HIV is a retrovirus, which means that it cannot replicate on its own. Instead, it replicates by infecting other cells.
Click on a component in the diagram below for more information on the components of the HIV virion.
Envelope protein
The envelope protein is found on the surface of the virus particle. It has two parts: gp120 and gp41. gp120 is the cap-like structure found outside the virus particle; it is the first part to make contact with receptors on the target cell. gp41 spans the viral membrane, anchors the gp120 in place, and causes the fusion of virus and cell membranes during the entry stage of infection.
Viral membrane
A thin layer of fatty material that encloses the contents of the virus particle.
Viral RNA
The genetic material that contains information that codes for all the viral proteins. Two copies of the viral RNA are included in each viral particle.
Nucleocapsid
A protein found within the capsid that coats the viral RNA.
Capsid
The cone-shaped core of the virus, which consists of the protein p24. The capsid contains the genetic information and enzymes needed for the virus to replicate.
Matrix
A layer, beneath the viral membrane, that consists of the protein p17.
Integrase
An enzyme found within the capsid that causes the viral DNA to integrate, or insert, into the DNA of the host cell.
Reverse Transcriptase
An enzyme found within the capsid that is needed to make viral DNA by copying the sequence of the viral RNA.
Protease
An enzyme that cuts long strands of HIV protein into the smaller components, that make up the mature virus particle.
p6
A small viral protein that recruits host cell proteins that pinch off the viral bud.
