Gene regulation Flashcards
1
Q
What are housekeeping genes?
A
- cells that express necessary basic functions like metabolism, transcription, ect.
2
Q
How do different cells determine what genes will express and what they wont?
A
- there are several points in the transfer of genetic info from when it is DNA to a protein
- at these points you can see the rate of flow of information…
- BUT main way to determine regulation is transcription
3
Q
TATA box
A
- eukaryote promoter
- has 3 polymerases
- a sequence of DNA found in the core promoter region of genes in archaea and eukaryotes
4
Q
What are two types of DNA elements that control transcription and are unique to eukaryotes?
A
- enhancers
- silencers
- act at a great distance and act at either orientation
- bind transcription factors that determine what proteins are synthesized to what tissues
5
Q
How do histones contribute to controlling transcription?
A
- DNA is wrapped around the histones to form nucleosomes - which effects the ability of polymerase to transcribe DNA
6
Q
How do nucleosomes control transcription? What are two examples of this happening?
A
- They can bind to some transcription factors and inhibit it - inhibits transcription
- heterochromatin - DNA stains darkly
- euchromatin - DNA lightly stained
7
Q
Barr Body
A
- inactivated chromosome
8
Q
What is the whole purpose of controlling transcription?
A
- control so you can regulate genes and see what does what
9
Q
What are 3 post transcriptional mechanisms of gene regulation?
A
- Alternative splicing: when part of the exon is spliced out with the intron
- RNA stability: a cell has mechanisms for recognizing specific mRNA
- Translation control: Cells will make RNA that is able to bind to complementary RNA and block its translation
10
Q
Post translation mechanisms of gene regulation?
A
- some proteins are “destroyed on schedule” by a proteasome
- some proteins of phosphylated by kinases
- some proteins are selectively degraded
