Gene Regulation in Eukaryotes Flashcards
Eukaryotes & prokaryotes regulate genes at __________
Transcription
Eukaryotes can also be regulates when?
- Post translation
- mRNA stability
- Translation
- microRNA
- Post-translation (protein modification, protein stability)
Transcription factor
Group of proteins that influence the ability of RNA polymerase to transcribe a gene
Two types of transcription factors that can regulate RNA polymerase to bind to the promoter switch from initiation stage & elongation are what?
- General Transcription factors (GTFs)
- Regulatory transcription factors (RTFs)
General transcription factors (GTFs)
Required for RNA polymerase to bind to the promoter & its progression to the elongation stage (needed for basal transcription)
Regulatory transcription factors (RTFs)
Serve to regulate the rate of transcription
Regulation in eukaryotes is similar to prokaryotes because they have what?
- Cis-factors (enhancer & silencers)
- Trans-factors (activators & repressor)
- mRNA processing, splicing, transport, & access to ribosome
- Protein transport to proper location
In eukaryotes a regulatory transcription factor can increase the rate of transcription when an _________ binds to an enhancer
Activator
In eukaryotes regulatory factors can decrease transcription when a _________ binds to a silencer
Repressor
Combinatorial Control
When a combination of different factors determines the expression of many genes
At the level of transcription what factors contribute to combinatorial control? All 5 factors can contribute to the regulation of a single gene
- An activator
- Repressor
- Small effector molecules
- Nucleosomes
- DNA methylation
Regulatory transcription factors (activators & repressors) recognize regulatory sequences that function as ________ or ________
Enhancers or silencer
Up regulation
When enhancers stimulate transcription by 10 to 1000 folds (times)
Down regulation
When silencers inhibit transcription
Regulatory transcription factors may exert their effects through _______
TFIID
TFIID
Is a general transcription factor that binds to the TATA box & is used to get RNA polymerase to bind to the promoter
Activator proteins can enhance the ability of TFIID to start transcription by interacting with ________
Coactivators
Coactivators
Proteins that increase the rate of transcription but doesn’t directly bind to the DNA
A repressor can inhibit the function of TFIID by preventing the TFIID from binding to the __________ or inhibiting TFIID ability to make RNA polymerase 2 bind to the promoter
TATA box
The function of a regulatory transcription factor can be modulated in what 3 ways?
- The binding of small effector molecules
- Protein-protein interaction
- Covalent modifications
________ can bind to a regulatory transcription factor & promote it to bind to DNA
Small effector molecules such as steriod hormones