title: Evolution of osmosensing signal transduction in Metazoa: stress-activated protein kinases p38 and JNK.
abstract: Sponges (Porifera) represent the most basal branch of the Metazoa alive today. We show that two central stress-activated protein kinases involved in the osmosensing pathway, p38 mitogen-activated protein kinase (MAPK) and JNK, can complement for the ancestral MAPK Hog1 in the yeast Saccharomyces cerevisiae. S. cerevisiae mutants lacking Hog1 (hog1-Delta 1) have been complemented with the sponge SDJNK and SDp38 genes. Western blotting has revealed that, after transformation, the hog1-Delta 1+ SDJNK(sense) and hog1-Delta 1+ SDp38(sense) clones express the sponge proteins. Functional studies have demonstrated that the complemented clones grow under hyperosmotic conditions (0.6 M NaCl). Furthermore, the expressed sponge kinases undergo phosphorylation in S. cerevisiae at 0.6 M NaCl. This report documents that the metazoan signal transduction kinases, p38 and JNK, which were originally derived from an common ancestor with yeast HOG1, have retained their function after their specification.
authors.affiliation: Institut für Physiologische Chemie, Abteilung für Angewandte Molekularbiologie, Universität, Duesbergweg 6, 55099 Mainz, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Böhm
authors.forename: Vera
authors.initials: V
authors.lastname: Gamulin
authors.forename: Heinz C
authors.initials: HC
authors.lastname: Schröder
authors.forename: Werner E G
authors.initials: WE
authors.lastname: Müller
mesh_terms: D000818:Animals; D048031:JNK Mitogen-Activated Protein Kinases; D048670:MAP Kinase Kinase 4; D048055:Mitogen-Activated Protein Kinase 8; D020929:Mitogen-Activated Protein Kinase Kinases / Q000378:metabolism*; D020928:Mitogen-Activated Protein Kinases / Q000235:genetics / Q000378:metabolism*; D009997:Osmotic Pressure; D010766:Phosphorylation; D010802:Phylogeny; D011161:Porifera / Q000201:enzymology*; D012441:Saccharomyces cerevisiae / Q000201:enzymology; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics; D015398:Signal Transduction / Q000502:physiology*; D012965:Sodium Chloride / Q000494:pharmacology; D014170:Transformation, Genetic; D014882:Water-Electrolyte Balance / Q000502:physiology*; D048051:p38 Mitogen-Activated Protein Kinases
chemical_list: D029701:Saccharomyces cerevisiae Proteins; D012965:Sodium Chloride; C088589:HOG1 protein, S cerevisiae; D048031:JNK Mitogen-Activated Protein Kinases; D048055:Mitogen-Activated Protein Kinase 8; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; D048670:MAP Kinase Kinase 4; D020929:Mitogen-Activated Protein Kinase Kinases