CNS Neuroembryology Flashcards
the CNS develops from which embryonic layer?
ectoderm
how long after fertilisation do the neural folds appear?
3 weeks
how long after fertilisation do the neuropores close?
4 weeks
what is the function of reelin?
secreted by CNS cells to promote migration of new neurons
what proteins are in the apical side of neuroprogenitor cells?
Par complex (Par3/6, aPKC)
actin
n-cadherin
what is in the basal side of neuroprogenitor cells?
nucleus
how do early neuroprogenitor cells proliferate and why is this special?
symmetrical proliferation
daughter cells inherit equal amounts of apical proteins
how does neuroprogenitor proliferation change and why is this important?
asymmetrical proiferation
1 daughter cell inherits all the apical proteins (apical sister)
1 daughter cell remains to maintain progenitor pool (basal sister)
what is the process by which the apical polarity is lost and why is this important?
apical abscission
loss of primary cilium, loss of SHH signalling, exits cell cycle, migrates to destination
what condition is caused by errors in the process of apical abscission?
periventricular hypertrophy
what condition is caused by errors in the primary cilium and SHH signalling?
Joubert syndrome (autosomal recessive, brainstem/cerebellum underdevelopment)
what proteins are important for the axis development of the brain?
FGF
SHH
where are high levels of FGF found in the developing brain?
at the forebrain-hindbrain boundary
where are high levels of SHH found in the developing brain?
at the ventral forebrain
which protein is important for hemisphere separation?
SHH
what are the flexures of the developing brain?
cephalic
pontine
cervical
when does the pontine flexure appear?
7 weeks
what are the 3 primary brain areas seen at 3 weeks?
prosencephalon
mesencephalon
rhombencephalon
what does the prosencephalon develop into at 7 weeks?
telencephalon
diencephalon
what does the rhombencephalon develop into at 7 weeks?
metencephalon
myelencephalon
what does the medulla develop from?
myelencephalon
what does the pons and cerebellum develop from?
metencephalon
which proteins generate the dorsal-ventral axis of an embryo?
BMP (dorsal)
SHH (ventral)
which proteins generate the rostral-caudal axis of an embryo?
retinoic acid (rostral) FGF (caudal)
