EBV-Derived Episomes to Probe Chromatin Structure and Gene Expression in Human Cells

Gene therapy necessitates the controlled expression of the transferred gene. The expression of the most genes is regulated at the level of transcription initiation. Research in the past two decades has provided a wealth of information about the mechanisms of transcriptional control in human cells. The analysis of the promoter and enhancer DNA elements, and of the corresponding DNA-binding proteins, has provided an understanding of the basic mechanisms of transcription initiation (1 ). This information is now used to devise gene expression cassettes for gene therapy.