MAP2K5 (Mitogen-Activated Protein Kinase Kinase 5): MAP2K5 is a kinase enzyme that functions within the mitogen-activated protein kinase (MAPK) signaling pathway. It plays a role in cellular responses to growth factors, stress, and cytokines. MAP2K5 is involved in processes such as cell growth, differentiation, and apoptosis. Dysregulation of MAP2K5 may contribute to the development of cancer and other diseases.