title: Geranylgeranyltransferase Cwg2-Rho4/Rho5 module is implicated in the Pmk1 MAP kinase-mediated cell wall integrity pathway in fission yeast.
abstract: Pmk1, a fission yeast homologue of mammalian ERK MAPK, regulates cell wall integrity, cytokinesis, RNA granule formation and ion homeostasis. Our screen for vic (viable in the presence of immunosuppressant and chloride ion) mutants identified regulators of the Pmk1 MAPK signaling, including Cpp1 and Rho2, based on the genetic interaction between calcineurin and Pmk1 MAPK. Here, we identified the vic2-1 mutants carrying a mis-sense mutation in the cwg2(+) gene encoding a beta subunit of geranylgeranyltransferase I (GGTase I), which participates in the post-translational C-terminal modification of several small GTPases, allowing their targeting to the membrane. Analysis of the vic2-1/cwg2-v2 mutant strain showed that the localization of Rho1, Rho4, Rho5 and Cdc42, both at the plasma and vacuolar membranes, was impaired in the vic2-1/cwg2-v2 mutant cells. In addition, Rho4 and Rho5 deletion cells exhibited the vic phenotype and cell wall integrity defects, shared phenotypes among the components of the Pmk1 MAPK pathway. Consistently, the phosphorylation of Pmk1 MAPK on heat shock was decreased in the cwg2-v2 mutants, and rho4- and rho5-null cells. Moreover, Rho4 and Rho5 associate with Pck1/Pck2. Possible roles of Cwg2, Rho4 and Rho5 in the Pmk1 signaling will be discussed.
authors: Laboratory of Molecular Pharmacogenomics, School of Pharmaceutical Sciences, Kinki University, Kowakae 3-4-1, Higashi-Osaka, 577-8502, Japan; Japan Society for the Promotion of Science, 1-8 Chiyoda-ku, Tokyo, 102-8472, Japan.
authors: Akira
authors: A
authors: Doi
authors: Ayako
authors: A
authors: Kita
authors: Yuki
authors: Y
authors: Kanda
authors: Takaya
authors: T
authors: Uno
authors: Keita
authors: K
authors: Asami
authors: Ryosuke
authors: R
authors: Satoh
authors: Kentaro
authors: K
authors: Nakano
authors: Reiko
authors: R
authors: Sugiura
mesh_terms: D019883:Alkyl and Aryl Transferases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D002473:Cell Wall / Q000378:metabolism*; D019204:GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D020935:MAP Kinase Signaling System; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D009154:Mutation; D010766:Phosphorylation; D017434:Protein Structure, Tertiary; D012568:Schizosaccharomyces / Q000166:cytology / Q000235:genetics / Q000378:metabolism*; D029702:Schizosaccharomyces pombe Proteins / Q000235:genetics / Q000378:metabolism*; D020741:rho GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: C506338:RHO4 protein, S pombe; D029702:Schizosaccharomyces pombe Proteins; D019883:Alkyl and Aryl Transferases; C000601235:Cwg2 protein, S pombe; C083291:geranylgeranyltransferase type-I; D020928:Mitogen-Activated Protein Kinases; C516338:Pmk1 protein, S pombe; D019204:GTP-Binding Proteins; C504664:RHO5 protein, S pombe; D020741:rho GTP-Binding Proteins