DYW cytidine deaminase domains have a long-range impact on RNA recognition by the PPR array of chimeric plant C-to-U RNA editing factors and strongly affect target selection.

The protein factors for the specific C-to-U RNA editing events in plant mitochondria and chloroplasts possess unique arrays of RNA-binding pentatricopeptide repeats (PPRs) linked to carboxy-terminal cytidine deaminase DYW domains via the extension motifs E1 and E2. The E1 and E2 motifs have distant similarities to tetratricopeptide repeats known to mediate protein-protein interactions but their precise function is unclear. Here, we investigate the tolerance of PPR56 and PPR65, two functionally characterized RNA editing factors of the moss Physcomitrium patens, for the creation of chimeras by variably replacing their C-terminal protein regions. Making use of a heterologous RNA editing assay system in Escherichia coli we find that heterologous DYW domains can strongly restrict or widen the spectrum of off-targets in the bacterial transcriptome for PPR56. Surprisingly, our data suggest that these changes are not only caused by the preference of a given heterologous DYW domain for the immediate sequence environment of the cytidine to be edited but also by a long-range impact on the nucleotide selectivity of the upstream PPRs.

Insights from the Molecular Modelling and Docking Analysis of AIF-NLS complex to infer Nuclear Translocation of the Protein.

Apoptosis Inducing Factor protein has a dual role depending on its localization in mitochondrion (energy production) and nucleus (induces apoptosis). Cell damage transports this protein to nucleus which otherwise favors mitochondrion. The alteration of Nuclear Localisation Signal tags could aid nuclear translocation. In this study, apoptosis inducing factor protein (AIF) was conjugated with strong NLS tags and its binding affinity with Importin was studied using in silico approaches such as molecular modeling and docking. This aims to improve the docking affinity of the AIF-Importin complex thus allowing for nuclear translocation, in order to induce caspase-independent apoptosis of the cell.