Plant PPR editing factors in the cytosol of Physcomitrium patens

In order to test, whether plant RNA editing factors can function in the plant cytosol, although their activities are natively restricted to the organelles, we expressed Physcomitrium patens editing factors PPR56, PPR78 and PPR65 with different N-terminal makeups, including full length, truncated and as fusion proteins. We used either constitutive or inducible expression systems. Under inducible expression, we could detect specific editing of the respective targets, which were co-transcribed in the 3UTR of the protein coding sequence. RNA sequencing revealed that the editing factors additionally exhibited different numbers of off-targets in Physcomitriums nucleo-cytosolic transcriptome that are largely explainable by the PPR-RNA binding code.