The protein encoded by this gene is a member of the MAP kinase family MAP kinases act as an integration point for multiple biochemical signals and are involved in a wide variety of cellular processes such as proliferation differentiation transcription regulation and development This kinase is activated by various cell stimuli and targets specific transcription factors and thus mediates immediate-early gene expression in response to cell stimuli The activation of this kinase by tumor-necrosis factor alpha (TNF-alpha) is found to be required for TNF-alpha induced apoptosis This kinase is also involved in UV radiation induced apoptosis which is thought to be related to cytochrom c-mediated cell death pathway Studies of the mouse counterpart of this gene suggested that this kinase play a key role in T cell proliferation apoptosis and differentiation Several alternatively spliced transcript variants encoding distinct isoforms have been reported [provided by RefSeq Apr 2016]