An Ecdysone-Inducible Expression System for Use with Retroviruses

Gene expression systems that can be induced or regulated are particularly useful when the gene of interest is toxic to the cell, or when the amount of protein expressed needs to be tightly controlled, such as for gene therapy. Many systems are available that achieve high levels of induced gene expression while maintaining low basal expression in the absence of inducer. These systems vary, however, in levels of induction obtainable, toxicity of the drug or hormone used for induction, and kinetics of induction or repression.