Fig. 9.

Retained exons of GNAO after 3R WGD in Teleostei. a A ML tree of exon7 and 8 nucleotide sequence indicates which exon pairs were retained across different Teleostei. Branches tested for positive selection are marked by ‘#’ and ‘*’. b After the 3R WGD, only one gene copy of GNAO (named copy ‘a’) maintained two sets of the mutually exclusive exon7–8 endings (variant ‘.2’ – blue, variant ‘.1’ – red). In Atlantic cod, both gene copies possess only one set of the final exons which was identified as the ‘.1’ variant. In both species of pufferfish, only the ‘b’ copy of GNAO was retained with the ‘.1’ exon variant