Fig. 1: Concept of how nucleoside relics of the RNA world enable RNA-based peptide synthesis.
From: A prebiotically plausible scenario of an RNA–peptide world
a, tRNA structure showing selected ribose and nucleobase modifications. The 3′-amino acid-acylated adenosine is located at the CCA 3′ end in contemporary tRNAs. 5-Methylaminomethyl uridine, mnm5U, is found in the wobble position 34. The amino acid-modified carbamoyl adenosine, (m6)aa6A (aa, amino acid), is present at position 37 in certain tRNAs. b, General RNA–peptide synthesis cycle based on mnm5U and m6aa6A. The structures of oligonucleotides are simplified and only terminal nucleobases are drawn.
