BT CornCarla Barrios

Jim Taylor

BACILLUS THURINGIENSIS IS A SPECIES OF BACTERIA THAT PRODUCES (CRYSTAL-LIKE)PROTEINS THAT ARE TOXIC TO CERTAIN INSECTS.

BT History Japanese biologist Shigetane Ishiwatar isolated the bacterium Bacillus thuringiensis (Bt) in 1901.

In 1915, Ernest Berliner reported the existence of a crystal within Bt.

Farmers started to use Bt as a pesticide in 1920, but only killed flour moth.

Bt as a pesticide had limitations such as it is washed away by rain and degraded by UV light.

In 1958 Bt was used commercially in United States and was registered as a pesticide to the EPA in 1961.

In 1977 thirteen Bt strains had been described and were toxic to certain species of lepidopteran larvae.

In the 1980's use of Bt increased when insects became increasingly resistant to the synthetic insecticides.

Scientists and environmentalists became aware that the chemicals were harming the environment.

The first genetically engineered plant, corn, was registered with the EPA in 1995.

How BT works

When a susceptible insect ingests plant material containing the Bt toxin, pores in a section of the midgut of the insect are formed. This then leads to paralysis of the gut and within two to three days, death of the insect.

Advantages Bt does not kill beneficial insects such as honeybees.

Bt is essentially nontoxic to people, pets and wildlife.

Bt does not has negative impact on the environment.

Bt provides more than 99% control of first generation European corn borer larvae.

How it’s madeDIY BT CORN

Overview

Planning Gene: Bt

a Promoters - 35S or PEP Carboxylase

b. Coding Regions - Cry1A(b), Cry1A(c), or Crygc

c. Expression - If 35S promoter; then ECB resistance in all tissues all the time.

If PEP Carb_ promoter, then ECB resistance in actively photosynthesizing (green) tissues on y.

Gene: Roundup resistance

a Promoter - 35S

b. Coding Region - EPSPS enzyme (Roundup resistance) + CTP region to send protein to chloroplasts

c. Expression - Roundup resistance in all plant tissues all the time.

The Process

Isolating the gene

The Genes

Selecting restriction enzymes

The Vector

Building the

Plasmid

Getting it into the maize cell

The CornT0940A Hi-II Parent A (for producing embryogenic callus cultures)

(also known by these names: Hi IIA, Hi-II Parent A, HiII A, HiIIA, High 2, High II, High-2, High-II, High2, HighII,T0940A, T940A Hi-II Parent A)

Partially inbred line selected out of a cross between A188 and B73 Obtained from C. Armstrong. For producing embryogenic (Type II) callus cultures.

Excise the embryos by inserting the narrow end of a sharpened spatula between the endosperm and pericarp

Growing it out

Summary Impact

Building

ImpactBacillus thuringiensis is a species of bacteria that produces (crystal-like)proteins that are toxic to certain insects.

Japanese biologist Shigetane Ishiwatar isolated the bacterium Bacillus thuringiensis (Bt) in 1901.

The first genetically engineered plant, corn, was registered with the EPA in 1995.

Bt provides more than 99% control of first generation European corn borer larvae

Overview

Partial list of references. The full list is available upon request.

1. National Center for Biotechnology Information - http://www.ncbi.nlm.nih.gov/

2. SnapGene tutorial videos - http://www.snapgene.com/support/tutorial_videos

3. New England Biolabs - https://www.neb.com/tools-and-resources/interactive-tools/dna-sequences-and-maps-tool

4. MaizeGDB! - http://alpha.maizegdb.org/

5. http://gmoinfo.jrc.ec.europa.eu/gmp_report.aspx?CurNot=B/RO/09/03

6. http://www.ent.iastate.edu/pest/cornborer/

7. http://www.fda.gov/Food/FoodScienceResearch/Biotechnology/Submissions/ucm121422.htm

8. http://www.fda.gov/food/foodscienceresearch/biotechnology/submissions/ucm161150.htm

9. http://www.livestrong.com/article/373830-how-to-choose-restriction-enzymes/