FIG. 4.
Half-life analysis of GFP-IL-6 constructs by the Tet-Off method in mouse NIH 3T3 cells. (A) GFP-IL-6 constructs were cloned in a retroviral vector behind a 7× Tet operator and induced with a tetracycline-sensitive transactivator protein, tTA (17). The transcription activator was then specifically blocked by the tetracycline analogue doxycycline (Dox). The hatched squares indicate a 19-nucleotide linker sequence which replaces the natural sequence at this position. Gray squares indicate the position of the putative stem-loop region, and black squares are the positions of AUUUA sequences. T1/2, half-life. (B) The GFP half-life was measured by real-time PCR and normalized to that of mARP0 mRNA (30).