Polyploidization and pseudogenization in allotetraploid frog Xenopus laevis promote the evolution of aquaporin family in higher vertebrates

Aquaporins (AQPs), as members of the major intrinsic protein (MIP) superfamily, facilitated the permeation of water and other solutes and are involved in multiple biological processes. AQP family exists in almost all living organisms and is highly diversified in vertebrates in both classification and function due to genome wide duplication.