Finally, we carried out qRT-PCR to explore the expression profiles of khdrbs in adult zebrafish (Figure 10 and Supplementary Figure 2). As shown in Figures 10A,B, both khdrbs1a and khdrbs1b shared similarities in their expression profiles. They were both detected in all the tissues tested, with the highest expression levels in the brain. The obvious difference between khdrbs1a and khdrbs1b was that the latter gene had higher expression in the gonads. In contrast, the expression of khdrbs2 and khdrbs3 became more distinct: both khdrbs2 and khdrbs3 signal was predominantly detected in the brain, with lower expression in the eye and testis (Figures 10C,D). These indicated that these genes are mainly expressed in the brains of adult zebrafish in a tissue-specific fashion, consistent with their expression patterns in embryogenesis.