Project description:The domestication is an evolutionary process during which individuals will progressively adapt to an environment controlled by humans. It is accompanied by epigenetic and genetic modifications potentially leading to modifications in the transcriptomic profile in various tissues. The reproduction process is among the biological functions highly affected whatever the species and/or the way of domestication. Indeed, the reproduction success often decreases in domesticated populations. For fish, the molecular content of the eggs is crucial for the proper embryogenesis. Among these molecules the mRNA content depends directly from the gene expression and thus may reflect the genetic modifications occurring during this process. Here, we investigated the transcriptomic profile of eggs coming from females of two populations (F1 and Fx) that were reared in the same conditions and were genetically close. Our main goal was thus to determine how the domestication process may affect the reproduction success in the Eurasian perch and if it was mediated by the regulation of the transcription in the eggs. A regular follow up of the oogenesis progression showed few differences of the hormonal production between the two populations. Nevertheless, the histological study showed that the F1 females were more developed by the end of the oogenesis induction than the domesticated ones and as a result, they spawned earlier than the domesticated ones. The study of the early developmental success revealed significant differences between the populations. The microarray analysis of unfertilized eggs presented more than 350 transcripts differently expressed between the two populations. Among them, some specific genes were drastically more expressed in the domesticated (mex3B, hace1 and an uncharacterized protein) or F1 (per) populations. Our data show that the F1 population is more sensitive to the environmental conditions to advance oogenesis and reach the spawning season earlier. The transcriptomic profiles in eggs coming from the two populations were different and may lead to developmental impairments having a potential link with the domestication process. Further analyses are needed to explain these differences.
