Question 1
1.

Many of the larger DNA viruses are able to enhance viral protein translation by coding for
ribosomes that selectively translate viral proteins.
Answer
True
False
2 points

Question 2
1.
A viral messenger RNA has the following sequence:
AUG AGU GGG GCC CAU GGG AAA CCC AGG UUU
The following proteins are produced:
MetAsnGlyAlaHisGlyLysProArgPhe
MetGlyAsnProGly
What is the mechanism that generates this diversity?
Answer
A. Polyprotein Synthesis
B. Leaky

Scanning
of Termination
D. Ribosomal frameshift
C. Suppression

2 points

Question 3
1.

Some viruses are able to initiate translation at sites other than AUG(Methionine)?
Answer
True
False
2 points

Question 4
1.
A viral messenger RNA has the following sequence:
AUG AGU GGG GCC CAU GGG AAA CCC AGG UUU
The following proteins are produced:
MetAsnGlyAlaHisGlyLysProArgPhe…
MetAsnGlyAlaProTrpGluThrGlnVal…
What is the mechanism of diversity in translation of this viral mRNA?
Answer
A. Ribosomal Frameshift
B. Leaky

Scanning
C. Reinitiation
D. Suppression of Termination
2 points

Question 5
1.

The genomes of (+) RNA viruses can be translated immediately upon cellular entry, even though they do not possess a 5'
7-methylguanosine cap due to the presence of this structure at the 5' end of the genome [x].
Answer
2 points

Question 6
1.

Most viral infections induce activation of the eIF2a kinase PKR which halts protein translation in
an infected cell. Which of the following mechanims enable viruses to evade the antiviral effects
of PKR (Select all that apply)?
Answer
A Viral
.
B. Viral

protein inhibits eIF2a phosphatase.

proteins inhibit dsRNA binding to PKR
produces its own kinase that phsophorylates eIF2a.
Viral protein binds to PKR dsRNA binding site and activates PKR autophosphorylation.

C. Virus
D
.
E. Viral

proteins act as pseudo-substrates that inhibit PKR kinase activity
2 points

Question 7
1.

Describe how picornaviruses are able to produce multiple proteins from a single mRNA (Limit
3-5 sentences).
Answer
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2 points

Question 8
1.

The figure below depicts an SDS-PAGE protein gel in which total cell protein is visualized at
various time points after a viral infection. The protein bands labeled 1A, 2 and VP3 are all viral
proteins. Explain in 2-4 sentences what is occurring in this figure and why it is advantageous to
the virus

Answer
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2 points

Question 9
1.

Match the following with the translation initiation complex
Answer

A

B

C

Answer
Cellular
A.
Translation
Initiation Complex
Read Answer Items for B.
Question 9
C.
Picornavirus

Translation
Initiation Complex
Read Answer Items for
Question 9

Flavivirus/Hepatitis
C Virus Translation
Initiation Complex
Read Answer Items for
Question 9
2 points

Question 10
1.

The figure below demonstrates various mechanisms viruses have evolved to inhibit translation of
host proteins. Describe in 2-3 sentences each how the picornavirus 3C protein and the HIV
protease inhibit cellular host translation.

Answer
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2 points