Mitochondrial RNAs in trypanosomes are post-transcriptionally altered by uridine insertion and deletion. The information for these RNA editing processes, which are essential for the production of functional messengers, is provided by small guide RNAs. This article discusses how features of partially edited RNAs, gRNAs and chimeric RNAs, in which a gRNA is covalently linked to an editing site of pre-mRNA, have been used for the construction of models.
