Properties of human immunodeficiency virus type 1 reverse transcriptase recombination upon infection.

Reverse transcription (RT) is one of the hallmark features of retroviruses. During RT, virus encoded reverse transcriptase (RTase) must transfer from one end to the other end of the viral genome on two separate occasions to complete RT and move on to the production of proviral DNA. In addition, multiple strand-transfer events between homologous regions of the dimerized viral genome by RTase are also observed, and such recombination events serve as one of the driving forces behind human immunodeficiency virus (HIV) genome sequence diversity. Although retroviral recombination is widely considered to be important, several features of its mechanism are still unclear. We constructed an HIV-1 vector system to examine the target sequences required for virus recombination, and elucidated other necessary prerequisites to harbor recombination, such as the length, homology and the stability of neighbouring structures around the target sequences.