Plant genetic engineering

Question 1

What is the bacteria that causes crown gall and hairy root diseases in plants

Answer 1

Agrobacterium tumefaciens (must remember spelling) is a soil bacteria + carries a Ti plasmid (tumour inducing plasmid)

Question 2

How does agrobacterium tumefaciens affect the plants?

Answer 2

bacteria enter plants through wounds or other mtds and transforms the T-DNA (in Ti plasmid) into plant cells.

The plant cells grow in a disorganised way which creates swollen galls

Question 3

What does T-DNA consist of?
(Refer to slides for much better illustration)

Answer 3

Auxin -> codes for auxin + makes plant cell grow bigger
Cytokinin -> codes for cytokinin + makes cell divide
opine -> nutrient molecules only agrobacterium use (cuz they carry opine catabolism gene)

Question 4

Describe the process of gene editing with Ti plasmid

Answer 4

Replacing genes in T-DNA with GOI.
when edited T-DNA enters plant cells, no tumour growth occurs anymore and makes the plant use the GOI.

Question 5

Describe the plant transformation process

Answer 5

Clone foreign DNA into agrobacterium Ti plasmid -> transform recombinant Ti plasmid into agrobacterium -> culture transformed bacteria

From there you can…
Wound plants and insert colonies (only would have transformed cells around wounded area)

OR grow callus with agrobacterium (with GOI) This case transformed plant cells are everywhere in the plant

Question 6

Applications of plant genetic engineering

Answer 6

Bt Gene: This bacteria produces toxins that kill insects and worms so this gene can be transformed into the cells and become pest resistant

Enhancing nutritional value (e.g. rice and fatty acids from plants)

Molecular farming (using plants to produce large quantities of pharmaceutical substances)