Figure 5.

SSR using an inducible system based on fusion of β recombinase and the androgen receptor. (A) Scheme showing the retroviral vectors used in the inducible system. LZR-β-EGFP-(AR)LBD vector expresses the triple fusion protein (β-EGFP-LBD) of β recombinase, EGFP and the androgen receptor LBD (upper); the lower panel shows LZR-β-(AR)LBD-ires-EGFP vector which allows independent expression of the β-LBD fusion protein and EGFP by an IRES. Arrows indicate transcription units. (B) C7, C8 and C10 clones were transduced with the retroviral vectors and the EGFP-positive subpopulation selected by cell sorting. Western blot shows expression of β-EGFP-LBD (80 kDa), β-LBD (54 kDa), EGFP (27 kDa), and tubulin (control, 55 kDa) in transduced cells, untreated (−) or treated with (+) mibolerone (Mib; 10⁻⁸ M, 48 h). Non-specific bands are marked with an asterisk on the membranes. (C) Immunocytochemistry of β-LBD-ires-EGFP-expressing cells, alone or mibolerone-treated. (D) Immunocytochemistry of β-EGFP-LBD-transduced cells, alone or with mibolerone. Only data obtained in clone C8 have been included in (B–D). Clones C7 and C10 rendered quite similar results.