Antizyme RNA frameshifting stimulation element
Antizyme RNA frameshifting stimulation element is a structural element which is found in antizyme mRNA and is known to promote frameshifting. Antizyme genes have two partially overlapping open reading frames, the second, which encodes the functional (antizyme) protein requires +1 translational frameshifting.
Source: Wikipedia — Antizyme RNA frameshifting stimulation element (CC BY-SA 4.0)