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Ammonium and Urea Transporter Inventory of the Selaginella and Physcomitrella Genomes

By Roberto De Michele, Dominique Loqué, Sylvie Lalonde and Wolf B. Frommer


Ammonium and urea are important nitrogen sources for autotrophic organisms. Plant genomes encode several families of specific transporters for these molecules, plus other uptake mechanisms such as aquaporins and ABC transporters. Selaginella and Physcomitrella are representatives of lycophytes and bryophytes, respectively, and the recent completion of their genome sequences provided us with an opportunity for comparative genome studies, with special emphasis on the adaptive processes that accompanied the conquest of dry land and the evolution of a vascular system. Our phylogenetic analysis revealed that the number of genes encoding urea transporters underwent a progressive reduction during evolution, eventually down to a single copy in vascular plants. Conversely, no clear evolutionary pattern was found for ammonium transporters, and their number and distribution in families varies between species. In particular Selaginella, similar to rice, favors the AMT2/MEP family of ammonium transporters over the plant-specific AMT1 type. In comparison, Physcomitrella presents several members belonging to both families

Topics: Plant Science
Publisher: Frontiers Research Foundation
OAI identifier: oai:pubmedcentral.nih.gov:3355718
Provided by: PubMed Central
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    1. (2007). A cytosolic trans-activation domain essential for ammonium uptake.
    2. (2012). A familyofammoniumtransportersin Saccharomyces cerevisiae.
    3. (1998). A PIIlike protein in Arabidopsis: putative role in nitrogen sensing.
    4. (2010). Adjusting ammonium uptake via phosphorylation.
    5. (1979). Amine uniport at the plasmalemma of charophyte cells.1. Current-voltage curves, saturation kinetics,and effects of unstirred layers.
    6. (2004). Ammonium transporter genes in Chlamydomonas: the nitrate-specific regulatory gene Nit2 is involved in Amt1;1 expression.
    7. (2012). Ammonium urea transporters
    8. (2002). An ABC-type,high-affinityureapermease identified in cyanobacteria.
    9. (2007). An ancient genome duplication contributed to the abundance of metabolic genes in the moss Physcomitrella patens.
    10. and Caldwell,M.M.(1990).Rapidphysiologicaladjustmentofrootstolocalized soil enrichment.
    11. and Yamaguchi,J.(2003).Distinctexpression and function of three ammonium transporter genes (OsAMT1;1-1;3) in rice.
    12. andLiu,L.H.(2008).Molecularand physiological aspects of urea transport in higher plants.
    13. (2003). AtDUR3 encodes a new type of high-affinity urea/H+ symporter in Arabidopsis.
    14. (2007). AtDUR3 represents the major transporter for high-affinity urea transportacrosstheplasmamembraneof nitrogen-deficientArabidopsis roots.
    15. (2000). Biochemical aspects of assimilate transfers along the phloem path: N-solutes in lupins.
    16. (2008). Characterization and regulation of PiDur3, a permease involved in the acquisition of urea by the ectomycorrhizal fungus Paxillus involutus.
    17. (2009). CHL1 functions as a nitrate sensor in plants.
    18. (1994). Cloning and expressionof theMEP1geneencoding an ammonium transporter in Saccharomyces cerevisiae.
    19. (2005). Crystal structure of the archaeal ammoniumtransporterAmt-1from Archaeoglobus fulgidus.
    20. (2007). Distinct sensor pathways in the hierarchical control of SNAT2, a putative amino acid transceptor, by aminoacidavailability.J.Biol.Chem.
    21. (2009). Feedback inhibition of ammonium uptake by a phosphodependent allosteric mechanism in Arabidopsis.
    22. (2009). Functioning and evolutionary significance of nutrient transceptors.
    23. (1994). Identification of a high-affinity NH4 + transporter from plants.
    24. (2007). Inorganic nitrogen assimilation in Chlamydomonas.
    25. (2004). Lack of the Rhesus protein Rh1impairsgrowthofthegreenalga Chlamydomonas reinhardtii at high CO2.
    26. (2004). Mechanism of ammonia transport byAmt/MEP/Rh:
    27. (2006). Mechanisms of ammonium transport, accumulation, and retention in ooyctes and yeast cells expressing Arabidopsis AtAMT1;1.
    28. (2011). MEGA5: molecular evolutionary genetics analysis using maximum likelihood, evolutionarydistance,andmaximumparsimony methods.
    29. (2002). Membrane sequestrationof thesignaltransduction protein GlnK by the ammonium transporter AmtB.
    30. (2008). Molecular analysis of physiological responses to changes in nitrogeninamarinemacroalga,Porphyra yezoensis (Rhodophyta).
    31. (2003). Molecular and cellular characterisation of LjAMT2; 1, an ammonium transporter from the model legume Lotus japonicus.
    32. (2009). Molecular basis and regulation of ammonium transporter in rice.
    33. (2011). N-terminal cysteines affect oligomer stability of the allosterically regulated ammonium transporter LeAMT1;1.
    34. N.(2006).Molecularmechanismsof urea transport in plants.
    35. (1985). Nitrate assimilation and translocation by higher-plants – comparativephysiologyandecologicalconsequences.
    36. (2009). Of blood, brains and bacteria, the Amt/Rh transporter family: emerging role of Amt as a unique microbial sensor.
    37. (2009). Pore mutations in ammonium transporter AMT1 with increased electrogenic ammonium transportactivity.J.Biol.Chem.284,
    38. (2007). Regulation of NH4 + transport by essential cross talk between AMT monomers through the carboxyl tails.
    39. (1993). Regulation of the urea active transporter gene (DUR3) in Saccharomyces cerevisiae.
    40. (2004). Regulatory levels for the transport of ammonium in plant roots.
    41. (2005). Representation and high-quality annotation of the Physcomitrella patens transcriptome demonstrates a high proportion of proteins involved in metabolism in mosses.
    42. (2001). Rhesus factors and ammonium: a function in efflux?
    43. (2011). Rice DUR3 mediates highaffinity urea transport and plays an effective role in improvement of urea acquisition and utilization when expressed in Arabidopsis.
    44. (2012). Statement: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
    45. (2007). The crystal structure of the Escherichia coli AmtB-GlnK complex reveals how GlnK regulates the ammonia channel.
    46. (2006). The expanded family of ammonium transporters in the perennial poplar plant.
    47. (2000). The human Rhesus-associated RhAG protein and a kidney homologue promote ammonium transport in yeast.
    48. (2008). The Physcomitrella genome revealsevolutionaryinsightsintothe conquest of land by plants.
    49. (2002). The regulation of ammonium translocation in plants.
    50. (2011). The Selaginella genomeidentifiesgenetic changes associated with the evolution of vascular plants.
    51. (2012). This is an openaccess article distributed under the terms of the Creative Commons Attribution Non Commercial License, which permits non-commercial use, distribution, and reproduction in other forums, provided the original authors and source are credited.
    52. (1999). Three functional transporters for constitutive, diurnally regulated, and starvationinduced uptake of ammonium into Arabidopsis roots.
    53. (2012). tree was constructed by aligning the protein sequences by ClustalW and generated with the Maximum-Likelihood method.
    54. (2002). Uniport of NH4 + by the root hair plasma membrane ammonium transporter LeAMT1;1.
    55. W.,andUdvardi,M.K.(2002).Characterizationof Arabidopsis AtAMT2, a high-affinity ammonium transporter of the plasma membrane.
    56. W.B.(1996).Preferentialexpression of an ammonium transporter and of two putative nitrate transporters in root hairs of tomato.

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