L5 GOK

Question 1

radial gial cells generate ?

Answer 1

neurons and last divisions into glia

Question 2

Apical surface is the sit of ?

Answer 2

stem proliferation and division

Question 3

asymmetric cell division requires proteins where ?

Answer 3

a number at the apical and basal poles

Question 4

where are the apical / basal surfaces ?

Answer 4

The apical surface is near the ventricle while the basal surface isnt

Question 5

what complex of proteins is at the apical pole / ventricular surface ?

Answer 5

Par complex

Question 6

When the par complex is recruited to the apical pole it forms ?
and what does it do ?

Answer 6

apical complex - contains par , inscuteable and pins

it dictates mitotic spindle orientation

Question 7

whats a mitotic spindle ?

Answer 7

strings that pull chromosomes apart into two daughter cells during mitosis
made of microtubules

Question 8

what is the orientation of these spindles in both types of division ?

Answer 8

symmetric - horizontal

asymmetric - vertical

Question 9

during asymmetric cell division which cell gets the apical complex ?

Answer 9

the parent cell

Question 10

what do proteins in the apical complex activate in neuroblasts ?

Answer 10

delta-notch signalling

represses proneural genes = maintains stem cell state

Question 11

in asymmetric cell division which cell receives the basal complex ?

Answer 11

the daughter cell

the apical complex causes the basal complex to move to the basal pole

Question 12

whats basal comples consist of ?

Answer 12

miranda
numb/ partner of numb / prospero - pink dots
Ccnd2 Trem32

Question 13

what do the basal complex TF’s do ?

Answer 13

turn on genes for neuronal diff.,
switch off genes for proliferation, and
inhibit Notch signalling pathway

=De-repress proneural genes = Neuronal differentiation

Question 14

how cell fate determinants distributed in humans, mice, zebrafish ?

Answer 14

humans - equally (symmetric)
mice & zebrafish - unequally (asymmetric)

reason unknown

Question 15

whats happens in vertebrate neurogensis in order to increase the stem cell pool ?
whats the next step ?

Answer 15

neuroepethelail cells (NEC) (nestin marker)undergo symmetric cell divisions

NEC convert to radial glial cells (which express marker BLBP + nestin)

Question 16

once the stem cell pool has been increased and radial glial cells RGC are present how are neurons formed ?

Answer 16

asymmetric divisons of RGC = RGC + neuron

Question 17

cells that are nestin positive but BLBP neg are ?

Answer 17

neuroepethelial cells

Question 18

RGC cells become elongated due to the ?

Answer 18

thick mantle layer

Question 19

RGC hoses bipolar processes attach to the basal and apical surfaces act as what for migrating neurons ?

Answer 19

guide

Question 20

explain time line from NEC to neuron …

Answer 20

NEC -> RGC -> intermediate progentitor cell ->immature neuron -> mature neuron

mature neurons -> glutaminergic/GABAergic/DAergic/5HTergic/chloinergic

Question 21

timeline fro NEC to glia ….

Answer 21

NEC -> RGC -> oligodendrocyte precursor cell -> oligodendrocyte
NEC-> RGC-> astrocyte

Question 22

how do intermediate progenitors effect neuron output from RGCs?

Answer 22

they double it

IP = two neurons

Question 23

whats the delta ligand for notch ?

Answer 23

DLL4

Question 24

what enzyme cleaves notch intracellular domain ?

Answer 24

g-secretase

Question 25

what does delta-notch sig trigger transcription of ?

Answer 25

Hes genes

Question 26

what do hes genes repress ?

Answer 26

bHLH proneural genes - neurogenin and asc 1

keeps cells in proliferate state

Question 27

notch lignads delta and E3 ubq ligase MINDBOMB are expressed in neurons and IP when ?

Answer 27

after asymmetric cell division

Question 28

wnt binds to which receptors ?

Answer 28

frizzled and co receptors - LRP 5/6

Question 29

wnt binding causes?

Answer 29

stabilsation of b catenin translocates to the nucleus where it
mediates gene transcription through LEF/TCF transcription factor activity

Question 30

B catenin is ?

Answer 30

An intracellular protein involved in development of whole body systems in early development and specific cell types later on

Question 31

Early in neurogenesis  Wnt signalling promotes ?

Answer 31

symmetric cell division

Question 32

• Later in neurogenesis wnt signalling promotes

Answer 32

neuronal differentiation through upregulation

of a transcription factor known as N-myc

Question 33

what receptor does shh bind to ? and what does this lead t o ?

Answer 33

patched receptor

accumulation of smoothened -> allows processing of gli TFs by blocking SUFU -> mediates gene transcription

Question 34

what is smoothened ?

Answer 34

a class of frizzled g protein coupled receptor

Question 35

what happens to gli TFs without shh ?

Answer 35

theyre processed into repressive forms

Question 36

what is shh signalling nb for ?

Answer 36

dorsoventral patterening in vertebrate central nervous system

Question 37

Early in neurogenesis shh sig promotes ?

Answer 37

symmetric proliferation of

RGCs through transcription of the Notch transcription factor Hes1

Question 38

late neurogenesis what happens to shh signalling ?

Answer 38

decreases and gli repressor increases = neuronal diffrin

Question 39

oligodendrocyte fate is determined by which TFs?

Answer 39

Olig1/2

Question 40

shh activates oligo1/2 in the ventral sc to ?

BMP inhibits oligo1/2 in dorsal sc to?

Answer 40

induce oligod formation and inhibit astrocytes

inhibit olgiod and promote astroctye formation

Question 41

which morphogens act antagonistically to determine glial fate ?

Answer 41

shh and BMPs

Question 42

notch pathway stimulates gliogenesis by?

loss of notch =?

Answer 42

repressing proneural BHLH TF

more neurons at the expense of glia