FIGURE 1.

Activation of AR Leu⁷⁰¹ mutants by DHT. A, transcriptional responses of wild-type (WT) AR and AR Leu⁷⁰¹ mutants to DHT (100 nm). The single-letter amino acid code of the Leu⁷⁰¹ substitution is indicated on the x axis. Hep3B cells were transiently cotransfected with AR expression constructs and the (ARE)₂TATA-Luc reporter. Transcriptional activation of wild-type AR by DHT was set to 100%. Error bars represent mean relative luciferase activities of three independent experiments performed in duplicate (±S.E.). B, Western blot analysis showing protein expression of the AR Leu⁷⁰¹ mutants. C, dose-response curves of wild-type AR (black), AR L701I (blue), and AR L701F (red) with DHT. Hep3B cells were transiently transfected as described above and incubated for 24 h with the indicated concentrations of DHT. The response of wild-type AR to 100 nm DHT was set at 100%. Data represent the mean relative luciferase activities of three independent experiments performed in duplicate (±S.E.). D and E, structural representations of the wild-type AR LBD in complex with DHT showing the relative position of Leu⁷⁰¹ in the ligand-binding pocket. The steroidal 3-keto and 17β-OH groups are indicated. Dotted red lines represent hydrogen bonds.