Lexis and Grammar of Mitochondrial RNA Processing in Trypanosomes

Trends Parasitol. 2020 Apr;36(4):337-355. doi: 10.1016/j.pt.2020.01.006. Epub 2020 Feb 28.


Trypanosoma brucei spp. cause African human and animal trypanosomiasis, a burden on health and economy in Africa. These hemoflagellates are distinguished by a kinetoplast nucleoid containing mitochondrial DNAs of two kinds: maxicircles encoding ribosomal RNAs (rRNAs) and proteins and minicircles bearing guide RNAs (gRNAs) for mRNA editing. All RNAs are produced by a phage-type RNA polymerase as 3' extended precursors, which undergo exonucleolytic trimming. Most pre-mRNAs proceed through 3' adenylation, uridine insertion/deletion editing, and 3' A/U-tailing. The rRNAs and gRNAs are 3' uridylated. Historically, RNA editing has attracted major research effort, and recently essential pre- and postediting processing events have been discovered. Here, we classify the key players that transform primary transcripts into mature molecules and regulate their function and turnover.

Keywords: RNA decay; RNA editing; Trypanosoma; kinetoplast; mitochondria; polyadenylation.

Publication types

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

MeSH terms

  • Animals
  • RNA Editing / physiology*
  • RNA, Mitochondrial / genetics
  • RNA, Mitochondrial / metabolism*
  • RNA, Protozoan / genetics
  • RNA, Protozoan / metabolism*
  • Trypanosoma brucei brucei / genetics
  • Trypanosoma brucei brucei / metabolism*


  • RNA, Mitochondrial
  • RNA, Protozoan