HSPC117 is the essential subunit of a human tRNA splicing ligase complex

Science. 2011 Feb 11;331(6018):760-4. doi: 10.1126/science.1197847.


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 essential subunit of a tRNA ligase complex. RNA interference-mediated depletion of HSPC117 inhibited maturation of intron-containing pre-tRNA both in vitro and in living cells. The high sequence conservation of HSPC117/RtcB proteins is suggestive of RNA ligase roles of this protein family in various organisms.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Exons
  • HeLa Cells
  • Humans
  • Introns
  • Molecular Sequence Data
  • Proteins / chemistry*
  • Proteins / isolation & purification
  • Proteins / metabolism*
  • RNA Interference
  • RNA Ligase (ATP) / chemistry*
  • RNA Ligase (ATP) / isolation & purification
  • RNA Ligase (ATP) / metabolism*
  • RNA Precursors / metabolism*
  • RNA Splicing*
  • RNA, Transfer / metabolism*
  • Spliceosomes / metabolism


  • Proteins
  • RNA Precursors
  • RTCB protein, human
  • RNA, Transfer
  • tRNA splicing ligase
  • RNA Ligase (ATP)