期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1991
卷号:88
期号:22
页码:10222-10226
DOI:10.1073/pnas.88.22.10222
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:We demonstrate that JunD, a component of the AP-1 transcription factor complex, activates transcription of the human proenkephalin gene in a fashion that is completely dependent upon the cAMP-dependent protein kinase, protein kinase A. Activation of proenkephalin transcription by JunD is dependent upon a previously characterized cAMP-, phorbol ester-, and Ca(2+)-inducible enhancer, and JunD is shown to bind the enhancer as a homodimer. Another component of the AP-1 transcription complex, JunB, is shown to inhibit activation mediated by JunD. As a homodimer JunB is unable to bind the enhancer; however in the presence of c-Fos, high-affinity binding is observed. Furthermore, JunD is shown to activate transcription of genes linked to both cAMP and phorbol ester response elements in a protein kinase A-dependent fashion, further blurring the distinction between these response elements. These results demonstrate that the transcriptional activity of an AP-1-related protein is regulated by the cAMP-dependent second-messenger pathway and suggest that JunD and other AP-1-related proteins may play an important role in the regulation of gene expression by cAMP-dependent intracellular signaling pathways.