p38 MAPK Phospho-p38 MAPK Activation of p38 MAPK Authored: Jupe, S, 2011-04-08 Edited: Jupe, S, 2011-04-28 Pubmed10066767 Pubmed15686620 Pubmed7693711 Pubmed8633070 Pubmed8663524 Pubmed9430721 Reactome Database ID Release 431247960 Reactome, http://www.reactome.org ReactomeREACT_75807 Reviewed: Kufer, TA, 2011-04-28 Reviewed: Rittinger, K, 2011-06-06 Reviewed: Wong, Edmond, 2011-06-06 has a Stoichiometric coefficient of 8 p38 MAPK has 4 representative isoforms in humans, p38 alpha (Han et al. 1993), p38-beta (Jiang et al. 1996), p38-gamma (Lechner et al. 1996) and p38-delta (Hu et al. 1999). All are activated by phosphorylation on a canonical TxY motif by the dual-specificity kinase MKK6, which displays minimal substrate selectivity amongst the p38 isoforms (Zarubin & Han, 2005). p38 alpha and gamma are also activated by MKK3.