a protein kinase of the MAPK family that is potently activated by a variety of environmental stress and pro-inflammatory cytokines. Brain-selective JNK isoform. A pro-apoptotic protein and potential tumor suppressor. Phosphorylates a number of transcription factors including c-Jun, ATF2 and ELK1. Required for stress-induced neuronal apoptosis and the pathogenesis of glutamate excitotoxicity. CDK5 can phosphorylate and inhibit the activity of this kinase, which may be important in preventing neuronal apoptosis. Binds to at least four scaffolding proteins, JIP-1, -2, -3 and -4. Interacts with HDAC9. Expression lost in brain tumors. May function in neuronal cell death from injury and neurodegeneration, for which inhibitors are being developed. Two alternatively spliced transcript variants have been reported. Note: This description may include information from UniProtKB.
Protein type: CMGC group; EC 126.96.36.199; JNK subfamily; Kinase, protein; MAPK family; MAPK/JNK subfamily; Protein kinase, CMGC; Protein kinase, Ser/Thr (non-receptor)
Molecular Function: JUN kinase activity; MAP kinase kinase activity; protein binding
Biological Process: JNK cascade; neuron development; protein amino acid phosphorylation; regulation of circadian rhythm; regulation of gene expression; regulation of transcription factor activity; response to light stimulus; signal transduction