Question

HIV is a retrovirus. Which best describes the flow of genetic information from viral transmission to the production of viral protein?

• A. Viral DNA $\to$ Viral RNA $\to$ Protein
• B. Viral RNA $\to$ Viral DNA $\to$ Host DNA $\to$ Host RNA $\to$ Protein
• C. Viral RNA $\to$ Host DNA $\to$ Protein
• D. Viral DNA $\to$ Host DNA $\to$ Host RNA $\to$ Protein

Answer 1

The correct option is B Viral RNA $\to$ Viral DNA $\to$ Host DNA $\to$ Host RNA $\to$ Protein

After the HIV binds to the CD4 receptor on the host cell it releases its RNA into the host cell and the following process begins-

1) Reverse Transcription- The single-stranded HIV RNA is transcribed to double-stranded DNA.

2) Integration- This newly formed double-stranded HIV DNA enters the host cell nucleus. The HIV enzyme integrase binds the HIV DNA to the host DNA and this integrated HIV DNA is now called provirus.

3)Transcription- When the host cell receives an activation signal the provirus uses host enzyme RNA polymerase to create new copies of the HIV genomic material and short strands of RNA called messenger RNA.

4) Assembly- HIV enzyme protease cleaves the long chains of HIV proteins into smaller individual proteins that combine with copies of HIV RNA genetic material and a new virus particle is assembled.

Thus the correct answer is option B.