GM crops/foods

Question 1

Transgenic approaches: antisense

Answer 1

Antisense Switch switches the terminator and promoter of a gene so that the RNA polymerase produces an antisense RNA strand. This will bind to the complementary mRNA strand, and set off cellular mechanisms that degrade dsRNA

Question 2

Antisense approach example

Answer 2

Lol-p: starch protein in pollen that cause hayfever when exposed by the wind
removed by introducing an antisense complex in ryegrass cells > promoter that is only expressed in pollen

less IgE reactivity

Question 3

Transgenic approaches: co-suppression

Answer 3

unintended consequence of adding in another copy of a gene in the hopes of increasing suppression
-> accidentally produces dsRNA

Question 4

Example of co-suppression

Answer 4

Gly m bd 30 K is a major seed allergen in soy, used a promoter that is only specific to seeds
less reactive sera

Question 5

Transgenic approaches: RNA interference

Answer 5

purposefully adding dsRNA by adding a gene and its inversion on a single strand
is chopped up by dicer, split into mRNA and -RNA
RISC takes -RNA and uses it as a guide, chops up mRNA

Question 6

Example of RNA interference

Answer 6

Mal D 1 is an apple allergen
used a 35S constitutive promoter so that it was expressed everywhere and could be tested for allergen now instead of in 30 years

Question 7

Cottonseed gossypol

Answer 7

a naturally occurring terpenoid toxin that is high in the seed
produced by plant gland
traditional removal led to increased insect susceptibility
RNAi: silence delta-cadinene synthase, has a highly specific reporter to seeds

Question 8

Golden rice

Answer 8

modified to produce beta-carotene (porvitamin A) in the endosperm
not normally present in seeds
need to insert genes to drive each step with enzymes
1. Psy from maize and
2. crtl from soil bacterium

Question 9

Bt corn

Answer 9

ears of grain are made resistant to bullworms are also less susceptible to contaminations by fusarium and fumosin (neurotoxin)