Overview:

Mitogen-acitvated protein kinase kinase 3 (MEK3) is a serine/threonine kinase that is involved in the activation of MAP kinases. MEK3 is a dual-specificity protein kinase that phosphorylates p38 MAP kinase at its activation site Thr-Gly-Tyr and this stimulates the ability of p38 MAPK to phosphorylate protein substrates such as ATF-2 and Elk-1. MEK3 is activated by different forms of cellular stress and inflammatory cytokines. MEK3-null mice are viable and fertile, but their macrophages and dendritic cells are defective in IL-12 production (1). A virulence factor from Yersinia pseudotuberculosis, YopJ, was found to bind directly to MEK3 in vitro and this leads to blockage of its phosphorylation and activation (2).

Gene Aliases:

MAP2K3, MEK3, MAPKK3, PRKMK3, SKK2

Genbank Number:

NM_002756

References:

1. Lu, H.-T. et al: Defective IL-12 production in mitogen-activated protein (MAP) kinase kinase 3 (MEK3)-deficient mice. EMBO J. 18: 1845-1857, 1999.

2. Orth, K. et al: Inhibition of the mitogen-activated protein kinase kinase superfamily by a Yersinia effector. Science 285: 1920-1923, 1999.