What are the three stages of transcription?
- Initiation (rate limiting step)
- Elongation
- Transcription
What is polycistronic transcription?
Prokaryotic transcription
- Has multiple translation start sites
- Translated by RNAs into bacteria
- RNA polymerase can make multiple gene plots
What is monocistronic transcription?
How many RNA polymerases does it have?
Eukaryotic transcription
- Single translational start site
- 3 RNA polymerases
What are the different sensitivites of the three RNA polymerases to alpha amanitin?
- Pol I is not impacted
- Pol III runs well at low concentrations
- Pol II doesn’t run at all
Name two main traits of RNA pol I , and what parts of it are pretranscribed?
- creates ribosome components
- Has role in protein synthesis
pre-rRNA is pretranscribed
What parts of RNA pol II are pre-transcribed?
mRNAs
snRNAs
siRNAs
miRNAs
What are 3 main functions of RNA pol II?
- encodes protein
- RNA splicing
- Chromatin-mediated repression - translational control
What is pretranscribed in RNA pol III?
- tRNAs
- 5s RNAs
- snRNA U6
- 7S RNA
What are 4 roles of RNA pol III?
- protein synthesis
- ribosomal component
- RNA splicing
- signal recognition particle for insertion of polypeptides into endoplasmic reticulum
- More unknown!
What are the 4 commonalities in the 3 RNA polymerases?
- All exist in multimeric protein complexes
- Show significant similarity to bacterial subunits
- Determine function
- Elimination is lethal
Explain CTD and what we see from it
It’s the staining of the carboxy terminal domain
- unphosphorylated stain green
- phosphorylated stain red
- Overlap is yellow
Chromosome puffs are where transcription is occurring (these are red areas)
