Genetic Control by Metabolite‐Binding Riboswitches

Metabolite-sensing mRNAs: Riboswitches are highly structured RNA domains that typically reside in the 5′-untranslated regions of certain bacterial mRNAs. These RNA domains serve as ligand-dependent genetic switches that provide a means by which RNA can control gene expression without the need for protein factors. Distinct classes of riboswitches are responsive to seven different metabolites and guide the maintenance of fundamental biochemical processes. One example is the regulation of the E. coli thiM mRNA by thiamine pyrophosphate (TPP; see representation).