title: Toxicogenomic analysis suggests chemical-induced sexual dimorphism in the expression of metabolic genes in zebrafish liver.
abstract: Differential gene expression in two sexes is widespread throughout the animal kingdom, giving rise to sex-dimorphic gene activities and sex-dependent adaptability to environmental cues, diets, growth and development as well as susceptibility to diseases. Here, we present a study using a toxicogenomic approach to investigate metabolic genes that show sex-dimorphic expression in the zebrafish liver triggered by several chemicals. Our analysis revealed that, besides the known genes for xenobiotic metabolism, many functionally diverse metabolic genes, such as ELOVL fatty acid elongase, DNA-directed RNA polymerase, and hydroxysteroid dehydrogenase, were also sex-dimorphic in their response to chemical treatments. Moreover, sex-dimorphic responses were also observed at the pathway level. Pathways belonging to xenobiotic metabolism, lipid metabolism, and nucleotide metabolism were enriched with sex-dimorphically expressed genes. We also observed temporal differences of the sex-dimorphic responses, suggesting that both genes and pathways are differently correlated during different periods of chemical perturbation. The ubiquity of sex-dimorphic activities at different biological hierarchies indicate the importance and the need of considering the sex factor in many areas of biological researches, especially in toxicology and pathology.
authors.affiliation: NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore, Singapore. g0801800@nus.edu.sg
authors.forename: Xun
authors.initials: X
authors.lastname: Zhang
authors.forename: Choong Yong
authors.initials: CY
authors.lastname: Ung
authors.forename: Siew Hong
authors.initials: SH
authors.lastname: Lam
authors.forename: Jing
authors.initials: J
authors.lastname: Ma
authors.forename: Yu Zong
authors.initials: YZ
authors.lastname: Chen
authors.forename: Louxin
authors.initials: L
authors.lastname: Zhang
authors.forename: Zhiyuan
authors.initials: Z
authors.lastname: Gong
authors.forename: Baowen
authors.initials: B
authors.lastname: Li
mesh_terms: D000818:Animals; D016000:Cluster Analysis; D005260:Female; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation / Q000187:drug effects; D053263:Gene Regulatory Networks; D023281:Genomics; D008099:Liver / Q000378:metabolism*; D008297:Male; D053858:Metabolic Networks and Pathways / Q000235:genetics*; D012727:Sex Characteristics; D015027:Zebrafish / Q000235:genetics* / Q000378:metabolism