核开关：一个新的基因调控元件，一类潜在的药物靶点

核开关是一类通过结合小分子代谢物调控基因表达的mRNA元件.它位于特定的mRNA区域，可以不依赖任何蛋白质因子而直接结合小分子代谢物，继而发生构象重排，影响该mRNA的活动.核开关在特定细菌中，参与调控包括维生素B₁₂和甲硫氨酸生物合成等在内的代谢途径.核开关的发现，尤其是其可以特异性紧密结合特定配体，从而精确调控生物基本代谢途径的特征，使人们开始关注它在科研和医学上的应用潜力.核开关的研究进展、主要特点和作用机制已经引起了人们的关注和思考.

Riboswitches: a Novel Gene Regulatory Element and a Potential Class of Drug Targets

Riboswitches are metabolite-binding RNA structures that serve as a novel gene regulatory element for mRNAs. Located in certain mRNAs, they can directly bind relevant small metabolites but not protein factors, and subsequently allosteric rearrangements modulate associated mRNA activities. They are believed to regulate in a wide set of fundamental metabolic pathways including vitamin B₁₂ and methionine biosynthesis in bacteria. The recent discovery of natural riboswitches, especially its property that precisely controlling basic metabolic pathways via binding to certain ligands with high affinity and specificity, inspires scientists to notice its potential application in medical research. The progress on the riboswitches, its characteristics, the function mechanism as well as the thinking and research trend triggered by its finding were introduced.