Identification of c-Jun NH2-terminal protein kinase (JNK)-activating kinase 2 as an activator of JNK but not p38.
c-Jun NH2-terminal protein kinase (JNK), a distant member of the mitogen-activated protein (MAP) kinase family, regulates gene expression in response to various extracellular stimuli. JNK is activated by JNK-activating kinase 1 (JNKK1), a dual specificity protein kinase that phosphorylates JNK on threonine 183 and tyrosine 185 residues. Here we show that JNKK2, a novel member of the MAP kinase kinase family, was phosphorylated and activated by MEKK1, a MAP kinase kinase kinase in the JNK signaling cascade. JNKK2 activity was also stimulated by constitutively active forms of Rac and Cdc42Hs, members of the Rho small GTP-binding protein family. Unlike JNKK1 that activates both JNK and p38 MAP kinases, JNKK2 stimulated only JNK. Transient transfection assays demonstrated that JNKK2 potentiated the stimulation of c-Jun transcriptional activity by MEKK1. The existence of multiple JNK-activating kinases may contribute to the specificity of the JNK signaling cascade.[1]References
- Identification of c-Jun NH2-terminal protein kinase (JNK)-activating kinase 2 as an activator of JNK but not p38. Lu, X., Nemoto, S., Lin, A. J. Biol. Chem. (1997) [Pubmed]
Annotations and hyperlinks in this abstract are from individual authors of WikiGenes or automatically generated by the WikiGenes Data Mining Engine. The abstract is from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.About WikiGenesOpen Access LicencePrivacy PolicyTerms of Useapsburg
