Lecture 30: Neural Crest

Question 1

What signaling molecules are involved in induction of neural crest tissue from non-neural ectoderm?

Answer 1

BMPs, Wnts

Question 2

What signaling molecule is involved in induction of neural crest tissue from mesoderm?

Answer 2

FGF-8

Question 3

What substrate is preferable for migration of neural crest cells?

Answer 3

Basal lamina

Question 4

List early, later, and late migratory neural crest cells in order from most to least potential for differentiation

Answer 4

Early, later, late

Question 5

What was the result of an experiment in which thoracic neural crest cells were transplanted to head region and vice versa?

Answer 5

Sympathetic and parasympathetic character of neurons were reversed

Question 6

What was the result of an experiment in which dye-injected neural crest cells were grown in vivo?

Answer 6

More thatn 50% of the progeny gave rise to 2-4 phenotypes

Question 7

What was the result of an experiment in which rat neural crest cells in vitro were exposed to glial growth factor?

Answer 7

Cells developed into Schwann cells; glial growth factor suppressed neuronal differentiation

Question 8

Name the 5 neural crest cell divisions

Answer 8

Trunk, Cranial, Circumpharyngeal, Cardiac, Vagal

Question 9

Name the 3 migration pathways of trunk neural crest

Answer 9

Sympathoadrenal, ventrolateral, dorsolateral

Question 10

Name the cells that originate from the sympathoadrenal path

Answer 10

Adrenal chromaffin cells, adrenergic sympathetic neurons, cholinergic sympathetic neurons

Question 11

Name the cells that originate from the ventrolateral path

Answer 11

Dorsal root ganglia (sensory), Schwann cells

Question 12

Name the cells that originate from the dorsolateral path

Answer 12

Melanocytes

Question 13

What is the role of Dickopf-1 regarding cranial neural crest?

Answer 13

Inhibits neural crest cells from arising anterior to diencephalon

Question 14

Which neural crest cells express Hox genes?

Answer 14

Cells from R4 and posteriorly

Question 15

What would be the result of Hox gene expression in pharyngeal arch 1?

Answer 15

A jaw would fail to develop

Question 16

What is the fate of neural crest cells from somites 1-3?

Answer 16

Pass into pharyngeal archest 4-6 or form cardiac crest

Question 17

What is the fate of neural crest cells from somites 1-7?

Answer 17

Form vagal crest, parasympathetic innervation for digestive tract

Question 18

What is the role of Slit-2/Robo in neural crest?

Answer 18

Expression of Slit-2 allows neural crest to enter gut wall; Robo expression avoids gut wall

Question 19

Waardenburg’s syndrome

Answer 19

Pax3 mutation leading to pigmentation defects (such as white forelocks of hair)

Question 20

CHARGE

Answer 20

Coloboma, Heart disease, Atresia of nose, Retardation, Genital hypoplasia (males), anomalies of Ear

Question 21

DiGeorge syndrome

Answer 21

Deletion of chromosome 22; hypoplasia of thymus, parathyroid, thyroid

Question 22

Neurofibromas

Answer 22

Tumors of neural crest region

Question 23

Which of these cell and tissue types arises from cranial, but not trunk, neural crest cells?

A. Sensory ganglia
B. Adrenal medulla
C. Melanocytes
D. Schwann cells
E. None of the above

Answer 23

E. None of the above

Question 24

Which molecule is a poor substrate for migrating neural crest cells?

A. Laminin
B. Chondroitin sulfate
C. Fibronectin
D. Type IV collagen
E. Hyaluronic acid

Answer 24

B. Chondroitin sulfate

Question 25

Neural crest cells arise from the: ``` A. Somite B. Dorsal non-neural ectoderm C. Neural tube D. Splanchnic mesoderm E. Yolk sac ```

Answer 25

C. Neural tube

Question 26

A 6-month-old infant exhibits multiple congenital defects, including a cleft palate, deafness, ocular hypertelorism, and a white forelock but otherwise dark hair on his head. The probable diagnosis is: ``` A. CHARGE association B. von Recklinghausen's disease C. Hirschprung's disease D. Waardenburg's syndrome E. None of the above ```

Answer 26

D. Waardenburg's syndrome

Question 27

What molecule is involved in the migration of neural crest cells from the neural tube? ``` A. Snail B. BMP-2 C. Mash-1 D. Norepinephrine E. Glial growth factor ```

Answer 27

A. Snail

Question 28

Which is not a derivative of the neural crest? ``` A. Sensory neurons B. Motor neurons C. Schwann cells D. Adrenal medulla E. Dental papilla ```

Answer 28

B. Motor neurons

Question 29

What maintains the competence of neural crest cells to differentiate into autonomic neurons? ``` A. Shh B. Ach C. Mash-1 D. Glial growth factor E. TGF-B ```

Answer 29

C. Mash-1

Question 30

If trunk neural crest cells are transplanted into the cranial region, they can form all of the following types of cells except: ``` A. Pigment cells B. Schwann cells C. Sensory neurons D. Cartilage E. Autonomic neurons ```

Answer 30

D. Cartilage