Endocrine Abstracts (2007) 13 P163

An engineered zinc finger transcription factor that activates the endogenous human insulin gene in non β cells

Laura Ferguson, Hilary Docherty & Kevin Docherty


University of Aberdeen, Aberdeen, United Kingdom.


The insulin gene is expressed almost exclusively in the β cells of the islets of Langerhans, where transcriptional control is conferred by cis-acting regulatory sequences located within 300–400 base pairs from the transcription start site. These elements bind β-cell restricted (e.g. PDX-1) and ubiquitous (E47) transcription factors. In non-β cells the insulin gene is localised within tightly packed (hetero) chromatin structures. Developments in understanding the role of chromatin and protein-DNA interactions in the control of gene expression have led to a technology based on designer transcription factors that regulate specific genes in vivo. These proteins contain two modules: a zinc finger based DNA binding domain and a functional domain which can either activate or repress genes. Such engineered zinc finger transcription factors (ZFP-TFs) have been used to regulate a variety of clinically relevant genes in human cells, including erythropoietin and VEGF. Here we describe an engineered zinc finger transcription factor (ZFP) that was isolated from a library of ZFPs on the basis of its ability to strongly activate the endogenous insulin gene in HEK-293 cells. Under similar conditions a PDX-VP64 construct that has been shown by others to activate the endogenous insulin gene in liver had no effect. The INS-ZFP contains a 3-finger DNA-binding domain, the nuclear translocation signal from SV40 large T antigen, the transactivation domain of the VP16 protein from Herpes simplex, and a Flag tag. The INS-ZFP acts directly on the insulin promoter through sequences located within the proximal promoter region. These sequences are absent from the rat insulin promoter.

Article tools

My recent searches

No recent searches.