title: Identification of an evolutionarily conserved domain in human lens epithelium-derived growth factor/transcriptional co-activator p75 (LEDGF/p75) that binds HIV-1 integrase.
abstract: Human lens epithelium-derived growth factor/transcriptional co-activator p75 (LEDGF/p75) protein was recently identified as a binding partner for HIV-1 integrase (IN) in human cells. In this work, we used biochemical and bioinformatic approaches to define the domain organization of LEDGF/p75. Using limited proteolysis and deletion mutagenesis we show that the protein contains a pair of evolutionarily conserved domains, assuming about 35% of its sequence. Whereas the N-terminal PWWP domain had been recognized previously, the second domain is novel. It is comprised of approximately 80 amino acid residues and is both necessary and sufficient for binding to HIV-1 IN. Strikingly, the integrase binding domain (IBD) is not unique to LEDGF/p75, as a second human protein, hepatoma-derived growth factor-related protein 2 (HRP2), contains a homologous sequence. LEDGF/p75 and HRP2 IBDs avidly bound HIV-1 IN in an in vitro GST pull-down assay and each full-length protein potently stimulated HIV-1 IN activity in vitro. LEDGF/p75 and HRP2 are predicted to share a similar domain organization and have an evident evolutionary and likely functional relationship.
authors.affiliation: Departments of Cancer Immunology and AIDS and Cancer Biology, Dana-Farber Cancer Institute, Boston, Massachusetts 02115, USA.
authors.forename: Peter
authors.initials: P
authors.lastname: Cherepanov
authors.forename: Eric
authors.initials: E
authors.lastname: Devroe
authors.forename: Pamela A
authors.initials: PA
authors.lastname: Silver
authors.forename: Alan
authors.initials: A
authors.lastname: Engelman
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002460:Cell Line; D003001:Cloning, Molecular; D019295:Computational Biology; D017124:Conserved Sequence; D004247:DNA / Q000737:chemistry; D018076:DNA, Complementary / Q000378:metabolism; D019143:Evolution, Molecular; D017353:Gene Deletion; D005978:Glutathione / Q000378:metabolism; D005982:Glutathione Transferase / Q000378:metabolism; D019427:HIV Integrase / Q000378:metabolism*; D006801:Humans; D047468:Immunoprecipitation; D036341:Intercellular Signaling Peptides and Proteins / Q000737:chemistry* / Q000378:metabolism; D007908:Lens, Crystalline / Q000378:metabolism*; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D011485:Protein Binding; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D011994:Recombinant Proteins / Q000737:chemistry; D017386:Sequence Homology, Amino Acid; D013696:Temperature; D014162:Transfection
chemical_list: D018076:DNA, Complementary; D036341:Intercellular Signaling Peptides and Proteins; D011994:Recombinant Proteins; C051610:hepatoma-derived growth factor; C119380:lens epithelium-derived growth factor; D004247:DNA; D005982:Glutathione Transferase; D019427:HIV Integrase; D005978:Glutathione