Embryonic beta-globin in the non-Antarctic notothenioid fish Cottoperca gobio (Bovichtidae)

Haemoglobins are sensitive to temperature and their properties mirror the thermal conditions encountered by species during their evolutionary histories. This paper provides data on molecular phylogeny of the haemoglobin chains of Cottoperca gobio, a notothenioid fish of sub-Antarctic latitudes, belonging to the basal family Bovichtidae. Unlike most Antarctic notothenioids, C. gobio has two major haemoglobins sharing the beta chain. In the molecular phylogenetic analysis, the beta chain is included in the clade of the "embryonic" or minor Antarctic globins. Although, in the majority of notothenioids, "embryonic" (minor) alpha and beta globins are expressed in traces or small amounts in the adult stage, in C. gobio the present analysis supports the occurrence of a complete "switch" to exclusive expression of the embryonic beta-globin gene in adult fish. The alpha and beta chains sequences have been used to expand our knowledge of the evolution of notothenioid haemoglobins