Recombinant human mitogen-activated protein kinase kinase 3 (MKK3), unactive, 10 µg

Background: MEK3 / MKK3 is a dual specificity kinase belonging to the group of MAP kinase kinase (MKKs). MKKs are one part of three-kinase phosphorelay system „MAPK cascade“ that converts extra cellular stimuli into various cellular responses such as gene expression, mitosis, and differentiation, proliferation, and cell survival/apoptosis. Upon phosphorylation by MKKKs (e.g. MLKs, ASK1, TAK1) activated MEK3 / MKK3 is able to phosphorylate the Thr - Gly -Tyr motif in the activation loop of p38α, p38β, p38γ and p38δ. MKK6, a closely related MKK serves also as activator of p38 MAPK. The activation of the  p38MAPKs by one or more MKK is stimulus-specific and cell specific. Whereas MKK3 seems to be the major activator of p38 in mesangial cells, MKK6 appears to be the predominant isoform in thymocytes. In contrast, both kinases are needed for full p38α activation in response to stimulation by TNFα. Upon UV irradiation, p38α is activated by MKK3, MKK6 and MKK4, which has also a minor contribution for p38α activity.

Protein is not phosphorylated and activated by MKKKs. Suitable as substrate for use in kinase activity assays, for kinase binding assays and for western blot analyses.

Theoretical MW: MEK3 / MKK3 (Fusion Protein): 40.7 kDa
Expression system: E.coli
Purification:  One-step affinity purification using immobilized metal affinity chromatography (IMAC) resin charged with cobalt.
Purity: >95% (The purified fusion protein was analyzed on Coomassie stained SDS gel.)
Protein concentration: 0.32 mg/ml
Storage buffer: 20 mM Tris-HCl, 150 mM NaCl, 1 mM DTT, 20 % glycerol, pH 8.0                                                                 
Ordering information: shipped on dry ice

Entrez Gene ID: 5606
UniProtKB: P46734

Product specific literature:

Remy G, Risco AM, Iñesta-Vaquera FA, González-Terán B, Sabio G, Davis RJ, Cuenda A. (2010) “Differential activation of p38MAPK isoforms by MKK6 and MKK3.” Cell Signal. 22(4):660-7.

Cuenda A, Rousseau S. (2007) „ p38 MAP-kinases pathway regulation, function and role in human diseases.“ Biochim Biophys Acta, 1773(8):1358-75.

N. Tanaka, M. Kamanaka, H. Enslen, C. Dong, M.Wysk, R.J. Davis, R.A.Flavell,(2002) “Differential involvement of p38 mitogen-activated protein kinase kinases MKK3 and MKK6 in T-cell apoptosis” EMBO Rep. 3 785–791.