Figure 4.

Efficient recombination induced by recombinant nlsCre protein. (A) RFP-expressing reporter cells were incubated for 6 h in medium containing 1.0, 1.5, 2.5 or 5 µM purified nlsCre protein. The proportion of eGFP-expressing cells (in which recombination has occurred) was determined 48 h later by FACS analysis. The plotted values are representative of two independent experiments. Fluorescence microscopy (B) and dot blot analysis of RFP/eGFP-expressing cells detected by FACS (C) of reporter cells treated with 2.5 µM nlsCre protein. Bar, 40 µm.