Mitogen-activated protein kinase

![Example for the inner workings of a MAP3 kinase: the activation cycle of mammalian Raf proteins (greatly simplified overview).[6][7]](/uploads/202501/26/Raf-activation-cycle-sketch4146.png)


Mitogen-activated protein kinases (MAPK) are protein kinases that are specific to the amino acids serine, threonine, and tyrosine. MAPKs belong to the CMGC (CDK/MAPK/GSK3/CLK) kinase group.
MAPKs are involved in directing cellular responses to a diverse array of stimuli, such as mitogens, osmotic stress, heat shock and proinflammatory cytokines. They regulate cell functions including proliferation, gene expression, differentiation, mitosis, cell survival, and apoptosis.