Radial neuroepi cells stains
Nestin +ve
BLBP -ve
Radial glial cells stains
Nestin +ve
BLBP +ve
Role of radial glial cells
- undergoes neurogenesis
- acts as a guide for neurons migrating to the mantle zone
Dorsal Root vs Ventral Root
Dorsal = sensory
Ventral = motor
2 signalling centres at the D-V midline and their associated secretions
1) Roof plate (BMP) - dorsal
2) Floor plate (Shh) - ventral
V - D gradient morphogen
Shh
- partitions ventral basal plate into 6 classes of neurons
D - V gradient morphogen
BMP
What is expressed by pMN
Nkx6.1, Olig2
- NOT: Irx3, Nkx2.2
What is expressed by V3 interneuron progenitors
Nkx2.2
- NOT: Pax6, Olig2
Function of Nx6.1
turns on Olig2 expression
Function of Olig 2
Induces motor neuron differentiation
- activates Hb9, lsl1/2
Name motor neuron differentiators
Hb9, lsl1/2
2 progenitor regions of dorsal alar plate
1) most dorsal - 3 domains - Class A dl1-3 INs
2) intermediate - 6 domains - Class B dl4-6 INs
Where are BMPs secreted from
Roof plate
- bind to BMPRs
- recruitment of Smad 1/5
in situ hybridisation function
measure mRNA
BMP/Wnt signalling dependant neuron differentiation
Class A
BMP/Wnt signalling independant neuron differentiation
Class B
What genes does BMP/Wnt signalling activate
- Olig3
- Atoh1 (dl1)
- Neurog1/2 (dl2)
- Ascl1 (dl3)
“O, Ana!”
Cell specific determinants of Class A progenitors
1) Atoh1
2) Neurog 1/2
3) Ascl1
What progenitor cells express Olig3
All Class A progenitor cells
Olig3
- represses Lbx1
- specifies dl1-3 interneurons
