Life Cycle of a Retrovirus

Question 1

How do retroviruses replicate?

Answer 1

use of a reverse transcriptase to copy their genomic sequence into DNA for insertion in the host chromosome

Question 2

Step 1

Answer 2

Virion attaches to the host cell

Question 3

Step 2

Answer 3

Virion enters cell; uncoating releases two + strand RNA, reverse transcriptase, integrase, protease

Question 4

Step 3

Answer 4

Reverse transcriptase copies viral RNA to make dsDNA

Question 5

Step 4

Answer 5

dsDNA is inserted into host genome by viral integrase; provirus is replicated when host cell replicates; provirus does not excise from host genome

Question 6

Step 5

Answer 6

Provirus can be transcribed and translated

Question 7

Step 6

Answer 7

Assembly/maturation

Question 8

Step 7

Answer 8

Release; budding; retrovirus acquires envelope with attached spikes

Question 9

What are the three proteins in retroviruses?

Answer 9

reverse transcriptase, protease, integrase

Question 10

When is the provirus replicated?

Answer 10

when the host cell replicates

Question 11

Does the provirus excise from the cell?

Answer 11

no