In vitro human immunodeficiency virus type 1 integrase assays.

Publisher Summary This chapter describes in vitro integration assays, which are used to elucidate the enzyme mechanisms and to discover, design, and develop integrase inhibitors. Integration of the human immunodeficiency virus type 1 (HIV- 1) genome into host cell DNA is an essential step for viral replication. Soon after cell penetration, the single-stranded viral RNA is reverse transcribed into a double-stranded proviral DNA. The next major event is integration, whereby the viral DNA is inserted into the host chromosome to create the proviral state. This event is catalyzed by a viral enzyme called integrase, encoded in the pol gene and generated after proteolysis of the Gag–Pol fusion protein precursor by the HIV-1 protease. In HIV-l-infected patients, at present, only reverse transcriptase and protease inhibitors are used as a combination in highly active antiretroviral therapy (HAART). Because HIV-1 integrase is absolutely required for viral replication and because it has no cellular equivalent, this enzyme is an excellent target for a chemotherapeutic approach.