Eukaryotic Transcription Regulation Part 1 Flashcards
1
Q
gene-specific transcription factors
A
- stimulate or inhibit transcription by RNA pol II
2
Q
2 functional domains of gene-specific transcription factors
A
- DNA binding domains
- transcription activation domains
3
Q
other domains of gene-specific transcription factors
A
- dimerization domain
- binding sites for effectors
4
Q
DNA binding domains percentage
A
- 80% of all transcription factors belong to 4 families
5
Q
4 families
A
- helix-turn-helix
- zinc-containing modules
- bZIP motifs
- Helix-loop-helix
6
Q
three types of activation domains
A
- acidic domains
- glutamine-rich domains
- proline-rich domains
7
Q
functional domains within transcription factors can be “swapped”
A
- they are independent modules.
8
Q
transcription factors interact
A
- to form protein dimers to facilitate binding to a DNA target site
9
Q
specific factors bound to different DNA target sites
A
- collaborate to stabilize a transcription complex.
10
Q
affinity of binding between a protein and DNA
A
- depends on the number of protein-DNA contacts
11
Q
doubling the contacts by using a DNA dimer
A
- quadruples the affinity between the protein and DNA
12
Q
most activators concentration
A
- most have to work at very low concentrations in the nucleus
- this helps to dimerize
13
Q
dimerization of DNA binding proteins
A
- incapable of binding DNA as monomers
- must first dimerize to bind DNA
14
Q
many classes of DNA binding proteins contain
A
- alpha helix that contacts the major groove
15
Q
DNA binding protein length and binding
A
- DNA-binding domains are usually short polypeptide chains of ~ 100 amino acids
- bind to short DNA regions
