Table 1.

RNA editing in different genetic systems in the chronological order of their discoveries

Date	Organisms	Type of RNA editing	Affecting	In genetic system	Original discoveries
1986	Kinetoplastids	U insertions, U deletions	Diverse mRNAs	Mitochondrial	Four uridines inserted into the mitochondrial cox2 mRNA of Trypanosoma brucei and Crithidia fasciculata to reconstitute the reading frame [1]
1987	Mammals	C to U	Some mRNAs and viral RNAs	Nuclear	Stop codon introduced by conversion of glutamine codon in apoB mRNA in human intestine [41–43]
1988	Paramyxoviruses	G and A insertions	P (phosphoprotein) and glycoprotein mRNAs	Viral	Insertion of two guanosine nucleotides in Sendai virus 5 (SV5) phosphoprotein (P) mRNAs establishing a new reading frame [64]
1989	Plants	C ↔ U	mRNAs, tRNAs (rRNAs)	Mitochondrial	Multiple codon sense changes by C-to-U conversions observed in mitochondrial mRNAs in wheat Triticum aestivum [72, 73] and in the evening primrose Oenothera berteriana [74]
1991	Plants	C ↔ U	mRNAs, tRNAs (rRNAs)	Chloroplast	The start codon of the maize Zea mays chloroplast rpl2 gene introduced via C-to-U RNA editing of a genomically encoded ACG threonine codon [92]
1991	Myxomycota	C insertions, U insertions, dinucleotide insertions, C to U	mRNAs, rRNAs, tRNAs	Mitochondrial	Multiple C insertions in the mitochondrial atp1 mRNA in Physarum polycephalum [165]
1991	Metazoa	A to I (G)	Many mRNAs, tRNAs, miRNAs, and viral RNAs	Nuclear	An apparent glutamine CAG to arginine CGG codon change in the mRNA of glutamate-gated ion channels in mouse brain [187]
1993	Acanthamoeba and chytridiomycete fungi	N to N′	tRNA 5′ acceptor stem	Mitochondrial	Different nucleotide exchanges in the first three nucleotides of tRNAs initially found in Acanthamoeba castellanii [210], later in Spicellomyces punctatus [214]
1993	Marsupials	C to U	tRNA anticodon	Mitochondrial	The genomically encoded GCC anticodon sequence of trnD, the tRNA for aspartate is corrected to the GUC anticodon in 50% of tRNAs in mitochondria of the opossum Didelphis virginiana [219]
2002	Dinoflagellate	A ↔ G, C ↔ U, U to R, G to C	mRNA	Mitochondrial	Nucleotide substitutions in mitochondrial cob and cox1 mRNAs of Pfiesteria piscicida, Prorocentrum minimum, and Crypthecodinium cohnii [237]
2004	Dinoflagellate	A ↔ G, C ↔ U, R to C, U to G	mRNA, rRNA	Chloroplast	Nucleotide substitutions in several chloroplast mRNAs and in the small rRNA in Ceratium horridum [238]
2009	Archaeae	C to U	tRNAs	Bacterial	Conserved uridine in tRNA consensus position 8 re-established via deamination in tRNAs of the thermophilic archaeon Methanopyrus kandleri [245]
2009	Placozoa	U to C	mRNA	Mitochondrial	A U-to-C conversion transforming a tyrosine into a histidine codon in the mitochondrial cox1 mRNA in Trichoplax adhaerens [244]