Inducible orthogonal aminoacylation demonstrates that charging is required for mitochondrial tRNA import in Trypanosoma brucei

Sci Rep. 2019 Jul 25;9(1):10836. doi: 10.1038/s41598-019-47268-4.


Orthogonal aminoacyl-tRNA synthetase/tRNA pairs have emerged as powerful means of site-specifically introducing non-standard amino acids into proteins in vivo. Using amino acids with crosslinking moieties this method allows the identification of transient protein-protein interactions. Here we have introduced a previously characterized evolved tyrosyl-tRNA synthetase/suppressor tRNATyr pair from E. coli into the parasitic protozoan Trypanosoma brucei. Upon addition of a suitable non-standard amino acid the suppressor tRNATyr was charged and allowed translation of a green fluorescent protein whose gene contained a nonsense mutation. - T. brucei is unusual in that its mitochondrion lacks tRNA genes indicating that all its organellar tRNAs are imported from the cytosol. Expression of the bacterial tyrosyl-tRNA synthetase in our system is tetracycline-inducible. We have therefore used it to demonstrate that cytosolic aminoacylation of the suppressor tRNATyr induces its import into the mitochondrion.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aminoacylation
  • Green Fluorescent Proteins / genetics
  • Green Fluorescent Proteins / metabolism
  • Mitochondria / metabolism*
  • RNA Interference
  • RNA, Mitochondrial / metabolism*
  • RNA, Transfer / genetics
  • RNA, Transfer / metabolism*
  • Trypanosoma brucei brucei / genetics
  • Trypanosoma brucei brucei / metabolism*


  • RNA, Mitochondrial
  • Green Fluorescent Proteins
  • RNA, Transfer