This non-cytotoxic synthetic modified mRNA can be used for protein expression, regulation of cell reprogramming or differentiation, and drug delivery.
Additionally, modified mRNAs have been shown to be viable and safe as therapeutic agents for gene therapy and vaccine, providing an alternative approach to address diseases.
For the synthesis of modified mRNA, mRNA synthesis was performed as reported previously.
Despite the localization of snoRNAs in the nucleolus, their ability to modify mRNA has been suggested by reports that another imprinted snoRNA, Snord115, affects alternative splicing and editing of serotonin receptor 5HT2C pre-mRNA [51], [52].
Synthesized modified mRNAs, including VASA mRNA, were produced and validated prior to use as shown (Supplementary Material, Fig. S1A and B); protein expression and localization was confirmed by immunocytochemistry (Fig. 1).
When formulated in the nanoparticle formulation liposome-protamine-RNA (LPR), modified mRNA showed increased nuclease tolerance and was more effectively taken up by tumor cells after systemic administration.
As many modified nucleosides are present in mammalian RNAs, such as pseudouridine, 2-thiouridine, 5-methylcytidine, 6-methyladenosine, inosine and many 2'- O-methylated nucleosides at the 5'-terminal cap, these nucleosides can be used for modified mRNA to reduce the immune reaction [3].
Tumor cells were transfected with LPR, which contains modified mRNA encoding HSV1-tk.
Fig. 1 The principle and applications of modified mRNA.
Eukaryotic mRNA is modified by the addition of the 7-methylguanosine 'cap' to the first transcribed nucleotide.
