Els mecanismes de regulació i els efectes de la temperatura en la diferenciació sexual del llobarro

Memòria de tesi doctoral presentada per Laia Navarro Martín per optar al grau de Doctora en Biologia per la Universitat de Barcelona (UB), realitzada sota la direcció del Dr. Francesc Piferrer i Circuns de l'Institut de Ciències del Mar (ICM-CSIC).-- 326 pagesThis Thesis has been carried out in the Group of Biology of the Reproduction (GBR) of the Department of Renewable Marine Resources at the Institute of Marine Sciences (ICM-CSIC) of Barcelona and under the tuition of the department of Physiology of the University of Barcelona during the period 2003-2008. The results obtained in these studies are not only important in sea bass, but also some of them can be generalized to other fish and vertebrates. The aim of this Thesis was to study sea bass sex differentiation at different levels: at endocrine level, analysing the influence of different steroids and agonists and antagonists compounds of the ovarian and testicular differentiation pathways; at expression level of some genes that are required for the necessities of the gonads to differentiate towards ovaries or testes; and also through mechanisms of epigenetic regulation, such as methylation, that may be responsible for the complex process of developing a bipotential tissue, like the undifferentiated gonad, into a ovary or testis. In non-mammalian vertebrates like some fishes, amphibians and reptiles, the mechanism by which the temperature can affect sex differentiation, and consequently the proportion of sexes, remains unknown. The results obtained in this thesis allow to propose an hypotheses about how temperature can be influencing sex differentiation and which mechanism can be responsible for that. In the present thesis, the sea bass has been used as model specie. However, and although these studies have broadened our knowledge in this field, the obtained results have posed new questions that can be resolved in future experiments. [...]Laia Navarro Martín was supported by a FPI fellowship (BES-2003-0006) from the Spanish Ministry of Education and SciencePeer Reviewe