Redel, BK., et. al. (2018) Biotechniques 64:118-124. https://www.biotechniques.com/BiotechniquesJournal/2018/March/Single-step-production-of-Cas9-mRNA-for-zygote-injection/biotechniques-366753.html
With the use of DNA-free CRISPR gene editing on the rise, more researchers are turning to in vitro transcription (IVT) of Cas9 mRNA for delivery of the gene editing protein. Traditionally this involves the addition of a 5’ cap and 3’ polyadenylation post-IVT to ensure transcript stability. This paper describes a new method that does not require these additional steps by using a new Cas9 mRNA that contains a triple helical tail originating from the mMalat1 gene instead of the traditional polyA tail. Additionally, this new mRNA has a defined and fixed length that allows researchers to better assesses mRNA degradation.