Transgenic Research

, Volume 17, Issue 1, pp 59–71 | Cite as

Transgenic maize endosperm containing a milk protein has improved amino acid balance

  • Earl H. Bicar
  • Wendy Woodman-Clikeman
  • Varaporn Sangtong
  • Joan M. Peterson
  • S. Samuel Yang
  • Michael Lee
  • M. Paul ScottEmail author
Original Paper


In order to meet the protein nutrition needs of the world population, greater reliance on plant protein sources will become necessary. The amino acid balance of most plant protein sources does not match the nutritional requirements of monogastric animals, limiting their nutritional value. In cereals, the essential amino acid lysine is deficient. Maize is a major component of human and animal diets worldwide and especially where sources of plant protein are in critical need such as sub-Saharan Africa. To improve the amino acid balance of maize, we developed transgenic maize lines that produce the milk protein α-lactalbumin in the endosperm. Lines in which the transgene was inherited as a single dominant genetic locus were identified. Sibling kernels with or without the transgene were compared to determine the effect of the transgene on kernel traits in lines selected for their high content of α-lactalbumin. Total protein content in endosperm from transgene positive kernels was not significantly different from total protein content in endosperm from transgene negative kernels in three out of four comparisons, whereas the lysine content of the lines examined was 29–47% greater in endosperm from transgene positive kernels. The content of some other amino acids was changed to a lesser extent. Taken together, these changes resulted in the transgenic endosperms having an improved amino acid balance relative to non-transgenic endosperms produced on the same ear. Kernel appearance, weight, density and zein content did not exhibit substantial differences in kernels expressing the transgene when compared to non-expressing siblings. Assessment of the antigenicity and impacts on animal health will be required in order to determine the overall value of this technology.


Transgene Maize α-Lactalbumin Lysine Nutrition Grain 



The authors wish to thank Erik Mottl and Merinda Struthers for technical assistance. Names are necessary to report factually on the available data; however, the USDA neither guarantees nor warrants the standard of the product, and the use of the name by the USDA implies no approval of the product to the exclusion of others that may be suitable. This work was funded in part by an Iowa Corn Promotion Board grant to MPS and ML and by the Raymond F. Baker Center for Plant Breeding. EHB was supported by a fellowship from Pioneer Hibred International awarded to EHB and ML.


  1. Altenbach SB, Kuo CC, Staraci LC, Pearson KW, Wainwright C, Georgescu A, Townsend J (1992) Accumulation of a Brazil nut albumin in seeds of transgenic canola results in enhanced levels of seed protein methionine. Plant Mol Biol 18:235–245PubMedCrossRefGoogle Scholar
  2. Altenbach SB, Pearson KW, Meeker G, Staraci LC, Sun SSM (1989) Enhancement of the methionine content of seed proteins by the expression of a chimeric gene encoding a methionine-rich protein in transgenic plants. Plant Mol Biol 13:513–522PubMedCrossRefGoogle Scholar
  3. AOAC (2002) Method 982.30 E(a,b). In: Official Methods of Analysis, Ed 17, Chapter 45.3.05Google Scholar
  4. Armstrong CL, Green CE, Phillips RL (1991) Development and availability of germplasm with high Type II culture formation response. Maize Genet Coop News 65:92–93Google Scholar
  5. Chakraborty S, Chakraborty N, Datta A (2000) Increased nutritive value of transgenic potato by expressing a nonallergenic seed albumin gene from Amaranthus hypochondriacus. Proc Natl Acad Sci USA 97:3724–3729PubMedCrossRefGoogle Scholar
  6. Chong DKX, Roberts W, Arakawa T, Illes K, Bagi G, Slattery CW, Langridge WHR (1997) Expression of the human milk protein beta-casein in transgenic potato plants. Transgenic Res 6:289–296PubMedCrossRefGoogle Scholar
  7. Das Gupta NA, Alexander LJ, Beattie CW (1992) The sequence of a porcine cDNA encoding ∝-lactalbumin. Gene 110:265–266PubMedCrossRefGoogle Scholar
  8. De Clercq A, Vandewiele M, van Damme J, Guerche P, van Montagu M, Vandekerckhove J, Krebbers E (1990) Stable accumulation of modified 2S albumin seed storage proteins with higher methionine contents in transgenic plants. Plant Physiol 94:970–979PubMedGoogle Scholar
  9. FAO (2003) FAO statistical databases Scholar
  10. FAO/WHO/UNU (1985) Energy and protein requirements. Report of a joint FAO/WHO/UNU Expert Consultation. WHO, GenevaGoogle Scholar
  11. Feinberg AP, Vogelstein B (1983) A technique for radiolabelling DNA restriction endonuclease fragments to high specific activity. Anal Biochem 132:6–13PubMedCrossRefGoogle Scholar
  12. Frame BR, Zhang H, Cocciolone SM, Sidorenko LV, Dietrich CR, Pegg SE, Zhen S, Schnable PS, Wang K (2000) Production of transgenic maize from bombarded Type II callus: effect of gold particle size and callus morphology on transformation efficiency. In Vitro Cell Dev Biol Plant 36:21–29CrossRefGoogle Scholar
  13. Hakansson A, Svensson M, Mossberg Ann K, Sabharwal H, Linse S, Lazou I, Lonnerdal B, Svanborg C (2000) A folding variant of ∝-lactalbumin with bactericidal activity against Streptococcus pneumoniae. Mol Microbiol 35:589–600PubMedCrossRefGoogle Scholar
  14. Hakansson A, Zhivotovsky B, Orrenius S, Sabharwal H, Svanborg C (1995) Apoptosis induced by a human milk protein. Proc Natl Acad Sci USA 92:8064–8068PubMedCrossRefGoogle Scholar
  15. Laemmli UK (1970) Cleavage of structural proteins during assembly of the head of bacteriophage T4. Nature 227:680–685PubMedCrossRefGoogle Scholar
  16. Lai JS, Messing J (2002) Increasing maize seed methionine by mRNA stability. Plant J 30:395–402PubMedCrossRefGoogle Scholar
  17. Matthews BF, Hughes CA (1993) Nutritional improvement of the aspartate family of amino acids in edible crop plants. Amino Acids 4:21–34CrossRefGoogle Scholar
  18. Molvig L, Tabe LM, Eggum BO, Moore AE, Craig S, Spencer D, Higgins TJV (1997) Enhanced methionine levels and increased nutritive value of seeds of transgenic lupins (Lupinus angustifolius L.) expressing a sunflower seed albumin gene. Proc Natl Acad Sci USA 94:8393–8398PubMedCrossRefGoogle Scholar
  19. Nordlee JA, Taylor SL, Townsend JA, Thomas LA, Bush RK (1996) Identification of a Brazil nut allergen in transgenic soybeans. New Engl J Med 334:688–692PubMedCrossRefGoogle Scholar
  20. Permyakov EA, Berliner LJ (2000) ∝-Lactalbumin: structure and function. FEBS Lett 473:269–274PubMedCrossRefGoogle Scholar
  21. Register JC, Peterson DJ, Bell PJ, Bullock WP, Evans EJ, Frame B, Greenland AJ, Higgs NS, Jepson I, Jiao S, Klewnau CJ, Sillick JM, Wilson HM (1994) Structure and function of selectable and non-selectable transgenes in maize after introduction by particle bombardment. Plant Mol Biol 25:951–961PubMedCrossRefGoogle Scholar
  22. Renner E (1988) Milk and dairy products in human nutrition. Volkswirtschaftlicher Verlag, MunchenGoogle Scholar
  23. Saghai-Maroof MA, Soliman KM, Jorgensen RA, Allard RW (1984) Ribosomal DNA spacer-length polymorphisms in barley: Mendelian inheritance, chromosomal location and population dynamics. Proc Natl Acad Sci USA 81:8014–8019PubMedCrossRefGoogle Scholar
  24. Scott MP, Bicar EH (2003) Biotechnology enhanced crops for improved health. Animal Science Symposium, CanadaGoogle Scholar
  25. Scott MP, Peterson JM, Sangtong V, Moran, D, Guillumine, P-H (2007) A wheat genomic DNA fragment reduces pollen transmission in maize transgenes by reducing pollen viability. Transgenic Res  doi: 10.1007/s11248-006-9055-x
  26. Southern EM (1975) Detection of specific sequences among DNA fragments separated by gel electrophoresis. J Mol Biol 98:503–517PubMedCrossRefGoogle Scholar
  27. Svensson M, Sabharwal H, Hakansson A, Mossberg Ann K, Lipniunas P, Leffler H, Svanborg C, Linse S (1999) Molecular characterization of ∝-lactalbumin folding variants that induce apoptosis in tumor cells. J Biol Chem 274:6388–6396PubMedCrossRefGoogle Scholar
  28. Takase K, Hagiwara K (1998) Expression of human ∝-lactalbumin in transgenic tobacco. J Biochem 123:440–444PubMedGoogle Scholar
  29. Taylor S (1992) Chemistry and detection of food allergens. Food Technol 46:148–152Google Scholar
  30. Wilson CM (1991) Multiple zeins from maize endosperms characterized by reversed-phase High Performance Liquid Chromatography. Plant Physiol 95:777–786PubMedCrossRefGoogle Scholar
  31. Woo Y-M, Hu DW-N, Larkins BA, Jung R (2001) Genomics analysis of genes expressed in maize endosperm identifies novel seed proteins and clarifies patterns of zein gene expression. Plant Cell 13:2297–2317PubMedCrossRefGoogle Scholar
  32. Yang S-H, Moran DL, Jia H-W, Bicar EH, Lee M, Scott MP (2002) Expression of a synthetic porcine ∝-lactalbumin gene in the kernels of transgenic maize. Transgenic Res 11:11–20PubMedCrossRefGoogle Scholar
  33. Ye F, Signer ER (1996) RIGS (repeat-induced gene silencing) in Arabidopsis is transcriptional and alters chromatin configuration. Proc Natl Acad Sci USA 93:10881–10886PubMedCrossRefGoogle Scholar
  34. Yu J, Peng P, Zhang X, Zhao Q, Zhy D, Sun X, Liu J, Ao G (2004) Seed-specific expression of a lysine rich protein sb401 gene significantly increases both lysine and total protein content in maize seeds. Mol Breed 14:1–7CrossRefGoogle Scholar
  35. Zhong GY, Peterson D, Delaney DE, Bailey M, Witcher DR, Register JC III, Bond D, Li CP, Marshall L, Kulisek E, Ritland D, Meyer T, Hood EE, Howard JA (1999) Commercial production of aprotinin in transgenic maize seeds. Mol Breed 5:345–356CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media B.V. 2007

Authors and Affiliations

  • Earl H. Bicar
    • 1
  • Wendy Woodman-Clikeman
    • 1
  • Varaporn Sangtong
    • 1
  • Joan M. Peterson
    • 2
  • S. Samuel Yang
    • 3
  • Michael Lee
    • 1
  • M. Paul Scott
    • 4
    • 5
    Email author
  1. 1.Agronomy Department, The Raymond F. Baker Center for Plant BreedingIowa State UniversityAmesUSA
  2. 2.Food Science and Human NutritionIowa State UniversityAmesUSA
  3. 3.Interdepartmental Genetics Graduate ProgramIowa State UniversityAmesUSA
  4. 4.USDA-ARS, Corn Insects and Crop Genetics Research UnitAmesUSA
  5. 5.Iowa State UniversityAmesUSA

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