Mitogen-activated protein kinase kinase kinase 9 (MAP3K9)

Serine/threonine kinase which functions as an essential component of the MAP kinase signal transduction pathway. Plays an essential role in the cascades of cellular responses evoked by changes in the environment.

Once activated, functions as an upstream activator of the MKK/JNK signal transduction cascade throughout the phosphorylation of MAP2K4/MKK4 and MAP2K7/MKK7 which in turn activate the JNKs. The MKK/JNK signaling pathway regulates stress response via activator protein-1 (JUN) and GATA4 transcription factors.