Pseudouridiinin

Pseudouridine is a modified nucleoside that is an isomer of uridine. In pseudouridine, the glycosidic bond is formed between the uracil base and the ribose sugar at the C5 position of uracil instead of the usual N1 position. This structural difference leads to unique chemical and biological properties compared to uridine.

Pseudouridine is the most abundant modified nucleoside found in all types of RNA, including messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA). It is incorporated into RNA molecules through a process called pseudouridylation, catalyzed by enzymes known as pseudouridine synthases. This modification is a post-transcriptional event, meaning it occurs after the RNA molecule has been synthesized.

The presence of pseudouridine in RNA has significant functional implications. In tRNA, it is often found in the anticodon loop and contributes to the stability and proper folding of the tRNA molecule. In mRNA, pseudouridine modifications can influence translation efficiency and mRNA stability. Research has also indicated that pseudouridine can play a role in cellular responses to stress and in immune system regulation. Synthetic mRNA vaccines, for instance, utilize pseudouridine to enhance stability and reduce immunogenicity.