Hemizygous transgenic mice are viable, fertile, normal in size, and do not display any gross physical or behavioral abnormalities. These mice express the rtTA transgene under the control of the rat nestin intron II enhancer/promoter. Expression occurs in the neuroepithelium of the developing nervous system (embryonic days 10-17), in some neuron subsets of the adult mouse, for example, the cerebellum, hippocampal dentate gyrus, subventricular zone, spinal cord), and in adult testes.

When Tg(Nes-rtTA)306Rvs hemizygous mice are mated to a second transgenic strain carrying a gene of interest under the regulatory control of a tetracycline-responsive promoter element (TRE), expression of the target gene may be regulated by the tetracycline analog, doxycycline (dox). In the presence of dox, transcription of the target gene is induced in cells where rtTA is expressed.