This occlusion prevents the ribosome from initiating translation, effectively shutting down gene expression. Riboswitches are regulatory elements found in the untranslated regions (UTRs) of mRNA molecules. They are composed of two main domains: an aptamer domain that binds to a specific small molecule or ion, and an expression platform that controls gene expression in response to the binding event. Riboswitches have been found in a wide range of organisms and play important roles in regulating various cellular processes.
