MEKK4: Proteins and Enzymes

MEK kinase 4 (MEKK4), also known as MTK1, is a Ser/Thr protein kinase belonging to the MAP kinase kinase kinase family (1). This protein contains a protein kinase catalytic domain at the C-terminus. The N-terminal, non-kinase domain may contain a regulatory domain. MEKK4 regulates p38 and JNK, butnot ERK pathway, through the phosphorylation of the MAP2Ks MKK3 and MKK6 and MKK4 and MKK7 respectively (1-2).