Mitogen-activated protein kinase kinase

Mitogen-activated protein kinase kinase [sic] (also known as MAP2K) is a kinase enzyme which phosphorylates mitogen-activated protein kinase (MAPK).

MAP2K is classified as.

There are seven genes:
 * (aka MEK1)
 * (aka MEK2)
 * (aka MKK3)
 * (aka MKK4}
 * (aka MKK5)
 * (aka MKK6)
 * (aka MKK7)

The activators of p38 (MKK3 and MKK6), JNK (MKK4 and MKK7), and ERK (MEK1 and MEK2) define independent MAP kinase signal transduction pathways.