It’s a multi stage process. Each step is crucial for it’s understanding.
Step 1. is the infection of a suitable host cell.
Entry of the virus requires of the presence of certain receptors on the cell surface. CD4 receptors and coal / core receptors such as CCR5 or CXCR4. These receptors interact with protein complexes which are embedded in the viral envelope.
These complexes are composed of two glycoproteins and extra cellular GP120 and a trans membrane GP41.When the virus approaches the target cell GP120 binds to the CD4 receptors. This process is termed “attachment”.
It promotes further binding to a coal receptor.
Coal / core receptor binding results in a conformational change in GP120. This allows GP41 to unfold and insert it’s hydrophobic terminus into the cell membrane. GP41 than folds back on itself.
This draws the virus towards the cell and facilitates the fusion of their membranes. The viral nucleo capsid enters the host cell and breaks open releasing two viral arenal/arenal strands and three essential replication enzymes. Integrease and protease and reversed transcriptease.
Reversed transcriptease is begins the reversed transcription of viral RNA. It has two catalytic domains. The rivonuclease H active site and the polimerease active site.
Here single stranded viral RNA is transcribed into a RNA-DNA double helix. Rivonuclease H breaks down the RNA. The polimerease then completes the DNA strand to form a DNA double helix.
Now integrease goes into action.
It cuts a dynoleotyde from each prime end of the DNA creating two sticky ends. Integrease then transfers the DNA into the cell nucleus and facilitates the integration into the host cell genome.
The host cell genome now contains the genetic information of the virus.
Activation of the cell induces transcription of pro viral DNA into messenger RNA. The viral messenger RNA migrates into the cytoplasm where building blocks for a new virus is synthesized.
Some of them have to be processed by the viral protease. Protease cuts longer proteins into smaller core proteins. This step is crucial to create an infectious virus. Two viral RNA straps and the replication enzymes then come together and core proteins assemble around them forming the capsid (aka protein coat, shell of a virus) This immature viral particle leaves the cell acquiring a new envelop of host and viral proteins.
The virus matures and becomes ready to infect other cells.
A virus can replicates billions of times a day to destroy to host immune cells and eventually causing disease progression. Information which interferes with the key steps of viral replication can stop this fatal process.
Entry into to host cell can be blocked by information.
The action of integrease can be blocked.