Fig 2. Schematic sequence alignment of COX1 and COX2 with two different gene configurations.

Amino-acid identities are highlighted with colors. COX1, COX2 and COX1/2 regions are indicated by green, yellow and blue boxes. Intron positions are represented by a discontinuity in the boxes. Any recognizable homing endonuclease domain, LAGLIDADG domain and/or GIY-YIG domain found within the hypothetical proteins encoded by the intronic ORFs are depicted by the letters H, L and G, respectively. The amino-acid sequences were aligned using MUSCLE with the default settings in Geneious 9.1.2. The detailed alignment is found in S2 Fig.