0222 Flashcards
Gene expression is regulated by cellular proteins known as
Tramscription factors
Control of transcription factor is dependent on
Concentration
Can deletion of a gene tell whether it is permissive or instructive
No
What is cell fate?
The fate of a cell is defined as what the cell give rise to
What is differentiation
The development of specialized cell types; commitment lf the cell
What is specification and determination
The early (reverisble) and late (irreversible) stage kf the cell-fate commitment
Instructive cues
Provide information that actively leads to program of development or differentiation
What controls dorsoventral patterning in the spinal cord
Sonic hedgehog
Perimissive cues
Required for differentiation but does not itself provide information about cell fate specification
What is it called when neuro-ectoderm becomes subdivided into specific regions
Determination
What expression shows how neuro-ectoderm becomes subdivided
Homeodomain transcription factors
What family controls limb development in drosophila
Hedgedehog family
What is the most prominent ventralizing factor
Shh
What secretes shh
First by the notochord, then by the floor plate of the spinal cord
Is there a concetration gradient gradient of shh from ventral to dorsal
Yes
What haooens when shh is missing or blocked with an antibody
There is no floor plate plate or any ventral neurons including motor neurons
What is the Shh receptor on the membrane
PTC which interacts with SMO
What inhbits SMO g protein receptor
Unoccupied PTC
What release SMO inhibiton
Binding of Shh to PTC
What transcription factor is activated by activated SMO
Gli
Signaling factors for gli proteins
Wnts
What do gli proteins do after activated by SMO
Activate or repress the transcription of genes for ptc and homeodomain transcription factors
What does gli do when it goes to domain
It represses to turn off gli and ptc
What are class 2 transcription factors
Nkx2.2 and Nkx6.1
Class 1 transcription factors
Pax6 and Dbx2
 What promotes expression of MNR2
Nkx6.1
What are the prices the expression of MNR2
Nkx2.2 & irx2
What sounds in the number to secrete BMP
Roof plate
What are the first three divisions in early brain development
Prosencephalon and mesencephalon and rhombencephalon
What are the most structurally obvious divisions in early ain development 
Rhombomeres