Involved in multiple sites RNA editing events in chloroplasts. Involved in the editing of the site 7 of ndhB (ndhB-7) and site 5 of ndhD (ndhD-5) transcripts, which are two plastid-encoded subunits of the chloroplast NAD(P)H dehydrogenase (NDH) complex. Involved in the editing of the site 3 of rpoB (rpoB-3) transcript. Required for the activity of the NDH complex of the photosynthetic electron transport chain. Possesses low endoribonuclease activity in vitro. Impaired chloroplastic NAD(P)H dehydrogenase (NDH) activity. The DYW motif is dispensable for editing activity in vivo. Belongs to the PPR family. PCMP-H subfamily.