Mitogen-Activated Protein Kinase Kinase

**Semantic type:** Amino Acid, Peptide, or Protein|Enzyme

**Definition:** A family of dual-specific protein kinases that are activated through phosphorylation by mitogen-activated protein kinase kinase kinase (MAP3K, MAPKKK) proteins and can subsequently phosphorylate and activate mitogen-activated protein kinases (MAPK).

**Synonyms:** - MAP Kinase Kinase - MAP2K - MAPKK - MAPKK1 - MEK - MEK1 - MEK2 - MKK