title: Structural basis for the recognition between HIV-1 integrase and transcriptional coactivator p75.
abstract: Integrase (IN) is an essential retroviral enzyme, and human transcriptional coactivator p75, which is also referred to as lens epithelium-derived growth factor (LEDGF), is the dominant cellular binding partner of HIV-1 IN. Here, we report the crystal structure of the dimeric catalytic core domain of HIV-1 IN complexed to the IN-binding domain of LEDGF. Previously identified LEDGF hotspot residues anchor the protein to both monomers at the IN dimer interface. The principal structural features of IN that are recognized by the host factor are the backbone conformation of residues 168-171 from one monomer and a hydrophobic patch that is primarily comprised of alpha-helices 1 and 3 of the second IN monomer. Inspection of diverse retroviral primary and secondary sequence elements helps to explain the apparent lentiviral tropism of the LEDGF-IN interaction. Because the lethal phenotypes of HIV-1 mutant viruses unable to interact with LEDGF indicate that IN function is highly sensitive to perturbations of the structure around the LEDGF-binding site, we propose that small molecule inhibitors of the protein-protein interaction might similarly disrupt HIV-1 replication.
authors.affiliation: Department of Cancer Immunology and AIDS, Dana-Farber Cancer Institute, Boston, MA 02115, USA. alan_engelman@dfci.harvard.edu
authors.forename: Peter
authors.initials: P
authors.lastname: Cherepanov
authors.forename: Andre L B
authors.initials: AL
authors.lastname: Ambrosio
authors.forename: Shaila
authors.initials: S
authors.lastname: Rahman
authors.forename: Tom
authors.initials: T
authors.lastname: Ellenberger
authors.forename: Alan
authors.initials: A
authors.lastname: Engelman
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000737:chemistry* / Q000378:metabolism*; D003460:Crystallization; D019427:HIV Integrase / Q000737:chemistry* / Q000378:metabolism*; D006801:Humans; D008958:Models, Molecular; D011485:Protein Binding; D011487:Protein Conformation; D014157:Transcription Factors / Q000737:chemistry* / Q000378:metabolism*
chemical_list: D048868:Adaptor Proteins, Signal Transducing; C504649:PSIP1 protein, human; D014157:Transcription Factors; D019427:HIV Integrase