title: Inportance of phosphatidylinositol 3-phosphate in sporulation of Schizosaccharomyces pombe.
abstract: In Schizosaccharomyces pombe, Pik3p phosphorylates phosphatidylinositol (PI) to produce PI 3-P, which is further phosphorylated by Ste12p to yield PI 3,5-P2. Pik3p is required for both conjugation and sporulation. To test which of PI 3-P and PI 3,5-P2 is required for sporulation, diploid cells defective in production of PI 3,5-P2 were used. They underwent sporulation almost normally provided that the osmotic pressure of the medium was controlled, suggesting that not PI 3,5-P2 but PI 3-P was important. Electron microscopic analysis confirmed normal sporulation in the absence of PI 3,5-P2 although the forespore membrane was found to be less dense in these cells.
authors.affiliation: Laboratory of Biological Chemistry, Graduate School of Agricultural and Life Science, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Onishi
authors.forename: Yoko
authors.initials: Y
authors.lastname: Nakamura
authors.forename: Takako
authors.initials: T
authors.lastname: Koga
authors.forename: Aiko
authors.initials: A
authors.lastname: Hirata
authors.forename: Yasuhisa
authors.initials: Y
authors.lastname: Fukui
mesh_terms: D003470:Culture Media; D008854:Microscopy, Electron; D009997:Osmotic Pressure; D018129:Phosphatidylinositol Phosphates / Q000502:physiology*; D012568:Schizosaccharomyces / Q000378:metabolism / Q000502:physiology* / Q000648:ultrastructure; D013172:Spores, Fungal / Q000502:physiology* / Q000648:ultrastructure
chemical_list: D003470:Culture Media; D018129:Phosphatidylinositol Phosphates; C055525:phosphatidylinositol 3-phosphate