Mitogen Activated Protein Kinase Kinase 1 (MAP3K1), also known as MAPKKK1, MEKK, or MEKK1, belongs to the MAP kinase kinase subfamily of the STE serine/threonine protein kinase family in the protein kinase superfamily. It is a key upstream regulatory molecule in the protein kinase signaling cascade. MAP3K1 is a bifunctional protein that contains a plant homologous domain (PHD) at its N-terminus, endowing it with E3 ubiquitin ligase activity; The C-terminus contains a kinase domain, giving it protein kinase activity. As an upstream kinase of the MAPK signaling pathway, MAP3K1 can activate multiple key signaling pathways by phosphorylating downstream molecules.
