The protein encoded by this gene is a serine/threonine-protein kinase, which is targeted by both the extracellular signal-regulated kinase and p38 mitogen-activated protein kinase pathways. This enzyme targets several substrates including eukaryotic translation initiation factor 4E and mammalian target of rapamycin, which are negatively regulated by its phosphorylation. Null mutant mice do not exhibit developmental or reproductive defects. However, mice null for both this protein and mitogen-activated protein kinase-interacting serine/threonine protein kinase 1 have delayed tumor development in phosphatase and tensin homolog mutant mice, indicating an oncogenic function for this gene in tumor development. [provided by RefSeq, Oct 2014]