Gene Regulation II Flashcards
What features are common to transcription factors?
Acidic and basic amino acids (H bond with DNA) within regions of the protein - specific sequences and 3-D structure
What are 2 examples of transcription factor structures?
Zinc finger
Helix-turn-helix
What is the DNA sequence that is recognized by NFkB?
GGGGACTTTCCC
What type of bonds are important in DNA/protein interactions?
Hydrogen bonds
What are the 4 transcription factor structural domains?
Helix-turn-helix
Zinc finger
Leucine zippers
Activation domains
What structural shape do steroid hormone receptors have?
Zinc finger
What are leucine zippers involved in?
Protein/protein interactions
What do activation domains interact with?
RNA polymerase
Highly acidic OR glutamine-rich regions
What shape do homeodomain proteins take?
Helix-turn-helix
What are the 3 homeodomain proteins mentioned?
Hox
Msx-1
Barx-1
What are the 4 steroid hormone receptors mentioned? What shape do their domains take?
ER, PR, AR, GCR
Zinc finger
What is the one example given of a receptor that is in leucine zipper shape?
AP-1
What is the procedure to detect DNA/protein interactions in a gel mobility shift assay?
Nuclear proteins are extracted and incubated with a specific, tagged DNA consensus sequence
DNA/protein mixture is loaded into a non-denaturing polyacrylamide gel
DNA migrates quickly
DNA+protein migrates more slowly
What are the 8 steps of binding for activation complexes, as well as RNA polymerase (Pol II)?
- Activators
- Chromatin modifiers
- Coactivator complex (mediator)
- TATA binding protein (TBP) & TFIIB
- Individual basal transcription factors
- Pol II binds to Inr region
- Carboxyl terminus of Pol II complexes with mediator
- TFIIH phosphorylates Pol II & initiates transcription
What are two other names for micro-RNAs?
Small temporal RNA (stRNA)
Small interfering RNA (siRNA)
