Development of Platform Technology for Sterile Control
of Genetically Modified Fish
○Shao-Yang Hu1, Hong-Yi Gong1, Erez Raz2, Koichi Kawakami3,
Gen-Hwa Lin1, Jen-Leih Wu1
1) Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan,
2) Germ Cell Development, Max Planck Institute for Biophysical Chemistry, Gottingen, Germany,
3)Division of Molecular and Developmental Biology, National Institute of Genetics, Mishima, Japan
Since the 1985 when the first transgenic fish was successfully
established, the transgenic fish of various species are being actively
investigated worldwide for improving the economic benefit in aquaculture.
However, no any transgenic fish had been sold on the market to date except
the ornamental fish. The main impediment to commercialize the transgenic
fish is unfinished assessment of food safety and ecology impacts. The
ecological impacts focus on the issues concerning gene flow and the escape
of transgenic fish which may cause the extinction of wild natural fish stocks.
In view of this issue, sterile control turn into a core technology to solve
the theme of aquatic genetically modified organism release to the natural
environment. In the present study, we use zebrafish as model to establish a
sterile platform by ablation of primordial germ cells (PGCs) and oocytes.
Here, a 5 kb askopos (kop) promoter with PGCs specificity and a 2.2 kb
zona pellucida (zpc) promoter with oocytes specificity were cloned to
trigger KillerRed expression and the transgenic lines called kop:KillerRed
and zpc:KillerRed were established. KillerRed is a red fluorescent protein
capable of generating reactive oxygen species (ROS) upon light irradiation
and leading to cell apoptosis. The deficient gonad or undeveloped offspring
were shown in zpc:KillerRed transgenic line after light irradiation. The
fish without gonad was obtained in kop:KillerRed after ablation of PGCs
using red light irradiation. In contrast to the transgenic fish irradiated
with light, the development of gonad is normal in transgenic fish without
light irradiation. These results provide an inducible platform to control
the infertility of GM fish and offer economic benefits for maintenance of
superior breeds in aquaculture purpose.