A transgenic mouse that targets the expression of Cre recombinase in pancreatic tissue

The transgenic mice that express Cre recombinase in a tissue specific manner is a powerful tool in generating the conditional gene knockout mice. The rat insulin promoter was cloned target the expression of Cre in pancreatic tissue. The Cre gene was modified by adding the nuclear localization signal and the sequence for initiation by eukaryotic ribosomes at 5' terminal of the Cre gene. Cre gene was linked to the intron of human growth factor gene. This construct was introduced into the mouse eggs using microinjection. Seven mice were identified as founders carrying the Cre gene by PCR. The results of RT-PCR showed that the transgenic mouse from one founder could transcribe the foreign gene in pancreas. The Southern blot analysis indicated that the Cre recombinase expressed in pancreas of the transgenic mouse was functional.