Arabidopsis Thaliana PPR Protein PDM1 Is Directly Involved In Splicing And Editing Of Chloroplast RNA

Most mature chloroplast m RNAs come from larger precursors through several posttranscriptional processing events, and PPR proteins have an irreplaceable function in these processing. PDM1, a PLS-type PPR protein, was suggested to be responsible for the cleavage of rpo A transcripts and the editing of most plastid editing sites in the previous research. However many questions about how does it work remain to be explained. In this research, we perform a co-immunoprecipitation mass spectrometry experiment to screen the proteins associated with PDM1. We obtain 126 non-redundant proteins that can be mostly classified into the category of RNA metabolism, protein metabolism and stress responding. By RNA immunoprecipitation experiment, we find that PDM1 associate with acc D-1 transcripts to involve in its editing. We confirm the direct interactions between PDM1 and editing factors, such as MORF2, MORF8, MORF9. Furthermore, we find that PDM1 involves in the group II intron splicing of trn K and ndh A transcript. We also discover that the pdm1 mutant show significant ROS accumulation. Taken together, our results suggest that PDM1 associates with multi-posttranscriptional regulation and translation.