From The HIV replication cycle a web-based interactive account
An IN tetramer bound to DNA. The IN protein studied was from prototype foamy virus (PFV). From coordinate file 3OS0.
The resulting viral DNA remains associated with a subset of the viral proteins, including the integrase protein, in the preintegration complex. The viral integrase protein carries out the initial DNA breaking and joining reactions mediating integration 
- ↑ Bushman FD, Fujiwara T, Craigie R. 1990. Retroviral DNA integration directed by HIV integration protein in vitro. Science 249: 1555-1558..