p38 MAPK

The p38 MAPK family consists of highly conserved proline-directed serine-threonine protein kinases that are activated in response to a number many growth factors, cytokines, and chemotactic substances, such as vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF), PDGF, TNF, interleukins, lipopolysaccharide (LPS) and formyl-methionyl-leucyl-phenylalanine (fMLP). It is well known that p38 is involved in inflammation, apoptosis, cardiomyocyte hypertrophy and cell differentiation.

The p38 MAPK family is composed of four proteins: p38α (encoded by the gene Mapk14), p38β (Mapk11), p38γ (Mapk12), and p38δ (Mapk13). Their coding genes have a distinct tissue distribution and they appear differentially expressed, being Mapk14 the most highly expressed. p38 MAPKs are substrates for three MAP2K (MKK6, MKK3, and MKK4). The contribution of each of these MAP2K to p38 MAPKs activation depends on the stimulus and the cell type. The MAP3Ks that lead to p38 MAPKs activation are ASK1, DLK1, TAK1, TAO1, TAO2, TPL2, MLK3, MEKK3, MEKK4, and ZAK1.