Transcription activator involved in oxidative stress response and redox homeostasis. Regulates the transcription of genes encoding antioxidant enzymes and components of the cellular thiol-reducing pathways, including the thioredoxin system (TRX2, TRR1), the glutaredoxin system (GSH1, GLR1), superoxide dismutase (SOD1, SOD2), glutathione peroxidase (GPX2), and thiol-specific peroxidases (TSA1, AHP1). The induction of some of these genes requires the cooperative action of both, YAP1 and SKN7. Preferentially binds to promoters with the core binding site 5'-TTA[CG]TAA-3'. Activity of the transcription factor is controlled through oxidation of specific cysteine residues resulting in the alteration of its subcellular location. Oxidative stress (as well as carbon stress, but not increased temperature, acidic pH, or ionic stress) induces nuclear accumulation and as a result YAP1 transcriptional activity. Activation by hydrogen peroxide or thiol-reactive chemicals elicit distinct adaptive gene responses. Nuclear export is restored when disulfide bonds are reduced by thioredoxin (TRX2), whose expression is controlled by YAP1, providing a mechanism for negative autoregulation. When overexpressed, YAP1 confers pleiotropic drug-resistance and increases cellular tolerance to cadmium, iron chelators and zinc.
