NAR’s Breakthrough Articles present high-impact studies answering long-standing questions in the field of nucleic acids research and/or opening up new areas and mechanistic hypotheses for investigation. These articles are chosen by the Editors on the recommendation of Editorial Board Members and Referees. Articles are accompanied by a brief synopsis explaining the findings of the paper and where they fit in the broader context of nucleic acids research. They represent the very best papers published at NAR.
5′-fluoro(di)phosphate-labeled oligonucleotides are versatile molecular probes for studying nucleic acid secondary structure and interactions by 19F NMR
This study describes the synthesis, characterization and application of oligonucleotides carrying 5′-fluoromonophosphate (FP) or 5′ fluorodiphosphate (FPP) moieties as 19F NMR probes of DNA structure and function. The authors synthesized several such labeled oligodeoxyribonucleotides using straightforward methods that avoid commercially unavailable phosphoramidite building blocks, and then validated their utility as molecular tools to: 1) probe duplex formation and distinguish 5′-terminal mismatches, 2) monitor G-quadruplex formation, 3) detect DNA-protein interactions and 4) monitor i-motif formation and its interactions with small molecule ligands.
Reconstitution of the human tRNA splicing endonuclease complex: insight into the regulation of pre-tRNA cleavage
This study describes the biochemical reconstitution and characterization of the human tRNA Splicing Endonuclease ('TSEN') complex. This work is a major step forward in elucidating roles of the individual components of the TSEN machinery. It demonstrates that the complex is active in the presence and absence of the CLP1 kinase and confirms the identity of critical residues in the active sites of the endonuclease subunits, showing that the mechanism of tRNA cleavage is well conserved across archaeal and eukaryotic homologues. It further reveals that CLP1 is not required for TSEN mediated tRNA intron removal in vivo. Instead CLP1 functions as a negative regulator of tRNA exon ligation and intron circularization, providing insight into the role that CLP1 plays in tRNA splicing.