Analysis of cis-acting promoter elements using microinjected synthetic oligonucleotides

The transferrin receptor (TR) is expressed in a proliferation-dependent manner that requires transcriptional activation of its gene. Furthermore TR function is required for the DNA synthetic phase of the cell cycle. Oligonucleotides encoding promoter elements within the human transferrin receptor gene were injected into quiescent fibroblasts. The cells were then serum stimulated and the effect of the oligonucleotides on nuclear labeling with [ 3H]thymidine was determined. Inhibition was observed for oligonucleotides corresponding to a specific region of the promoter.