title: The 17beta-hydroxysteroid dehydrogenase 4: Gender-specific and seasonal gene expression in the liver of brown trout (Salmo trutta f. fario).
abstract: Previously, it was documented that liver peroxisomes display seasonal size changes in the adult Salmo trutta fario, especially in females (and negatively correlated with ovary maturation). It was then hypothesized that decreases in peroxisome size could be paralleled by changes in peroxisomal beta-oxidation and estradiol catabolism actions. The 17beta-hydroxysteroid dehydrogenase 4 has been portrayed as playing an important role in both processes. To elucidate its function in the described peroxisomal pattern, we isolated the cDNA and predicted the protein sequence of the enzyme in that species. The seasonal gene expression pattern in both genders was addressed through quantitative PCR. Fish sampling was in post-spawning period, early and advanced gonad maturation, and pre-spawning. Males did not vary seasonally. As to females, a seasonal pattern was evidenced according to our previous hypothesis. We suggest that the decreased levels observed during vitellogenesis are related to lipid needs for ovary maturation, and, additionally, with the need of modulating estradiol titers.
authors.affiliation: CIIMAR - Interdisciplinary Centre of Marine and Environmental Research, CIMAR Associate Laboratory, UPorto - University of Porto, Laboratory of Cellular, Molecular and Analytical Studies, Rua dos Bragas 289, 4050-123 Porto, Portugal.
authors.forename: L Filipe C
authors.initials: LF
authors.lastname: Castro
authors.forename: Maria J
authors.initials: MJ
authors.lastname: Rocha
authors.forename: Alexandre
authors.initials: A
authors.lastname: Lobo-da-Cunha
authors.forename: Carla
authors.initials: C
authors.lastname: Batista-Pinto
authors.forename: Ana
authors.initials: A
authors.lastname: Machado
authors.forename: Eduardo
authors.initials: E
authors.lastname: Rocha
mesh_terms: D015067:17-Hydroxysteroid Dehydrogenases / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D005260:Female; D029941:Fish Proteins / Q000235:genetics / Q000378:metabolism*; D008055:Lipids / Q000502:physiology; D008099:Liver / Q000201:enzymology; D008297:Male; D008969:Molecular Sequence Data; D010802:Phylogeny; D012621:Seasons; D012737:Sex Factors; D014337:Trout / Q000378:metabolism*
chemical_list: D029941:Fish Proteins; D008055:Lipids; D015067:17-Hydroxysteroid Dehydrogenases; C044256:3 (or 17)-beta-hydroxysteroid dehydrogenase