Bacterial Transcription Flashcards
Study for Genetics Exam 2
Transcription
Making RNA using DNA template
State all functions/characteristics
RNA Polymerase
- Carries out transcription
- Needs a template
- Does NOT need 3’ OH
- Always adds to 3’ end
- Acts as a helicase
- Synthesizes transcription
- Elongates mRNA
- Terminates sequence
RNA-like Strand
Has the same sequence as the new RNA molecule
+1 Site
Transcription initiation site
“Downstream”
- The direction of transcription
- Direction of RNA pol
Promoter
DNA sequence where initiation of transcription happens
Sigma Factor
Protein that determines efficiency of initiation transcription
Holoenzyme
Complete, functional enzyme that is catalytically active (+sigma)
Core Enzyme
Is made up of alpha and beta polypeptides
Vegetative
- Principle sigma factor
- Helps Ecoli find promoters for transcription
Heat Shock
When the sigma subunit’s temperature gets too high: proteins denature and membranes dissociate
Conserved Regions
Have a particular shape that can be recognized and bound to by sigma factors.
(-) 10 Region
Where the TATA Box is located
TATA Box
Where the double stranded DNA is separated into single strands
Consensus Sequences
Plenty of same nucleotide in one sequence
RNA Polymerase Holoenzyme
Core enzyme + sigma factor
Rho-Dependent
Uses Rho protein
State all responsibilities and traits
Rho Protein
- Termination factor protein
- Helicase activity
- Needs a protein and DNA sequence
1. Moves along RNA transcript
2. Finds the replication bubble and unwinds RNA/DNA duplex
3. Releases RNA chain
Rho-Independent
- Does not need Rho protein
- Uses sequences and inverted repeats
Hairpin-Loop
- Results from inverted repeats by Rho-Independent Factor
- “Locks up” RNA pol and disrupts the process (terminates)
