MAP three kinase 1, MAP/ERK kinase kinase 4, MAP3K4, MAPK/ERK kinase kinase 4, MAPKKK4, MEK kinase 4, MEKK4, Mitogen-activated protein kinase kinase kinase 4, MTK1, predicted protein of HQ0412, PRO0412.
Component of a protein kinase signal transduction cascade. Activates the CSBP2, P38 and JNK MAPK pathways, but not the ERK pathway. Specifically phosphorylates and activates MAP2K4 and MAP2K6.