RNAs mensageiros (mRNAs) como indicadores da qualidade de gametas em peixes

Abstract

The quality of gametes in farmed broodstock is still highly variable and has been considered one of the major problems for the expansion of fish farming. The culture conditions, the environmental factors and the genetic and physiological parameters of the animals are factors that affect the gamete production and quality in farmed fish. In aquaculture, the use of high quality gametes is essential for the production of viable larvae, however, the evaluation of gamete quality is based only on basic characteristics of gametes. In males, the most common analysis used to evaluate sperm quality are motility, cell concentration and sperm morphology. In females, the determination of the rates of fertilization, hatching and normal larvae, as well as, the quantification of the total number of oocytes produced and oocyte diameter are the parameters used to evaluate egg quality. However, the recent advances in molecular biology applied to reproduction have allowed the discovery of paternal and maternal transcripts that are involved with gamete quality. Although these studies are still in ongoing in fish, these messenger RNAs (mRNAs), that are accumulated during the gametogenesis process and are involved in different cellular processes, seem to be essential for fertilization and successful embryo development. Thus, the aim of this study is to perform a literature review on the use of paternal and maternal transcripts as indicators of gamete quality in teleosts. The researches on paternal and maternal transcripts that have been performed especially in species such as zebrafish (Danio rerio), Atlantic cod (Gadus morhua), Atlantic halibut (Hippoglossus hippoglossus), sea bass (Dicentrarchus labrax), rainbow trout (Oncorhynchus mykiss), and Japanese eel (Anguilla japonica) might help in future studies with native Brazilian species.