S1 Mitchell (8-17) Flashcards
Assays performed on which gene first detected chromation changes upon gene activation?
ß-globin
ChIP assays revealed that Nucleosome Free Regions (NFRs) are found where?
At promoter regions
Nucleosomes adjacent to NFRs are encriched in what?
Euchromatin markers
What are some euchromatin markers?
- AcH3K9
- MeH3K4
What is the SAGA complex?
A histone acetyltransferase complex (HAT)
Where is SAGA recruited to?
Upstream Activating Sequences (UAS)
How is SAGA recruited?
Through interaction with transcriptional activators, eg Gcn4 and Gal4
In more general terms, what is SAGA?
A co-activator
Once histones are acetylated, they are recognised by proteins with a specific domain. Which domain is this?
The bromodomain
Give some examples of proteins with the monoacetylated-histone recognising domain.
- CRMs
- TFIID
What is the catalytic component of the SAGA complex?
Gcn5
Which histones does Gcn5 directly acetylate, and for which histone is Gcn5 required indirectly for acetylation?
- H2B, H3
- H4
Name two CRMs.
- SWI
- SNF
What does the helicase activity of CRMs cause?
Nucleosome sliding along DNA
What do CRMs bind as a control mechanism?
Activation/Repression domains of TFs
In general terms, what is the Sin3/Rpd3 HDAC?
A transcriptional co-repressor
What does Sin3 do?
Allows interaction with Ume6, a URS binding transcriptional repressor.
What does Rpd3 do?
It is the catalytic histone deacetylase subunit.
Transcriptionally inactive reguions of DNA are rich in what residues?
m5CG
Methylation patters are established in the zygote. In which cells are they mainted, and how?
Stably in somatic cells.
MeCP2 binds m5CG. What does MeCP2 recruit?
Histone deacetylase or histone methyltransferase complexes
