Neurogenesis and Migration Flashcards

1
Q

Lissencephaly means ___________.

A

smooth brain (i.e., a brain without sulci)

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

Post-mitotic cells must ___________ a radial glia to __________. Any defect in the genes that encode for this can result in lissencephaly.

A

adhere to; migrate to the more superficial layers of the cortex

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

Reelin is involved in ___________.

A

migration in the cortex and the cerebellum

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

What cells secrete reelin?

A

Cajal-Retzius cells

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

__________ have a more severe phenotype of lissencephaly / double-cortex syndrome.

A

Males (because it is X-linked)

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

List three genes that, if disrupted, can lead to defects in cortical migration.

A

Reelin and LCH (getting off of the radial glia)
Filamin (getting on)
DCX and Lis1 (staying on the radial glia)

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

What is LCH?

A

Lissencephaly with cerebellar hypoplasia; a protein involved in getting off of the radial glia

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

What area of the nervous system has the opposite pattern of cortical migration (that is, opposite to the inside-out pattern)?

A

The retina; in the retina, the neurons migrate outside-in (with the distal-most cells migrating first)

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

What are neurotrophins?

A

Proteins that stimulate the growth of neurons – such as nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), NT-3, glia-derived neurotrophic factor (GDNF), and NT-4

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

To what type of receptors do neurotrophins bind?

A

Tropomyosin-related kinase (Trk)

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

Almost ________ percent of the Cajal-Retzius cells die during development.

A

100

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

Growth cones have ________ with a dense population of ___________.

A

filopodia; receptors

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

CAMs are _________. They work independently of calcium.

A

cell-adhesion molecules

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

Cytokines directing axonal migration can be repulsive or attractive depending on ______________.

A

the receptor it binds

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

In patients with a defective filamin protein, _________ cells accumulate in the ventricular zone.

A

differentiated (because the filamin protein helps differentiated cells migrate outward)

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

Mutations in LIS1 will produce ___________.

A

lissencephaly with epilepsy and mental retardation

17
Q

Neurons born at the same time tend to ____________.

A

end up in the same layer

18
Q

Cell death in most neurodegenerative diseases occurs by _____________.

19
Q

What is the neurotrophic factor hypothesis?

A

The idea that neuron targets produce limited amounts of neurotrophic factors so that only the closest neuron will make a connection

20
Q

Netrins can be _______ or __________.

A

attractive; repulsive

21
Q

Semaphorins are always ____________.

22
Q

Cadherins, CAMs, laminin, and proteoglycans are usually __________ signals.

A

attractive

23
Q

CNS oligodendrocytes express __________, thought to play a role in preventing axon growth.

24
Q

What neurogenic pattern is typical of autism spectrum disorders?

A

A brain small at birth followed by an abnormally high rate of growth resulting in disproportionately high content of white matter

25
In the CNS, myelination is first observed at the end of the ___________.
first trimester
26
How are GABA channels different in embryonic development?
The E(Cl) is less negative, so GABA channels actually depolarize the cell membrane during development!