Developmental neurobiology

Question 1

How do we understand neural circuits

Answer 1

We need to understand how the nerves and circuits are assembled in space and time

Question 2

When does the building of nerves happen

Answer 2

In embryogenesis

Question 3

What are progerartive cells

Answer 3

Cells that differentiate into the nerves

Question 4

When can the early brain and spinal chord be seen

Answer 4

4-5 weeks post fertilisation

Question 5

What are model organisms

Answer 5

Vertebrates other than humans in which we can analyse their generation and assembly

Question 6

What can you see 5 weeks post fertilisation

Answer 6

Anterior and posterior axis and dorsal parts of the nervous system

Question 7

What is cell differentiation

Answer 7

The process by which cells become different from each other and acquire specialised properties

Question 8

What are the extrinsic factors

Answer 8

Signals

Question 9

What are the intrinsic determinants

Answer 9

Transcription factors

Question 10

What are loss of function studies

Answer 10

We get rid of each external factor one at a time and we ask is the outcome still the same

Question 11

What do loss of function and gain of function studies tell us

Answer 11

What the function of a cell is

Question 12

What is gain of function

Answer 12

If we add or replace factors and get the same outcome

Question 13

What is neural induction

Answer 13

In early development when some ectodermal multipotent cells change fate and become neural stem like cells

Question 14

What is the key transcriptional factor active downstream of the BMP signalling pathway

Answer 14

Phosphorylated SMAD157

Question 15

What are the antagonists that mop of up the BMPS

Answer 15

Chordin, noggin, follistain and GSC

Question 16

How can removing a factor generate a new transcriptional response

Answer 16

Happens when you remove an inhibitor of an inhibitor

Question 17

What are the transcription factors that mark the neural stem cells called

Answer 17

sox2

Question 18

What is gastrulation

Answer 18

Is the process which transforms the embryo from a one dimensional layer of cells into a multilayered embryo in which the adult body plan is recognisable

Question 19

What is the process of neuralation linked to

Answer 19

Gastrulation

Question 20

What does the transcriptional signiture tell us

Answer 20

What the cell is and at what stage its at

Question 21

Whats the best way to characterise a cell

Answer 21

through their mRNA and protein signatures

Question 22

Whats an induced pluripotent cell

Answer 22

A cell that you take from an adult and put in factors which make it a pluripotent identity

Question 23

What do organiser cells differentiate into as the neural plate is being induced

Answer 23

Prechordal mesoderm and notocord

Question 24

What do organiser cells transcribe and secrete

Answer 24

BMP antagonists

Question 25

What do the prechordal mesoderm cells secrete as well as BMP antagonists

Answer 25

Wnt antagonists for example Dikkopf

Question 26

What are posterior parts of the embryo exposed to What are the anterior parts exposed to What does this lead to

Answer 26

High levels of Wnts Wnt antagonists Creates a gradient

Question 27

What does Otx2 mark

Answer 27

Marks cells at the anterior end, cells that are going to become the brain

Question 28

What experiments have been done to test that promoting the brain is caused by Wnt antagonists?

Answer 28

Experiments on zebra fish embryos and mice

Question 29

What is controlling HOX genes

Answer 29

Wnt signals

Question 30

Where were HOX genes first identified

Answer 30

Drosophila

Question 31

Why do we study the spinal cord

Answer 31

Its simple and long in comparison to the brain

Question 32

What cell forms at the border of the surface epidermis

Answer 32

Neural plate border cells

Question 33

What do neural plate border important for

Answer 33

Neural crest formation and peripheral system development Roof plate formation and dorsal neural tube patterning The closure of the neural tube

Question 34

What do neural plate border cells give rise to

Answer 34

neural crest cells

Question 35

What are roof plate cells important for

Answer 35

Patterning and regionalisation

Question 36

Whats the first transcription factor that turns neural plate border cells on

Answer 36

MXS and its transcriptionally activated at the intermediate levels of MBP signalling

Question 37

What other transcription factors are upregulated in the neural plate border cells

Answer 37

c-Myc: governs cell proliferation id: giving cells and snail: gene that makes cells go under eptithlial to mesenchymal cell transition

Question 38

What do neural crest cells give rise to

Answer 38

Schwann cells, melanocytes, osteoblasts and neurons in the peripheral and enteric nervous system

Question 39

What are the different cell tyoes generated determined by

Answer 39

The position of neural crest cells, time of gerneation and migritory pathways

Question 40

Where are motor neurons always born

Answer 40

In the ventral part of the spinal cord

Question 41

Morophogen definition

Answer 41

A secreted signal made by source cells

Question 42

What are the two models for how a single molecule can convey positional information

Answer 42

The french flag model Reaction diffusion model

Question 43

Whats the generic signal transduction pathway

Answer 43

A signal binds to a receptor that activates a signal transduction pathway leading to rapid cellular responses

Question 44

What must a morphogen be able to do

Answer 44

To assume at least two different fates

Question 45

What does neurogenesis mean

Answer 45

The birth of a neurone

Question 46

What are the 3 different cells proginitors give rise to

Answer 46

Neurons, glia and astrocytes

Question 47

Do all proginitors become neurones?

Answer 47

No

Question 48

Whats the movement prolifererating proginitors undergo?

Answer 48

Interkinetic migration

Question 49

What can happen once a cell has become a radial glia cell

Answer 49

It can divide symmetrically or assymetrically

Question 50

What transcription factors directly regulates the expression of delta genes

Answer 50

Acheate-scute proteins

Question 51

What are the two classes of migration

Answer 51

Tangential and radial

Question 52

What happens if migration goes wrong

Answer 52

You get a brain condition known as Lissencephaly

Question 53

What is the cerebellum derived from

Answer 53

Roof plate and neural crest cells migrating out from the roof plate of the spinal cord

Question 54

What hypothesis did Weis propose

Answer 54

The resonance theory

Question 55

What hypothesis did Sperry propose

Answer 55

The chemo affinity theory

Question 56

What did sperrys experiment involve

Answer 56

Cutting the optic nerve and removing the temproal retina allowing the nasal axons to grow back

Question 57

Whats the cajal growth cone

Answer 57

The growing tip of the axon which cajal proposed sensed cues in the environment

Question 58

What are the two types of actin in the peripheral region

Answer 58

Lamella and filopodia

Question 59

What are the 4 factors of axon guidance

Answer 59

Contact attraction, contact repulsion, chemoattraction and chemorepulsion