat Struct Biol. 2003 Sep;10(9):701-7. doi: 10.1038/nsb967. Epub 2003 Aug 10.
Riboswitches are metabolite-binding RNA structures that serve as genetic control elements for certain messenger RNAs. These RNA switches have been identified in all three kingdoms of life and are typically responsible for the control of genes whose protein products are involved in the biosynthesis, transport or utilization of the target metabolite. Herein, we report that a highly conserved RNA domain found in bacteria serves as a riboswitch that responds to the coenzyme S-adenosylmethionine (SAM) with remarkably high affinity and specificity. SAM riboswitches undergo structural reorganization upon introduction of SAM, and these allosteric changes regulate the expression of 26 genes in Bacillus subtilis. This and related findings indicate that direct interaction between small metabolites and allosteric mRNAs is an important and widespread form of genetic regulation in bacteria.
核糖开关是一种代谢物结合RNA结构，可作为某些信使RNA的遗传控制元件。这些RNA开关已在所有三个生命王国中被鉴定出来，通常负责控制其蛋白质产物参与目标代谢物生物合成、运输或利用的基因。在此，我们报告在细菌中发现的一个高度保守的RNA结构域作为一种核糖开关，对辅酶S-腺苷甲硫氨酸（SAM）具有极高的亲和力和特异性。引入SAM后，SAM核糖开关会发生结构重组，这些变构变化调节枯草芽孢杆菌中26个基因的表达。这一发现及相关研究结果表明，小代谢物与变构mRNA之间的直接相互作用是细菌中一种重要且广泛存在的遗传调控形式。
