Post-transcription initiation gene regulation in prokaryotes Flashcards
How are transcription and translation tied to each other in prokaryotes?
They’re coupled. Translation will begin as soon as a ribosome binding site is exposed
What is a leader sequence?
The 5’ untranslated region (UTR) in an RNA transcript. It’s the region between the transcription start site and the AUG of the first opening reading frame
What is a polycistronic mRNA?
A transcript with multiple open reading frames. Used in prokaryotes to coordinate the expression of different polypeptides involved in the same process from the same transcript
What is a cis-regulating RNA regulator?
The regulating piece of RNA is part of the target RNA that it is regulating
What is a trans-acting regulator?
Something else like a transcription factor that binds to the target RNA to regulate it
How does the leader sequence act as a cis RNA regulator?
It forms secondary structures through intramolecular base pairing which will influence gene expression
Do leader sequence secondary structures regulate gene expression at the level of transcription or translation?
Both
How do leader sequences regulate gene expression at the transcription level?
Attenuation. Forcing transcription to terminate early
What are the 6 classes of leader sequence gene regulation?
- Ribosome mediated
- RNA binding proteins
- Metabolite-binding riboswitches
- T-boxes
- Thermosensors
- asRNA and sRNA
Despite the different classes of leader sequence based gene regulation, what is the common mechanism?
There are two alternative secondary structures that the leader sequence can form. One promotes transcription and the other suppresses it
What is the difference between the classes of leader sequence based gene regulation?
How the alternative secondary structures form
