catalytic activity:ATP + a protein = ADP + a phosphoprotein.,cofactor:Magnesium.,enzyme regulation:Homodimerization via the leucine zipper domains is required for autophosphorylation and subsequent activation.,function:Activates the JUN N-terminal pathway.,PTM:Autophosphorylation on serine and threonine residues within the activation loop plays a role in enzyme activation.,similarity:Belongs to the protein kinase superfamily. STE Ser/Thr protein kinase family. MAP kinase kinase kinase subfamily.,similarity:Contains 1 protein kinase domain.,similarity:Contains 1 SH3 domain.,subunit:Homodimer.,catalytic activity:ATP + a protein = ADP + a phosphoprotein.,cofactor:Magnesium.,enzyme regulation:Homodimerization via the leucine zipper domains is required for autophosphorylation and subsequent activation.,function:Activates the JUN N-terminal pathway.,PTM:Autophosphorylation on serine and threonine residues within the activation loop plays a role in enzyme activation.,similarity:Belongs to the protein kinase superfamily. STE Ser/Thr protein kinase family. MAP kinase kinase kinase subfamily.,similarity:Contains 1 protein kinase domain.,similarity:Contains 1 SH3 domain.,subunit:Homodimer.,
