Arsenic, cadmium, lead, and mercury are toxic elements that are almost ubiquitously present at low levels in the environment because of anthropogenic influences. Dietary intake of plant-derived food represents a major fraction of potentially health-threatening human exposure, especially to arsenic and cadmium. In the interest of better food safety, it is important to reduce toxic element accumulation in crops. A molecular understanding of the pathways responsible for this accumulation can enable the development of crop varieties with strongly reduced concentrations of toxic elements in their edible parts. Such understanding is rapidly progressing for arsenic and cadmium but is in its infancy for lead and mercury. Basic discoveries have been made in , rice, and other models, and most advances in crops have been made in rice. Proteins mediating the uptake of arsenic and cadmium have been identified, and the speciation and biotransformations of arsenic are now understood. Factors controlling the efficiency of root-to-shoot translocation and the partitioning of toxic elements through the rice node have also been identified.


Article metrics loading...

Loading full text...

Full text loading...


Literature Cited

  1. Abe T, Nonoue Y, Ono N, Omoteno M, Kuramata M. 1.  et al. 2013. Detection of QTLs to reduce cadmium content in rice grains using LAC23/Koshihikari chromosome segment substitution lines. Breed. Sci. 63:284–91 [Google Scholar]
  2. Åkesson A, Barregard L, Bergdahl IA, Nordberg GF, Nordberg M, Skerfving S. 2.  2014. Non-renal effects and the risk assessment of environmental cadmium exposure. Environ. Health Perspect. 122:431–38 [Google Scholar]
  3. Álvarez-Fernández A, Díaz-Benito P, Abadía A, Lopez-Millan A-F, Abadía J. 3.  2014. Metal species involved in long distance metal transport in plants. Front. Plant Sci. 5:105 [Google Scholar]
  4. Arao T, Ae N. 4.  2003. Genotypic variations in cadmium levels of rice grain. Soil Sci. Plant Nutr. 49:473–79 [Google Scholar]
  5. Arao T, Kawasaki A, Baba K, Matsumoto S. 5.  2011. Effects of arsenic compound amendment on arsenic speciation in rice grain. Environ. Sci. Technol. 45:1291–97 [Google Scholar]
  6. Argüello JM, Raimunda D, González-Guerrero M. 6.  2012. Metal transport across biomembranes: emerging models for a distinct chemistry. J. Biol. Chem. 287:13510–17 [Google Scholar]
  7. 7. ATSDR (Agency Toxic Subst. Dis. Regist.) 2013. Priority List of Hazardous Substances http://www.atsdr.cdc.gov/spl [Google Scholar]
  8. Batista BL, Nigar M, Mestrot A, Rocha BA, Júnior FB. 8.  et al. 2014. Identification and quantification of phytochelatins in roots of rice to long-term exposure: evidence of individual role on arsenic accumulation and translocation. J. Exp. Bot. 65:1467–79 [Google Scholar]
  9. Bienert GP, Thorsen M, Schüssler MD, Nilsson HR, Wagner A. 9.  et al. 2008. A subgroup of plant aquaporins facilitate the bi-directional diffusion of As(OH)3 and Sb(OH)3 across membranes. BMC Biol. 6:26 [Google Scholar]
  10. Bouis HE, Welch RM. 10.  2010. Biofortification—a sustainable agricultural strategy for reducing micronutrient malnutrition in the global south. Crop Sci. 50:S20–32 [Google Scholar]
  11. Bovenkamp GL, Prange A, Schumacher W, Ham K, Smith AP, Hormes J. 11.  2013. Lead uptake in diverse plant families: a study applying X-ray absorption near edge spectroscopy. Environ. Sci. Technol. 47:4375–82 [Google Scholar]
  12. Canfield RL, Henderson CR, Cory-Slechta DA, Cox C, Jusko TA, Lanphear BP. 12.  2003. Intellectual impairment in children with blood lead concentrations below 10 μg per deciliter. N. Engl. J. Med. 348:1517–26 [Google Scholar]
  13. Carey A, Norton GJ, Deacon C, Scheckel KG, Lombi E. 13.  et al. 2011. Phloem transport of arsenic species from flag leaf to grain during grain filling. New Phytol. 192:87–98 [Google Scholar]
  14. Carey A, Scheckel K, Lombi E, Newville M, Choi Y. 14.  et al. 2010. Grain unloading of arsenic species in rice. Plant Physiol. 152:309–19 [Google Scholar]
  15. Carrasco-Gil S, Álvarez-Fernández A, Sobrino-Plata J, Millán R, Carpena-Ruiz RO. 15.  et al. 2011. Complexation of Hg with phytochelatins is important for plant Hg tolerance. Plant Cell Environ. 34:778–91 [Google Scholar]
  16. Chao D-Y, Chen Y, Chen J, Shi S, Chen Z. 16.  et al. 2014. Genome-wide association mapping identifies a new arsenate reductase enzyme critical for limiting arsenic accumulation in plants. PLOS Biol. 12:e1002009Along with Ref. 109, identified the first As(V) reductase from plants and demonstrated the importance of As(V) reduction for controlling As accumulation. [Google Scholar]
  17. Chao D-Y, Silva A, Baxter I, Huang YS, Nordborg M. 17.  et al. 2012. Genome-wide association studies identify heavy metal ATPase3 as the primary determinant of natural variation in leaf cadmium in Arabidopsis thaliana. PLOS Genet. 8:e1002923 [Google Scholar]
  18. Chen Y, Moore KL, Miller AJ, McGrath SP, Ma JF, Zhao F-J. 18.  2015. The role of nodes in arsenic storage and distribution in rice. J. Exp. Bot. 66:3717–24 [Google Scholar]
  19. Cheng F, Zhao N, Xu H, Li Y, Zhang W. 19.  et al. 2006. Cadmium and lead contamination in japonica rice grains and its variation among the different locations in Southeast China. Sci. Total Environ. 359:156–66 [Google Scholar]
  20. Clemens S. 20.  2006. Toxic metal accumulation, responses to exposure and mechanisms of tolerance in plants. Biochimie 88:1707–19 [Google Scholar]
  21. Clemens S, Aarts MGM, Thomine S, Verbruggen N. 21.  2013. Plant science: the key to preventing slow cadmium poisoning. Trends Plant Sci. 18:92–99 [Google Scholar]
  22. Clemens S, Antosiewicz DM, Ward JM, Schachtman DP, Schroeder JI. 22.  1998. The plant cDNA LCT1 mediates the uptake of calcium and cadmium in yeast. PNAS 95:12043–48 [Google Scholar]
  23. Clemens S, Palmgren MG, Krämer U. 23.  2002. A long way ahead: understanding and engineering plant metal accumulation. Trends Plant Sci. 7:309–15 [Google Scholar]
  24. Clemens S, Persoh D. 24.  2009. Multi-tasking phytochelatin synthases. Plant Sci. 177:266–71 [Google Scholar]
  25. Cobbett C, Goldsbrough P. 25.  2002. Phytochelatins and metallothioneins: roles in heavy metal detoxification and homeostasis. Annu. Rev. Plant Biol. 53:159–82 [Google Scholar]
  26. Colangelo EP, Guerinot ML. 26.  2006. Put the metal to the petal: metal uptake and transport throughout plants. Curr. Opin. Plant Biol. 9:322–30 [Google Scholar]
  27. Connolly EL, Fett JP, Guerinot ML. 27.  2002. Expression of the IRT1 metal transporter is controlled by metals at the levels of transcript and protein accumulation. Plant Cell 14:1347–57 [Google Scholar]
  28. Dalton TP, He L, Wang B, Miller ML, Jin L. 28.  et al. 2005. Identification of mouse SLC39a8 as the transporter responsible for cadmium-induced toxicity in the testis. PNAS 102:3401–6 [Google Scholar]
  29. 29. EFSA (Eur. Food Saf. Auth.) 2009. Scientific opinion of the Panel on Contaminants in the Food Chain on a request from the European Commission on cadmium in food. EFSA J. 980:1–139 [Google Scholar]
  30. 30. EFSA (Eur. Food Saf. Auth.) 2010. Scientific opinion on lead in food. EFSA J. 8:1570 [Google Scholar]
  31. 31. EFSA (Eur. Food Saf. Auth.) 2012. Scientific opinion on the risk for public health related to the presence of mercury and methylmercury in food. EFSA J. 10:2985 [Google Scholar]
  32. 32. FAO (Food Agric. Organ. UN), WHO (World Health Organ.) 2010. Evaluation of certain food additives and contaminants: seventy-third report of the Joint FAO/WHO Expert Committee on Food Additives WHO Tech. Report Ser. 960, WHO, Geneva, Switz. http://whqlibdoc.who.int/trs/WHO_TRS_960_eng.pdf [Google Scholar]
  33. Fischer S, Kühnlenz T, Thieme M, Schmidt H, Clemens S. 33.  2014. Analysis of plant Pb tolerance at realistic submicromolar concentrations demonstrates the role of phytochelatin synthesis for Pb detoxification. Environ. Sci. Technol. 48:7552–59 [Google Scholar]
  34. Fujimaki S, Suzui N, Ishioka NS, Kawachi N, Ito S. 34.  et al. 2010. Tracing cadmium from culture to spikelet: noninvasive imaging and quantitative characterization of absorption, transport, and accumulation of cadmium in an intact rice plant. Plant Physiol. 152:1796–806Monitored the movement of Cd in an intact plant and provided evidence for accumulation in the nodes of rice plants. [Google Scholar]
  35. Gilbert-Diamond D, Cottingham KL, Gruber JF, Punshon T, Sayarath V. 35.  et al. 2011. Rice consumption contributes to arsenic exposure in US women. PNAS 108:20656–60 [Google Scholar]
  36. Goyer RA. 36.  1997. Toxic and essential metal interactions. Annu. Rev. Nutr. 17:37–50 [Google Scholar]
  37. Grant CA, Clarke JM, Duguid S, Chaney RL. 37.  2008. Selection and breeding of plant cultivars to minimize cadmium accumulation. Sci. Total Environ. 390:301–10 [Google Scholar]
  38. Gunshin H, Mackenzie B, Berger UV, Gunshin Y, Romero MF. 38.  et al. 1997. Cloning and characterization of a mammalian proton-coupled metal-ion transporter. Nature 388:482–88 [Google Scholar]
  39. Hanikenne M, Talke IN, Haydon MJ, Lanz C, Nolte A. 39.  et al. 2008. Evolution of metal hyperaccumulation required cis-regulatory changes and triplication of HMA4. Nature 453:391–95 [Google Scholar]
  40. Harris NS, Taylor GJ. 40.  2013. Cadmium uptake and partitioning in durum wheat during grain filling. BMC Plant Biol. 13:103 [Google Scholar]
  41. Hart H. 41.  1930. Nicolas Theodore de Saussure. Plant Physiol. 5:424–29 [Google Scholar]
  42. Harvey CF, Swartz CH, Badruzzaman ABM, Keon-Blute N, Yu W. 42.  et al. 2002. Arsenic mobility and groundwater extraction in Bangladesh. Science 298:1602–6 [Google Scholar]
  43. Hatfield DL, Tsuji PA, Carlson BA, Gladyshev VN. 43.  2014. Selenium and selenocysteine: roles in cancer, health, and development. Trends Biochem. Sci. 39:112–20 [Google Scholar]
  44. Hoch E, Lin W, Chai J, Hershfinkel M, Fu D, Sekler I. 44.  2012. Histidine pairing at the metal transport site of mammalian ZnT transporters controls Zn2+ over Cd2+ selectivity. PNAS 109:7202–7 [Google Scholar]
  45. Hughes MF. 45.  2002. Arsenic toxicity and potential mechanisms of action. Toxicol. Lett. 133:1–16 [Google Scholar]
  46. Ishikawa S, Ae N, Yano M. 46.  2005. Chromosomal regions with quantitative trait loci controlling cadmium concentration in brown rice (Oryza sativa). New Phytol. 168:345–50 [Google Scholar]
  47. Ishikawa S, Ishimaru Y, Igura M, Kuramata M, Abe T. 47.  et al. 2012. Ion-beam irradiation, gene identification, and marker-assisted breeding in the development of low-cadmium rice. PNAS 109:19166–71Along with Ref. 111, identified the major uptake pathway for Cd in rice. [Google Scholar]
  48. Ishikawa S, Suzui N, Ito-Tanabata S, Ishii S, Igura M. 48.  et al. 2011. Real-time imaging and analysis of differences in cadmium dynamics in rice cultivars (Oryza sativa) using positron-emitting 107Cd tracer. BMC Plant Biol. 11:172 [Google Scholar]
  49. Järup L. 49.  2003. Hazards of heavy metal contamination. Br. Med. Bull. 68:167–82 [Google Scholar]
  50. Järup L, Akesson A. 50.  2009. Current status of cadmium as an environmental health problem. Toxicol. Appl. Pharmacol. 238:201–8 [Google Scholar]
  51. Jia Y, Huang H, Zhong M, Wang F-H, Zhang L-M, Zhu Y-G. 51.  2013. Microbial arsenic methylation in soil and rice rhizosphere. Environ. Sci. Technol. 47:3141–48 [Google Scholar]
  52. Johanning J, Strasdeit H. 52.  1998. A coordination-chemical basis for the biological function of the phytochelatins. Angew. Chem. Int. Ed. 37:2464–66 [Google Scholar]
  53. Jomova K, Jenisova Z, Feszterova M, Baros S, Liska J. 53.  et al. 2011. Arsenic: toxicity, oxidative stress and human disease. J. Appl. Toxicol. 31:95–107 [Google Scholar]
  54. Kato M, Ishikawa S, Inagaki K, Chiba K, Hayashi H. 54.  et al. 2010. Possible chemical forms of cadmium and varietal differences in cadmium concentrations in the phloem sap of rice plants (Oryza sativa L.). Soil Sci. Plant Nutr. 56:839–47 [Google Scholar]
  55. Khan MA, Castro-Guerrero NA, Mendoza-Cózatl D. 55.  2014. Moving toward a precise nutrition: preferential loading of seeds with essential nutrients over non-essential toxic elements. Front. Plant Sci. 5:51 [Google Scholar]
  56. Kobayashi NI, Tanoi K, Hirose A, Nakanishi TM. 56.  2013. Characterization of rapid intervascular transport of cadmium in rice stem by radioisotope imaging. J. Exp. Bot. 64:507–17 [Google Scholar]
  57. Kobayashi T, Nishizawa NK. 57.  2012. Iron uptake, translocation, and regulation in higher plants. Annu. Rev. Plant Biol. 63:131–52 [Google Scholar]
  58. Kopittke PM, Blamey FPC, Asher CJ, Menzies NW. 58.  2010. Trace metal phytotoxicity in solution culture: a review. J. Exp. Bot. 61:945–54 [Google Scholar]
  59. Kopittke PM, de Jonge MD, Wang P, McKenna BA, Lombi E. 59.  et al. 2014. Laterally resolved speciation of arsenic in roots of wheat and rice using fluorescence-XANES imaging. New Phytol. 201:1251–62 [Google Scholar]
  60. Korshunova YO, Eide D, Clark WG, Guerinot ML, Pakrasi HB. 60.  1999. The IRT1 protein from Arabidopsis thaliana is a metal transporter with a broad substrate range. Plant Mol. Biol. 40:37–44 [Google Scholar]
  61. Krämer U. 61.  2010. Metal hyperaccumulation in plants. Annu. Rev. Plant Biol. 61:517–34 [Google Scholar]
  62. Kubo K, Watanabe Y, Oyanagi A, Kaneko S, Chono M. 62.  et al. 2008. Cadmium concentration in grains of Japanese wheat cultivars: genotypic difference and relationship with agronomic characteristics. Plant Prod. Sci. 11:243–49 [Google Scholar]
  63. Landrigan PJ, Schechter CB, Lipton JM, Fahs MC, Schwartz J. 63.  2002. Environmental pollutants and disease in American children: estimates of morbidity, mortality, and costs for lead poisoning, asthma, cancer, and developmental disabilities. Environ. Health Perspect. 110:721–28 [Google Scholar]
  64. Li R, Ago Y, Liu W, Mitani N, Feldmann J. 64.  et al. 2009. The rice aquaporin Lsi1 mediates uptake of methylated arsenic species. Plant Physiol. 150:2071–80 [Google Scholar]
  65. Li WC, Tse HF. 65.  2015. Health risk and significance of mercury in the environment. Environ. Sci. Pollut. Res. 22:192–201 [Google Scholar]
  66. Liu W, Schat H, Bliek M, Chen Y, McGrath SP. 66.  et al. 2012. Knocking out ACR2 does not affect arsenic redox status in Arabidopsis thaliana: implications for As detoxification and accumulation in plants. PLOS ONE 7:e42408 [Google Scholar]
  67. Lomax C, Liu W-J, Wu L, Xue K, Xiong J. 67.  et al. 2012. Methylated arsenic species in plants originate from soil microorganisms. New Phytol. 193:665–72 [Google Scholar]
  68. Lombi E, Scheckel KG, Pallon J, Carey AM, Zhu YG, Meharg AA. 68.  2009. Speciation and distribution of arsenic and localization of nutrients in rice grains. New Phytol. 184:193–201 [Google Scholar]
  69. Ma JF, Tamai K, Yamaji N, Mitani N, Konishi S. 69.  et al. 2006. A silicon transporter in rice. Nature 440:688–91 [Google Scholar]
  70. Ma JF, Yamaji N. 70.  2015. A cooperative system of silicon transport in plants. Trends Plant Sci. 20:435–42 [Google Scholar]
  71. Ma JF, Yamaji N, Mitani N, Tamai K, Konishi S. 71.  et al. 2007. An efflux transporter of silicon in rice. Nature 448:209–212 [Google Scholar]
  72. Ma JF, Yamaji N, Mitani N, Xu X-Y, Su Y-H. 72.  et al. 2008. Transporters of arsenite in rice and their role in arsenic accumulation in rice grain. PNAS 105:9931–35Demonstrated the major role of silicon transporters and the silicon pathway for As uptake in rice. [Google Scholar]
  73. Malagoli M, Schiavon M, dall'Acqua S, Pilon-Smits EAH. 73.  2015. Effects of selenium biofortification on crop nutritional quality. Front. Plant Sci. 6:280 [Google Scholar]
  74. Maret W, Moulis J-M. 74.  2013. The bioinorganic chemistry of cadmium in the context of its toxicity. Met. Ions Life Sci. 11:1–29 [Google Scholar]
  75. McLaughlin MJ, Parker DR, Clarke JM. 75.  1999. Metals and micronutrients—food safety issues. Field Crops Res. 60:143–63 [Google Scholar]
  76. Meharg AA, Hartley-Whitaker J. 76.  2002. Arsenic uptake and metabolism in arsenic resistant and nonresistant plant species. New Phytol. 154:29–43 [Google Scholar]
  77. Meharg AA, Macnair M. 77.  1992. Suppression of the high-affinity phosphate-uptake system—a mechanism. J. Exp. Bot. 43:519–24 [Google Scholar]
  78. Meharg AA, Norton G, Deacon C, Williams P, Adomako EE. 78.  et al. 2013. Variation in rice cadmium related to human exposure. Environ. Sci. Technol. 47:5613–18 [Google Scholar]
  79. Meharg AA, Rahman M. 79.  2003. Arsenic contamination of Bangladesh paddy field soils: implications for rice contribution to arsenic consumption. Environ. Sci. Technol. 37:229–34 [Google Scholar]
  80. Mendoza-Cózatl DG, Butko E, Springer F, Torpey JW, Komives EA. 80.  et al. 2008. Identification of high levels of phytochelatins, glutathione and cadmium in the phloem sap of Brassica napus. A role for thiol-peptides in the long-distance transport of cadmium and the effect of cadmium on iron translocation. Plant J. 54:249–59 [Google Scholar]
  81. Mendoza-Cózatl DG, Jobe TO, Hauser F, Schroeder JI. 81.  2011. Long-distance transport, vacuolar sequestration, tolerance, and transcriptional responses induced by cadmium and arsenic. Curr. Opin. Plant Biol. 14:554–62 [Google Scholar]
  82. Meng B, Feng X, Qiu G, Liang P, Li P. 82.  et al. 2011. The process of methylmercury accumulation in rice (Oryza sativa L.). Environ. Sci. Technol. 45:2711–17 [Google Scholar]
  83. Mergler D, Anderson HA, Chan LHM, Mahaffey KR, Murray M. 83.  et al. 2007. Methylmercury exposure and health effects in humans: a worldwide concern. Ambio 36:3–11 [Google Scholar]
  84. Mills RF, Peaston KA, Runions J, Williams LE. 84.  2012. HvHMA2, a P1b-ATPase from barley, is highly conserved among cereals and functions in Zn and Cd transport. PLOS ONE 7:e42640 [Google Scholar]
  85. Mitani-Ueno N, Yamaji N, Zhao F-J, Ma JF. 85.  2011. The aromatic/arginine selectivity filter of NIP aquaporins plays a critical role in substrate selectivity for silicon, boron, and arsenic. J. Exp. Bot. 62:4391–98 [Google Scholar]
  86. Miyadate H, Adachi S, Hiraizumi A, Tezuka K, Nakazawa N. 86.  et al. 2010. OsHMA3, a P1b-type of ATPase affects root-to-shoot cadmium translocation in rice by mediating efflux into vacuoles. New Phytol. 189:190–99Along with Ref. 124, identified OsHMA3 as underlying a major QTL for grain Cd in rice. [Google Scholar]
  87. Moore KL, Chen Y, van de Meene AML, Hughes L, Liu W. 87.  et al. 2014. Combined NanoSIMS and synchrotron X-ray fluorescence reveal distinct cellular and subcellular distribution patterns of trace elements in rice tissues. New Phytol. 201:104–15Provided information on As localization and speciation with exceptional cellular and subcellular resolution using state-of-the-art elemental imaging techniques. [Google Scholar]
  88. Moore KL, Schröder M, Lombi E, Zhao F-J, McGrath SP. 88.  et al. 2010. NanoSIMS analysis of arsenic and selenium in cereal grain. New Phytol. 185:434–45 [Google Scholar]
  89. Moore KL, Schröder M, Wu Z, Martin BGH, Hawes CR. 89.  et al. 2011. High-resolution secondary ion mass spectrometry reveals the contrasting subcellular distribution of arsenic and silicon in rice roots. Plant Physiol. 156:913–24 [Google Scholar]
  90. Mustroph A, Zanetti ME, Jang CJH, Holtan HE, Repetti PP. 90.  et al. 2009. Profiling translatomes of discrete cell populations resolves altered cellular priorities during hypoxia in Arabidopsis. PNAS 106:18843–48 [Google Scholar]
  91. Nocito FF, Lancilli C, Dendena B, Lucchini G, Sacchi GA. 91.  2011. Cadmium retention in rice roots is influenced by cadmium availability, chelation and translocation. Plant Cell Environ. 34:994–1008 [Google Scholar]
  92. Norton GJ, Deacon CM, Mestrot A, Feldmann J, Jenkins P. 92.  et al. 2015. Cadmium and lead in vegetable and fruit produce selected from specific regional areas of the UK. Sci. Total Environ. 533:520–27 [Google Scholar]
  93. Norton GJ, Douglas A, Lahner B, Yakubova E, Guerinot ML. 93.  et al. 2014. Genome wide association mapping of grain arsenic, copper, molybdenum and zinc in rice (Oryza sativa L.) grown at four international field sites. PLOS ONE 9:e89685 [Google Scholar]
  94. Norton GJ, Duan G, Dasgupta T, Islam MR, Lei M. 94.  et al. 2009. Environmental and genetic control of arsenic accumulation and speciation in rice grain: comparing a range of common cultivars grown in contaminated sites across Bangladesh, China, and India. Environ. Sci. Technol. 43:8381–86 [Google Scholar]
  95. Norton GJ, Pinson SRM, Alexander J, Mckay S, Hansen H. 95.  et al. 2012. Variation in grain arsenic assessed in a diverse panel of rice (Oryza sativa) grown in multiple sites. New Phytol. 193:650–64 [Google Scholar]
  96. Norton GJ, Williams PN, Adomako EE, Price AH, Zhu Y. 96.  et al. 2014. Lead in rice: analysis of baseline lead levels in market and field collected rice grains. Sci. Total Environ. 485:428–34 [Google Scholar]
  97. Nriagu JO. 97.  1998. Tales told in lead. Science 281:1622–23 [Google Scholar]
  98. Olsen LI, Palmgren MG. 98.  2014. Many rivers to cross: the journey of zinc from soil to seed. Front. Plant Sci. 5:30 [Google Scholar]
  99. Park J, Song W-Y, Ko D, Eom Y, Hansen TH. 99.  et al. 2011. The phytochelatin transporters AtABCC1 and AtABCC2 mediate tolerance to cadmium and mercury. Plant J. 69:278–88 [Google Scholar]
  100. Peralta-Videa JR, Lopez ML, Narayan M, Saupe G, Gardea-Torresdey J. 100.  2009. The biochemistry of environmental heavy metal uptake by plants: implications for the food chain. Int. J. Biochem. Cell Biol. 41:1665–77 [Google Scholar]
  101. Pickering IJ, Prince RC, George MJ, Smith RD, George GN, Salt DE. 101.  2000. Reduction and coordination of arsenic in Indian mustard. Plant Physiol. 122:1171–78 [Google Scholar]
  102. Pinson SRM, Tarpley L, Yan W, Yeater K, Lahner B. 102.  et al. 2015. Worldwide genetic diversity for mineral element concentrations in rice grain. Crop Sci. 55:294–311 [Google Scholar]
  103. Pirrone N, Cinnirella S, Feng X, Finkelman RB, Friedli HR. 103.  et al. 2010. Global mercury emissions to the atmosphere from anthropogenic and natural sources. Atmos. Chem. Phys. 10:5951–64 [Google Scholar]
  104. Pottier M, Oomen R, Picco C, Giraudat J, Scholz-Starke J. 104.  et al. 2015. Identification of mutations allowing Natural Resistance Associated Macrophage Proteins (NRAMP) to discriminate against cadmium. Plant J. 83:625–37 [Google Scholar]
  105. Raab A, Schat H, Meharg AA, Feldmann J. 105.  2005. Uptake, translocation and transformation of arsenate and arsenite in sunflower (Helianthus annuus): formation of arsenic-phytochelatin complexes during exposure to high arsenic concentrations. New Phytol. 168:551–58 [Google Scholar]
  106. Raab A, Williams PN, Meharg A, Feldmann J. 106.  2007. Uptake and translocation of inorganic and methylated arsenic species by plants. Environ. Chem. 4:197–203 [Google Scholar]
  107. Rothenberg SE, Windham-Myers L, Creswell JE. 107.  2014. Rice methylmercury exposure and mitigation: a comprehensive review. Environ. Res. 133:407–23 [Google Scholar]
  108. Salt DE, Baxter I, Lahner B. 108.  2008. Ionomics and the study of the plant ionome. Annu. Rev. Plant Biol. 59:709–33 [Google Scholar]
  109. Sánchez-Bermejo E, Castrillo G, del Llano B, Navarro C, Zarco-Fernández S. 109.  et al. 2014. Natural variation in arsenate tolerance identifies an arsenate reductase in Arabidopsis thaliana. Nat. Commun. 5:4617Along with Ref. 16, identified the first As(V) reductase from plants and demonstrated the importance of As(V) reduction for As tolerance. [Google Scholar]
  110. Sasaki A, Yamaji N, Ma JF. 110.  2014. Overexpression of OsHMA3 enhances Cd tolerance and expression of Zn transporter genes in rice. J. Exp. Bot. 65:6013–21 [Google Scholar]
  111. Sasaki A, Yamaji N, Yokosho K, Ma JF. 111.  2012. Nramp5 is a major transporter responsible for manganese and cadmium uptake in rice. Plant Cell 24:2155–67Along with Ref. 47, identified a Mn transporter as the major uptake pathway for Cd in rice. [Google Scholar]
  112. Satoh-Nagasawa N, Mori M, Nakazawa N, Kawamoto T, Nagato Y. 112.  et al. 2012. Mutations in rice (Oryza sativa) heavy metal ATPase 2 (OsHMA2) restrict the translocation of zinc and cadmium. Plant Cell Physiol. 53:213–24 [Google Scholar]
  113. Schmöger M, Oven M, Grill E. 113.  2000. Detoxification of arsenic by phytochelatins in plants. Plant Physiol. 122:793–801 [Google Scholar]
  114. Shin H, Shin H-S, Dewbre GR, Harrison MJ. 114.  2004. Phosphate transport in Arabidopsis: Pht1;1 and Pht1;4 play a major role in phosphate acquisition from both low- and high-phosphate environments. Plant J. 39:629–42 [Google Scholar]
  115. Song W-Y, Park J, Mendoza-Cózatl DG, Suter-Grotemeyer M, Shim D. 115.  et al. 2010. Arsenic tolerance in Arabidopsis is mediated by two ABCC-type phytochelatin transporters. PNAS 107:21187–92 [Google Scholar]
  116. Song W-Y, Yamaki T, Yamaji N, Ko D, Jung K-H. 116.  et al. 2014. A rice ABC transporter, OsABCC1, reduces arsenic accumulation in the grain. PNAS 111:15699–704Demonstrated the importance of thiols for As(III) retention in the phloem and the crucial role of the As-PC transporter OsABCC1. [Google Scholar]
  117. Su Y-H, McGrath SP, Zhao F-J. 117.  2010. Rice is more efficient in arsenite uptake and translocation than wheat and barley. Plant Soil 328:27–34 [Google Scholar]
  118. Takahashi R, Ishimaru Y, Senoura T, Shimo H, Ishikawa S. 118.  et al. 2011. The OsNramp1 iron transporter is involved in Cd accumulation in rice. J. Exp. Bot. 62:4843–50 [Google Scholar]
  119. Takahashi R, Ishimaru Y, Shimo H, Ogo Y, Senoura T. 119.  et al. 2012. The OsHMA2 transporter is involved in root-to-shoot translocation of Zn and Cd in rice. Plant Cell Environ. 35:1948–57 [Google Scholar]
  120. Tanaka K, Fujimaki S, Fujiwara T, Yoneyama T, Hayashi H. 120.  2007. Quantitative estimation of the contribution of the phloem in cadmium transport to grains in rice plants (Oryza sativa L.). Soil Sci. Plant Nutr. 53:72–77 [Google Scholar]
  121. Thomine S, Wang R, Ward JM, Crawford NM, Schroeder JI. 121.  2000. Cadmium and iron transport by members of a plant metal transporter family in Arabidopsis with homology to Nramp genes. PNAS 97:4991–96 [Google Scholar]
  122. Ueno D, Kono I, Yokosho K, Ando T, Yano M, Ma JF. 122.  2009. A major quantitative trait locus controlling cadmium translocation in rice (Oryza sativa). New Phytol. 182:644–53 [Google Scholar]
  123. Ueno D, Koyama E, Yamaji N, Ma JF. 123.  2011. Physiological, genetic, and molecular characterization of a high-Cd-accumulating rice cultivar, Jarjan. J. Exp. Bot. 62:2265–72 [Google Scholar]
  124. Ueno D, Yamaji N, Kono I, Huang CF, Ando T. 124.  et al. 2010. Gene limiting cadmium accumulation in rice. PNAS 107:16500–505Along with Ref. 86, identified OsHMA3 as underlying a major QTL for grain Cd and demonstrated that OsHMA3 overexpression lowers grain Cd. [Google Scholar]
  125. 125. UNEP (UN Environ. Programme) 2008. Draft final review of scientific information on cadmium http://www.unep.org/hazardoussubstances/Portals/9/Lead_Cadmium/docs/Interim_reviews/Final_UNEP_Cadmium_review_Nov_2008.pdf [Google Scholar]
  126. Uraguchi S, Fujiwara T. 126.  2013. Rice breaks ground for cadmium-free cereals. Curr. Opin. Plant Biol. 16:328–34 [Google Scholar]
  127. Uraguchi S, Kamiya T, Sakamoto T, Kasai K, Sato Y. 127.  et al. 2011. Low-affinity cation transporter (OsLCT1) regulates cadmium transport into rice grains. PNAS 108:20959–64Demonstrated the importance of the transporter OsLCT1 for xylem-to-phloem transfer and grain accumulation of Cd in rice. [Google Scholar]
  128. Uraguchi S, Mori S, Kuramata M, Kawasaki A, Arao T, Ishikawa S. 128.  2009. Root-to-shoot Cd translocation via the xylem is the major process determining shoot and grain cadmium accumulation in rice. J. Exp. Bot. 60:2677–88 [Google Scholar]
  129. Verbruggen N, Hermans C, Schat H. 129.  2009. Mechanisms to cope with arsenic or cadmium excess in plants. Curr. Opin. Plant Biol. 12:364–72 [Google Scholar]
  130. Wang J, Fang W, Yang Z, Yuan J, Zhu Y, Yu H. 130.  2007. Inter- and intraspecific variations of cadmium accumulation of 13 leafy vegetable species in a greenhouse experiment. J. Agric. Food Chem. 55:9118–23 [Google Scholar]
  131. White PJ, Broadley MR. 131.  2005. Biofortifying crops with essential mineral elements. Trends Plant Sci. 10:586–93 [Google Scholar]
  132. Williams PN, Lei M, Sun G, Huang Q, Lu Y. 132.  et al. 2009. Occurrence and partitioning of cadmium, arsenic and lead in mine impacted paddy rice: Hunan, China. Environ. Sci. Technol. 43:637–42 [Google Scholar]
  133. Williams PN, Villada A, Deacon C, Raab A, Figuerola J. 133.  et al. 2007. Greatly enhanced arsenic shoot assimilation in rice leads to elevated grain levels compared to wheat and barley. Environ. Sci. Technol. 41:6854–59 [Google Scholar]
  134. Wong CKE, Cobbett CS. 134.  2009. HMA P-type ATPases are the major mechanism for root-to-shoot Cd translocation in Arabidopsis thaliana. New Phytol. 181:71–78 [Google Scholar]
  135. Wu D, Sato K, Ma JF. 135.  2015. Genome-wide association mapping of cadmium accumulation in different organs of barley. New Phytol. 208:817–29 [Google Scholar]
  136. Wu Z, Ren H, McGrath SP, Wu P, Zhao F-J. 136.  2011. Investigating the contribution of the phosphate transport pathway to arsenic accumulation in rice. Plant Physiol. 157:498–508 [Google Scholar]
  137. Xu XY, McGrath SP, Zhao F-J. 137.  2007. Rapid reduction of arsenate in the medium mediated by plant roots. New Phytol. 176:590–99 [Google Scholar]
  138. Yamaguchi N, Ishikawa S, Abe T, Baba K, Arao T, Terada Y. 138.  2012. Role of the node in controlling traffic of cadmium, zinc, and manganese in rice. J. Exp. Bot. 63:2729–37 [Google Scholar]
  139. Yamaji N, Ma JF. 139.  2014. The node, a hub for mineral nutrient distribution in graminaceous plants. Trends Plant Sci. 19:556–63 [Google Scholar]
  140. Yamaji N, Xia J, Mitani-Ueno N, Yokosho K, Ma JF. 140.  2013. Preferential delivery of zinc to developing tissues in rice is mediated by P-type heavy metal ATPase OsHMA2. Plant Physiol. 162:927–39 [Google Scholar]
  141. Yang M, Zhang Y, Zhang L, Hu J, Zhang X. 141.  et al. 2014. OsNramp5 contributes to manganese translocation and distribution in rice shoots. J. Exp. Bot. 65:4849–61 [Google Scholar]
  142. Ye J, Rensing C, Rosen BP, Zhu Y-G. 142.  2012. Arsenic biomethylation by photosynthetic organisms. Trends Plant Sci. 17:155–62 [Google Scholar]
  143. Ye W-L, Wood BA, Stroud JL, Andralojc PJ, Raab A. 143.  et al. 2010. Arsenic speciation in phloem and xylem exudates of castor bean. Plant Physiol. 154:1505–13 [Google Scholar]
  144. Zhao F-J, Ago Y, Mitani N, Li R-Y, Su Y-H. 144.  et al. 2010. The role of the rice aquaporin Lsi1 in arsenite efflux from roots. New Phytol. 186:392–99 [Google Scholar]
  145. Zhao F-J, Harris E, Yan J, Ma J, Wu L. 145.  et al. 2013. Arsenic methylation in soils and its relationship with microbial arsM abundance and diversity, and As speciation in rice. Environ. Sci. Technol. 47:7147–54 [Google Scholar]
  146. Zhao F-J, Ma JF, Meharg AA, McGrath SP. 146.  2009. Arsenic uptake and metabolism in plants. New Phytol. 181:777–94 [Google Scholar]
  147. Zhao F-J, Ma Y, Zhu Y-G, Tang Z, McGrath SP. 147.  2015. Soil contamination in China: current status and mitigation strategies. Environ. Sci. Technol. 49:750–59 [Google Scholar]
  148. Zhao F-J, McGrath SP, Meharg AA. 148.  2010. Arsenic as a food chain contaminant: mechanisms of plant uptake and metabolism and mitigation strategies. Annu. Rev. Plant Biol. 61:535–59 [Google Scholar]
  149. Zhao F-J, Moore KL, Lombi E, Zhu Y-G. 149.  2014. Imaging element distribution and speciation in plant cells. Trends Plant Sci. 19:183–92 [Google Scholar]
  150. Zhu Y-G, Yoshinaga M, Zhao F-J, Rosen BP. 150.  2014. Earth abides arsenic biotransformations. Annu. Rev. Earth Planet. Sci. 42:443–67 [Google Scholar]

Data & Media loading...

  • Article Type: Review Article
This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error