Identification of sexually dimorphic gene expression in the brain of adult zebrafish (Danio rerio)

ABSTRACT: Sexual differentiation in vertebrates is initiated during embryogenesis and leads to the development of individuals into phenotypic males or females. The molecular pathways showing sexual dimorphic patterns have been principally investigated in the gonads. In other organs, much less is known about the gender-associated pattern of gene expression. The brain plays a coordinating role on sexual function in both genders including regulation of reproductive development and maturation through the synthesis of neuropeptide hormones and the regulation of sexual behavior in both males and females. In this study, we aimed at identifying molecular pathways regulated in a gender specific manner in breeding zebrafish in order to generate a greater understanding of the gender specific physiology of the brain. To do so, we measured the gene expression profiles of individual brains of 6 males and 5 females using a 17k oligonucleotide microarray, and interrogated the dataset for genes showing a gender-specific gene expression profile. 42 genes were found to be differentially expressed between males and females from which 18 genes were over-expressed in males and 24 genes were over-expressed in females. Sexually mature fish (6 males and 6 females) were kept in a 15L tank and allowed to breed naturally. After a 20-day period, fish were sacrificed humanly and the brain was extracted, fixed in RNAlater (Ambion) and stored at -20oC until required for microarray analysis. RNA was extracted using the TRI reagent method followed by a LiCl precipitation (Sigma) according to the manufacturer's instructions. Total RNA was amplified and labeled using the Amino Allyl MessageAmp aRNA amplification kit (Ambion). A reference design was used for the array hybridizations. Array analysis was performed according to established protocols (described in Santos et al., 2007) and the data was extracted and queried for differences in gene expression profiles between genders.

ORGANISM(S): Danio rerio

SUBMITTER: Eduarda Santos 

PROVIDER: E-GEOD-6853 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress