FRET analysis reveals distinct conformations of IN tetramers in the presence of viral DNA or LEDGF/p75.

ABSTRACT: A tetramer of HIV-1 integrase (IN) stably associates with the viral DNA ends to form a fully functional concerted integration intermediate. LEDGF/p75, a key cellular binding partner of the lentiviral enzyme, also stabilizes a tetrameric form of IN. However, functional assays have indicated the importance of the order of viral DNA and LEDGF/p75 addition to IN for productive concerted integration. Here, we employed Förster Resonance Energy Transfer (FRET) to monitor assembly of individual IN subunits into tetramers in the presence of viral DNA and LEDGF/p75. The IN-viral DNA and IN-LEDGF/p75 complexes yielded significantly different FRET values suggesting two distinct IN conformations in these complexes. Furthermore, the order of addition experiments indicated that FRET for the preformed IN-

SUBMITTER: Kessl JJ 

PROVIDER: S-EPMC3203615 | biostudies-literature | 2011 Nov

REPOSITORIES: biostudies-literature