The Importance of Reverse Transcriptase (RT) in Retrovirus Lifecycle

Why is it important for functional RT enzyme to be packaged into the assembled virion?

A. Functional RT cannot be produced due to mutations in the viral gene that encodes RT.

B. RT is not a normal constituent of the host cell cytoplasm.

C. The host cell RT gene is not transcribed during viral infection.

D. All of the above are correct.

Answer:

The correct answer is: D. All of the above are correct.

Reverse Transcriptase (RT) is an essential enzyme in the lifecycle of Retroviruses. It plays a crucial role in transcribing the viral RNA into DNA, which is necessary for the virus to replicate and integrate into the host cell's genetic material.

It is important for functional RT enzyme to be packaged into the assembled virion because the host cell does not naturally produce this enzyme. RT is not a normal component of the host cell's cytoplasm, and during viral infection, the host cell's own RT gene, if it exists, is typically not transcribed. Mutations in the viral gene that encodes for RT can lead to ineffective replication of the virus.

Therefore, the packaging of functional RT into the virion ensures that the virus can efficiently replicate and continue its lifecycle within the host cell. Understanding the role of RT in Retrovirus infection is crucial for developing strategies to target this enzyme in antiviral treatments.