Figure 3
(a) Expression patterns of sex steroid biosynthesis-related genes in gonads of Pacific bluefin tuna at the sex differentiated stage. The diagram shows gonadal sex steroid biosynthesis pathways in fish26,27. Upregulated genes in females and males are indicated by red and blue boxes, respectively (P < 0.05). Genes not significantly different between sexes are indicated by gray boxes (P > 0.05). The gene with no detectable expression is indicated by a white box. Expression patterns of genes encoding 17β-hydroxysteroid dehydrogenases (17β-HSDs) are shown in Supplementary Fig. S1. (b) Temporal expression patterns of genes encoding key enzymes in estrogen and androgen biosynthesis during gonadal sex differentiation in Pacific bluefin tuna. Total RNA extracted from gonads in each sex at morphologically sex-undifferentiated (41 days post-hatching (dph)), differentiating (57 dph), and differentiated (83 dph) stages6 subjected to quantitative real-time reverse transcription PCR. Open and closed circles indicate genotypic females and males, respectively. Bars indicate mean ± standard error of the mean (SEM) (n = 3 fish). Different letters indicate significant differences (P < 0.05, one-way ANOVA followed by Tukey’s multiple comparisons test). Asterisks indicate significant differences between sexes at each age (P < 0.05, Welch’s t-test). Cyp19a1a expression data were previously reported1.
