MUP-tTA Mouse Model for Liver Function Studies
The E. Coli tetracycline operon regulatory system was used to generate a liver-specific transcription activation system that was inhibited by tetracycline. The transcription activator was a fused protein consisting of a tetracycline repressor gene (tetR) that was only active in the presence of tetracycline and a herpes simplex virus protein (VP-16) transcription activating domain (Tet-Off). Transcription was induced only in the absence of tetracycline (Tet-Off). A liver-specific promoter such as the mouse major urinary protein (MUP) promoter determined that the tetracycline-regulated transcriptional activator (tTA) would be expressed specifically in liver. To study the effect of the transcription activator on a target gene (for example, beta-galactosidase, LacZ) specifically in liver, MUP-tTA mice would be mated with transgenic mice in which the TAg Target gene was controlled by the E.Coli Tetracycline Operator (Tet-O). The Tet technology may require a separate license.