Regulation of insulin gene transcription.

Selective transcription of the insulin gene in pancreatic beta cells is regulated by its enhancer, located between nucleotides -340 to -91 relative to the transcription start site. The activity o f the enhancer is controlled by both positive- and negative-acting cellular factors. Cell-type-specific expression is mediated principally by a single cis-acting enhancer element, termed the insulin control element (ICE), which is acted upon by both these cellular activities. This review focuses on the role of the factors acting on the ICE and other enhancer control elements in the establishment of cell-type-specific and physiologically regulated transcription of the insulin gene.