Analysis of RNA editing sites in ADAR1 KI/ADAR2 KO mice. Mus musculus

Adenosine-to-inosine RNA editing is catalyzed by ADAR1 and ADAR2 in mammals. Although both ADAR1 KO mice and ADAR1 KI mice that harbor the editing-inactive E861A point mutation are embryonically lethal, this lethality can be rescued by concurrent deletion of MDA5. ADAR2 KO mice are also lethal during early postnatal stage, whereas this lethality can be rescued by insertion of a point mutation at the Q/R site of the glutamate GluA2 subunit to express edited GluA2 solely. Given that RNA editing is catalyzed by ADAR1 and ADAR2 either cooperatively or competitively, it is important to know whether RNA editing completely disappears by deletion of both ADAR1 and ADAR2 and its phenotypic consequences. Therefore, in this study, we created Adar1/Adar2 double mutant mice to examine whether RNA editing would completely disappear.