The T-REx™ System yields higher levels of induced expression than any other regulated mammalian expression system. It utilizes the complete CMV promoter and adds control elements from the bacterial tetracycline resistance operon to effectively repress and derepress transcription from one of the strongest mammalian promoters known.  

Life Technologies offers a selection of T-REx™ products, including expression vectors and systems as well as cell lines that stably express the tetracycline repressor protein. These cell lines exhibit extremely low basal expression levels in the repressed state and high expression upon induction with tetracycline.