Figure 3.

Typical DNA, pre-MRNA, and mRNA design sequences; UTR—untranslated region; poly(A)—polyadenylate signal tail (enumver as beeded [36]). The 5′ cap at the end allows for sequence recognition, protecting the translated molecules from digestion by nucleases [37]. The 5′UTR/3′UTR determines the translation efficiency, stability, and location; it is pivotal to optimizing expression [36,38]. The open reading frame or coding sequence (CDS) lists the genes expressed. These genes are optimized and modified to improve translational efficiencies, such as the modification of guanine and cytosine content [39]. The Poly(A) tail is essential for optimal translation 11 and improves stability by blocking digestion by 3′ exonuclease, increasing translation efficiency and adding to the molecule’s stability [40].