Multiple PPR protein interactions are involved in the RNA editing system in Arabidopsis mitochondria and plastids

Significance RNA editing is a posttranscriptional regulation process essential for organellar function. The PPR protein family plays a major role in RNA editing, but the precise function of each member and its interactions in editosome complexes remain unclear. This research demonstrates that three PPR proteins (SLO2, NUWA, and DYW2) interact in mitochondria and provides evidence for the following: ( i ) P-type PPR protein NUWA assists in the interaction between SLO2 and DYW2, and ( ii ) DYW2 participates in E + editosomes. We hypothesize that this mechanism is common in both mitochondria and chloroplasts, where the E + -type PPR proteins, such as SLO2, target the specific RNA sites, with DYW2 suggested to provide the editing catalytic domain and NUWA assisting the interaction between the former ones.