Zinc finger transcription factors or ZF-TFs, are transcription factors composed of a zinc finger-binding domain and any of a variety of transcription-factor effector-domains that exert their modulatory effect in the vicinity of any sequence to which the protein domain binds.
[1] Zinc finger protein transcription factors can be encoded by genes small enough to fit a number of such genes into a single vector, allowing the medical intervention and control of expression of multiple genes and the initiation of an elaborate cascade of events.
They also have the advantage that the targeted sequence need not be symmetrical unlike most other DNA-binding motifs based on natural transcription factors that bind as dimers.
[1] By targeting the ZF-TF toward a specific DNA sequence and attaching the necessary effector domain, it is possible to downregulate or upregulate the expression of the gene(s) in question while using the same DNA-binding domain.
[1][3] Besides the obvious development of tools for the research of gene function, engineered ZF-TFs have therapeutic potential including correction of abnormal gene expression profiles (e.g., erbB-2 overexpression in human adenocarcinomas)[4][5] and anti-retrovirals (e.g. HIV-1[6]).