1. The Science of Transgenics Phil McClean Department of Plant Science North Dakota State University The Sociological, Economic, and Ethical Impact of Transgenic Organisms Workshop Fargo, ND February 21, 2003

2. Transgenics are a Biotechnology Product How about some definitions Biotechnology - General Definition The application of technology to improve a biological organism Biotechnology - Detailed Definition The application of the technology to improve the biological function of an organism by adding genes from another organisms

4. What is a transgenic? Transgene – the genetically engineered gene added to a species Ex. – modified EPSP synthase gene (encodes a protein that functions even when plant is treated with Roundup) Transgenic – an organism containing a transgene introduced by technological (not breeding) methods Ex. – Roundup Ready Crops Concept Based on the Term Transgene

5. We can develop organisms that express a “novel” trait not normally found in the species Why are transgenics important? Extended shelf-life tomato (Flavr-Savr) Herbicide resistant soybean (Roundup Ready)

10. Next Generation of Ag Biotech Products Source: Minnesota Microscopy Society Golden Rice – increased Vitamin A content (but not without controversy) transgene = three pathway enzymes Sunflower – white mold resistance transgene = oxalate oxidase from wheat

11. Turfgrass – herbicide resistance; slower growing (= reduced mowing) Bio Steel – spider silk expressed in goats; used to make soft-body bullet proof vests (Nexia)

12. Biotechnology is Not Just on the Farm Disease Treatment Diagnostics Environmental Cleanup Human Applications

15. Environmental Applications Bioremediation - cleanup contaminated sites; uses microbes designed to degrade the pollution Indicator bacteria – contamination can be detected in the environment

16. Tooth decay – engineered Streptococcus mutans, the bacteria that destroys enamel Future Health-related Biotech Products Vaccines – herpes, hepatitis C, AIDS, malaria

22. Wheat Rye Triticale X Interspecific Cross New species, but NOT biotechnology products

24. ATTCGA ATT G GA Susceptible Normal Gene Resistant Mutant Gene Mutagenesis Treatment Mutagenesis Changes the DNA Sequence

27. + Glyphosate X Roundup Sensitive Plants X X Without amino acids, plant dies X Shikimic acid + Phosphoenol pyruvate 3-Enolpyruvyl shikimic acid-5-phosphate (EPSP) Plant EPSP synthase Aromatic amino acids

28. Bacterial EPSP synthase Shikimic acid + Phosphoenol pyruvate 3-enolpyruvyl shikimic acid-5-phosphate (EPSP) Aromatic amino acids Roundup Resistant Plants + Glyphosate With amino acids, plant lives RoundUp has no effect; enzyme is resistant to herbicide

30.  -Carotene Pathway Problem in Plants IPP Geranylgeranyl diphosphate Phytoene Lycopene  -carotene (vitamin A precursor) Phytoene synthase Phytoene desaturase Lycopene-beta-cyclase ξ-carotene desaturase Problem: Rice lacks these enzymes Normal Vitamin A “ Deficient” Rice

31. The Golden Rice Solution Daffodil gene Single bacterial gene; performs both functions Daffodil gene  -Carotene Pathway Genes Added IPP Geranylgeranyl diphosphate Phytoene Lycopene  -carotene (vitamin A precursor) Phytoene synthase Phytoene desaturase Lycopene-beta-cyclase ξ-carotene desaturase Vitamin A Pathway is complete and functional Golden Rice

32. Introducing the Gene or Developing Transgenics Steps 1. Create transformation cassette 2. Introduce and select for transformants

36. The Lab Steps

37. The Next Test Is The Field Herbicide Resistance Non-transgenics Transgenics

38. Final Test of the Transgenic Consumer Acceptance RoundUp Ready Corn Before After