Gene Design

Question 1

dicot or monocot

tobacco

Answer 1

Dicot

Question 2

dicot or monocot

Cotton

Answer 2

Dicot

Question 3

dicot or monocot

Soybean

Answer 3

Dicot

Question 4

dicot or monocot

Legumes

Answer 4

Dicot

Question 5

dicot or monocot

Arabidopsis

Answer 5

Dicot

Question 6

dicot or monocot

Wheat

Answer 6

monocot

Question 7

dicot or monocot

corn

Answer 7

monocot

Question 8

dicot or monocot

Rice

Answer 8

monocot

Question 9

dicot or monocot

Barley

Answer 9

dicot or monocot

Question 10

how does agrobacterium mediated transfer work

Answer 10

Ti plasmid to allow transfer of T-DNA section containing transgene to plant, bacteria incubated with leaf discs

Question 11

Cry1

Answer 11

Lepidoptera

Question 12

Cry3

Answer 12

Coleoptera

Question 13

Cry2

Answer 13

Diptera

Question 14

What species produces Cry toxins

Answer 14

Bacillus thuringiensis

Question 15

When was Bt a registered pesticide

Answer 15

1961

Question 16

Cry toxins have a what structure?

What are the domains?

Answer 16

Conserved structure 600aa
3 distinct domains
1-N terminus 7alpha helix membrane insertion pore formation

2- B prism, receptor recognition and binding

3- C terminal antiparallel B sheets receptor recognition and pore formation

Question 17

Digestion of Cry toxins does what

Answer 17

Activates then

Digestion to N terminal 60-70kDa truncated form

“Toxin forms lytic pores in cell membrane of insect guy and once digested (active) indigested (inactive)

Question 18

The toxin binds where?

This process is called ?

Answer 18

To the high affinity receptors in midgut epithelial

• forms pores
• kills e cell

Colliod osmotic lysis

Question 19

What is a protoxin

Answer 19

Proteolyticall cleaved/inbound to receptor = not toxic “protoxin”

NOT SURE TBH Might he wrong

Question 20

Lepidoptera

Answer 20

Butterflies and moths

Question 21

Diptera

Answer 21

Flies and mosquitoes

Question 22

Coleoptera

Answer 22

Beetles and weevils

Question 23

Hymenoptera

Answer 23

Wasps and bees

Question 24

Herbicide res Maize

Round up

Answer 24

Maize = monocot

P - Ubi
FG - aroA (glyphosate red, detoxifies)
T - Nos (nopaline synthase)
MG - nptII kanomycin res

Says for cereals such a maize better to use herbicide selection gene - eg Hydromycin bar gene

Question 25

Aluminium tolerant legumes

Answer 25

P- CamV35s FG- Csb (citrate synthase gene from pseudomonas) - citrate increases too by chelating Al3+ T- NOS nopaline synthase terminator M- NptII neomycin Gene construct in cytoplasm not mitochondria so doesn’t interfere with Krebs cycle

Question 26

Butterfly insecticide res in rice

Answer 26

Rice = monocot P -Ubi FG - Cry1 from bt T - Nos nopaline synthase term P-Ubi FG- CPT1A (protease inhibitor) T-Nos P-Ubi MG- nptII rice :( kanomycin therefore use paromomycin T-Nos

Question 27

Herbicide too cotton

Answer 27

Cotton = Dicot P-CamV35S FG - bar (against glufosinate) T- nos P-CamV35S MG- nptII kanomycin T-nos

Question 28

Tobacco drought/salinity tol

Answer 28

P- SARK (senescence associated receptor protein kinase) promoter TG- IPT (isopentyl transferase, cytokinin biosyn, prevent senescence) T-Nos nopaline syn term P-CamV35s MG- nptII T-Nos

Question 29

Soybean drought tol

Answer 29

P-CamV35s FG- AtZEP (zeaxanthin epoxidase gene makes zeaxanthin precursor to ABA) T- Nos P-CamV35s FG-nptII kanomycin T-nos

Question 30

Example of light inducible promoter

Answer 30

Promoter from cab gene

Question 31

Use what if don’t what expression all over the plant?

Answer 31

Signal transit peptides Can be used to direct the gene construct to the desired part of the plant E.g. chloroplast or endosperm Endosperm useful in rice as a lot of metabolic activity takes place here

Question 32

Drought tol maize

Answer 32

P-Ubi TG- AVP1 (arabidopsis H+-Ppase pump) T-nos P-Ubi MG- bar (herbicide selection w/ PPT)

Question 33

what is a newly developed stacking system

Answer 33

Zhu et al (2017) have developed a transgene stacking vector system (TGSII) which allows the successful transformation of plants (tested in rice) with several genes in one construct, each with their own promotors and terminators.

Question 34

How does the TGSII stacking system work

Answer 34

These utilise antibiotic selection cassettes (nptII) and Cre/loxp-mediated constructs which allows the marker cassette to be removed under tissue-specific promotors, once the transformants have been selected. This allows a marker free gene construct in planta and it also works with agrobacterium transformation. This could be an interesting alternative for a company to try, as it has had proven success with crop such as Astaxanthin bio-engineered rice (Zhu et al. 2018).