1. [Decoding errors--function of the ribosomal E site].
- Author
-
Bakowska-Zywicka K, Sikora M, and Twardowski T
- Subjects
- Animals, Binding Sites genetics, Escherichia coli genetics, Humans, Models, Molecular, Mutation, Missense, Ribosomal Proteins metabolism, Genomic Instability genetics, RNA, Transfer metabolism, Ribosomes metabolism
- Abstract
In the sixties of the last (20th) century James Watson presented a two-sites model for the ribosome comprising the P site for the peptidyl transfer RNA (tRNA) before peptide-bond formation and the A site, where decoding takes place according to the codon exposed there. Twenty years later the E site, which was specific for deacylated tRNA was detected. However, despite having three tRNA binding sites, only two tRNAs occupy the ribosome simultanously during protein synthesis: at the A and P sites before translocation (PRE state) and at the P and E sites after translocation (POST state). The importance of having two tRNAs in the POST state has been revealed during the last 25 years. It has been shown, that the E-tRNA prevents misincorporation of aminoacids and loss of reading frame. In other words, the ribosomal E site is a guard for accuracy of the polypeptide synthesized in the ribosomes.
- Published
- 2008