L18

Question 1

Cell lineage determination

Answer 1

Lateral inhibition -> neuroblast delamination -> GMC + second order neuroblast -> neurons

Question 2

Timing

Answer 2

Neuronal cell fate established by timing of cell division; the combination of TFs a neuroblast is competent with depends on the number of cell divisions

Question 3

Asymmetric localisation of mRNA/protein in GMC

Answer 3

One cell can divide to produce two distinct cell types

Question 4

Position

Answer 4

I.e. distance from relevant radial glia

Question 5

What affects neuronal identity?

Answer 5

Timing, localisation of mRNA/proteins, position

Question 6

Neuronal diversity created by…

Answer 6

…chemical gradients; decreasing SHH away from midline, FP->MN->V2->V1 (same for ventral from RP)

Question 7

[fly] Hox gene mutations…

Answer 7

…bx, pbx- bithorax; antp (wt=Antp) (+pb-)- antennapedia

Question 8

Hox genes pattern the brain and SC…

Answer 8

Hoxb1 mt causes trigeminal like MNs in place of facial MNs

Question 9

Individual Ns specified through ion channel gene expression, NT type, R expression…

Answer 9

…combinatorial codes of TFs(islet, Lim3, Hb9, Eve in fly MN); in flies, only some MNs express shaker K+ channel: TF codes specific ion channel expression etc

Question 10

Gene batteries…

Answer 10

…all necessary components for X transmitter system; transmitter switching can occur