Chapter 18, Problem 36A

Summary Introduction

To determine:

The sequence of event of replication of HIV in one sentence.

Introduction:

HIV (human immunodeficiency virus) and AIDS (acquired immune deficiency syndrome) is a viral infection that is either acquired or congenital. Acquired HIV/AIDS occurs through contact with the blood, semen, vaginal secretions, breast milk, and amniotic fluid of carriers.

Explanation of Solution

The HIV uses the T helper cells or the CD 4 cells as host cell to replicate. The HIV replication cycle consist of 7 steps given below:

1. Attachment: At this step, the virus is attached to the membrane of the helper T cells.
2. Fusion: At this step, the envelop of the HIV virus enters the host cells. The fusion of the HIV envelope and cell membrane of the host cell causes the entry of the viral genome.
3. Reverse transcription: As the HIV is an RNA virus, it produces reverse transcriptase to convert HIV RNA to HIV DNA.
4. Integration: At this step, the integration of HIV DNA takes place to the DNA of the CD4 cells with help of integrase.
5. Replication: As the HIV genome is integrate, HIV replicates itself and makes viral protein, which act as building block of more HIV.
6. Assembly: The HIV protein and HIV RNA get assembled in the cell and forms immature HIV.
7. Budding: The immature HIV gets out of the cells and release protease. This protease breaks up long protein chain and the smaller fragments of the protein forms multiple new HIV.