Mitogen Activated Protein Kinases (MAPKs) are a family of intracellular enzymes that play a crucial role in various cellular processes such as cell growth, division, differentiation, and response to external stimuli. They are serine/threonine protein kinases that are activated by a variety of mitogens (substances that stimulate cell division) such as hormones, growth factors, and cytokines.
MAPKs are part of a signaling cascade that starts when a mitogen binds to its receptor on the cell surface. This triggers a series of phosphorylation events, leading to the activation of MAPKs. Once activated, MAPKs phosphorylate a wide range of substrates, including transcription factors, cytoskeletal proteins, and other kinases, thereby modulating gene expression and altering cellular functions.
There are several subfamilies of MAPKs, including extracellular signal-regulated kinases (ERKs), c-Jun N-terminal kinases (JNKs), and p38 MAPKs. Each subfamily has different downstream targets and is involved in specific cellular processes. For example, ERKs are primarily associated with cell proliferation and differentiation, while JNKs and p38 MAPKs are involved in stress responses, apoptosis, and immune responses.
Dysregulation of MAPK pathways has been implicated in the development of numerous diseases, including cancer, inflammation, neurodegenerative disorders, and cardiovascular diseases. Therefore, MAPKs have become an important target for therapeutic interventions, and the development of MAPK inhibitors has shown promise in clinical trials for the treatment of these diseases.
