To test whether Dlx2 can regulate these candidate Zfhx1b enhancers we used a luciferase reporter assay. Co-transfection of a luciferase reporter construct containing enhancers #649 and #675 with a Dlx2 expression vector in P19 cells showed that DLX2 strongly activates luciferase transcription when these elements are present (Figure 5J).
