A transgenic zebrafish model of targeted oocyte ablation and de novo oogenesis

We describe here a novel transgenic zebrafish, Tg(zpc:G4VP16/UAS:nfsB‐mCherry) that effectively demonstrates the targeted oocyte ablation in the adult zebrafish ovary. This transgenic line expresses bacterial nitroreductase enzyme (nfsB) under the control of the oocyte‐specific zona pellucida C ( zpc ) gene promoter. Adult transgenic females exposed to the prodrug metronidazole demonstrated near‐complete ablation of growing oocytes, resulting in ovarian degeneration and complete cessation of reproductive function. Within 4 weeks of prodrug removal, treated fish demonstrated complete anatomical regeneration of the ovary and, within 7 weeks, ovarian function (fertility) was fully restored. Together, these results demonstrate functional renewal of the oocyte pool in the adult zebrafish ovary. Accordingly, this transgenic zebrafish model system provides a novel means to investigate ovarian growth dynamics in a genetically tractable vertebrate, and may be useful for evaluating signaling interactions that regulate gonadal development processes such as de novo oogenesis. Developmental Dynamics 240:1929–1937, 2011. © 2011 Wiley‐Liss, Inc.