Role of the transcription factor AP-1 in melanoma differentiation

Although the molecular details remain to be elucidated, temporal changes in gene expression that result in discrete biochemical alterations and growth arrest are primary determinants of terminal cell differentiation. The control of gene expression is inextricably associated with proteins that can initiate or inhibit gene transcription. Specific genes contain within their promoter regions, DNA sequences that permit the binding of transactivating and transinhibiting proteins that can initiate or suppress transcription, respectively. Activating protein-1 (AP-1), a dimeric complex consisting of proteins encoded by the Jun and Fos gene families, is a transcription factor induced by a variety of signals, including those eliciting proliferation, differentiation and programmed cell death (apoptosis). We presently review the potential role of AP-1 proteins in differentiation with specific emphasis on melanoma differentiation.