phospho MKK4/ phospho MKK7 MKK4/MKK7 Activated TAK1 phosphorylates MKK4/MKK7 Authored: Shamovsky, V, 2009-12-16 EC Number: 2.7.11 Edited: Shamovsky, V, 2010-02-27 In human, phosphorylation of MKK4 and MKK7 by TAK1 occurs at the typical Ser-Xaa-Ala-Xaa-Thr motif in their activation loops.<p>Residues involved in activation of these protein kinases correspond to human Ser271, Thr275 in MKK7 and Ser257, Thr261 in MKK4.<p>Cell lines lacking MKK4 exhibit defective activation of JNK and AP-1 dependent transcription activity in response to some cellular stresses; JNK and p38 MAPK activities were decreased by around 80% and 20%, respectively, following deletion of the mkk4 gene. Pubmed15837794 Pubmed16186825 Pubmed17875933 Pubmed8533096 Reactome Database ID Release 43450337 Reactome, http://www.reactome.org ReactomeREACT_21367 Reviewed: Gillespie, ME, 2010-02-27 has a Stoichiometric coefficient of 2