18February 2021

The role of stress and epigenetics in sexual fate in fishes

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Bannière des Jeudis

> Alexander Goikoetxea Post-Doctorant Ifremer, UMR MARBEC Palavas , JEUDI 18 FÉVRIER 2021, 13h45 \ 14h30

The role of stress and epigenetics in sexual fate in fishes

Sex change occurs as a usual part of the life cycle for many teleost fishes, is often socially-cued, and characteristically involves dramatic changes in behaviour, gonadal structure and gene expression. Even in some gonochoristic fish species (fixed separate sexes), there are instances where specific external conditions can induce functional sex reversal in otherwise GSD (genetic sex determination) species. The precise way in which environmental signals (e.g., social cues, temperature) are transduced into the molecular cascade that underlies these transformations remains unknown. Recent research implicates both the stress axis and epigenetic mechanisms as key factors linking environmental stimuli and the control of sexual fate. Here, we examine the role of cortisol (the main stress hormone in fish) and epigenetic factors in mediating this extraordinary example of sexual plasticity in a protogynous (female-to-male) hermaphrodite, the New Zealand spotty wrasse (Notolabrus celidotus). Social manipulation (removal of dominant males) is sufficient to induce sex change in captive females of this species. We also explore how thermal stressors of different magnitude and/or duration can affect sex differentiation during the early stages of development in the European seabass (Dicentrarchus labrax), a species of massive economic importance for the Mediterranean aquaculture and fisheries industries.
The conference’s video:

Jeudi 25 février 2021 : Camille Houdelet Post-Doctorante Ifremer, UMR MARBEC Palavas, "Des abeilles aux poissons !"

UMR MARBEC (IRD, Ifremer,Université de Montpellier, CNRS) ✆ 04 99 57 32 27 - 04 99 57 32 90 - 04 67 14 36 72 \ www.umr-marbec.fr



MARBEC MARine Biodiversity, Exploitation and Conservation, is a research unit which includes the staff of 4 organizations: IRD, IFREMER, UM and CNRS. Its objective is the study of marine biodiversity in lagoon coastal and offshore ecosystems, at different integration levels, molecular, individual, population and community aspects and the way humans use this biodiversity.