Disease-associated mutations in human mitochondrial aaRSs. (A) Schematic representation of domain architecture of mitochondrial aaRSs in which disease-associated substitution mutations have been identified. Catalytic domain and anticodon binding domain are in blue and cyan respectively. Domain boundaries for aaRS sequences were calculated using Pfam server. (B) Mutations (red) in cytoplasmic aaRSs mapped on the crystal structures where its domains have been color-coded corresponding to (A).