Transcriptomics of Fish Sex Differentiation

• Main Authors: Piferrer, Francesc, Ribas, Laia, Sánchez Baizán, Núria, Anastasiadi, Dafni, Valdivieso, Alejandro
• Other Authors: Ministerio de Economía y Competitividad (España)
• Format: Conference Object
• Language: unknown
• Published: 2017
• Subjects: Scophthalmus maximus; Turbot
• Online Access: http://hdl.handle.net/10261/179117; https://doi.org/10.13039/501100003329

Plant and Animal Genomics (PAG) Asia, 29-31 May 2017, Seoul, South Korea One way to increase the production of farmed fish is through exploitation of the fact that in many species one sex, usually females, grows faster than the other. Thus, for the production of monosex stocks, it is necessary first to understand the process of sex differentiation in fish in order to achieve its control. Here, using a tropical species (zebrafish, Danio rerio), a temperate water species (European sea bass, Dicentrarchus labrax) and a cold water species (turbot, Scophthalmus maximus), we investigated common patterns of gene expression during sex differentiation and in response to heat. The genes and signaling pathways involved in ovarian and testicular differentiation are fairly conserved albeit with species-specific differences in their interaction and/or temporal expression. Likewise, exposure to heat has only moderate effects on males and the testis transcriptome. In contrast, elevated temperature can result in genetic females developing functional testis (neomales) with a normal male transcriptome and capable of producing viable sperm. This represents a mismatch between genotype and phenotype. In species with a simple chromosomal system of sex determination like the turbot (ZW/ZZ), neomales can be used to generate novel genotypes (WW, superfemales) to obtain the desired all-female stocks. Recently, we discovered that some heat-exposed zebrafish females have apparently normal ovaries but with a male transcriptome (pseudofemales). In this case, the mismatch is between form and function. However, the fate of pseudofemales, including whether they can produce viable gametes and of what sex is, at present, unknown Supported by MINECO AGL2016-78710-R grant to FP. Peer Reviewed