RNA Editing in Mitochondria and Plastids: Weird and Widespread

Though widespread, RNA editing is rare, except in endosymbiotic organelles. A combination of higher mutation rates, relaxation of energetic constraints, and high genetic drift is found within plastids and mitochondria and is conducive for evolution and expansion of editing processes, possibly starting as repair mechanisms. To illustrate this, we present an exhaustive phylogenetic overview of editing types. Though widespread, RNA editing is rare, except in endosymbiotic organelles. A combination of higher mutation rates, relaxation of energetic constraints, and high genetic drift is found within plastids and mitochondria and is conducive for evolution and expansion of editing processes, possibly starting as repair mechanisms. To illustrate this, we present an exhaustive phylogenetic overview of editing types. the post-transcriptional change of specific nucleotide bases by deaminases. the hypothesis postulating that molecular mechanisms can evolve in the absence of evolutionary benefits. the conversion of another cell into a eukaryotic organelle following uptake. Origin of mitochondria and plastids. with diplonemids and kinetoplastids, they constitute the protist group Euglenozoa. the process by which eukaryotes evolved from archaea and bacteria. changes in the population frequency of gene variants due to random (non-selected) fluctuations of the population. the uninterrupted triplet protein-coding sequence from start to stop codon. a large family of RNA-binding proteins. The PPR is a 35-amino acid motif, combinations of which allow highly specific RNA sequence recognition. the (non-splicing) co/post-transcriptional alteration of RNA sequences, such that they differ from their DNA templates.