JNK3/MAPK10

JNK3 (MAPK10) is the tissue-restricted JNK isoform, expressed predominantly in neurons with additional expression in heart and testis, whereas JNK1 and JNK2 are ubiquitous. It is activated by MKK4 and MKK7 through phosphorylation of its Thr-Pro-Tyr motif and phosphorylates c-Jun, ATF2, and related AP-1 components. Genetic deletion in mice confers resistance to excitotoxic neuronal death induced by kainate and reduces apoptosis after cerebral ischemia, establishing JNK3 as a mediator of stress-induced neurodegeneration. Consequently it is pursued as a neuroprotection target in stroke, Alzheimer disease, and Parkinson disease models. Alternative splicing yields α and β isoforms. Recombinant JNK3 serves these studies and inhibitor screening.