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Assemble first, then read

Science · Biochemistry & Molecular Biology · ages 19-21

Name ______________________ Date ____________

RNA polymerase II alone is sufficient for normal promoter-specific initiation.
Circle one: True False
In the model TATA-promoter pathway, which interaction begins assembly?
- TBP within TFIID binds TATA
- TFIIH opens DNA before TFIID binds
- Polymerase II recognises TATA without general factors
Which activities does TFIIH contribute to polymerase II initiation?
- RNA cleavage and CTD dephosphorylation
- TATA recognition and RNA polyadenylation
- Promoter opening and CTD phosphorylation
Which mechanism describes an activator increasing initiation?
- Stabilising promoter assembly
- Increasing translation of existing messages
- Slowing decay of already completed messages
A cell no longer needs new RNA from a gene. What can reducing initiation achieve directly?
- Faster removal of the gene's existing mRNAs
- Fewer unnecessary RNA chains started
- Reduced translation of each existing mRNA
Which statement correctly contrasts bacterial initiation with polymerase II initiation?
- Bacterial sigma performs the same assembly pathway as TFIID
- Polymerase II uses sigma to recognise minus 10 elements
- Sigma helps bacterial core polymerase recognise promoters
TFIIH kinase activity is lost. Which conclusion is justified before measuring RNA production?
- Productive transcription may be impaired
- Polymerase recruitment must be completely abolished
- Promoter opening must increase to compensate for the lost kinase
Kim says a promoter-proximal pause necessarily ends that RNA chain. Which correction fits regulated pausing?
- Pausing and termination release the same RNA product
- Pause release can let the existing chain continue
- Pausing changes recruitment but not elongation of that chain

Answer key

For grown-ups. Fold this page away before handing over the rest.

Assemble first, then read W1-mt_0Ky-pYgh0Y-s1

False · General transcription factors help polymerase II assemble and initiate at a promoter.
TBP within TFIID binds TATA · TBP within TFIID binds TATA at the start of this model pathway. Other promoter assembly pathways can differ.
Promoter opening and CTD phosphorylation · TFIIH contributes ATP-driven promoter opening and kinase activity that phosphorylates the CTD.
Stabilising promoter assembly · Stabilising initiation machinery can increase initiation. Translation and mRNA decay act at later expression stages.
Fewer unnecessary RNA chains started · Initiation starts RNA chains. Reducing it limits new starts, without directly removing or changing translation of existing messages.
Sigma helps bacterial core polymerase recognise promoters · Sigma assists bacterial promoter recognition. Polymerase II uses its general transcription factors instead.
Productive transcription may be impaired · The kinase supports CTD phosphorylation and initiation transitions. Its loss does not establish a complete block or a compensating increase.
Pause release can let the existing chain continue · A pause can be reversible. Release can allow the existing polymerase and RNA chain to continue elongation.