title: Cloning of Arabidopsis thaliana phosphatidylinositol synthase and functional expression in the yeast pis mutant.
abstract: It is believed that phosphatidylinositol (PI) metabolism plays a central role in signalling pathways in both animals and higher plants. PI is synthesized from CDP-diacylglycerol (CDP-DG) and myo-inositol by phosphatidylinositol synthase (PI synthase, EC 2.7.8.11). Here we report the identification of a plant cDNA (AtPIS1) encoding a 26 kDa PI synthase from Arabidopsis thaliana. The plant enzyme as deduced from its cDNA sequence shares 35-41% identical amino acids with PI synthases from Saccharomyces cerevisiae and mammals. AtPIS1 functionally complements a mutant of S. cerevisiae with a lesion in PI synthase, and recombinant AtPIS1 protein present in yeast membranes strongly depends on the two principal substrates, myo-inositol and CDP-DG, and requires Mg2+ ions for full activity.
authors.affiliation: Max-Planck-Institute of Molecular Plant Physiology, Golm/Potsdam, Germany.
authors.forename: H W
authors.initials: HW
authors.lastname: Xue
authors.forename: K
authors.initials: K
authors.lastname: Hosaka
authors.forename: G
authors.initials: G
authors.lastname: Plesch
authors.forename: B
authors.initials: B
authors.lastname: Mueller-Roeber
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000201:enzymology / Q000235:genetics*; D029681:Arabidopsis Proteins; D015152:Blotting, Northern; D051607:CDP-Diacylglycerol-Inositol 3-Phosphatidyltransferase; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D005816:Genetic Complementation Test; D008565:Membrane Proteins; D008969:Molecular Sequence Data; D009154:Mutation; D018749:RNA, Plant / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics*; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D014018:Tissue Distribution; D017855:Transferases (Other Substituted Phosphate Groups) / Q000235:genetics*
chemical_list: D029681:Arabidopsis Proteins; D018076:DNA, Complementary; D008565:Membrane Proteins; D018749:RNA, Plant; D017855:Transferases (Other Substituted Phosphate Groups); C496769:ATPIS1 protein, Arabidopsis; D051607:CDP-Diacylglycerol-Inositol 3-Phosphatidyltransferase