Dual specificity kinase. Is activated by cytokines and environmental stress in vivo. Catalyzes the concomitant phosphorylation of a threonine and a tyrosine residue in the MAP kinase p38. Part of a signaling cascade that begins with the activation of the adrenergic receptor ADRA1B and leads to the activation of MAPK14. MAP2K3 Protein, Human, Recombinant (His & SUMO) is expressed in E. coli expression system with N-6xHis-SUMO tag. The predicted molecular weight is 55.3 kDa and the accession number is P46734.