MAP2K4

(redirected from c-Jun N-terminal kinase kinase 1)

MAP2K4

A gene on chromosome 17q11.2 that encodes a MAPK kinase belonging to a protein kinase signal transduction cascade. MAP2K4 is a dual-specificity kinase and an essential component of the MAP kinase signal transduction pathway. It is also an essential component of the stress-activated protein kinase/c-Jun N-terminal kinase (SAP/JNK) signalling pathway, which is involved in the mitochondrial death signalling pathway, including the release cytochrome c, leading to apoptosis. With MAP2K7/MKK7, it is the only known kinase to directly activate the SAP/JNKs MAPK8/JNK1, MAPK9/JNK2 and MAPK10/JNK3; whereas MAP2K7/MKK7 exclusively activates JNKs, MAP2K4/MKK4 also activates the p38 MAPKs MAPK11, MAPK12, MAPK13 and MAPK14. MAP2K4 is required for maintaining peripheral lymphoid homeostasis. It is widely expressed in tissues, especially in skeletal muscle.