Mitogen-activated protein kinases (MAPKs) are a group of serine/threonine protein kinases that play a crucial role in various cellular processes such as cell growth, differentiation, proliferation, and apoptosis. They are triggered and activated in response to extracellular signals, including growth factors, cytokines, hormones, and stress stimuli.
MAPKs are characterized by a highly conserved three-tiered signaling module consisting of a MAPK kinase kinase (MAPKKK), a MAPK kinase (MAPKK), and the MAPK itself. The activation of this module occurs through a phosphorylation cascade, where the MAPKKK phosphorylates and activates the MAPKK, which in turn phosphorylates and activates the MAPK.
Among the various MAPK subfamilies, the mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) pathway is the most well-known and extensively studied. It is primarily associated with cell survival, proliferation, and differentiation. MAPK/ERK pathway dysregulation has been implicated in various diseases, including cancer, neurological disorders, and cardiovascular diseases.
In summary, mitogen-activated protein kinases are a class of enzymes that transmit signals from the cell surface to the nucleus, regulating vital cellular processes. Their activation and subsequent phosphorylation cascade are triggered by extracellular signals and are essential for maintaining normal cellular function. Understanding the molecular mechanisms of MAPKs provides insights into disease pathogenesis and offers potential therapeutic targets for drug development.
