MOLECULAR-CLONING AND CHARACTERIZATION OF THE GENE ENCODING HUMAN NEUROD

NeuroD is a basic helix-loop-helix transcription factor that binds to an E-box sequence, CANNTG, in the target gene promoter region. The gen e encoding NeuroD is expressed specifically in brain, intestine, and p ancreatic cells and plays a pivotal role in tissue-specific differenti ation. To investigate the regulation of human NeuroD gene expression, we isolated and sequenced a genomic DNA containing two exons and flank ing regions of the NeuroD gene. The sizes of exons 1 and 2 were 168 an d 2404 bp, respectively. CAT reporter analysis showed that the element s responsible for basal promoter activity lay in the proximal 408-bp r egion. Cotransfection of the CAT reporter plasmids with a NeuroD expre ssion plasmid resulted in 5-fold enhancement of the CAT activity, indi cating an autoregulatory mechanism is involved in human NeuroD gene ex pression. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved.