title: A nucleoporin is required for induction of Ca2+ spiking in legume nodule development and essential for rhizobial and fungal symbiosis.
abstract: Nuclear-cytoplasmic partitioning and traffic between cytoplasmic and nuclear compartments are fundamental processes in eukaryotic cells. Nuclear pore complexes mediate transport of proteins, RNAs and ribonucleoprotein particles in and out of the nucleus. Here we present positional cloning of a plant nucleoporin gene, Nup133, essential for a symbiotic signal transduction pathway shared by Rhizobium bacteria and mycorrhizal fungi. Mutation of Nup133 results in a temperature sensitive nodulation deficient phenotype and absence of mycorrhizal colonization. Root nodules developing with reduced frequency at permissive temperatures are ineffective and electron microscopy show that Rhizobium bacteria are not released from infection threads. Measurement of ion fluxes using a calcium-sensitive dye show that Nup133 is required for the Ca2+ spiking normally detectable within minutes after application of purified rhizobial Nod-factor signal molecules to root hairs. Localization of NUP133 in the nuclear envelope of root cells and root hair cells shown with enhanced yellow fluorescent protein fusion proteins suggests a novel role for NUP133 nucleoporins in a rapid nuclear-cytoplasmic communication after host-plant recognition of symbiotic microbes. Our results identify a component of an intriguing signal process requiring interaction at the cell plasma membrane and at intracellular nuclear and plastid organelle-membranes to induce a second messenger.
authors.affiliation: Department of Molecular Biology, University of Aarhus, Gustav Wieds Vej 10 and C.F. Møllers Vej Bldg 130, 8000 Aarhus C, Denmark.
authors.forename: Norihito
authors.initials: N
authors.lastname: Kanamori
authors.forename: Lene Heegaard
authors.initials: LH
authors.lastname: Madsen
authors.forename: Simona
authors.initials: S
authors.lastname: Radutoiu
authors.forename: Mirela
authors.initials: M
authors.lastname: Frantescu
authors.forename: Esben M H
authors.initials: EM
authors.lastname: Quistgaard
authors.forename: Hiroki
authors.initials: H
authors.lastname: Miwa
authors.forename: J Allan
authors.initials: JA
authors.lastname: Downie
authors.forename: Euan K
authors.initials: EK
authors.lastname: James
authors.forename: Hubert H
authors.initials: HH
authors.lastname: Felle
authors.forename: Line Lindegaard
authors.initials: LL
authors.lastname: Haaning
authors.forename: Torben Heick
authors.initials: TH
authors.lastname: Jensen
authors.forename: Shusei
authors.initials: S
authors.lastname: Sato
authors.forename: Yasukazu
authors.initials: Y
authors.lastname: Nakamura
authors.forename: Satoshi
authors.initials: S
authors.lastname: Tabata
authors.forename: Niels
authors.initials: N
authors.lastname: Sandal
authors.forename: Jens
authors.initials: J
authors.lastname: Stougaard
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D002118:Calcium / Q000378:metabolism*; D020013:Calcium Signaling; D002413:Cations, Divalent / Q000378:metabolism; D002467:Cell Nucleus / Q000378:metabolism; D003001:Cloning, Molecular; D007887:Fabaceae / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism / Q000382:microbiology*; D018506:Gene Expression Regulation, Plant / Q000235:genetics; D008969:Molecular Sequence Data; D038821:Mycorrhizae / Q000502:physiology*; D028861:Nuclear Pore Complex Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D010641:Phenotype; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D012231:Rhizobium / Q000502:physiology*; D016415:Sequence Alignment; D013559:Symbiosis
chemical_list: D002413:Cations, Divalent; D028861:Nuclear Pore Complex Proteins; D010940:Plant Proteins; D002118:Calcium