FGF21 as an Endocrine Regulator in Lipid Metabolism: From Molecular Evolution to Physiology and Pathophysiology
Figure 1
The evolutionary lineage of deuterostome organisms and the evolutionary history of endocrine Fgf genes. (a) The Fgf gene family expanded in two major phases (I and II) during deuterostome evolution. Phase I occurred after the separation of protostomes and deuterostomes. Phase II occurred early in the emergence of vertebrates. (b) Fgf13-like is the ancestral gene of the Fgf gene family. Fgf4-like was generated from Fgf13-like by gene duplication during invertebrate evolution. Fgf15/19-like was also generated from Fgf4-like by local gene duplication early in the emergence of vertebrates. Later, Fgf19, Fgf21, and Fgf23 were generated via two genome duplication events in phase II.
