Expression and phylogeny of candidate genes for sex differentiation in a primitive fish species, the Siberian sturgeon, Acipenser baerii

• Published in: Molecular Reproduction and Development
• Main Authors: Berbejillo, Julio, Martinez-Bengochea, Anabel, Bedo, Gabriela, Brunet, Frédéric, Volff, Jean-Nicolas, Vizziano-Cantonnet, Denise
• Other Authors: Universidad de la República Montevideo (UDELAR), Institut de Génomique Fonctionnelle de Lyon (IGFL), École normale supérieure - Lyon (ENS Lyon)-Institut National de la Recherche Agronomique (INRA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Programa de Desarrollo Tecnologico del Uruguay 71-13
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2012
• Subjects: TILAPIA OREOCHROMIS-NILOTICUS; DM-DOMAIN GENE; RAINBOW-TROUT; GONADAL DIFFERENTIATION; ONCORHYNCHUS-MYKISS; TELEOST FISH; SEQUENCE ALIGNMENT; DETERMINING REGION; OVARY DEVELOPMENT; I MESSENGER-RNA; [SDV]Life Sciences [q-bio]; [INFO]Computer Science [cs]; Acipenser baerii; Siberian sturgeon
• Online Access: https://hal.inrae.fr/hal-02648716; https://doi.org/10.1002/mrd.22053

International audience The molecular mechanisms underlying testis differentiation in basal actinopterygian fish remains poorly understood. The sex differentiation period was investigated in the Siberian sturgeon, Acipenser baerii, by expression profiling of Sertoli cell transcription factors (dmrt1, sox9) that control testis differentiation in vertebrates; Leydig cell factors (cyp17a1, star) affecting androgen production; the androgen receptor (ar); a growth factor controlling testis development (igf1); and a gene coding for a gonadotropin hormone (lh). Two genes were characterised for the first time in the Siberian sturgeon (dmrt1, cyp17a1), while the others came from public databases. Sturgeon gonad development is very slow, with a late sexual differentiation time during their juvenile stage, and are still immature at 3 years of age. Immature fish showed a sex-dimorphic pattern; all the genes studied displayed a higher expression level in male gonads. We took advantage of the presence of juvenile fish with pre- and post-differentiated gonads (16 and 18 months old) to characterise them at the molecular level. The post-differentiated fish displayed a sex dimorphism of gene expression in their gonads for all genes studied, with the exception of sox9. The trends in undifferentiated fish lead us to propose that sturgeons undergoing male differentiation express high levels of Sertoli cell factors (dmrt1, sox9) and of genes involved in the production and receptivity of androgens (cyp17a1, star and ar) together with lh. Expression profiles and phylogenetic studies suggest that these genes are potential regulators of testis development in the Siberian sturgeon.Mol. Reprod. Dev. 79: 504-504, 2012. (C) 2012 Wiley Periodicals, Inc.