The BioGRID | PUBLICATION VIEW

	Cell Mar (1994); 76(6):1025-37
JNK1: a protein kinase stimulated by UV light and Ha-Ras that binds and phosphorylates the c-Jun activation domain.
Derijard B, Hibi M, Wu IH, Barrett T, Su B, Deng T, Karin M, Davis RJ
Howard Hughes Medical Institute, Department of Biochemistry and Molecular Biology, University of Massachusetts Medical School, Worcester 01605.
Abstract: The ultraviolet (UV) response of mammalian cells is characterized by a rapid and selective increase in gene expression mediated by AP-1 and NF-kappa B. The effect on AP-1 transcriptional activity results, in part, from enhanced phosphorylation of the c-Jun NH2-terminal activation domain. Here, we describe the molecular cloning and characterization of JNK1, a distant relative of the MAP kinase group that is activated by dual phosphorylation at Thr and Tyr during the UV response. Significantly, Ha-Ras partially activates JNK1 and potentiates the activation caused by UV. JNK1 binds to the c-Jun transactivation domain and phosphorylates it on Ser-63 and Ser-73. Thus, JNK1 is a component of a novel signal transduction pathway that is activated by oncoproteins and UV irradiation. These properties indicate that JNK1 activation may play an important role in tumor promotion.
[PUBMED: 8137421]