The Mitogen-activated Protein Kinase (MAPK) Cascades

1. The Mitogen-activated Protein Kinase (MAPK) Cascades SIGMA-ALDRICH

2. The Mitogen-activated Protein Kinase (MAPK) Cascades Several MAPK cascades have been identified in mammalian cells, including the extracellular signal-related kinase pathways (ERK1/2, ERK5) and the stress activated kinase pathways (JNK/SAPK, p38 MAPK). These pathways are linked to many G protein-linked cell surface receptors and receptor tyrosine kinases. Thus, most cytokines, growth factors, hormones, and neurotransmitters can selectively activate these cascades via receptor activation of intracellular second messengers. All MAPK pathways operate through sequential phosphorylation events to phosphorylate transcription factors and regulate gene expression. They can also phosphorylate cytosolic targets to regulate intracellular events. These cascades are implicated in the regulation of cellular proliferation, differentiation, development, cell cycle, and transmission of oncogenic signals. Courtesy of Rony Seger, Ph.D., Dept. Membrane Research and Biophysics, Weizmann Institute of Science, Rehovot, Israel. References: Lowes, V.L., et al., Integration of signals from receptor tyrosine kinases and G protein-coupled receptors. Neurosignals, 11, 5-19 (2002). Tamura, S., et al., Regulation of stress-activated protein kinase signaling pathways by protein phosphatases. Eur. J. Biochem., 269, 1060-1066 (2002). Seger, R., and Krebs, E.G., The MAPK signaling cascade. FASEB J., 9, 726-735 (1995).