An mGlu4 RNA duplex composed of exonic sequence is sufficient for editing. (A) Predicted mGlu4 RNA duplex generated using mfold, composed of nucleotides 729–855 (Human, NM_000841.4), and 1132–1258 (Rat, NM_022666.1). (B) Editing of rat and human cDNA constructs cotransfected into HEK293T cells with either empty vector, ADAR1, or ADAR2. Editing can be seen by the dual “A” and “G” chromatogram peaks. (C) Predicted rat mGlu4 duplex expressed as a minigene cotransfected into HEK293T cells ± ADAR1, ADAR2, or vector control. Editing percentages are calculated by measuring the peak heights of Sanger sequencing chromatogram peaks. Mean ± S.E.M. n = 4. Q124R and K129R editing site positions within the duplex are denoted by blue and gray colors, respectively. The nucleotide sequence on the opposing side of the proposed duplex to the editing site (outlined in red hashes) was mutated (mutant sequence highlighted solid red) to destabilize the structure. The nucleotide sequence surrounding the editing site (outlined in green) was mutated (mutant sequence in solid green) with compensatory changes to restabilize the RNA duplex.
