MAP2K2

MAP2K2 Background

Dual specificity mitogen-activated protein kinase kinase 2 is a protein in humans that is encoded by the MAP2K2 gene ^[1]. It is more commonly known as MEK2. The MAP2K/MEK2 protein bears substantial sequence homology to MEK1, except at its amino terminus, and a proline-rich region inserts between the conserved kinase subdomains 9 and 10 ^[2]. Northern analysis indicates that MEK2 is expressed at low levels in the adult mouse brain and heart tissue and at higher levels in other tissues examined ^[2]. However, MEK2 is expressed at high levels in the neonatal brain ^[2]. MAP2K/MEK2 plays a critical role in mitogen growth factor signal transduction. As a part of the RAS/MAPK pathway, MAP2K/MEK2 transmits chemical signals from outside the cell to the cell's nucleus. MAP2K/MEK2 is activated through Ser/Thr phosphorylation by MAP kinase kinase kinases. Activated MAP2K/MEK2 phosphorylates and activates MAPK1/ERK2 and MAPK3/ERK1, leading to their activation and further transduction of the signal within the MAPK/ERK cascade ^[3-7]. RAS/MAPK signaling helps control the proliferation of cells, the process by which cells mature to carry out differentiation, cell movement, and apoptosis. Bélanger LF et al. demonstrated that MEK2 is not necessary for the normal development of the embryo and T-cell lineages, suggesting that the loss of MEK2 can be compensated for by MEK1 ^[8].

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[2] Brott B. K., A. Alessandrini, et al. MEK2 is a kinase related to MEK1 and is differentially expressed in murine tissues [J]. Cell Growth Differ. 1993, 4:921-929.
[3] Crews, C. M., Alessandrini, A. et al. The primary structure of MEK, a protein kinase that phosphorylates the ERK gene product [J]. Science 1992, 258,478 -480.
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[7] Scholl FA, Dumesic PA, et al. Mek1/2 gene dosage determines tissue response to oncogenic Ras signaling in the skin [J]. Oncogene 2009; 28: 1485-95.
[8] Bélanger LF, Sophie Roy, et al. Mek2 is dispensable for mouse growth and development [J]. Molecular and Cellular Biology, 01 Jul 2003, 23(14):4778-4787.