Dual specificity mitogen-activated protein kinase kinase 1 and Dual specificity mitogen-activated protein kinase kinase 2 (MAP2K1 (for kinase 1), MAP2K2 (for kinase 2); commonly also MEK1 and MEK2)

Dual specificity mitogen-activated protein kinase kinase 1 (MAP2K1/MEK1) and kinase 2 (MAP2K2/MEK2) are closely related cytoplasmic kinases belonging to the MAP kinase kinase (MAPKK/MEK) family[1][2][5]. They play a central role in the MAPK/ERK signaling cascade, phosphorylating and activating ERK1 (MAPK3) and ERK2 (MAPK1) in response to upstream RAF activation. This pathway controls critical cellular processes such as proliferation, differentiation, survival, apoptosis, and cytoskeletal rearrangement[2][3][5][7][8]. MAP2K1/2 genes are essential during development and dysregulation (by mutation or overactivation) is implicated in various cancers and developmental syndromes[3][7]. MEK1/2 are major drug targets; MEK inhibitors are FDA-approved for certain cancers, though effectiveness can be limited by specific resistance mutations in MAP2K1[7].

Other names

MEK1MKK1MAPKK1PRKMK1MEK2MKK2MAPKK2PRKMK2CFC4MEKMAP kinase kinase

Inhibition of kinase activity, preventing phosphorylation and activation of downstream ERK1/2 (MAPK3/1), blocking cell proliferation and survival pathways. Induction of apoptosis in susceptible cells (notably cancer cells with MAPK pathway activation). Overcoming resistance mutations via tailored inhibitors (class-dependent activity, see Class 1/2/3 mutation distinction).