RNA editing sites were systematically examined for the transcripts of
74 known protein-coding genes in the chloroplasts of P. aphrodite. A total of
44 editing sites were identified in 24 transcripts, the highest number reported
in seed plants to date. In addition, 21 editing sites were unique to Phalaenopsis
as compared to other seed plants. All editing was C-to-U conversion, and
42 editing sites caused the change in amino acids. One of the remaining two
editing sites occurred in transcripts of the ndhB pseudogene, and another in
the 5’ untranslated region of psbH transcripts. However, RNA editing did not
restore the continuous open reading frame in the frameshifted ndh genes,
further confirming that they are pseudogenes.
