Which of the following correctly lists the major steps in HIV retroviral replication in order?

• A. Reverse Transcription, Integration, Attachment, Fusion, Assembly, Release
• B. Attachment, Translation, Integration, Reverse Transcription, Assembly, Release
• C. Fusion, Attachment, Transcription, Translation, Assembly, Release
• D. Attachment, Fusion, Reverse Transcription, Integration, Transcription, Translation, Assembly, Release

Answer: (D)

Verified step by step guidance

1. Step 1: Understand the HIV retroviral replication cycle begins with the virus attaching to the host cell. This is called Attachment, where the viral envelope glycoproteins bind to specific receptors on the host cell surface.
2. Step 2: After attachment, the virus undergoes Fusion, where the viral envelope fuses with the host cell membrane, allowing the viral capsid to enter the cytoplasm.
3. Step 3: Once inside, Reverse Transcription occurs. The viral RNA genome is reverse transcribed into complementary DNA (cDNA) by the viral enzyme reverse transcriptase.
4. Step 4: The newly synthesized viral DNA is then integrated into the host cell genome in a process called Integration, mediated by the viral integrase enzyme.
5. Step 5: Following integration, the viral DNA is transcribed into RNA (Transcription), which is then translated into viral proteins (Translation). These components are assembled into new viral particles (Assembly), which are finally released from the host cell (Release) to infect new cells.