After entering a cell, the HIV particle must make its way to the nucleus to unload the viral genome without triggering cellular defense mechanisms.
The extent to which the viral capsid remains intact after entering the cell is currently debated within the scientific community. This animation shows a model in which the capsid remains largely intact while it is transported to the nucleus. Inside the capsid, and soon after cellular entry, reverse transcriptase starts to create a DNA copy of the viral RNA genome. By the time it reaches the nuclear pore, a complete DNA copy of the viral genome has been made, and a significant portion of the capsid coat has been lost.
The viral DNA, now bound to the viral enzyme integrase, enters the nucleus through the nuclear pore. Inside the nucleus, the viral DNA integrates with the host genome.
PDBs used in this animation:
Many thanks to Alan Engelman (Harvard Medical School & Dana-Farber Cancer Institute) for helpful conversations and advice.