GENE REGULATION L16 Flashcards
I. Prokaryotic Gene Regulation - SEQ, HD lac operon - CC positive and negative regulation II. Eukaryotic Gene Regulation - SEQ, HD, CC eukaryotic gene regulation
1
Q
induction
A
- turning on gene expression
2
Q
inducer
A
- compound that stimulates gene expression
3
Q
inducible enzyme
A
- coded for by inducible gene
- produced in response to inducer
- contrast with constitutive enzymes
4
Q
operon
A
- complex in DNA consisting of group of genes with related functions, and regulatory DNA sequences
- found in prokaryotes
5
Q
lac operon contains
A
- promoter: RNA polymerase binding site, not transcribed
- operator: “switch” sequence for gene expression, often not transcribed
- 3 genes: lacZ, lacY, lacA
6
Q
negative regulation
A
- no lactose – no expression
- with lactose – operon expressed
7
Q
repressor gene
A
- codes for repressor protein - down - regulates gene expression
- always on - constitutive expression
- not part of operon
8
Q
allolactose
A
- induces lac operon genes by inactivating repressor protein
- allows transcription to occur
- results in low levels of lac expression
9
Q
positive control of lac operon
A
- regulation by an activator that binds DNA to stimulate transcription
- lactose can be used for E, but glucose is preferred
10
Q
inactive CAP
A
- just CAP alone
11
Q
active CAP
A
- bound to cAMP
- less ATP, more cAMP
- low glucose, cAMP increases
12
Q
high glucose/no lactose
A
- no CAP
- repressed
- no expression
13
Q
no glucose/no lactose
A
- CAP
- repressed
- no expression
14
Q
high glucose/high lactose
A
- no CAP
- induced
- low expression
15
Q
no glucose/high lactose
A
- CAP
- induced
- high expression
