Lecture 6-Crown gall tumour

Question 1

Agrobacterium tumefasciens

Answer 1

common soil bacterium, sends TDNA into wounds of plant that is tumor inducing. borne from aerosols, rainsplash

Question 2

acetosyringone

Answer 2

compound released by plants

Question 3

VirA/G sensor proteins

Answer 3

detects plant compounds, triggers signal transduction in bacterium, cause trascription of Vir genes in Ti plasmid

Question 4

Plasmid

Answer 4

small independently replicating pieces of DNA

Question 5

Vir genes

Answer 5

produce transcripts that produce vir proteins

Question 6

VirB

Answer 6

build pilus(entry point) to breach plant cell. help move other protein complexes through pilus into plantcell

Question 7

Vir D1/D2 protein complex

Answer 7

cuts out some DNA from ti-plasmid (called T-DNA) (transfer)

Question 8

Complex protein

Answer 8

2 or more linked proteins

Question 9

Plasmid DNA

Answer 9

single strand, bound 5’ to VirD2, also a complex-nucleic acid (TDNA) and protein (VirD2) looks like telephone cord

Question 10

VirE2

Answer 10

protein that coats plasmid DNA complex
acts as: 1. protection from nucleases
2. provision of signal, has NLS recognized by protein (importin alpha) at nucleopore

Question 11

TDNA once in nucleus

Answer 11

separates from other proteins in complex, bacterial protein splices DNA into plant chromosomes

Question 12

illegitimate recombination

Answer 12

splicing of TNDA into plant chromosomes

Question 13

Opines

Answer 13

produced by enslaved plant cell, useless to plants, produced/exported to feed bacterium

Question 14

Genetic colonization

Answer 14

plant parasitized by genetic parasites

Question 15

Bioengineering of insulin

Answer 15

1982. human insulin gene put in E. coli (bacterium), raised in fermentors to produce massive amounts of insulin

Question 16

academic genes

Answer 16

used to study physiological responses

eg photosynth, terpene synth

Question 17

industrial genes

Answer 17

used to confer insect resistance and herbicide resistance

Question 18

How to create a transformed plant

Answer 18

sterile leaf
1punch hole in leaf
2.dip disc in solution of A. tumefasciens that has gene of interest in plasmid
3. put disc in tissue culture to regenerate whole plant
4. put plants into greenhouse to breed and test for new character then bulked to produce commercial seed

Question 19

single gene transfer

Answer 19

most powerful crop improvement tool ever invented

Question 20

Amount of genetically transformed crops in world

Answer 20

125 million acres

Question 21

Domain

Answer 21

porrtion of plant that is highly well-connected by symplast

Question 22

Plasmodesmata size exclusion limits

Answer 22

do not allow molecules that exceed 1000kDa

Question 23

3 states of Plasmodesmata

Answer 23

closed,open, dilated

Question 24

Dilated plasmodesmata size limit

Answer 24

27kDa

eg Green fluorescent Protein

Question 25

Action potential in venus fly trap

Answer 25

in hair cell,stored Ca is released into cytoplasm, increased [ ] causes membrane depolarization. change in charge spreads from cell to cell until trap closes. transmitted via plasmodesmata of sensory hairs

Question 26

Aldrovandra vesiculosa. waterwheel plant

Answer 26

snap trap like venus fly trap, shuts in 0.02s. one of fastest responses in entire world