Summary
Summary Chapter 15 - Gene Regulation in Eukaryotes I: Transcription and Translation Regulation
- Course
- Institution
- Book
Chapter 15 of Genetics by Brooker.
[Show more]
Connected book
Book Title:
Author(s):
- Edition:
- ISBN:
- Edition:
More summaries for
-
Genetics, Translation Chapter 13
-
Genetic Analysis, Chapter 11
-
Cell division, Chapter 3
Seller
Followsachajacobs
Reviews received
Content preview
Chapter 15 - Gene regulation in Eukaryotes I: Transcriptional andTranslation Regulation.
15.1 Regulatory Transcription Factors
The term transcription factor is broadly used to describe a category of proteins that influence
the ability of RNA polymerase to transcribe a given gene. The general transcription factors
are required for the binding of RNA polymerase to the core promoter and its progression to
the elongation stage. In addition, eukaryotic cells possess a diverse array of regulatory
transcription factors that serve to regulate the rate of transcription of target genes.
The DNA sequences are generally known as control elements, regulatory elements or
regulatory sequences.
- Activator binds to an enhancer
- Repressor binds to a silencer
Combinatorial control is the phenomenon that genes are regulated by many factors.
Structural features of regulatory transcription factors allow the to bind to DNA.
Domains are regions of proteins which have a specific function. When a domain or portion of
a domain has a very similar structure in many different proteins, the structurally similar
region is called a motif. The α-helix is frequently occuring in transcription factors, because it
has a proper width to bind into the major groove of the DNA double helix.
Two identical transcription factors may come together to form a homodimer, or two different
transcription factors can form a heterodimer.
Certain motifs promote protein dimerization. The leucine zipper and helix-loop-helix motif
both promote that.
The zinc finger motif can recognize DNA sequences within the major groove.
Regulatory transcription factors recognize regulatory elements that function as
enhancers or silencers. Enhancers serve to increase transcription, and their action is
called up regulation. Silencers serve to inhibit transcription, and their action is called down
regulation. Many regulatory elements are orientation-independent, or bidirectional. This
means that the regulatory elements functions in the forward or reverse direction.
Regulatory transcription factors may exert their effects through TFIID and mediator.
- Regulation via TFIID
- Activator proteins can enhance the ability of TFIID to initiate transcription. It
might help to bind to the TATA box or they might enhance the function of
TFIID in way that facilitates its ability to recruit RNA polymerase II. Activator
proteins exert their effects by interacting with coactivators, proteins that
increase the rate of transcription but do not directly bind to DNA itself.
- Coactivators typically contain a transactivation domain that promotes the
activation of RNA polymerase, often by interacting with general transcription
factors.
- Repressors inhibit the function of TFIID. They could exert their effects by
preventing the binding to the TATA box or by inhibiting the ability of TFIID to
recruit to the core promoter.
- Regulation via mediator
- A mediator mediates the interaction between RNA polymerase II and
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller sachajacobs. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $4.34. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
67474 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now