Plant Molecular Biology

, Volume 29, Issue 6, pp 1181–1196

The macrophage-specific membrane protein Nramp controlling natural resistance to infections in mice has homologues expressed in the root system of plants

  • Abdelmajid Belouchi
  • Mathieu Cellier
  • Tony Kwan
  • Hargurdeep S. Saini
  • Gilles Leroux
  • Philippe Gros
Research article


In mice, natural resistance or susceptibility to infection with Mycobacteria, Salmonella, and Leishmania is controlled by a gene named Bcg. Bcg regulates the capacity of macrophages to limit intracellular replication of the ingested parasites, and is believed to regulate a key bactericidal mechanism of this cell. Recently, we have cloned the Bcg gene and shown that it encodes a novel macrophage-specific membrane protein designated Nramp. A routine search of the public databases for sequences homologous to Nramp identified 3 expressed sequence tags (EST) that show strong similarities to the mammalian protein.

We report the identification and cloning of a full-length cDNA clone corresponding to a plant homologue (OsNramp1) of mammalian Nramp. Predicted amino acid sequence analysis of the plant protein indicates a remarkable degree of similarity (60% homology) with its mammalian counterpart, including identical number, position, and composition of transmembrane domains, glycosylation signals, and consensus transport motif, suggesting an identical overall secondary structure and membrane organization for the two proteins. This high degree of structural similarity indicates that the two proteins may be functionally related, possibly through a common mechanism of transport. RNA hybridization studies and RT-PCR analyses indicate that OsNramp1 mRNA is expressed primarily in roots and only at very low levels in leaves/stem. DNA hybridization studies indicate that OsNramp1 is not a single gene, but rather forms part of a novel gene family which has several members in all plants tested including cereals such as rice, wheat, and corn, and also in common weed species. The striking degree of conservation between the macrophage-specific mammalian Nramp and its OsNramp1 plant homologue is discussed with respect to possible implications in the metabolism of nitrate in both organisms.

Key words

gene family rice root-specific gene expression membrane protein Crna nitrate transport 


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  1. 1.
    Altschul SF, Gish W, Miller W, Myers EW, Lipman DJ: Basic local alignment search tool. J Mol Biol 215: 403–410 (1990).Google Scholar
  2. 2.
    Anderson MP, Gregory RJ, Thompson S, Souza DW, Paul S, Mulligan RC, Smith AE, Welch MJ: Demonstration that CFTR is a Cl channel by alteration of its anion selectivity. Science 253: 202–205 (1991).Google Scholar
  3. 3.
    Aslam M, Travis RL, Huffaker RC: Comparative kinetics and reciprocal inhibition of nitrate and nitrite uptake in roots of uninduced and induced barley seedlings. Plant Physiol 99: 1124–1133 (1992).Google Scholar
  4. 4.
    Bairoch A: The PROSITE dictionary of sites and patterns in proteins: its current status. Nucl Acids Res 21: 3097–4103 (1993).Google Scholar
  5. 5.
    Barton CH, White JK, Roach TIA, Blackwell JM: NH2-terminal sequence of a macrophage-expressed natural resistance-associated macrophage protein (Nramp) encodes a proline/serine-rich putative Src homology 3-binding domain. J Exp Med 179: 1683–1687 (1994).Google Scholar
  6. 6.
    Cellier M, Govoni G, Vidal SM, Kwan T, Groulx N, Liu J, Sanchez F, Skamene E, Schurr E, Gros P: Human natural resistance-associated macrophage protein: cDNA cloning, chromosomal mapping, genomic organization, and tissue-specific expression. J Exp Med 180: 1741–1752 (1994).Google Scholar
  7. 7.
    Chirgwin JM, Prybyla AA, MacDonald RJ, Rutter WJ: Isolation of biologically active ribonucleic acid from sources enriched in ribonuclease. Biochemistry 18: 5294–5299 (1979).Google Scholar
  8. 8.
    Crawford NM, Arst Jr HN: The molecular genetics of nitrate assimilation in fungi and plants. Annu Rev Genet 27: 115–146 (1993).Google Scholar
  9. 9.
    Dassa E, Hofnung M: Sequence of gene MalG in E. Coli K12: Homologies between integral membrane components from binding protein-dependent transport systems. EMBO J 4: 2287–2293 (1985).Google Scholar
  10. 10.
    Devereux J: The GCG sequence analysis software package, version 7.0. Genetics Computer Group, University Reseaarch Park, Madison, WI (1991).Google Scholar
  11. 11.
    Doddema H, Telkamp GP: Uptake of nitrate by mutants of Arabidopsis thaliana, disturbed in uptake or reduction of nitrate II kinetics. Physiol Plant 45: 332–338 (1979).Google Scholar
  12. 12.
    Eisenberg D, Schwarz E, Komaromy M, Wall R: Analysis of membrane and surface protein sequences with the hydrophobic moment plot. J Mol Biol 179: 125–142 (1984).Google Scholar
  13. 13.
    Epstein DJ, Vekemans M, Gros P: splotch Sp 2H, a mutation affecting development of the mouse neural tube, shows a deletion within the paired homeodomain of Pax-3. Cell 67: 767–774 (1991).Google Scholar
  14. 14.
    Feinberg AP, Vogelstein BA: technique for radiolabelling DNA restriction endonucleases fragments to high specific activity. Anal Biochem 132: 6–13 (1984).Google Scholar
  15. 15.
    Glass AD, Shaff JE, Kochian LV: Studies of the uptake of nitrate in barley. IV. Electrophysiology. Plant Physiol 99: 456–463 (1992).Google Scholar
  16. 16.
    Goto Y, Buschman E, Skamene E: Regulation of host resistance to Mycobacterium intracellulare in vivo and in vitro by the Bcg gene. Immunogenetics 30: 218–221 (1989).Google Scholar
  17. 17.
    Green S, Nacy CA, Meltzer M: Cytokine-induced synthesis of nitrogen oxides in macrophages: a protective host response to Leishmania and other intracellular pathogens. J Leuk Biol 50: 93–103 (1991).Google Scholar
  18. 18.
    Gros P, Skamene E, Forget A: Genetic control of natural resistance to Mycobacterium bovis BCG. J Immunol 127: 2417–2421 (1981).Google Scholar
  19. 19.
    Gros P, Skamene E, Forget A: Cellular mechanisms of genetically-controlled host resistance to Mycobacterium bovis (BCG). J Immunol 131: 1966–1973 (1983).Google Scholar
  20. 20.
    Gruenheid S, Cellier M, Vidal SM, Gros P: Identification and characterization of a second mouse Nramp gene. Genomics 25: 514–525 (1995).Google Scholar
  21. 21.
    Hole D, Emran AM, Fares Y, Drew MC: Induction of nitrate transport in maize roots, and kinetics of influx, measured with nitrogen-13. Plant Physiol 93: 642–647 (1990).Google Scholar
  22. 22.
    Jacobsen KS, Breivold E, Hornes E: Purification of mRNA directly from crude plant tissues in 15 minutes using magnetic oligo dT microspheres. Nucl Acids Res 18: 3669 (1990).Google Scholar
  23. 23.
    Kerppola RE, Ames GF-L: Topology of the hydrophobic membrane-bound components of the histidine periplasmic permease. Comparison with other members of the family. J Biol Chem 267: 2329–2336 (1992).Google Scholar
  24. 24.
    Kieferle S, Fong P, Bens M, Vandewalle A, Jentsch TJ: Two highly homologous members of the CIC chloride channel family in both rat and human kidney. Proc Natl Acad Sci USA 91: 6943–6947 (1994).Google Scholar
  25. 25.
    Kyte J, Doolittle RF: A simple method for displaying the hydropathy of a protein. J Mol Biol 157: 105–132 (1982).Google Scholar
  26. 26.
    Lissner CR, Swanson RN, O'Brien AD: Genetic control of the innate resistance of mice to Salmonella typhimurium: expression of the Ity gene in peritoneal and splenic macrophages isolated in vitro. J Immunol 131: 3006–3013 (1983).Google Scholar
  27. 27.
    Malo D, Schurr E, Epstein DJ, Vekemans M, Skamene E, Gros P: The host resistance locus Bcg is tightly linked to a group of cytoskeleton-associated protein genes that include villin and desmin. Genomics 10: 356–364 (1991).Google Scholar
  28. 28.
    Malo D, Vidal SM, Hu J, Skamene E, Gros P: High resolution linkage map in the vicinity of the host resistance locus Bcg. Genomics 16: 655–663 (1993).Google Scholar
  29. 29.
    Malo D, Vidal SM, Lieman JH, Ward DC, Gros P: Physical delineation of the minimal chromosomal segment encompassing the murine host resistance locus Bcg. Genomics 17: 667–675 (1993).Google Scholar
  30. 30.
    Malo D, Vogan K, Vidal SM, Hu J, Cellier M, Schurr E, Fuks A, Morgan K, Gros P: Haplotype mapping and sequence analysis of the mouse Nramp gene predict susceptibility to infection with intracellular parasites. Genomics 23: 51–61 (1994).Google Scholar
  31. 31.
    Mangalan H: Striding the turf of the gang of four. Trends Genet 18: 187–188 (1993).Google Scholar
  32. 32.
    Nathan C: Nitric oxide as a secretory product of mammalian cells. FASEB J 6: 3051–3061 (1992).Google Scholar
  33. 33.
    Nathan CF, Hibbs JB: Role of nitric oxyde synthesis in macrophage antimicrobial activity. Curr Opin Immunol 3: 65–70 (1991).Google Scholar
  34. 34.
    Noonan KE, Rominson IB: mRNA phenotyping by enzymatic amplification of randomly primed cDNA. Nucl Acids Res 16: 10366 (1988).Google Scholar
  35. 35.
    Ruiz-Cristin J, Briskin DP: Characterization of a H+/N O3 symport associated with plasma membrane vesicles of maize roots using 36CIO3 as a radiotracer analog. Arch Biochem Biophys 285: 74–82 (1991).Google Scholar
  36. 36.
    Sahin-Toth M, Dunten RL, Gonzales A, Kaback HR: Functional interactions between putative intramembrane charged residues in the lactose permease of Escherichia coli. Proc Natl Acad Sci USA 89: 10547–10551 (1992).Google Scholar
  37. 37.
    Sambrook J, Fritsch EF, Maniatis T: ‘Molecular Cloning: A Laboratory Manual’, 2nd ed. Cold Spring Harbor Laboratory Press, Cold Spring Harbor, NY (1989).Google Scholar
  38. 38.
    Sanger F, Nicklen S, Coulson AR: DNA sequencing with chain termination inhibitors. Proc Natl Acad Sci USA 74: 5463–5467 (1977).Google Scholar
  39. 39.
    Saurin W, Koster W, Dassa E: Bacterial binding protein-dependent permeases: characterization of distinctive signatures for functionally related integral cytoplasmic membrane proteins. Mol Microbiol 12: 993–1004 (1994).Google Scholar
  40. 40.
    Siddiqi MY, Glass ADM, Ruth TJ, Fernando M: Studies on the regulation of nitrate influx by barley using 13N O3 . Plant Physiol 90: 806–813 (1989).Google Scholar
  41. 41.
    Siddiqi MY, Glass ADM, Ruth TJ, Rufty TW: Studies of the uptake of nitrate in barley. Plant Physiol 93: 1426–1432 (1990).Google Scholar
  42. 42.
    Skamene E, Pietrangeli CE: Genetics of the immune response to infectious pathogens. Curr Onin Immunol 3: 511–517 (1991).Google Scholar
  43. 43.
    Stach JL, Gros P, Forget A, Skamene E: Phenotypic expression of genetically controlled natural resistance to Mycobacterium bovis (BCG) J Immunol 132: 888–892 (1984).Google Scholar
  44. 44.
    Stuehr DJ, Nathan CF: Nitric oxide. A macrophage product responsible for cytostasis and respiratory inhibition in tumor target cells. J Exp Med 169: 1543–1555 (1989).Google Scholar
  45. 45.
    Tsay Y-F, Schroeder JI, Feldmann KA, Crawford NM: The herbicide sensitivity gene CHL1 of Arabidopsis encodes a nitrate-inducible nitrate transporter. Cell 72: 705–713 (1993).Google Scholar
  46. 46.
    Unkles SE, Hawker KL, Grieve C, Campbell EI, Van Montague P, Kinghorn JR: crnA encodes a nitrate transporter in Aspergillus nidulans. Proc Natl Acad Sci USA 88: 204–208 (1991).Google Scholar
  47. 47.
    Vidal SM, Malo D, Vogan K, Skamene E, Gros P: Natural resistance to infection with intracellular parasites: Isolation of a candidate for Bcg. Cell 73: 469–485 (1993).Google Scholar
  48. 48.
    Vidal SM, Tremblay M, Govoni G, Gauthier S, Sebastiani G, Malo D, Olivier M, Skamene E, Jothy S, Gros P: The Ity/Lsh/Bcg locus: natural resistance to infection with intracellular parasites is abrogated by disruption of the Nramp1 gene. J Exp Med, in press (1995).Google Scholar

Copyright information

© Kluwer Academic Publishers 1995

Authors and Affiliations

  • Abdelmajid Belouchi
    • 1
  • Mathieu Cellier
    • 1
  • Tony Kwan
    • 1
  • Hargurdeep S. Saini
    • 2
  • Gilles Leroux
    • 3
  • Philippe Gros
    • 1
  1. 1.Department of BiochemistryMcGill UniversityMontréalCanada
  2. 2.Institut de Recherche en Biologie VégétaleUniversité de MontréalMontréalCanada
  3. 3.Département de PhytologieUniversité LavalSte-FoyCanada

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