Gene Expression Flashcards
What are the three possible levels of gene regulation?
- Transcription
- Post-transcription
- Post-translation
Bacterial genes are usually organised into clusters called…
Operons.
Genes within an operon are usually involved in the same pathway. True or false?
True.
What is polycistronic mRNA?
A single mRNA molecule with multiple genes transcribed.
What are the four main components of operons?
- Regulator
- Promoter
- Operator
- Genes
Each operon has multiple promoters. True or false?
False.
What type of operon can be easily turned off by regulatory proteins?
Repressible operons.
What type of operon can be easily turned on by regulatory proteins?
Inducible operons.
What type of molecule turns on/off the regulatory proteins?
Effector molecules.
In the lac operon, what acts as the effector molecule?
Lactose.
What does the lacZ structural gene encode?
The enzyme beta-galactosidase.
What does the lacY structural gene encode?
The enzyme lactose permease.
What does the lacA structural gene encode?
The enzyme transacetylase.
What is the regulatory component lacI?
The lac repressor.
What induces lacI?
Allolactose or IPTG.