Characterization of gene trap and enhancer trap transgenic zebrafish lines that express Gal4 in specific region of brain in adult stage
○Pradeep Lal, Koichi Kawakami
We have developed the Gal4-UAS system and Gal4 gene trap and enhancer trap methods by using the Tol2 transposon system in zebrafish. We isolated transgenic fish lines that express the Gal4 transactivator in specific tissues. By crossing these Gal4 lines with the UAS-GFP line, it is possible to visualize the Gal4-experssing cells.
We found fish lines that showed Gal4 expression in the central nervous system. We analyzed transgenic fish lines for specific expression patterns in different regions of the brain in adult stages. To date, we observed 243 transgenic lines and identified 14 adult fish lines with strong and specific Gal4 expression in the brain. We further analyzed those fish by Southern blot hybridization and inverse PCR, and identified the integration sites of the Tol2 constructs. We will discuss here the Gal4 expression pattern and the trapped genes in these transgenic fish lines.
These Gal4 lines will be useful to analyze regionalization of the brain and to discover marker genes that can label specific cell types. Also, by crossing these lines with the UAS-tetanus toxin fish line, it is possible to inhibit the function of Gal4 expressing neurons. This strategy can be used to dissect neuronal circuits involved in specific behaviors.