Gene Regulation II Flashcards
Where is helix-turn-helix found?
Homeodomain proteins
Used to force new production of structures like extra legs and such
Are H bonds important in DNA/protein interactions?
Yes, of course
Where are zinc fingers found?
Steroid hormone receptors
What are leucine zippers involved in?
Involved in protein/protein interactions
Always come in dimers
AP-1
What do activation domains do?
Help the structural domains Interact with RNA polymerase
Highly acidic or glutamine rich regions sometimes Proline rich as well
Are leucine zippers in mammals and yeast similar or dissimilar?
Their sequences are very similar
What are supershifts?
DNA + protein + antibody
What are shifts?
DNA + protein
What are shifts and supershifts found in?
Electrophoretic mobility shift assays (EMSAs)
Helps determine if transcription factor (NFkB) structural domains have been attached
In what order do activation complexes and RNA polymerase (pol II) bind? (8 steps)
1) Activators
2) Chromatin Modifiers
3) Coactivator Complex
4) TATA binding protein, TFIIB
5) Basal Transcription factors
6) Pol II
7) Pol II complexes with mediator
8) TFIIH phosphorylates pol II and initiates transcription
What is typical of transactivation domains on transcription factors?
Proline rich (PPP) Glutamine rich (QQQ) Acidic
What are some functions of micro RNAs?
Mediate silencing of many genes
Interact with mRNA by causing degradation of inhibition of translation
Some involved in heterochromatin formation
How is whether or not a tooth will become an incisor or molar determined?
Growth factors from overlying epithelium (FGF-8 vs BMP-4)
Homeodomain proteins in medial & distal mesenchyme (Msx-1 vs Barx-1)
What signaling promotes molars?
FGF-8 increases Barx-1
What signaling promotes incisors?
BMP-4 increases Msx-1 and decreases Barx-1
