tRNA Stabilization by Modified Nucleotides

摘要

Post-transcriptional ribonucleotide modification is a phenomenon best studied in tRNA, where itnoccursmost frequently and in great chemical diversity. This paper reviews the intrinsic network ofmodifications innthe structural core of the tRNA, which governs structural flexibility and rigidity to fine-tune the molecule to peaknperformance and to regulate its steady-state level. Structural effects ofRNAmodifications range fromnanometer-nscale rearrangements to subtle restrictions of conformational space on the angstromscale. Structural stabilizationnresulting from nucleotide modification results in increased thermal stability and translates into protection againstnunspecific degradation by bases and nucleases. Several mechanisms of specific degradation of hypomodifiedntRNA, which were only recently discovered, provide a link between structural and metabolic stability.