L3 & 4 - Hypothalamus Development

Question 1

Layout of CNS neurons

Answer 1

columns and layers

Question 2

Neuron layout in hypothalamus

Answer 2

neurons in clusters called nuclei

Question 3

Why is it hard to study hypothalamus

Answer 3

small, neurons intensely interlinked

Question 4

Effect of Shh deletion

Answer 4

hypothalamus does not develop

Question 5

Symptoms of Shh deletion

Answer 5

cyclopia, holoprosencephaly, no formation of ventral forebrain

Question 6

prechordal mesoderm function

Answer 6

expresses shh

Question 7

prechordal mesoderm location

Answer 7

axial mesoderm underlying anterior neural tube

Question 8

Shh in hypothalamus

Answer 8

induces fan shaped set of cells in above neural plate

Question 9

Technique of seeing shh effects

Answer 9

Ectopic transplant of pm expressing shh

Question 10

Examples of markers in hypothalamus

Answer 10

TFs - expressed in response to different conc of shh

Question 11

What happens to the arc patterns in the hypothalamus ?

Answer 11

rapidly obscured

Question 12

Specific examples of TF markers in hypothalamus

Answer 12

pax6
nkx2.2
foxa2

Question 13

What structure generates arc pattern in hypothalamus?

Answer 13

prechordal mesoderm

Question 14

PM mechanism of action

Answer 14

changes signalling properties

Question 15

PM signalling properties

Answer 15

first induces shh

then induces BMP & FGF10 expression in above neural cells

Question 16

Technique to detect FGF10

Answer 16

anti-sense in situ hybridisation

Question 17

Double in situ showed

Answer 17

population co-expresses shh, BMP7 & FGF & pathway components

Question 18

Why is co-expression of Shh, BMP & FGF unusual

Answer 18

TFs normally repress each others transcription

Question 19

Fate mapping of Shh, FGF10 & BMP7 positive cells showed

Answer 19

form hypothalamus

Question 20

Fate mapping technique

Answer 20

inject lipophilic dye DiL, double label expression of TF

Question 21

hypothalamic development model

Answer 21

sequential ansiotropic growth model

Question 22

What do FGF10, shh & BMP positive progenitors give rise to ?

Answer 22

anterior hypothalamic and posterior hypothalamic progenitors

Question 23

Movement of proliferating cells from FGF10, shh, BMP positive cells

Answer 23

anteriorly & posteriorly away - tangential movement

Question 24

what cells are retained?

Answer 24

central pool of FGF10+ positive progenitors

Question 25

Arc& VMN arose from ?

Answer 25

Shh responding progentiors

Question 26

TMN arose from ?

Answer 26

progenitors migrating in opposite direction ???? * CHECK

Question 27

FGF10+ population gives rise to ?

Answer 27

basal anterior & mammillary progenitors

Question 28

Progentiors patterned by shh -->

Answer 28

neurons that regulate sleep wake cycle

Question 29

FGF10+ hypothalamic cells

Answer 29

radial glial like cells - tanycytes

Question 30

beta tanycytes project to ?

Answer 30

median eminence

Question 31

alpha tanycytes

Answer 31

hypothalamic stem cells

Question 32

beta tanycyte function

Answer 32

allow metabolite & hormone entry into hypothalamus

Question 33

Tanycyte function - SC

Answer 33

neurogenesis - allostasis allow body to adapt to new optimums