Multiple roles of MAP kinases in plant signal transduction

The MAP kinases are important mediators of intracellular signal transduction, and regulation involving them has been implicated in a wide variety of physiological processes. Studies in yeast and mammals have identified subgroups of these enzymes that have different substrate specificities and are regulated by different extracellular stimuli. Recently, studies in plants have revealed that there is a similar divergence of MAP kinase functions, and pathways involving MAP kinases have been linked to signal transduction caused by wounding, pathogens and abiotic stresses, as well as the plant hormones abscisic acid, auxin and ethylene. Thus, pathways involving MAP kinases are a common mechanism for signal transduction in all eukaryotes, and have been adapted to couple distinct stimuli to specific physiological responses.