Placzek review

Question 1

what does formation and wiring of the NS involve?

Answer 1

the spatial and temporal produciton of neuronal and glial subtypes which are distinct

Question 2

what does the NS arise from?

Answer 2

the NT

Question 3

what is the neural tube recognised as?

Answer 3

thickened single cell thick neuroepithelium that forms over the midline of the embryo

Question 4

what does Shh mediate in NT?

Answer 4

mediates NTventral patterning

- secreted factor which mediates induction of multiple distinct ventral cell types along rostro-causal axis

Question 5

what happens in Shh KO mice?

Answer 5

• loss of ventral cell types (motor neurons)
• holoprosencephaly
• no hypthalamus formation
• importance of Shh in neural tube

Question 6

how is nkx2.1 expression induced?

Answer 6

-six3 interacts with shh to induce nkx2.1 expression

Question 7

how does Shh act as a guidance cue

Answer 7

is in floorplate
- can help attract C axons to the floorplate and then repel them anteriorly once they have crossed (Wnt4 attracts anteriorly)

Question 8

how is shh switch from attractive t repulsive mediated?

Answer 8

by par like homolog

14-3-3 (inhibit pka activity)