Figure 8.

Scenario for the evolution of the gph-related gene environments. The chordate gpa-gpb locus was duplicated prior to the first round of genomic duplication and the newly created gphβ was transferred to vertebrate proto-chr D whereas gpa2, gpb5 and gphα localized on vertebrate proto-chr. G. Paralogues of gpa2-gpb5-gphα and gphβ environments were then created through two whole genome duplications (WGD). Genes that have been lost are crossed out in red. Gpb5a is still present in teleosts in [GPA2] environment but was lost in tetrapods (see Figure 9).