FIG. 2.

Survey of FRT site-specific recombination. (A) PCR analysis. Genomic DNAs from BCBL-1 (lanes 1), Flp-In BCBL1 (lanes 2), TREx BCBL1 (lanes 3), TREx BCBL1-Rta (lanes 4), TREx BCBL1-vector (lanes 5), BJAB (lanes 6), and H₂O (lanes 7) were used for PCR amplification. PCR primers P1 to P9 are shown in Fig. 1 and Table 1. The arrows indicate appropriate PCR products. M, molecular size marker. (B) β-Galactosidase assay of BCBL-1 (bar 1), Flp-In BCBL1 (bar 2), TREx BCBL1 (bar 3), TREx BCBL1-Rta (bar 4), and TREx BCBL1-vector (bar 5). The values represent averages of three individual experiments, with the error bars showing standard deviations.