Gerety, S.S., Breau, M.A., Sasai, N., Xu, Q., Briscoe, J., and Wilkinson, D.G. (2013) An inducible transgene expression system for zebrafish and chick. Development (Cambridge, England). 140(10):2235-2243.
We have generated an inducible system to control the timing of transgene expression in zebrafish and chick. An estrogen receptor
variant (ERT2) fused to the GAL4 transcriptional activator rapidly and robustly activates transcription within 3 hours of
treatment with the drug 4-hydroxy-tamoxifen (4-OHT) in tissue culture and transgenic zebrafish. We have generated a broadly
expressed inducible ERT2-GAL4 zebrafish line using the ubiquitin (ubi) enhancer. In addition, use of ERT2-GAL4 in conjunction with tissue-specific enhancers enables the control of transgene expression
in both space and time. This spatial restriction and the ability to sustain forced expression are important advantages over
the currently used heat-shock promoters. Moreover, in contrast to currently available TET and LexA systems, which require
separate constructs with their own unique recognition sequences, ERT2-GAL4 is compatible with the growing stock of UAS lines
being generated in the community. We also applied the same inducible system to the chick embryo and find that it is fully
functional, suggesting that this strategy is generally applicable.