Neurodevelopment Flashcards
What do you use Golgi staining for?
distinguish between different cell types
What do you use Nissl staining for?
distinguish number of cells
How many neurons do we have?
10 to the power of 11
what are the steps or neural development?
Different parts of nervous system develop to local program, neurons extend axons and dendrites, networks or connections are made by synapses, synapses are refined
What happens to the neuron after exposed to antidepressive?
Increased dendritic complexity
What does the neural tube give rise to?
Anterior neural tube: Brain and eyes, posterior neural tube: spinal cord
What gives rise to the peripheral nervous system?
Neural crest
How is the dorsal/ventral pattern established?
opposite gradient morphogens in neural tube; Dorsal: BMP and Wnt and Ventral: Sonic hedgehog
What drives the differentiation process of neurons from progenitor cells?
combinations of Transcription regulators
What is temporal patterning? And example
Intracellular program changes the character of a
progenitor cell over time; mammalian cerebral cortex
Explain the temporal character of the cerebral cortex
Wall cell of the neural tube proliferate, Later born neurons crawl past the earlier born neurons to settle
farther out
How do newborn neurons migrate?
Along the radial glial cells
How do newborn neurons migrate?
Along the radial glial cells
Does the cortical layering process also happen in vitro and what does it mean?
Yes, it means that it is intracellularly programmed
What is a growth cone?
The spiky enlargement of the tip of dendrites and axons
What is the function of growth cone?
To produce the crawling movement and direct the tip along the proper path
What is the function of growth cone?
To produce the crawling movement and direct the tip along the proper path
What are comissural axons?
Axons that cross from one side of the body to another (incrucisati)
How are the axonal growth cones oriented in the developing spinal chord?
ventrally towards the floor plate and than right agle towards brain
How are the axons attracted to the floor plate?
By secreting Netrin
How does the axon go towards the brain?
By losing sensitivity to Netrin and getting sensitivity for Slit
Who produces slit and what is its function?
Slit is produced by the floor plate and is repelling the growth cone
Who keeps Slit receptors inactive?
Protein Robo 3.1
How is a neural map created?
Target territories are created from different axons of the same bundle
Give three examples of orderly maps
retinotropic map-retinal tectum, tonotropic map-hearing and touch map-homunculus
What types of axons show specificity? What is the key difference?
Posterior, anterior do not, repulsive factors on posterior tectum
What does EphrinA-EphA mediate?
signaling for anteroposterior axis
What is DSCAM?
Self-recognition molecule in Drosophila
What use vertebrates for self-avoidance
prodcadherin
What does the target tissues of the neurons secrete that makes them survive?
Neurotrophic factor
What is the main neurotrophic factor?
Nerve growth factor
In a neuromuscular junction, what does the neuron secrete?
Agrin
What is the function of Agrin
Binds to receptors in muscle that respond back and tightens the junction-LRP4 and MuSK=> clustering of acetylcholine receptors
How is synapse elimination involved in neuromuscular junction?
Each muscle fiber first recieves input from more nerves but it is left with only one because its activity dependent and subjectit to competition
What is the Hebbian principle?
Synapse strenghtening by activity
Explain: “What fires together wires together”
When two or more neurons synapse on the same target cell, fire at the same time, they reinforce their connections. When they fire at different times they compete so one will be eliminated
Give an example of lack of input that leads to death of neurons
Lazy eye
What does synaptic pruning depend on?
synaptic communication and electrical activity
What is contact guidance?
Growth cones can take routes that have been marked by other neurites forming bundles
hat makes growth cones crawl on other axons?
Cell to cell adhesion molecules like N-CAM (immunoglobulin superfamily) and cadherin
What type of protrusions are created by growth cones?
Filopodia and Lamellipodia
