The field of mRNA vaccines has rapidly developed during the pandemic. In order to reduce the immunogenicity of mRNA vaccines, the introduction of naturally modified nucleotides was used. PseudoUridine is the most abundant modified nucleoside in RNA, also known as the “fifth nucleoside.” The introduction of pseudoUridine or N1-methylpseudoUridine into mRNA can effectively reduce the
immunogenicity caused by mRNA vaccines and enhance the stability of mRNA to promote protein expression further. As a result, the use of pseudoUridine or N1-methylpseudoUridine substitution will be the trend in mRNA vaccine production.
In 1960, scientists confirmed the existence of mRNA molecules. mRNA is a messenger molecule that
delivers genetic information carried by DNA in the nucleus to the ribosome in the cytoplasm, which
directs protein synthesis. In this way, genetic information is translated into biological functions.
2. Modification of nucleosides
mRNA-triggered inflammations prompted researchers to testdifferent sources of RNAs. Later in studies, researchers
discovered that in tRNAs-modified nucleosides, replacing
regular nucleosides with modified nucleosides attenuated
mRNA inflammatory responses, as they were unable to
activate TLR7 and TLR8.
In conclusion, pseudoUridine, an important part of mRNA vaccines, can:
Reduce mRNA activation in innate immunity
Enhance mRNA stability
Improve mRNA translation efficiency
And more roles for pseudoUridine remain to be explored in more depth of development.