Figure 4

GFP expression in progeny of double transgenic mice. Double transgenic mice were mated with wild-type mice to test transmission of Sleeping Beauty (SB) transposon insertions to progeny. If transmission of SB transposon insertions occur in progeny, then it would enable us to detect insertion with methods other than green fluorescent protein (GFP) expression, such as Southern blot analysis or fluorescence in situ hybridization analysis. Some of the progeny from the double transgenic mice are clearly GFP positive, and the intensity of GFP varied, suggesting that SB transposase mediated transpositions occurred and transposons integrated at various locations. wt, wild-type.