Figure 1. Schematic of HIV entering the nucleus.

The genetic material of HIV is surrounded by a capsid (grey honeycomb structure). Previously, it was thought that the virus sheds this capsid before it enters the nucleus. Bejarano et al. now show that, in macrophages, the virus retains its capsid while entering the nucleus, through the nuclear pore complex (NPC; turquoise), Two proteins, CPSF6 (blue circle), and Nup153 (lilac oval) control this process. First, Nup153 binds to the capsid as it associates with the pore complex. CPSF6 then binds to the same region of the capsid, displacing the Nup153, and helping the capsid enter the nucleus. Finally, the capsid ‘uncoats’ and the viral DNA integrates into the host DNA with the help of an enzyme called integrase (green oval) and a protein called LEDGF (purple oval).