Transgenic strategies for the nutritional enhancement of plants.

The nutrients in the human diet ultimately come from plants. However, all our major food crops lack certain essential vitamins and minerals. Although a varied diet provides adequate nutrition, much of the human population, particularly in developing countries, relies on staple crops, such as rice or maize, which does not provide the full complement of essential nutrients. Malnutrition is a significant public health issue in most of the developing world. One way to address this problem is through the enhancement of staple crops to increase their essential nutrient content. Here, we review the current strategies for the biofortification of crops, including mineral fertilization and conventional breeding but focusing on transgenic approaches which offer the most rapid way to develop high-nutrient commercial cultivars.

[1]  R. Bock,et al.  Contained metabolic engineering in tomatoes by expression of carotenoid biosynthesis genes from the plastid genome. , 2007, The Plant journal : for cell and molecular biology.

[2]  R. Baranski,et al.  Tissue-specific accumulation of carotenoids in carrot roots , 2006, Planta.

[3]  Xiaohong Zhu,et al.  Increased Lysine Synthesis Coupled with a Knockout of Its Catabolism Synergistically Boosts Lysine Content and Also Transregulates the Metabolism of Other Amino Acids in Arabidopsis Seeds Article, publication date, and citation information can be found at www.plantcell.org/cgi/doi/10.1105/tpc.009647 , 2003, The Plant Cell Online.

[4]  Qing Liu,et al.  Metabolic engineering of Arabidopsis to produce nutritionally important DHA in seed oil. , 2005, Functional plant biology : FPB.

[5]  M. Vasconcelos,et al.  Enhanced iron and zinc accumulation in transgenic rice with the ferritin gene , 2003 .

[6]  S. Chakraborty,et al.  Increased nutritive value of transgenic potato by expressing a nonallergenic seed albumin gene from Amaranthus hypochondriacus , 2000 .

[7]  Fumio Matsuda,et al.  High-level tryptophan accumulation in seeds of transgenic rice and its limited effects on agronomic traits and seed metabolite profile. , 2006, Journal of experimental botany.

[8]  H. Hartikainen.  Biogeochemistry of selenium and its impact on food chain quality and human health. , 2005, Journal of trace elements in medicine and biology : organ of the Society for Minerals and Trace Elements.

[9]  T. Higgins,et al.  The redistribution of protein sulfur in transgenic rice expressing a gene for a foreign, sulfur-rich protein. , 2003, The Plant journal : for cell and molecular biology.

[10]  T. Higgins,et al.  Plasticity of seed protein composition in response to nitrogen and sulfur availability. , 2002, Current opinion in plant biology.

[11]  G. Gregorio,et al.  Breeding for Trace Mineral Density in Rice , 2000 .

[12]  C. Nessler,et al.  Metabolic engineering of an alternative pathway for ascorbic acid biosynthesis in plants , 2000, Molecular Breeding.

[13]  B. Larkins,et al.  Molecular genetic approaches to developing quality protein maize. , 2005, Trends in genetics : TIG.

[14]  M. Guerinot,et al.  Expression of the IRT1 Metal Transporter Is Controlled by Metals at the Levels of Transcript and Protein Accumulation Article, publication date, and citation information can be found at www.plantcell.org/cgi/doi/10.1105/tpc.001263. , 2002, The Plant Cell Online.

[15]  Wilhelm Gruissem,et al.  Transfer and Expression of an Artificial Storage Protein (ASP1) Gene in Cassava (Manihot Esculenta Crantz) , 2003, Transgenic Research.

[16]  S. Mori,et al.  Enhanced tolerance of rice to low iron availability in alkaline soils using barley nicotianamine aminotransferase genes , 2001, Nature Biotechnology.

[17]  T. Rocheford,et al.  QTL and candidate genes phytoene synthase and ζ-carotene desaturase associated with the accumulation of carotenoids in maize , 2004, Theoretical and Applied Genetics.

[18]  P. Simon,et al.  QTL analyses reveal clustered loci for accumulation of major provitamin A carotenes and lycopene in carrot roots , 2002, Molecular Genetics and Genomics.

[19]  J. Stangoulis,et al.  Exploiting micronutrient interaction to optimize biofortification programs: the case for inclusion of selenium and iodine in the HarvestPlus program. , 2004, Nutrition reviews.

[20]  Xiao Qiu,et al.  Stepwise engineering to produce high yields of very long-chain polyunsaturated fatty acids in plants , 2005, Nature Biotechnology.

[21]  E. Hinchliffe,et al.  Improving the nutritional value of Golden Rice through increased pro-vitamin A content , 2005, Nature Biotechnology.

[22]  P. Christou,et al.  Progress in plant metabolic engineering. , 2004, Current opinion in biotechnology.

[23]  P. Beyer,et al.  Transgenic rice (Oryza sativa) endosperm expressing daffodil (Narcissus pseudonarcissus) phytoene synthase accumulates phytoene, a key intermediate of provitamin A biosynthesis. , 1997, The Plant journal : for cell and molecular biology.

[24]  P. Christou,et al.  Endosperm-Specific Co-Expression of Recombinant Soybean Ferritin and Aspergillus Phytase in Maize Results in Significant Increases in the Levels of Bioavailable Iron , 2005, Plant Molecular Biology.

[25]  J. Napier,et al.  Biosynthesis of Very-Long-Chain Polyunsaturated Fatty Acids in Transgenic Oilseeds: Constraints on Their Accumulationw⃞ , 2004, The Plant Cell Online.

[26]  S. C. Falco,et al.  Transgenic Canola and Soybean Seeds with Increased Lysine , 1995, Bio/Technology.

[27]  D. DellaPenna,et al.  Elevating the vitamin E content of plants through metabolic engineering. , 1998, Science.

[28]  N. Murai,et al.  The pea seed storage protein legumin was synthesized, processed, and accumulated stably in transgenic rice endosperm , 1997 .

[29]  G. Kishore,et al.  Enhancement of folates in plants through metabolic engineering. , 2004, Proceedings of the National Academy of Sciences of the United States of America.

[30]  S. Toki,et al.  Iron fortification of rice seed by the soybean ferritin gene , 1999, Nature Biotechnology.

[31]  J. Gregory,et al.  Folate biofortification in tomatoes by engineering the pteridine branch of folate synthesis. , 2004, Proceedings of the National Academy of Sciences of the United States of America.

[32]  F. Carrari,et al.  Enhanced Photosynthetic Performance and Growth as a Consequence of Decreasing Mitochondrial Malate Dehydrogenase Activity in Transgenic Tomato Plants1 , 2005, Plant Physiology.

[33]  J. Messing,et al.  Increasing maize seed methionine by mRNA stability. , 2002, The Plant journal : for cell and molecular biology.

[34]  J. Stangoulis,et al.  Selenium concentration in wheat grain: Is there sufficient genotypic variation to use in breeding? , 2005, Plant and Soil.

[35]  P. Beyer,et al.  Golden Rice: introducing the beta-carotene biosynthesis pathway into rice endosperm by genetic engineering to defeat vitamin A deficiency. , 2002, The Journal of nutrition.

[36]  T. Fujiwara,et al.  Sulphur and nitrogen nutrition influence the response of chickpea seeds to an added, transgenic sink for organic sulphur. , 2004, Journal of experimental botany.

[37]  P. Mendes,et al.  myo-Inositol Oxygenase Offers a Possible Entry Point into Plant Ascorbate Biosynthesis1 , 2004, Plant Physiology.

[38]  P. Beyer,et al.  Engineering the provitamin A (beta-carotene) biosynthetic pathway into (carotenoid-free) rice endosperm. , 2000, Science.

[39]  T. Young,et al.  Increasing vitamin C content of plants through enhanced ascorbate recycling , 2003, Proceedings of the National Academy of Sciences of the United States of America.

[40]  I. Cakmak.  Plant nutritional genomics , 2005 .

[41]  B. Eggum,et al.  Enhanced methionine levels and increased nutritive value of seeds of transgenic lupins (Lupinus angustifolius L.) expressing a sunflower seed albumin gene. , 1997, Proceedings of the National Academy of Sciences of the United States of America.

[42]  C. Timmer.  Biotechnology and food systems in developing countries. , 2003, The Journal of nutrition.

[43]  C. Shewmaker,et al.  Isolation and Characterization of Homogentisate Phytyltransferase Genes from Synechocystis sp. PCC 6803 and Arabidopsis , 2002, Plant Physiology.

[44]  P. Christou,et al.  Pea legumin overexpressed in wheat endosperm assembles into an ordered paracrystalline matrix. , 2001, Plant physiology.

[45]  R. Visser,et al.  Particle bombardment and the genetic enhancement of crops: myths and realities , 2005, Molecular Breeding.

[46]  Li Li,et al.  The Cauliflower Or Gene Encodes a DnaJ Cysteine-Rich Domain-Containing Protein That Mediates High Levels of β-Carotene Accumulation[W] , 2006, The Plant Cell Online.

[47]  R. Hurrell,et al.  Potential for increasing the content and bioavailability of Fe, Zn and Ca in plants for human nutrition. , 2000 .

[48]  J. Gregory,et al.  Folate biofortification of tomato fruit , 2007, Proceedings of the National Academy of Sciences.

[49]  J. Napier,et al.  Production of very long chain polyunsaturated omega-3 and omega-6 fatty acids in plants , 2004, Nature Biotechnology.

[50]  Yong-guan Zhu,et al.  Selecting iodine-enriched vegetables and the residual effect of iodate application to soil , 2004, Biological Trace Element Research.

[51]  C. Foyer,et al.  The Function of Ascorbate Oxidase in Tobacco1 , 2003, Plant Physiology.

[52]  V. Raboy,et al.  Progress in breeding low phytate crops. , 2002, The Journal of nutrition.

[53]  P. Beyer,et al.  Metabolic Engineering of Potato Carotenoid Content through Tuber-Specific Overexpression of a Bacterial Mini-Pathway , 2007, PloS one.

[54]  P. Christou,et al.  Constitutive Expression of Soybean Ferritin cDNA Intransgenic Wheat and Rice Results in Increased Iron Levels in Vegetative Tissues but not in Seeds , 2000, Transgenic Research.

[55]  Martin R Broadley,et al.  Biofortifying crops with essential mineral elements. , 2005, Trends in plant science.

[56]  Paul Christou,et al.  The potential of genetically enhanced plants to address food insecurity , 2004, Nutrition Research Reviews.

[57]  Ingo Potrykus,et al.  Fighting Iron Deficiency Anemia with Iron-Rich Rice , 2002, Journal of the American College of Nutrition.

[58]  Alison L. Van Eenennaam,et al.  Engineering Vitamin E Content: From Arabidopsis Mutant to Soy Oil Article, publication date, and citation information can be found at www.plantcell.org/cgi/doi/10.1105/tpc.015875. , 2003, The Plant Cell Online.

[59]  J. Messing,et al.  A new opaque variant of maize by a single dominant RNA-interference-inducing transgene. , 2003, Genetics.

[60]  Steve Millam,et al.  Metabolic engineering of high carotenoid potato tubers containing enhanced levels of beta-carotene and lutein. , 2004, Journal of experimental botany.

[61]  S. Storozhenko,et al.  Folate enhancement in staple crops by metabolic engineering , 2005 .

[62]  J. Geisel.  Folic Acid and Neural Tube Defects in Pregnancy: A Review , 2003, The Journal of perinatal & neonatal nursing.

[63]  Heribert Hirt,et al.  Convergence and divergence of stress-induced mitogen-activated protein kinase signaling pathways at the level of two distinct mitogen-activated protein kinase kinases. , 2002, The Plant cell.

[64]  M. Truksa,et al.  Metabolic Engineering of Plants to Produce Very Long-chain Polyunsaturated Fatty Acids , 2006, Transgenic Research.