title: Ras-dependent activation of c-Jun N-terminal kinase/stress-activated protein kinase in response to interleukin-3 stimulation in hematopoietic BaF3 cells.
abstract: Activation of the c-Jun N-terminal kinase (JNK)/stress-activated protein kinase pathway in response to stimulation of the interleukin (IL)-3 or granulocyte-macrophage colony-stimulating factor (GM-CSF) receptor was examined in mouse hematopoietic BaF3-derived cell lines (BaF3-N6 and -V2 cells). Significant increase in the activity of JNK1 was observed within 30 min following IL-3 or GM-CSF stimulation at physiological concentrations. Dominant-negative Ras(S17N), which is conditionally expressed in the presence of isopropyl-1-thio-beta-D-galactoside in BaF3-N6 cells, prevented the IL-3 stimulation of JNK1, whereas anisomycin-induced JNK1 activation was unaffected. Furthermore, a deletion mutant of the common beta subunit for IL-3 and GM-CSF receptors that consists of only the membrane-proximal region, including box 1 and box 2 motifs, was incapable of facilitating JNK1 activity as well as Ras activation. These results provide evidence that Ras is required for IL-3-stimulated JNK1 activation. We also examined if constitutively active Ras(G12V) alone could stimulate JNK1 activity by using the inducible expression system. Isopropyl-1-thio-beta-D-galactoside induction of Ras(G12V) in the BaF3-V2 cell line caused no significant increase in JNK1 activity, which could be activated by IL-3 or anisomycin. On the contrary, the extracellular signal-regulated kinase/mitogen-activated protein kinase pathway was fully activated following Ras(G12V) induction. Together with these results, it seems likely that the Ras protein is indispensable for the IL-3 stimulation of JNK1 although Ras activation by itself is insufficient for JNK1 activation.
authors.affiliation: Faculty of Bioscience and Biotechnology, Tokyo Institute of Technology, Yokohama 226, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Terada
authors.forename: Y
authors.initials: Y
authors.lastname: Kaziro
authors.forename: T
authors.initials: T
authors.lastname: Satoh
mesh_terms: D000818:Animals; D001853:Bone Marrow / Q000187:drug effects* / Q000201:enzymology; D001854:Bone Marrow Cells; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000378:metabolism*; D002460:Cell Line; D004789:Enzyme Activation; D007377:Interleukin-3 / Q000494:pharmacology*; D048031:JNK Mitogen-Activated Protein Kinases; D051379:Mice; D020928:Mitogen-Activated Protein Kinases; D018631:ras Proteins / Q000378:metabolism*
chemical_list: D007377:Interleukin-3; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D048031:JNK Mitogen-Activated Protein Kinases; D020928:Mitogen-Activated Protein Kinases; D018631:ras Proteins