TPL2 phosphorylates MEK1, SEK1 Authored: Ray, KP, 2010-05-17 EC Number: 2.7.11.25 Edited: Jupe, S, 2010-05-17 Pubmed17709378 Pubmed8131746 Reactome Database ID Release 43451649 Reactome, http://www.reactome.org ReactomeREACT_22271 Reviewed: Pinteaux, E, 2010-05-17 Tpl2 (also known as Cot) is constitutively bound to NFKB p105 (p105) which inhibits its MEK kinase activity in resting cells. Proteolysis of p105 frees Tpl2 from p105 and allows subsequent phosphorylation and activation of MEK1. Tpl2 can also activate SEK1. Phosphorylation of Tpl-2 is believed to play a role in its activation (Cho et al, 2005; Robinson et al. 2007). <br>Positions of phosphorylations represented here are inferred from general experimental data (Zheng & Guan, 1994). has a Stoichiometric coefficient of 2 Phospho-MEK1, phospho-SEK1 MEK1, SEK1