Emergence of synthetic mRNA: In vitro synthesis of mRNA and its applications in regenerative medicine

Nanomedicines to Deliver mRNA: State of the Art and Future Perspectives

“…The ORF is limited by the UTRs in both 5 and 3 sides. These non-coding regions do not participate directly in the codification of proteins, but their sequences, length and secondary structures are crucial for the regulation of the translation of the mRNA and the protein expression [51]. 5 UTR is involved in the initiation of translation, which is considered the most intricate step among the whole process, whereas, 3 UTR influences the mRNA stability and the extent of protein expression [52].…”

“…In both processes specific transcription factors are required to bind to enhancer or promoter sequences of DNA and regulate gene expression. However, the intracellular delivery of the transcription factors is quite limited by the plasmatic membrane [15,51], and the use of pDNA to express them also shows the risk of the insertion and of the consequent mutagenesis. Transfection of somatic cells with IVT mRNA encoding transcription factors has been assessed as an attractive alternative to conventional reprogramming and transdifferentiation of somatic cells [51], although research in this field is quite incipient and, up to date, it is limited to in vitro preclinical works.…”

“…Cellular reprogramming is based on the generation of iPSCs from a patient's adult somatic cells. Those iPSCs will be later differentiated into autologous specific cell types [5,15,51]. Alternatively, in the transdifferentiation or direct reprogramming process, adult somatic cells are transformed into cell lineages without iPSC generation [242,243].…”

Biomedical applications of mRNA nanomedicine

“…2). They include N 6 -methyladenosine (m 6 A), N 1 -methyladenosine (m 1 A), 2-thiouridine (s2U), 5-methyluridine (m5U), 5-methoxyuridine (mo5U), N 1 -methylpseudouridine (m 1 ψ), 5-methylcytidine (m5C), 5-hydroxymethylcytidine (hm5C), 5-methoxycytidine (mo5C), and 2-methylguanosine (m2G) [9, 74]. A recent study identified m 1 ψ, mo5U, and ψ as the top three favorable nucleosides for mRNA modification, which significantly augmented protein expression [75].…”

“…7, transcription factors are expressed from mRNA in the target cell, enter the cell nucleus, and bind to the enhancer or promoter sequences of genomic DNA to regulate specific gene expressions. These advantages of mRNA make it a powerful tool to modulate cell phenotype and function, suggesting great promise for regenerative medicine [74]. The pioneering use of IVT mRNA to mediate reprogramming of somatic cells was reported in 2010.…”