L9 HS

Question 1

what signals mediate neural migration

Answer 1

Extracellular cues
Intracellular signalling pathways
Rearrangement of cytoskeletal components

Question 2

Migrating promoting signals ?

Answer 2

Rho family of GTPases; Rac, Cdc42, RhoA

Question 3

Attractive cues

Answer 3

Netrin1 via specific cell surface receptors

Question 4

Replusive cues

Answer 4

Slit 1/2

Question 5

Tangential migration of cortical GABA interneurons from where to where ?

Answer 5

MGE - neocortex

Question 6

GABA CIN migratory signals ?

Answer 6

BDNF
GDNF - glial dervied
NT4 - neurotrophin 4
HGF - hepacyte growth factor

Question 7

What repels GABA CIN away from striatum

and LGE ?

Answer 7

Striatum -Sema3A/F

LGE - slit 1/2

Question 8

what attracts GABA CIN to neocortex?

Answer 8

EMX1, EMX2 (homeobox proteins)

and NRG-Ig

Question 9

Tangential migration of olfactory interneurons from where to where ?

Answer 9

LGE - Olfactory bylb

Question 10

migratory signals for OIN

Answer 10

Lamin substrate alpha5
gamma1,
ECM HMW proteins

Question 11

Attractive signals OIN ?

Replusive signals OIN?

Answer 11

Netrin 1

Slit 1/2

Question 12

Tangential migration of GnRH neurons also called ?

Answer 12

axophilic
migration; migrating along anterior-posterior
axis of the body using exisiting axon tracts
(nose-> forebrain -> hypothalamus)

Question 13

what axons do the GnRH neurons migrate on ?

Answer 13

migration of GnRH neurons along the central

processes of vomeronasal axons

Question 14

GnRH need which for adhesion to axons?

Attract to POA and hypothalamus by ?

Answer 14

PSA-N-CAM and TAG1

attraction by netrin1

Question 15

Multipolar migration ?

Answer 15

can occur on its own or with other migration types
slower

neuronal movement mediated by Actin and Microtubule binding molecules as well as adhesion proteins

Question 16

Filamen A (actin) role in multipolar migration?

Answer 16

changes cells from bipolar to multipolar and facilitates movement into the intermediate zone

Question 17

Doublecortin (DCX) (microtubule binding protein) whats its role in multipolar migration ?

Answer 17

using microtubule network to move neurons

Question 18

Reelin is an adhesion protein whats its role in multipolar migration ?

Answer 18

reelin stimulates RAP1 GTPase which regulates presence of e cadherins on cell surface

e caderhins reorientate the golgi app and centromeres in the neuro to take it out of the upper intermediate zone

Question 19

LIS1 (mircotuble binding protein) whats its role in multipolar migration ?

Answer 19

it converts multipolar neuron back to bipolar when it reaches the cortical plate

Question 20

migrating promoting signals induce what in neurons ?

Answer 20

extensions in direction of migration

Question 21

The cell machinery used by neurons to migrate is driven by

Answer 21

actin polymerization and microtubule dynamics

Question 22

Actin-myosin contractile proteins are located where in migrating neurons ?

Answer 22

proximal portion of lead process

Question 23

perinuclear Tubulin cage purpose ?

Answer 23

maintaining posterior position of nucleus

Question 24

Adhesion molecules modulate neuron-glial interactions name two ?

Answer 24

reelin and astrotactin

Question 25

Cdk5 and p35 (actin binding) require for

Answer 25

neurons to penetrate the cortical plate

Question 26

Reelin (adhesion molecule) required for

Answer 26

neurons to go through subplate

Question 27

Periventricular nodular heterotopia (PH)

Answer 27

a collection of periventricular heterotopic (PH) neurons lining the lateral ventricle (V) (arrows) and a normal-appearing outer cortex. Neurological manifestation is epilepsy

Question 28

How does PH come about ?

Answer 28

``` Filamin 1 (FLN1) is required for neurons to leave the VZ during the cortical-plate stage ‘X-linked dominant inheritance’ ``` Females randomly inactivate one X chromosome in each cell that leads to two populations of cells. Normal FLN-1 gene and mutant FLN1 gene Normal cells migrate to the cortical plate and the mutant cells have a primary defect in their ability to migrate from the ventricular zone (VZ

Question 29

Lissencephaly what is it ?

Answer 29

Smooth cortex Lissencephaly typically display severe mental retardation and intractable epilepsy

Question 30

Lissencephaly what is mutated and what does this cause ?

Answer 30

Double cortin and Lis1 needed for normal migration

Question 31

Double cortex describe ?

Answer 31

Band of heterotropic neurons in the subcortical white matter and a normal cortex above - mild mental retardation less severe epilepsy In females there’s one mutant gene and one normal gene for doublecortin