Deck 8: Molecular Biology and Transcription and Rna Processing

Question 1

A cell exhibits specific defects in the alternative intron splicing pathway.Which proteins are likely mutated in this cell?

A)histone proteins
B)transcription factors
C)transmembrane proteins
D)DNA binding proteins
E)SR proteins

Answer 1

E

Question 2

What is the consensus sequence for the Pribnow box from these sequences?

A)TTGATA
B)TATGAT
C)TATTAT
D)ACCA
E)TAGTAT

Answer 2

B

Question 3

Which enzyme is required to initiate 5′ capping of eukaryotic mRNA transcripts by removing the terminal phosphate group?

A)ribozyme
B)guanylyl transferase
C)methyl transferase
D)adenylyl cyclase
E)phosphodiesterase

Answer 3

B

Question 4

If you want to prevent rho-dependent transcription,which sequences would you target to mutate the rho utilization (rut)site?

A)coding region
B)start codon
C)promoter sequence
D)terminator sequence
E)stop codon

Question 5

You wish to create a mutation in which you prevent access of RNA polymerase to the gene.Which region of a gene would you target?

A)coding region
B)start codon
C)promoter sequence
D)terminator sequence
E)stop codon

Question 6

How does the antibiotic rifampicin prevent transcription of RNA?

A)Rifampicin blocks binding of RNA polymerase to the promoter.
B)Rifampicin prevents chain elongation by preventing formation of the phosphodiester bond.
C)Rifampicin prevents the chain termination,so transcripts are too long and rendered nonfunctional.
D)Rifampicin blocks ribosomal RNAs from forming functional ribosomes.
E)Rifampicin blocks translation by preventing the mRNA from being processed.

Question 7

In a given bacterium,transcription of housekeeping genes is normal,but genes involved in nitrogen metabolism,stress,and chemotaxis are disrupted.Which sigma subunit is intact?

A)σ²⁸
B)σ³²
C)σ³⁵
D)σ⁵⁴
E)σ⁷⁰

Question 8

You suspect a region of DNA contains a promoter and wish to confirm that a sequence of interest binds proteins.Which experiment would you use?

A)in situ hybridization
B)band shift assay
C)pulse-chase assay
D)Southern blotting
E)northern blotting

Question 9

Which type of research technique was used to track newly synthesized RNA within a eukaryotic cell?

A)in situ hybridization
B)band shift assay
C)pulse-chase
D)Southern blotting
E)DNA footprint protection assay

Question 10

Following a DNA footprint protection assay,which banding pattern would you expect to see if you identify a potential promoter region?

A)

B)

C)

D)

E)

Question 11

Nucleoli contain many tandem repeat copies of which genes,transcribed by RNA polymerase I?

A)mRNA
B)tRNA
C)rRNA
D)siRNA
E)all of the above

Question 12

Which region(s)of a gene are not found within the mRNA transcript?

A)promoter region
B)termination region
C)stop codon
D)promoter and stop codon
E)promoter and termination regions

Question 13

You want to design a drug that prevents transcription of mRNAs but does not affect transcription of other RNAs.What enzyme would you target?

A)RNA polymerase I
B)RNA polymerase II
C)RNA polymerase III
D)ribozyme
E)methyl transferase

Question 14

A cell has a defect in polyadenylation.Which RNA transcripts would not be affected by this defect because they are not polyadenylated?

A)histone proteins
B)transcription factors
C)transmembrane proteins
D)DNA binding proteins
E)SR proteins

Question 15

If bacteria are infected with a bacteriophage and briefly exposed to radioactive uracil,what results would you expect to see immediately after exposure?

A)radioactive mRNA in the cytoplasm
B)radioactive mRNA in the nucleus
C)radioactive DNA in the cytoplasm
D)radioactive DNA in the nucleus
E)radioactive proteins in the nuclear membrane

Question 16

Which type of mRNA is translated within a cell?

A)tRNA
B)mRNA
C)rRNA
D)siRNA
E)all of the above

Question 17

Which assay allows you to identify the exact location of the protein-binding sequence within a promoter?

A)western blotting
B)in situ hybridization
C)pulse-chase assay
D)Southern blotting
E)DNA footprint protection assay

Question 18

A gene has acquired a mutation in which the protein product has an "extra" 50 amino acids at the end.Which region of the gene was likely mutated?

A)coding region
B)start codon
C)promoter sequence
D)terminator sequence
E)stop codon

Question 19

In humans,the 30S pre-RNA transcript yields three rRNA segments following transcription and RNA cleavage.What RNA transcripts are generated by the 30S pre-RNA transcript in E.coli?

A)two rRNAs (15S each)
B)three rRNAs (5S,16S,and 23S)
C)two tRNA transcripts
D)three rRNAs (5.8S,18S,and 28S)and two tRNA transcripts
E)three rRNAs (5S,16S,and 23S)and two tRNA transcripts

Question 20

What is the -35 consensus sequence for the following sequences?

A)TTGATA
B)TATGAT
C)TATTAT
D)ACAA
E)TAGTAT

Question 21

What molecule is required for activation of rho protein?

Question 22

What proteins are bound to enhancers,forming a protein "bridge" that bends the DNA over the promoter to initiate transcription?

Question 23

miRNA is capable of regulating protein production through which process?

Question 24

One type of RNA editing involves inserting uracils into edited mRNA with the assistance of which type of specialized RNA?

Question 25

Transcription of inverted repeats produces an mRNA with complementary segments that fold to form what type of secondary structure?

Question 26

Which type of RNA interacts with nuclear proteins to form a ribonucleoprotein complex responsible for intron removal?

Question 27

What proteins bind to silencer sequences,forming a protein "bridge" that bends the DNA over the promoter and prevents transcription?

Question 28

What are the mechanisms for transcription termination in bacteria?

Question 29

What are the two chemical structures found in RNA but not DNA?

Question 30

Prokaryotes have a -10 and -35 consensus sequence in their promoter.What are the three eukaryotic promoter sequences elements (or "boxes")?

Question 31

Which three types of RNAs are found in both prokaryotes and eukaryotes?

Question 32

A plant cell exhibits defects in transcription of transfer RNA genes.Which polymerase is likely to be mutated in this cell?

Question 33

What proteins aid in the recognition of the promoter sequence and binding of RNA polymerase II in eukaryotes?

Question 34

Processing of the 30S pre-RNA transcript in humans produces what three rRNAs after enzymatic cleavage?

Question 35

Spliceosome components are recruited to 3′ and 5′ splice sites by SR proteins bound to what DNA sequences?

Question 36

The rat α-tropomyosin (α-Tm)gene produces nine different mature mRNAs proteins from a single gene using which three "alternative" mechanisms?

Question 37

You wish to prevent transcription of all three types of RNA in bacteria.How many different types of RNA polymerase would you need to inhibit?

Question 38

Catalytically active RNAs that can activate processes such as self-splicing are called what?

Question 39

Name three functional RNAs unique to eukaryotes.

Question 40

Eukaryotic promoters are diverse,which means that eukaryotes have how many different RNA polymerases?

Question 41

Describe the three main difference bacterial and eukaryotic transcripts.

Question 42

RNA polymerase is called a ________,meaning it is an intact complex with full enzymatic capacity.

Question 43

In the following prokaryotic DNA sequence,label the highlighted regions.

Using the prokaryotic DNA sequence above,describe the relationship between the highlighted regions and how mutations in each region may affect gene expression.

Question 44

What are the three types of posttranscriptional processing,and what are the consequences of preventing each of these modifications in terms of gene expression?

Question 45

Describe the mechanism(s)used by bacteria and eukaryotes for transcription termination.

Question 46

Intron self-splicing occurs when two ________ reactions excise the intron and allow exons to ligate.

Question 47

In intrinsic termination,inverted repeat DNA sequences followed immediately by a string of ________ produce an mRNA stem-loop followed by a string of ________.

Question 48

Polyadenylation begins with the binding of ________ near a six-nucleotide mRNA sequence,AAUAAA,downstream of the stop codon.

Question 49

Describe how band shift assays and DNA footprint protection assays can be used to identify promoter regions in DNA.

Question 50

The 5S rRNA and tRNA genes have internal promoters located downstream of the transcription start site,called ________.