Immunogen sequence: PAVSSMQGKR KALKLNFANP PFKSTARFTL NPNPTGVQNP HIERLRTHSI ESSGKLKISP EQHWDFTAED LKDLGEI. MAP2K4 (MEK4) serine/threonine kinase (mitogen-activated protein kinase 4) MEK4 or MKK4 is a dual specificity kinase of the STE7 family that phospho