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Cloning, purification and structure determination of the HIV integrase-binding domain of lens epithelium-derived growth factor.

ABSTRACT: Lens epithelium-derived growth factor (LEDGF)/p75 is the dominant binding partner of HIV-1 integrase in human cells. The crystal structure of the HIV integrase-binding domain (IBD) of LEDGF has been determined in the absence of ligand. IBD was overexpressed in Escherichia coli, purified and crystallized by sitting-drop vapour diffusion. X-ray diffraction data were collected at Diamond Light Source to a resolution of 2.05?Å. The crystals belonged to space group P2₁, with eight polypeptide chains in the asymmetric unit arranged as an unusual octamer composed of four domain-swapped IBD dimers. IBD exists as a mixture of monomers and dimers in concentrated solutions, but the dimers are unlikely to be biologically relevant.

SUBMITTER: Hannon C

PROVIDER: S-EPMC5947699 | biostudies-literature | 2018 Mar

REPOSITORIES: biostudies-literature

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Cloning, purification and structure determination of the HIV integrase-binding domain of lens epithelium-derived growth factor.

Hannon Clare C Cruz-Migoni Abimael A Platonova Olga O Owen Robin L RL Nettleship Joanne E JE Miller Ami A Carr Stephen B SB Harris Gemma G Rabbitts Terence H TH Phillips Simon E V SEV

Acta crystallographica. Section F, Structural biology communications 20180226 Pt 3

Lens epithelium-derived growth factor (LEDGF)/p75 is the dominant binding partner of HIV-1 integrase in human cells. The crystal structure of the HIV integrase-binding domain (IBD) of LEDGF has been determined in the absence of ligand. IBD was overexpressed in Escherichia coli, purified and crystallized by sitting-drop vapour diffusion. X-ray diffraction data were collected at Diamond Light Source to a resolution of 2.05 Å. The crystals belonged to space group P2<sub>1</sub>, with eight polypept ...[more]

PMID: 29497017

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Structural properties of HIV integrase. Lens epithelium-derived growth factor oligomers.

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The same site on the integrase-binding domain of lens epithelium-derived growth factor is a therapeutic target for MLL leukemia and HIV.

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Lens epithelium-derived growth factor/p75 interacts with the transposase-derived DDE domain of PogZ.

Project description:Lens epithelium-derived growth factor/p75 (LEDGF/p75) is a prominent cellular interaction partner of human immunodeficiency virus-1 (HIV-1) integrase, tethering the preintegration complex to the host chromosome. In light of the development of LEDGF/p75-integrase interaction inhibitors, it is essential to understand the cell biology of LEDGF/p75. We identified pogZ as new cellular interaction partner of LEDGF/p75. Analogous to lentiviral integrase, pogZ, a domesticated transposase, carries a DDE domain, the major determinant for LEDGF/p75 interaction. Using different in vitro and in vivo approaches, we corroborated the interaction between the C terminus of LEDGF/p75 and the DDE domain of pogZ, revealing an overlap in the binding of pogZ and HIV-1 integrase. Competition experiments showed that integrase is efficient in displacing pogZ from LEDGF/p75. Moreover, pogZ does not seem to play a role as a restriction factor of HIV. The finding that LEDGF/p75 is capable of interacting with a DDE domain protein that is not a lentiviral integrase points to a profound role of LEDGF/p75 in DDE domain protein function.

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A Peptide Derived from Lens Epithelium-Derived Growth Factor Stimulates HIV-1 DNA Integration and Facilitates Intasome Structural Studies.

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Dialysis purification of integrase-DNA complexes provides high-resolution atomic force microscopy images: dimeric recombinant HIV-1 integrase binding and specific looping on DNA.

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| S-EPMC3544922 | biostudies-literature

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