Fig. 1: Sequence and post-transcriptional modifications of human mt-Leu(UAA).

a Sequence and cloverleaf structure of human mt-Leu(UAA) showing the A3243G and T3271C substitutions in blue and the m1G9 and τm5U34 modifications in red, both mapped to the canonical L-shaped tRNA structure. b Chemical structure of m1G, showing the N1-methyl group in red. c Chemical structure of τm5U, showing the taurine-C5-methyl group in red.