Deck 12: Gene Transcription and RNA Modification

Question 1

What modifications act to stabilize eukaryotic mRNA?

A)Alternative splicing
B)RNA editing
C)5' capping
D)Polyadenylation
E)Trimming

Answer 1

D

Question 2

RNA is complimentary to

A)Regulatory sequences
B)Termination sequences
C)The coding strand of DNA
D)The template strand of DNA

Answer 2

D

Question 3

The consensus sequences are 5'TTGACA3' and 5'TATAAT3' at -35 and -10 respectively. Which of the following would be most easily recognized by $\sigma$ factor?

A)5'TTGAAA3'
B)5'TAAATT3'
C)5'TATATA3'
D)5'TTCAGA3'

Answer 3

5'TTGAAA3'

Question 4

What is the catalytic subunit of prokaryotic RNA polymerase?

A)a
B)b
C)b'
D) $\sigma$

Question 5

A ribozyme is a catalytic protein that assists in the processing of tRNA.

Question 6

The holozyme is formed when the core enzyme associates with

A)Start codons
B)b
C)b'
D) $\sigma$
E)a

Question 7

A mutation in TFIIIE could result in

A)a failure of the RNA polymerase to bind to TFIIB
B)a failure of the RNA polymerase to maintain an closed complex
C)a failure of the RNA polymerase to maintain an open complex
D)no effect on transcription

Question 8

Where does the process of transcription initiate?

A)Promoter
B)Terminator
C)Regulation sequences
D)Transcription factors

Question 9

What region in eukaryotic genes usually contains the majority of regulatory elements?

A)0 to 50
B)-50 to 0
C)-50 to -100
D)-100 to -150

Question 10

If a nucleotide in a eukaryotic mRNA coding sequence does not appear in the genomic DNA sequence the most likely modification to have occurred is

A)Alternative splicing
B)RNA editing
C)5' capping
D)Polyadenylation
E)Trimming

Question 11

What sequences are not considered to be regulatory elements?

A) Enhancers
B) Silencers
C) Core promoters
D) Cis-acting elements
E) General transcription factors

Question 12

Which RNA encodes the sequence of amino acids for a functional protein?

A)tRNA
B)snRNA
C)mRNA
D)rRNA
E)scRNA

Question 13

A gene that undergoes rho-dependent termination has a mutation in the rut site. How will this influence transcriptional activity?

A)Transcription will terminate normally as Rho termiantion relies on the rut site to enhance termination; it is not essential for termination
B)Transcription will stop immediately because RNA polymerase will sense there is a mutation
C)Transcription will continue until another termination sequence, either Rho dependent or independent is reached
D)There will be no transcription initiation

Question 14

What RNAs do each eukaryotic RNA polymerase produce?

A)RNA pol I - mRNA RNA pol II - tRNA and 5s rRNA
RNA pol III - rRNA
B)RNA pol I - rRNA RNA pol II - tRNA and 5s rRNA
RNA pol III - mRNA
C)RNA pol I - mRNA RNA pol II - rRNA
RNA pol III - tRNA and 5s rRNA
D)RNA pol I - tRNA and 5s rRNA RNA pol II - mRNA
RNA pol III - rRNA

Question 15

Which molecules are not part of the closed promoter complex?

A)RNA polymerase
B)Transcription factors
C)Double helix DNA
D)Single-stranded DNA

Question 16

In eukaryotic organisms, the processing of the 45S rRNA into 5.8S, 18S, and 28S rRNA occurs where?

A)In the cytoplasm
B)In the nucleolus
C)In the endoplasmic reticulum
D)In the Golgi body
E)Throughout the cell

Question 17

What is the difference between the allosteric and torpedo models of eukaryotic transcritponal termination?

A) The allosteric model is that RNA pol II becomes destabilized after transcription of the poly A signal sequence while the torpedo model is that the polymerase is physically removed from the DNA
B) The torpedo model is that RNA pol II becomes destabilized after transcription of the poly A signal sequence while the allosteric model is that the polymerase is physically removed from the DNA
C) The allosteric model is that RNA pol II becomes destabilized after transcription of the stop codon sequence while the torpedo model is that the polymerase is physically removed from the DNA
D) The torpedo model is that RNA pol II becomes destabilized after transcription of the stop codon while the allosteric model is that the polymerase is physically removed from the DNA
E) The only difference between the two models is the proteins that are involved in removing the RNA pol II from the DNA

Question 18

What basal transcription factor is a helicase?

A)TFIID
B)TFIIH
C)TFIIF
D)TFIIB

Question 19

Which region of DNA contains the coding information for a protein in a eukaryote?

A)Exons
B)Introns
C)Enhancers
D)Promoters

Question 20

Most eukaryotic genes are collinear.

A)True
B)False
C)It is unknown at this time

Question 21

What is unusual about the 5' cap found on almost all eukaryotic mRNAs?

A) The nucelotide added is a guanine methylated at N7 and the bond is created between the phosphate group on the guanine and the phosphate on the terminal nucleotide
B) The nucelotide added is a guanine methylated at N7 and the bond is a typical phosphodiester bond with the terminal nucleotide
C) The nucelotide added is anadenine methylated at N7 and the bond is created between the phosphate group on the guanine and the phosphate on the terminal nucleotide
D) The nucelotide added is an adenine methylated at N7 and the bond is typical phosphodiester bond with the terminal nucleotide

Question 22

What structural motif is most commonly used by transcription factors in binding to DNA?

A)Zinc-finger
B)Helix-turn-helix
C)Leucine zipper
D)Homeodomain

Question 23

What do both the rho-dependent and rho-independent mechanisms of termination have in common?

A)Terminate transcription immediately after the stop codon
B)A sequence rich with A-U base pairs
C)Both require a helicase to separate the DNA-RNA complex
D)Formation of a stem-loop structure

Question 24

What is the purpose of phosphorylating the carboxy terminal domain (CTD)?

A)Convert from initiation to the elongation stage
B)To aid in transcriptional initiation
C)Phosphorylate transcription factors
D)To aid in promoter recognition

Question 25

The RNA polymerase forms a closed complex during the process of elongation during transcription.

Question 26

What is the correct order of elements that comprise a functional protein encoding gene in a prokaryote?

A) Promoter, regulatory region, transcribed region, terminator
B) Regulatory region, promoter, transcribed region, terminator
C) Regulatory region, promoter, terminator, transcribed region
D) Promoter, transcribed region, regulatory region, terminator

Question 27

Basal transcription in eukaryotes involves the action of only the core promoter.

Question 28

In the process of RNA editing adenine or cytosine may be deaminated and the result is

A)Adenine is changed to inosine and cytosine is changed to thymidine
B)Although both bases are covalenty changed there is no alteration in the tRNAs the modified bases may engage
C)The new bases effectively result in new codons
D)Answers adenine is changed to inosine and cytosine is changed to thymidine and the new bases effectively result in new codons are correct (Although both bases are covalenty changed there is no alteration in the tRNAs the modified bases may engage is incorrect)
E) Answers adenine is changed to inosine and cytosine is changed to thymidine and although both bases are covalenty changed there is no alteration in the tRNAs the modified bases may engage are correct (The new bases effectively result in new codons is incorrect)

Question 29

What is a mechanism by which tRNA is processed inE.coli

A)RNaseP acts as an endonuclease
B)The recognition sequence of RNaseD is 3'CCA5'
C)RNAseD acts as an endonuclease
D)tRNA is not processed in

Question 30

The term ribozyme is given to catalytic RNA molecules.

Question 31

The Prinbow box contains a CACAAC consensus sequence located in the -100 region of the promoter.

Question 32

What snRNP holds the exons in place so that they can be connected after the intron is removed?

A)U1
B)U2
C)U5
D)U6

Question 33

What enables the splicing of group I and II introns?

A)Spliceosomes
B)Ribozymes
C)snRNA
D)Poly-A tail

Question 34

What occurs In both prokaryotic and eukaryotic tRNA maturation?

A) The pre tRNA molecule is trimmed by exo and endonucleases
B) The pre tRNA is spliced
C) The mature tRNA is capped at the 5' end
D) There is extensive RNA editing

Question 35

The process of RNA editing can alter the base sequence of the mRNA following transcription.

Question 36

An R loop experiment was performed on two different mRNA's. The first showed one R loop, while the second showed two R loops separated by a region of double-stranded DNA. What is the composition of these two mRNA's?

A)The first contains no introns and the second two introns
B)The first contains no introns and the second one intron
C)The first contains one intron and the second two introns
D)The first contains two introns and the second one intron

Question 37

The unit of transcription at the molecular level is the gene.

Question 38

Sigma factor belongs to a general group of proteins called the transcription factors.

Question 39

What would be the effect on in vitro transcription if you replaced the entire TFIID protein with the single subunit TBP?

A)Transcription could not be terminated
B)The initiation complex could not form
C)RNA polymerase II would never be recruited to carry out elongation
D)There would be no effect

Question 40

The formation of open complex usually forms in GC rich regions of DNA due to the decreased number of hydrogen bonds.

Question 41

What kind of promoter is being used in this experiment?

A)Eukaryotic
B)Prokaryotic
C)Cannot tell from the information given
D)Neither eukaryotic nor prokaryotic

Question 42

The absence of a band when the linker is present at about -25 indicates that

A) This region is critical for the in vitro transcription reaction
B) this region is not critical for the in vitro transcription reaction
C) it is not possible to determine if this region is critical for in vitro transcription
D) the linker interfered with transcription

Question 43

The results obtained when the linker was cloned between -50 and -100 indicate that

A)this region is not critical for transcription but can enhance transcription
B)the assay failed
C)when cloned in this region the linkers had a transacting effect
D)the results of the assay were variable and this is just due to random variation in the assay

Question 44

The rationale for including the plasmid that was not cloned with the linker was

A) the plasmid without the linker served as a positive control to demonstrate that the assay was performing as expected
B) that the plasmid was used to make sure there was no RNA degradation
C) the plasmid was used to make sure there was no DNA degradation
D) the plasmid was included as a carrier to help separate the RNA that was produced from the unincorporated radioactive nucleotides.