File:Riboswitch-Based Intracellular Metabolite Sensor.jpg

English: A basic schematic is shown here where the purple stars indicate the metabolite and the yellow arrow shows the reporter gene. The cells with a lower concentration of the metabolite have more riboswitches in the unbound state. The unbound conformation has an unstructured interaction between the ribosome binding site (RBS) and the blue and green segments. This unstructured interaction allows for the reporter gene to be translated efficiently downstream and produce a high signal output. At a higher metabolite concentration, the riboswitches form a bound conformation where the blue segment of the riboswitch interacts with the target RNA. This allows the green segment to interact with the RBS instead, and this allows the RBs to inhibit translation initiation of the reporter gene. Because of this, the signal output is lower than with the low concentration of the metabolite.