title: Molecular cloning and characterization of a Drosophila p38 mitogen-activated protein kinase.
abstract: A mitogen-activated protein kinase (MAPK) has been cloned and sequenced from a Drosophila neoplasmic l(2)mbn cell line. The cDNA sequence analysis showed that this Drosophila kinase is a homologue of mammalian p38 MAPK and the yeast HOG1 gene and thus was referred to as Dp38. A distinguishing feature of all MAPKs is the conserved sequence TGY in the activation domain. Dp38 was rapidly tyrosine 186-phosphorylated in response to osmotic stress, heat shock, serum starvation, and H2O2 in Drosophila l(2)mbn and Schneider cell lines. However, unlike mammalian p38 MAPK, the addition of lipopolysaccharide (LPS) did not significantly affect the phosphorylation of Dp38 in the LPS-responsive l(2)mbn cell line. Following osmotic stress, tyrosine 186-phosphorylated forms of Dp38 MAPK were detected exclusively in nuclear regions of Schneider cells. Yeast complementation studies demonstrated that the Saccharomyces cerevisiae HOG1 mutant strain JBY10 (hog1-Delta1) was functionally complemented by Dp38 cDNA in hyperosmolar medium. These findings demonstrate that similar osmotic stress-responsive signal transduction pathways are conserved in yeast, Drosophila, and mammalian cells, whereas LPS signal transduction pathways appear to be different.
authors.affiliation: Laboratory of Immunology, Medical Research Center, College of Medicine, Yonsei University, CPO Box 8044, Seoul, South Korea.
authors.forename: S J
authors.initials: SJ
authors.lastname: Han
authors.forename: K Y
authors.initials: KY
authors.lastname: Choi
authors.forename: P T
authors.initials: PT
authors.lastname: Brey
authors.forename: W J
authors.initials: WJ
authors.lastname: Lee
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000235:genetics* / Q000378:metabolism; D002460:Cell Line; D003001:Cloning, Molecular; D004330:Drosophila / Q000201:enzymology / Q000235:genetics*; D005816:Genetic Complementation Test; D020928:Mitogen-Activated Protein Kinases; D008969:Molecular Sequence Data; D010766:Phosphorylation; D017386:Sequence Homology, Amino Acid; D013347:Subcellular Fractions / Q000201:enzymology; D014443:Tyrosine / Q000378:metabolism; D048051:p38 Mitogen-Activated Protein Kinases
chemical_list: D014443:Tyrosine; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases