Lecture 13 Chapter 8 Genes and traits of interest II Neal Stewart

Discussion questions 1. Other than the products discussed in this chapter, what other sorts of genes or strategies might be useful in engineering transgenic plants resistant to insects or pathogens? 2. Golden Rice producing provitamin A has the potential to help many impoverished people who might benefit from eating it. Although application of this technology is supported by many people and organizations, there are also some who oppose the technology. Considering their possible motivations and potential biases, discuss some of the reasons that groups have come out in favor or in opposition to Golden Rice. 3. What are the potential benefits of producing pharmaceutical proteins in plants? What are some of the disadvantages or potential dangers? 4. Animal genes can be inserted into plants and expressed. Would you be opposed to eating foods from plants expressing proteins encoded by animal genes? By human genes? Discuss the reasons for your answers.

Insect resistance

Controlling Colorado potato beetle is not easy

Bt corn

Bt cotton

Stewart, Genetically Modified Planet 2004 Bacillus thuringiensis

Bt Cry structure I III II Stewart, Genetically Modified Planet 2004

Figure 8.3

Insect midgut cells that have bound Bt toxin. Same gut cells a few hours later– note the damage and leakage. Bt toxin Stewart, Genetically Modified Planet 2004

Insect midgut cells that have bound Bt toxin. Bt Mutated receptors cannot bind Bt toxin. Receptors are not present– cells cannot bind Bt Stewart, Genetically Modified Planet 2004

Different Bt Crys Cry 1s—kills caterpillars (lepidoptera) Cry 2s—kills caterpillars (lepidoptera) Cry 3s—kills beetles (coleoptera) Canola plant expresses a Bt cry1Ac gene

Transgenic disease resistance Viruses (yes) Bacteria (no) Fungi (no) Nematodes (no)

Figure 8.4

Stewart, Genetically Modified Planet 2004 RNA virus structure

Discussion question Other than the products discussed in this chapter, what other sorts of genes or strategies might be useful in engineering transgenic plants resistant to insects or pathogens?

Figure 8.5

Second generation Output traits

Improved nutrition, better foods Golden rice Modified oils from oilseeds Vitamin E enhancements

Golden rice: producing provitamin A

Biotechnologist of the day: Ingo Potrykus

Figure 8.6

Golden Rice producing provitamin A has the potential to help many impoverished people who might benefit from eating it. Although application of this technology is supported by many people and organizations, there are also some who oppose the technology. Considering their possible motivations and potential biases, discuss some of the reasons that groups have come out in favor or in opposition to Golden Rice.

Third generation Non-traditional products

Examples Pharmaceuticals Oral vaccines Phytoremediation Phytosensors Biofuels

Plant-made pharmaceuticals aka Molecular pharming Duckweed Corn Genetic Engineering Protein Purification Grow in lab Or field Oral vaccine– eat the fruit, or purify the vaccine  pill or injection

Fraunhofer USA: one plant- based platform to produce pharmaceutical proteins: vaccines oCGFW1WOFTY

What are the potential benefits of producing pharmaceutical proteins in plants? What are some of the disadvantages or potential dangers?

Phytorediation example How to remediate mercury in soil

Phytosensor example: plants to detect landmines

induction Using inducible promoter/GFP fusions No TNT +TNT Phytosensor example: plants to detect landmines

So, transgenic plants could be used in a lot of applications… Are there any we should avoid?