Topic 5 Flashcards
(17 cards)
What is transcriptional regulation?
The control of turning DNA to mRNA to influence what genes are expressed.
What are 2 protiens involved transcriptional regulation and what are there functions?
Sequence specific binding promoters: bind specifically
Non sequence specific binding proteins: Can bind anywhere
What do GTFs do? What do they do in Prokaryotes? Eukaryotes?
GTFs help RNAp at many different promoters.
In Prokaryotes: sigma factors bind RNAP then go to DNA together
In Eukaryotes: Basal TFs bind promoter first, then recruit RNA polymerase
What do Regulatory TFs do? What are the different types?
Regulatory TFs regulate the rate of transcription at different promoters
Positive regulatory: Promotes transcription
Negative regulatory: Supresses transcription
What is an operon?
An operon is a set of genes in DNA controlled by a single promoter.
What does E.coli prefer to use as energy? What does it use when there is none of the preferred?
E coli prefers to use glucose as energy. When there is no glucose, they use lactose.
What is the goal of the lac operon?
The goal of the lac operon is to express the genes to break down lactose into usable energy.
When does the cell express the lac operon?
The cell expresses the lac operon when there is no glucose but plenty of lactose.
What does lactose to do the repressor?
Lactose binds to the repressor and removes it so genes can be transcribed.
What is CAP?
CAP is a positive regulator. It is controlled by cAMP levels.
What has an inverse relationship?
Glucose and cAMP have a inverse relationship.
_____ can only bind to DNA when bound to ________?
CAP can only bind to DNA when bound to CAMP.
Whats the level of expression when theres high lactose low glucose?
When there is high levels of lactose and low glucose, high expression occurs.
What happens when there is low glucose AND lactose?
When its low in both, nothing is expressed since lactose is still bound to repressor, so the operon is bound.
What happens in eukaryotic transcriptional regulation?
In eukaryotic transcriptional regulation,
1) Tfs bind far from promoter so DNA bending protiens are needed to bring them closer
2)Different combinations of these TFs are what controls transcription.
What are some simalarities between prokaryotic and eukaryotic regulation?
Some simalarities are,
1) They both use TFs to control RNAP binding
2) They have regulatory TFs and general TFs. (GTFs)
What are some differences between prokaryotic and eukaryotic regulation?
Some differences are,
1) Eukaryotes have TFs that bind far away from promoter
2) In prokaryotes, sigma factors bind RNAP first then bind promoter as a complex
3)In eukaryotes, the general TFs bind the promoter first, then RNAP binds.
