Analysis of neuropeptide gene expression by transfection of DNA into cell lines

Abstract

The transcriptional regulation of neuropeptide genes by cAMP is often directed by a cAMP responsive enhancer (CRE) upstream to the promoter of the genes. The identity of the CRE was determined by transient transfection experiments and has the consensus sequence of 5′-TGACGTCA-3′. A large family of transcription factors have been identified which recognize the CRE. Transient transfection assays that employed expression of these factors driven by viral promoters have determined they can transactivate the neuropeptide gene promoters. Because of the large number of factors that have been identified as being able to recognize the CRE, it has been difficult to determine which factors mediate in vivo the transactivation of a particular CRE. Using a dominant negative mutant of one of these factors, CREB, it has been determined that both CREB as well as other factors which do not interact with CREB may mediate the cAMP response of the somatostatin gene.