TetR Monoclonal Antibody (Clone 9G9) is a monoclonal antibody raised against the full-length wild-type bacterial Tet repressor protein (TetR), which is an essential component of the Tet-On and Tet-Off transactivator proteins. The TetR antibody can be used for Western blotting and greatly simplifies the process of developing a Tet-inducible expression system by providing a method for early detection of the transactivator proteins.