β-Pseudouridine is the C-5 glycoside isomer of the nucleoside uridine. It is formed when uridine in RNA undergoes site-specific isomerization by a pseudouridine synthase enzyme. Pseudouridine is found in tRNAs from bacteria, archaea, and eukaryotes. In vitro, it reduces the number of X-ray-induced chromosomal aberrations in human lymphocytes isolated from whole blood in a dose-dependent manner.
An isomer of the nucleoside uridine found in all species and in many classes of RNA except mRNA. It is formed by enzymes called Ψ synthases, which post-transcriptionally isomerize specific uridine residues in RNA in a process termed pseudouridylation. Studies suggest that β-Pseudouridine reduces radiation-induced chromosome aberrations in human lymphocytes.
ChEBI: Pseudouridine is a C-glycosyl pyrimidine that consists of uracil having a beta-D-ribofuranosyl residue attached at position 5. The C-glycosyl isomer of the nucleoside uridine. It has a role as a fundamental metabolite.
Pseudouridine (Ψ) was the first modified ribonucleotide discovered 7 decades ago, and it has been found in tRNA, rRNA, snRNA, mRNA, and other types of RNA[2].
Pseudouridine is essential for rRNA folding and for regulating translational accuracy and it is required for stabilizing the tRNA structure. Pseudouridine in rRNA and tRNA has been shown to fine-tune and stabilize the regional structure and help maintain their functions in mRNA decoding, ribosome assembly, processing and translation. Pseudouridine in snRNA has been shown to enhance spliceosomal RNA-pre-mRNA interaction to facilitate splicing regulation[1].
Human Endogenous Metabolite
Structure and conformation
Pseudouridine, being one of them, is the C5-glycoside isomer of uridine that contains a C-C bond between C1 of the ribose sugar and C5 of uracil, rather than usual C1-N1 bond found in uridine. The C-C bond gives it more rotational freedom and conformational flexibility.In addition, pseudouridine has an extra hydrogen bond donor at the N1 position.
[1] Mingjia Chen, Claus-Peter Witte. “A Kinase and a Glycosylase Catabolize Pseudouridine in the Peroxisome to Prevent Toxic Pseudouridine Monophosphate Accumulation.” Plant Cell 32 3 (2020): 722–739.
[2] Pedro Morais, Yi-Tao Yu, Hironori Adachi. “The Critical Contribution of Pseudouridine to mRNA COVID-19 Vaccines.” Frontiers in Cell and Developmental Biology (2021): 789427.
