Figure 1.
Mitogen-activated protein kinase (MAPK) signaling pathways. MAPKs are activated by a variety of stimuli, including 12-O-tetradecanoyl-phorbol-13-acetate (TPA), growth factors, UV and
DNA damage. The final signal commonly includes transcription of target genes leading to cellular responses such as proliferation
or apoptosis. TAK, Tumor growth factor β–activating kinase.