HSPC117 Is the Essential Subunit of a Human tRNA Splicing Ligase Complex

  title={HSPC117 Is the Essential Subunit of a Human tRNA Splicing Ligase Complex},
  author={Johannes Popow and Markus Englert and Stefan Weitzer and Alexander Schleiffer and Beata Mierzwa and Karl Mechtler and Simon Trowitzsch and Cindy L Will and Reinhard L{\"u}hrmann and Dieter S{\"o}ll and Javier Martinez},
  pages={760 - 764}
The human enzyme that joins transfer RNA exons together is discovered. Splicing of mammalian precursor transfer RNA (tRNA) molecules involves two enzymatic steps. First, intron removal by the tRNA splicing endonuclease generates separate 5′ and 3′ exons. In animals, the second step predominantly entails direct exon ligation by an elusive RNA ligase. Using activity-guided purification of tRNA ligase from HeLa cell extracts, we identified HSPC117, a member of the UPF0027 (RtcB) family, as the… 

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