13. Neural Tube Formation

Question 1

What occurs simultaneously with gastrulation?

Answer 1

Neural tube formation

This process is crucial for the development of the central nervous system.

Question 2

What is the role of the organizer (dorsal mesoderm) in neural plate induction?

Answer 2

Dorsalizes the ectoderm to induce neural plate

Question 3

Name three organizer genes involved in neural induction.

Answer 3

• Noggin
• Chordin
• Follistatin

Question 4

What is the function of organizer genes?

Answer 4

Act as ligands targeting the BMP signaling pathway and inhibit BMP signaling

Question 5

What does BMP stand for?

Answer 5

Bone Morphogenetic Protein

Question 6

What is the role of BMP in embryonic development?

Answer 6

Promotes epidermis formation

Question 7

What happens when BMP signaling is inhibited?

Answer 7

Leads to neural plate induction

Question 8

What pathway does TGF-β signaling belong to?

Answer 8

TGF-β family signaling pathway

Question 9

What is the consequence of receptor binding in TGF-β signaling?

Answer 9

Causes phosphorylation and activates Smad proteins

Question 10

What is Sox2 known for?

Answer 10

Important marker for neural plate induction and key pluripotency factor

Question 11

What do Morpholino experiments show regarding organizer genes?

Answer 11

Downregulating them prevents neural plate formation

Question 12

What is the effect of downregulating BMP genes?

Answer 12

Causes entire embryo to become neural tissue

Question 13

List the primary steps in neurulation.

Answer 13

• Neural Plate Thickening and Elongation
• Neural Plate Folding
• Neural Fold Convergence
• Neural Tube Closure

Question 14

What initiates neural plate thickening?

Answer 14

Organizer proteins like Noggin

Question 15

What mediates neural plate folding?

Answer 15

Formation of hinge points and apical constriction of cells

Question 16

What are the Medial Hinge Point (MHP) and its characteristics?

Answer 16

• Forms first
• Located above notochord
• Driven by Sonic Hedgehog

Question 17

What is the function of Sonic Hedgehog in neural tube formation?

Answer 17

Promotes medial hinge point formation and inhibits Noggin

Question 18

What is the role of Noggin in hinge point formation?

Answer 18

Promotes dorsolateral hinge point formation and inhibits BMP

Question 19

What is the significance of morphogen gradients in neural tube formation?

Answer 19

Create gradients along the dorsal-ventral axis

Question 20

What are the three key morphogens involved in neural tube formation?

Answer 20

• Sonic Hedgehog (Shh)
• Noggin
• BMP

Question 21

What is the role of differential cadherin expression in neural tube closure?

Answer 21

Drives separation of neural tube from epidermis

Question 22

What clinical disorders are associated with neural tube closure defects?

Answer 22

Disorders like spina bifida

Question 23

What happens when neural tube closure fails?

Answer 23

Exposes neural tissue to amniotic fluid, leading to cell death

Question 24

What are the three primary vesicles formed after neural tube closure?

Answer 24

• Forebrain (prosencephalon)
• Midbrain (mesencephalon)
• Hindbrain (rhombencephalon)

Question 25

Name some model organisms used to study neural tube formation.

Answer 25

* Frog (Xenopus) * Mouse * Chick * Tunicate

Question 26

What provides detailed insights into neural tube formation?

Answer 26

High-resolution imaging and mathematical modeling