Genetics 5

Question 0

Promoter core region’s responsibility

Answer 0

• Convey position and direction.

- Included in the core region are the non-palindromic TATA box and BRE sequences.

Question 1

How does the RNA polymerase know where to bind and what direction to go?

Answer 1

The promoter contains consensus sequences that are recognized by different elements

Question 2

TATA box

Answer 2

Found 26-31 base pairs before transcription initiation site.

• Where supporting actors (TFs) bind in order to recruit RNA Polymerase
• All sequences have a TATA binding site, but not all have the CCAAT box.

Question 3

CCAAT

Answer 3

• non-palindromic promoter element
• contained in the proximal promoter.
• consensus sequence typically found in heavily regulated genes.

Question 4

GC Box

Answer 4

• contained in proximal promoter

- found in housekeeping genes.

Question 5

Eukaryotic Polymerase II

Answer 5

produces mRNA, more highly regulated

Question 6

How is the polymerase recruited?

Answer 6

• By using general TFs to create an alluring nest for the polymerase.
• More desirable environment= upregulated transcription

Question 7

Once initiation complex is ready, it needs to…

Answer 7

1) recruit nucleotides
2) Activate the helicase (TFIIH kinase–> ATP-dep unwinding via phosphorylation of CTD–> EF release)
-

Question 8

Mediator Elements

Answer 8

• Required for eukaryotic transcription.
• Contain tail/middle/head groups that overlap with basal promoter/transcriptional elements.
• Function to coordinate initiation factors to create favorable environment for Pol binding to DNA
• Doesn’t bind to DNA directly: mediates protein-protein interaction

Question 9

Chromatic remodeling complex

Answer 9

• Works with helicase and topoisomerases to unpackage DNA

- Strain managed by topoisomerases to facilitate strand separation

Question 10

How to create mRNA from precursor-mRNA

Answer 10

Add 5’ 7-methyguanosine cap, a poly-A tail, and splice out introns

Question 11

5’ cap

Answer 11

• Aids in mRNA nuclear export
• protects from 5’ to 3’ exonuclease degradation in cytoplasm
• targets transcripts to ribosome for translation

Question 12

poly-A tail

Answer 12

• Participates in termination of transcription
• aids mRNA nuclear export
• Protects from 3’ to 5’ exonuclease degradation in cytoplasm
• targets transcripts to ribosome for translation

Question 13

“RNA Factory” meaning

Answer 13

The idea the the protein brings all the factors needed to produce mRNA via phoshorylation of the CTD of the RNA Pol.

• very highly regulated
• also creates binding site for termination proteins

Question 14

First sign of slowed transcription

Answer 14

Inhibition of poly-A tail adenylation

-mRNAs with longer Poly-A tails are less likely to be degraded, thus more likely to be translated

Question 15

Which RNA codes for proteins?

Answer 15

mRNA

Question 16

Which RNA synthesizes proteins?

Answer 16

rRNA, tRNA

Question 17

Which Eukaryotic RNA polymerase mostly transcribes rRNAs?

Answer 17

I

Question 18

Which Eukaryotic RNA Polymerase transcribes rRNA subunits, most tRNAs, and snRNAs?
I

Answer 18

III

Question 19

TFIID

Answer 19

Binds to directionality core promoter sequences

-Largest of the TFs

Question 20

TBP

Answer 20

Part of TFIID

Recognizes TATA box

Question 21

Interactions between TFs

Answer 21

the complex of TFs overlaps entire 5’ flanking
region, initiation site, and some sites downstream of initiation site in order to create
an environment RNA polymerase can bind to

Question 22

TFIIH

Answer 22

Contains DNA Helicase

• dependent on ATP
• Unwinds DNA at transcription start point
• kinase activity that phosphorylates CTD of RNA Pol II

Question 23

Translation won’t begin until….

Answer 23

Poly A tail binds to 5’ cap: stabilizes mRNA