title: Functional characterization of an ammonium transporter gene from Lotus japonicus.
abstract: NH(4)(+) is the main product of symbiotic nitrogen fixation and the external concentration of combined nitrogen plays a key regulatory role in all the different step of plant-rhizobia interaction. We report the cloning and characterization of the first member of the ammonium transporter family, LjAMT1;1 from a leguminous plant, Lotus japonicus. Sequence analysis reveals a close relationship to plant transporters of the AMT1 family. The wild type and two mutated versions of LjAMT1;1 were expressed and functionally characterized in yeast. LjAMT1;1 is transcribed in roots, leaves and nodules of L. japonicus plants grown under low nitrogen conditions, consistent with a role in uptake of NH(4)(+) by the plant cells.
authors.affiliation: International Institute of Genetics and Biophysics. Via Marconi 12, 80125, Napoli, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Salvemini
authors.forename: A
authors.initials: A
authors.lastname: Marini
authors.forename: A
authors.initials: A
authors.lastname: Riccio
authors.forename: E J
authors.initials: EJ
authors.lastname: Patriarca
authors.forename: M
authors.initials: M
authors.lastname: Chiurazzi
mesh_terms: D000595:Amino Acid Sequence; D002352:Carrier Proteins / Q000235:genetics* / Q000378:metabolism; D027682:Cation Transport Proteins; D002455:Cell Division / Q000187:drug effects / Q000235:genetics; D018744:DNA, Plant / Q000737:chemistry / Q000235:genetics; D005091:Exons; D017343:Genes, Plant / Q000235:genetics*; D007438:Introns; D008744:Methylamines / Q000378:metabolism / Q000494:pharmacology; D008969:Molecular Sequence Data; D009154:Mutation; D010940:Plant Proteins; D010944:Plants / Q000235:genetics*; D010957:Plasmids / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid
chemical_list: D002352:Carrier Proteins; D027682:Cation Transport Proteins; D018744:DNA, Plant; D008744:Methylamines; D010940:Plant Proteins; C088952:ammonium transporters, plant; C027451:methylamine