Engineering circular RNA for enhanced protein production

Circular RNAs (circRNAs) are stable and prevalent RNAs in eukaryotic cells that arise from back-splicing. Synthetic circRNAs and some endogenous circRNAs can encode proteins, raising the promise of circRNA as a platform for gene expression. In this study, we developed a systematic approach for rapid assembly and testing of features that affect protein production from synthetic circRNAs. To maximize circRNA translation, we optimized five elements: vector topology, 5 ' and 3 ' untranslated regions, internal ribosome entry sites and synthetic aptamers recruiting translation initiation machinery. Together, these design principles improve circRNA protein yields by several hundred-fold, provide increased translation over messenger RNA in vitro, provide more durable translation in vivo and are generalizable across multiple transgenes. Protein expression from circular RNAs is enhanced several hundred-fold by optimizing vector design.

Automated summary

In this study, a systematic approach was developed to optimize vector design and enhance protein expression from circRNAs. The optimized circRNAs showed increased translation in vitro, durable translation in vivo, and can be applied to multiple transgenes.