Exam 1: Lecture 2

Question 1

neural progenitor expansion and neurogenesis occurs in

Answer 1

ventricular zone

Question 2

After mitosis daughter cells become ___ post mitotic

Answer 2

fixed

Question 3

During neuroepithelial cell division, ____ allows cells to divide unrestricted while maintaining dense packing

Answer 3

interkinetic nuclear migration

Question 4

Neuroepithelial (NE) cells:

Division type
progeny

Answer 4

Symmetric

2x NE

Question 5

Radial Glial progenitors (RG):

division type
progeny

Answer 5

Asymmetric

neurons, BPs

Question 6

Basal Progenitors (BP):

division type
progeny

Answer 6

symmetric

two neurons

Question 7

The length of cell cycle increases during embryogenesis mainly due to lengthening of ___ phase.

Answer 7

G1

reflects regulation of S entry

longer G1= increased chance of making neuron

Question 8

Symmetric Division

Answer 8

neuroepithelial/radial glia

VERTICAL CLEAVAGE
bigger neuroepithelium (horizontal) 

tangential expansion

Question 9

if cleavage plane horizontal or tilted

Answer 9

asymmetric division

Question 10

____ proteins control cleavage plane

Answer 10

SNARE

Question 11

Symmetric division needs ___ interactions of SNARE, asymmetric needs ____

Answer 11

heterophilic (basolateral apical)

homophilic (basolateral x2 )

Question 12

What if apical t-SNARE not present?

Answer 12

only 1 daughter cell is neuron

Question 13

What is the molecular marker selectively expressed in essentially all neuroepithelial cells about to undergo neurogenic division?

Answer 13

Tis21

Question 14

Humans have more (basal/apical) progenitors

Answer 14

basal

more diverse

Question 15

Symmetric division (NP SELF-RENEWAL)
increases \_\_\_\_ progenitors

Answer 15

radial glia

Question 16

Asymmetric (NEUROGENIC DIVSION)

produces

Answer 16

radial glia

column of neurons destined to all layer

Question 17

Symmetric division of INTERMEDIATE progenitors in SVZ produce

Answer 17

Radial glia

produce multiple columns of neurons (or radial column) destined to all layers of cortex

Question 18

Size of ___ (with INTERMEDIATE PROGENITORS) predicts the location of gyra and sulci in human cortex.

Answer 18

SVZ

Question 19

Radial unit hypothesis

Answer 19

cortex develops as array of interacting cortical columns or radial units, each of which originates from progenitor in VZ

Question 20

Protomap

Answer 20

primordial identity of each function cortex area is encoded with cortical progenitors prior to formation of cortical layers.

Question 21

Mutations in genes regulating interkinetic nuclear migration (INM) produce

Answer 21

deficits in NP proliferation (microcephaly)

Question 22

NP proliferation is regulated by the length of the ___ ___

Answer 22

cell cycle

Question 23

mutations in genes that regulate ______ (Pax6/filamin) OR _____ (Rac1, cyclin D2, Numb stuff) affect NP proliferation and final position of neurons

Answer 23

cell cycle length

cell cycle exit

Question 24

Longer NP proliferations creates new opportunities for ____

Answer 24

regulation

regulated by factors secreted from afferent connections

Question 25

Polymicrogyria

Answer 25

regions of complex and excessive number of cortical convolutions with miniature gyri fused and superimposed together GPR56 16q130 bilateral Enviornment: intra utero ischemia, prenatal infection, toxoplasmosis, cytomegalovirus Symptoms: epilspy, delay, cerebral palsy, ID, dyslexia

Question 26

migrating cells- describe them

Answer 26

elongated soma, | trailing process which will be axon

Question 27

Excitatory neurons are generated in an ____ fashion

Answer 27

inside-out

Question 28

____ are generated in non-cortical locations for the most part

Answer 28

interneurons

Question 29

How do we track location of progenitors at different points in development?

Answer 29

3H-thymidine BrdU during S phase right before division Can use prospective and retrospective lineage tracing

Question 30

Genetic recombination lineage tracing

Answer 30

Fate mapping with CRE Green: Wnt1-CRE: recombination occurs Red: no cre, no recombination. stop tomato

Question 31

Sequential competence:

Answer 31

A --> B --> C | things only from certain things

Question 32

Independent | multipotential lineage vs. unipotential lineages

Answer 32

multi: red vs. blue ' uni: red vs. blue then light vs. dark

Question 33

Nest multpotential lineages

Answer 33

random stuff?

Question 34

The sequential competence state model states that progenitors potential becomes progressively ____ over time

Answer 34

Restricted Layers 6 --> 123 but 123 --> 123

Question 35

Tangential migration: interneurons migrate like this brings neurons orginated ___ to structure and gives rise to structures of mixed origin

Answer 35

far away

Question 36

Do radial and tangential migration occur same time?

Answer 36

Yes

Question 37

Radial migration relies on

Answer 37

short range and cell adhesion signals

Question 38

Tangential migration

Answer 38

relies on all types of signals: short range, long range, diffusible, cell-cell interactions

Question 39

In caudal neural tube ___ migration is more predominant

Answer 39

radial

Question 40

___ migration = development of cerebellum. External granule cell layer of the cerebellum comes from rhombic lip at the lateral border of the 4th ventricle. This gives rise to all granule cells.

Answer 40

Tangential

Question 41

In thalamus, what plot twist

Answer 41

outside born first, inside last inside= correspond to nuclei close to 3rd ventricle outside= nuclei close to border of thalamus

Question 42

Migration disorder: Periventricular hetertopia/filamin1 mutation

Answer 42

neurons don't migration out of VZ

Question 43

When ongoing migration fails: Lissencephaly (LIS1 and DCX)

Answer 43

proper inside out pattern but | imprecise manner

Question 44

When ongoing migration fails: Double cortex

Answer 44

mutation in DCX (x linked gene) Due to x-inactivation, one neuron population with mutation doesn't migrate correctly and stays below cortical plate

Question 45

If final stage of migration fails (reeler mouse)

Answer 45

rough inversion of inside out pattern of cortical migration excess of neurons normally cell-sparse marginal zone. Dab1 is involved

Question 46

Cdk5 and p35: inverted cortical plate, but it's special

Answer 46

leave marginal zone intact don't disrupt accurarcy with which neurons of similar type laminate

Question 47

____ mutant: subplate in middle of cortical plate

Answer 47

Cdk5

Question 48

___ mutant: subplate is beneth cortical plate

Answer 48

p35

Question 49

What is the most common symptom of migration disorder

Answer 49

seizure