| Purification and Quality Control | The His-tag recombinant protein is purified by affinity chromatography in combination with FPLC columns. The purified MEK1- MAP Kinase Kinase (MAPKK) is greater than 95% homogeneous based on SDS-PAGE analysis. |
| Unit Definition (Activity) | 1 unit equals 1 nanogram of purified protein. |
| Applications | Recombinant MEK1 can be used for in vitro phosphorylation or dephosphorylation assays. |
| Formulation and Storage | The protein is in 20mM Tris-HCl pH7.9,100mM NaCl, 0.2mM EDTA, 1mM DTT and 20% glycerol. Stored at -70°C before use. Avoid repeated freeze thaw cycles. |
| Synonym | Homo sapiens mitogen-activated protein kinase kinase 1 (MAP2K1); MAPKK1; MEK1; MKK1 and PRKMK1. |
| Protein Sequence | MPKKKPTPIQ LNPAPDGSAV NGTSSAETNL EALQKKLEEL ELDEQQRKRL EAFLTQKQKV
GELKDDDFEK ISELGAGNGG VVFKVSHKPS GLVMARKLIH LEIKPAIRNQ IIRELQVLHE
CNSPYIVGFY GAFYSDGEIS ICMEHMDGGS LDQVLKKAGR IPEQILGKVS IAVIKGLTYL
REKHKIMHRD VKPSNILVNS RGEIKLCDFG VSGQLIDSMA NSFVGTRSYM SPERLQGTHY
SVQSDIWSMG LSLVEMAVGR YPIPPPDAKE LELMFGCQVE GDAAETPPRP RTPGRPLSSY
GMDSRPPMAI FELLDYIVNE PPPKLPSGVF SLEFQDFVNK CLIKNPAERA DLKQLMVHAF
IKRSDAEEVD FAGWLCSTIG LNQPSTPTHA AGV |
| Background | The mitogen-activated protein (MAP) kinase pathway has been implicated in the actions of many cellular processes including hormones, growth factors and oncogene products (1,2). The mitogen-activated protein kinase kinase 1 (MEK1 or MAPKK1) is one of the three isoforms of the protein serine/threonine kinase family. The mechanism of MEK1 activation involves protein phosphorylation specifically on serine 218 and 222 by MEK kinase (MEKK) or by autophosphorylation (3,4). Activation of MEK1 in vivo was also demonstrated through the inhibition of serine/threonine phosphayases by SV40 smal T antigen, an inhibitor of phosphatase PP2A (5). Oncogene products including Raf, Tpl-2 and Ras have been demonstrated to be involved in mediating MEK1 activity (6). |
| References | 1. Davis, RJ. (1993) J. Biol. Chem. 268, 14553-14556
2. Robbins, DJ. et al., (1994) Adv. Cancer Res. 63, 93-116
3. Xu, S. et al., (1995) Proc. Natl. Acad. Sci. USA 92, 6808-6812
4. Ahn, NG. et al., (1993) Proc. Natl. Acad. Sci. USA 90, 5143-5147
5. Sontag, E. et al., (1993) Cell 75, 887-897
6. Rajalingam, K. et al., (2005) Nat. Cell Biol. 7, 837-843 |
