Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Developmental Neuroscience > Genetic Tools to Study Neural Circuits > Flashcards

Genetic Tools to Study Neural Circuits Flashcards

1
Q

Disadvantage of traditional transgenic animals

A

viability - deletion may be fatal
non selective = not site specific
present from birth - not good for developmental adaption

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Conditional gene targetting

A

allows inactivation of a gene restricted to an organ and/or developmental stage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

how many mouse strains needed for cre loxp

A

2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

how many bp is loxP?

A

34

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

how can cre-lox P result in inversion?

A

loxP sites face eachother and flank gene

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

cre lox mediated activation

A

lox P sites flank poly A which prevent transcription - delete then gene left active

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

3 parts of viral vector

A

virus particle
envelope
capsid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what does envelope determine?

A

tropism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what does capsid do?

A

enclose genetic material

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

3 types of virus used

A

adenovirus - high immunogenicity, dsDNA
retrovirus/lentivirus
AAV - very low immunogenicity - ssdna

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

virus construct creloxp

A

gene inverted beside lox p sites

specific areas with cre will be switched on to become active

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what can enhance cre-lox usefulness?

A

reporter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

examples of previous reporters and problems?

A

luciferase, beta galactosidase

require exogenous substrates - no good for living tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

reporter

A

labels cell - can see cells infected with virus

now use genetically encoded fluorescent proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

GFP

A

discovere 1960s in jellyfish

238 amino acids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

concentration of calcium at rest

A

50-100nM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what does calcium activity correlate with?

A

electrical activity

firing frequency and fluorescence - direct correlation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

chemical calcium indicator

A

fura-2

19
Q

genetically encoded calcium indicators

A

GCamp in GFP cells - change fluorescence depending on calcium around indicator
GFP, calcmodulin and M13

20
Q

single cell loading of calcium indicator

A

sharp electrode, whole cell patch clamp or single cell electroporation

21
Q

in vivo photometry

A

mouse - GCaMP expressing cells in part of brain
implant small optic fibre - light source and collect emitted light
photoreceiver output voltage = average light intensity
light intensity = cell activity eg can get animal to run on treadmill

22
Q

In vivo calcium imaging

A

GCamp in group of cells
put in lens - see when particular cell active or not
graded refractive index lens

23
Q

tracers

A

compounds transported along axons away from injection site

24
Q

what is neural tracing often combined with?

A

immunohistochemistry or insitu hybridisation

25
Q

example of anterograde tracers

A

rhodamine isothiocyanate

[3H] amino acids

26
Q

explain anterograde tracers

A

from brain area A to B and C

27
Q

example of retrograde tracers

A

latex spheres
fast blue
fluorogold

28
Q

explain retrograde tracers

A

B receives inputs from A and C so B transports it back to A and C

29
Q

polysynaptic tracer

A

pseudorabies
taken up by cell but moves back to connected cells
hard to tell if connected directly or neurones inbetween

30
Q

monosynpatic tracer

A

AAV
modified rabies virus
taken up by cell - direct connection

31
Q

how to find what cells are directly connected

A 
cre in subset of neurons 
inject virus into 2 brain areas
expression - green
2 days later inject with rabies virus, red fluorescent 
cannot jump synapses
32
Q

Channel rhodopsin 2

A

light sensitive cation channel

naturally occur in unicellular green algae

33
Q

3 other opsins

A

bacteriorhodopsin
halorhodopsin
channelrhodopsin

34
Q

in vivo optogenetics

A

chr2 in some cells - optic fibre and light source

35
Q

ex vivo optogenetics

A

inject virus - chr2 in gabaergic neurons with YFP
label other par of brain with RFP
light stimulus affect other cells
record electrophysiology

36
Q

DREADDS

A

designer receptors exclusively activated by designer drugs

get excitable and inhibitory ones

37
Q

what are DREADDs mutated forms of?

A

human muscarinic receptors

hm4d

38
Q

what activates DREADDS?

A

inert ligand clozapine-N-oxide (CNO)

not Ach

39
Q

what binds DREADDS?

A

metabolite clozapine - not really inert

40
Q

DREADD expressed in 2 parts of hypothalamus - LHA and PVH

A

LHA - increase food intake with cno

PVH decreased food intake with cno

41
Q

what toxin used in toxin receptor mediated cell KO?

A

diptheria toxin

42
Q

diptheria toxin

A

exotoxin made by bacterium corynebacterium diptheriae

43
Q

mice and rats and DT

A

resistant

conditional cell ablation to mice expressing human DTR in specific cell population

Developmental Neuroscience (10 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions