Integration of Viral DNA

HIV DNA IntegrationOnce the viral RNA has been reverse-transcribed into a strand of DNA, the DNA can then be integrated (inserted) into the DNA of the lymphocyte. The virus has its own enzyme called "integrase" that facilitates incorporation of the viral DNA into the host cells DNA. The integrated DNA is called a provirus.

 

Transcription: Back to RNA

HIV TranscriptionAs long as the lymphocyte is not activated or "turned-on", nothing happens to the viral DNA. But if the lymphocyte is activated, transcription of the viral DNA begins, resulting in the production of multiple copies of viral RNA. This RNA codes for the production of the viral proteins and enzymes (translation) and will also be packaged later as new viruses.

 

Translation: RNA >>> Proteins

HIV Translation of RNAThere are only 9 genes in the HIV RNA. Those genes have the code necessary to produce structural proteins such as those that are incorporated into the viral envelope and core plus enzymes like reverse transcriptase, integrase, and a crucial enzyme called a protease.

 

HIV Sequence of Infection

1. ATTACHMENT
Getting in

2. REVERSE TRANSCRIPTION 
From viral RNA to DNA

3. INTEGRATION, TRANSCRIPTION 
a. Viral DNA joins host DNA
b. Making multiple viral RNAs

4. TRANSLATION 
Producing viral proteins

5. VIRAL PROTEASE 
Cleaving viral proteins

6. ASSEMBLY & BUDDING 
Getting out