Figure 3

DNA and transgene expression analysis of F1 progeny from transgenic founder Tg144. A. Southern blot analysis. Samples of genomic DNA from Tg144 and its F1 progeny were digested with EcoRI and hybridized with rtTA-M2 cDNA. Founder (F0) and first generation progeny (F1) identification numbers are indicated at the top of each lane. Four different transgene integration patterns were passed to the F1 progeny of transgenic founder Tg144 and are identified by letter at the bottom of each lane (a, b, c, d). F1 progeny carried one to four integrations of the rtTA-M2 transgene. B. Fibroblasts from F1 progeny with each of the four integration patterns were transduced with Lenti-TetO₇/CMV-EGFP and cultured with or without Dox (Dox +/-). EGFP expression was evaluated by Western blot analysis 48 hours after viral transduction. The blot was stripped and reprobed with β-actin antibody as a loading control.