Lecture 4 Flashcards
What are RNA pol II general transcription factors?
TFIIA, TFIIB, TFIID, TFIIE, TFIIH
“Alex behaves differently even harshly”
What does the -37 to -32 region contain?
BRE
- Transcription Factor IIB Recognition Element
What does the -31 to -26 region contain?
TATA box
What does the -2 to +4 region contain?
Initiator
What does the +28 to +32 region contain?
The Downstream promoter element
What direction does transcription occur in TATA containing and TATA-less promoters?
Only occurs in one direction
What happens with other promoters (CPG islands)
Transcription can occur in both directions, however the polymerase stalls and falls of off DNA in one of the directions and proceeds in the other
How does RNA Pol II get loaded onto the promoters?
By the GTF’s
What is RNA labelled by?
Br-UTP and is sequenced
What does the plot demonstrate?
The intensity of transcription at an analyzed : uni directional synthesis of RNA
What is TSS?
Transcription start site
What are the meaning of the results?
Transcripts peak at 50 base pairs, then RNA polymerase stalls in the +50 to +200 base pair region before elongating further
What do CPG islands occupy?
The promoters of about 70% of the genes in vertebrates
What do CPG rich DNA contain?
Less nucleosomes making it easier to transcribe
Where does transcription initiate on a CPG island?
Initiate at any position
Although it initiates in any position, where does transcription proceed?
On the Open reading frame
What was the second plot demonstrating in the experiment?
Labelled RNA with Br-UTP and sequenced
Plot represented the intensity of transcription over an analyzed locus: bi-directional synthesis of RNA on a CPG island
