The study of gene expression and gene regulation is critical in the development of novel gene therapies.
Transcriptional control is, thus, a major area of interest.
Initiation of transcription requires binding of an RNA polymerase to a promoter, but this process is highly controlled. Transcription can be regulated in either a positive or negative fashion by transcription factors which bind at or near the transcription start site. For example, general transcription factors are required for the initiation of all promoters and act by recruiting RNA polymerase to the start site. In contrast, inducible factors recognize short consensus sequences upstream of the start site but are activated at specific times or in specific tissues to modulate the efficiency of initiation and control transcription patterns in space and time. OxyR is an inducible transcription factor which activates the expression of antioxidant genes including hydrogen peroxidase I, glutathione reductase, and glutaredoxin.