Kinase Family MAPK

Kinase Classification: Group CMGC: Family MAPK

The MAPKs (Mitogen Activated Protein Kinase) are the final kinases of the MAPK cascade, which relay signals from the cell surface for growth, stress and other responses. The best-known MAPKs include Erk, which relays growth signals from the ras/raf pathway and receptor kinases, and the JNK and p38 subfamilies, which relay various stress signals.

Most MAPKs have a specific TxY motif in their activation loop, in which both the T and Y are phosphorylated by MEK (MAP2K) kinases in order to activate them. Erk3 (~SeG) and nmo (TxE) are variants that lack the Y.

The MAPK family has the following subfamilies:

Subfamily ERK1

The major MAPK subfamily that transduces cell growth signals. .

Subfamily ERK3

Poorly studied animal-specific family downstream of PAK kinases and possibly involved in cell cycle

Subfamily ERK5

The MEKK2-MEK5-ERK5 pathway is found in holozoa and transduces mechanical stress and other signals

Subfamily JNK

JNK and p38 are the major stress-activated MAPK pathways.

Subfamily p38

JNK and p38 are the major stress-activated MAPK pathways.

Subfamily nmo

Nemo kinases, activated in response to inflammatory and developmental signals by TAK1 (MLK family) rather than typical MAP2K kinases.

Subfamily ERK7

Found in almost all eukaryotes and likely autophosphorylates rather than being activated by a MAPK cascade. Wide variety of functions.