Question

Why is it important for a retrovirus to carry its own reverse transcriptase protein instead of making it from its reverse transcriptase gene after it infects a cell?

A) Faster viral replication
B) Avoids host immune response
C) Ensures accurate reverse transcription
D) Facilitates viral integration

Answer 1

Retroviruses like HIV carry reverse transcriptase to ensure immediate DNA synthesis from its RNA genome upon infection, leading to faster viral replication.

Step-by-step explanation:

Retroviruses like HIV carry their own reverse transcriptase protein which is crucial for converting the viral RNA genome into DNA, allowing the virus to integrate into the host's genome. A direct answer to why this is important is: A) Faster viral replication.

Retroviruses are unique in that they have an RNA genome that must be converted into DNA before they can replicate within a host cell. This conversion is catalyzed by the enzyme reverse transcriptase, which is a viral protein that the host cells do not naturally produce. Therefore, the retrovirus carries its own reverse transcriptase to ensure that upon infection, it can immediately begin synthesizing DNA from its RNA genome.

If it relied on the production of reverse transcriptase from its own genes after infection, the replication process would be significantly delayed, thwarting the rapid replication that is characteristic of viral infections. Additionally, by carrying the enzyme, retroviruses avoid the delay that would occur while the host's transcription and translation mechanisms produce the enzyme from the viral genome, leading to a more efficient infectious cycle.