Effect of Doxorubicin on abcb4 Gene Expression in Zebrafish (Danio rerio) Embryos

To determine the effect of doxorubicin (DOX) on abcb4 gene expression and the role of abcb4 gene in multidrug-resistance.Zebrafish embryos were treated with 2 mL/L DMSO, 10 μmol/L DOX and 2 mL/L DMSO+10 μmol/L DOX, respectively. The zebrafish embryos treated with Eggwater served as controls. Exposures started at 4 to 16 cell stage of the embryos and terminated 120 hours post fertilization (hpf). The expression of abcb4 gene in zebrafish embryos was examined on 48, 72, 96, and 120 hpf with whole-mount in situ hybridization (WISH) and quantitative real-time PCR (qPCR).Compared with the controls, DOX-exposed embryos had higher level of abcb4 gene expression (P < 0.05), but not for abcb5 gene. WISH showed that abcb4 gene was expressed in the guts of zebrafish embryos. However, those exposed to DOX also showed strong WISH signals in the brain and heart.Doxorubicin increases the expression of abcb4 gene in zebrafish embryos. abcb4 gene may play an imoortant role in multidrug-resistance.