Transcription Factors

The AP-1 transcription factor is a dimeric transcription factor composed of proteins from several families including Jun, Fos, ATF, and Maf. AP-1 regulates various cell-autonomous as well as general physiological and pathological effects. This review describes the proteins making up AP-1, briefly mentions the diverse mechanisms by which the expression and activity of its components are regulated, and categorizes the major types of genes regulated by it. The experimental evidence implicating AP-1 in different processes such as proliferation, differentiation, apoptosis, migration and wound healing, malignant transformation, and angiogenesis are summarized also. The roles of AP-1 in disorders of the respiratory system are specified. Appropriate examples are provided to demonstrate AP-1 activity in the above-mentioned processes. The complexity of AP-1 research is emphasized as different AP-1 combinations may elicit different biological effects according to cell type, developmental stage, availability of interacting cofactors, and environmental conditions.