Ch11 protein synthesis

Question 1

How are the majority of viral mRNAs translated?

Answer 1

The majority of viral mRNAs are translated by 5’-end-dependent mechanisms.

Question 2

What are regions in some viral RNAs where ribosomes bind independently of the 5’ end called?

Answer 2

Internal ribosome entry sites (IRESs) allow ribosomes to bind independently of the 5’ end in some viral RNAs.

Question 3

What mechanisms do some viruses utilize to expand their coding capacity from a single RNA genome?

Answer 3

Unusual translation mechanisms in viruses allow coding of multiple polypeptides from a single RNA genome.

Question 4

What is a common occurrence in virus-infected cells regarding alterations in the cellular translational apparatus?

Answer 4

Alterations in the cellular translational apparatus are common in virus-infected cells.

Question 5

Do viral genomes encode the complete translational apparatus?

Answer 5

No viral genome encodes the complete translational apparatus.

Question 6

In what direction does translation occur as the mRNA template is read?

Answer 6

Translation occurs in a 5’ → 3’ direction as the mRNA template is read.

Question 7

What is typically found in the 5’ untranslated region (UTR) of eukaryotic mRNAs?

Answer 7

Eukaryotic mRNAs typically have a 5’ untranslated region (UTR) containing RNA secondary structures.

Question 8

What signals the start and end of the translated region in mRNA?

Answer 8

The translated region begins with an initiation codon and ends with a termination codon (stop codon).

Question 9

What is found at the end of the 3’ untranslated region (UTR) of mRNA?

Answer 9

The 3’ untranslated region (UTR) of mRNA ends with a poly(A) tail.