Volume 6 Supplement 2

Frontiers of Retrovirology: Complex retroviruses, retroelements and their hosts

Open Access

Structural basis for HIV-1 DNA integration in the human genome

  • Fabrice Michel1,
  • Sylvia Eiler1,
  • Florence Granger1,
  • Jean-François Mouscadet2,
  • Marina Gottikh3,
  • Alexis Nazabal4,
  • Stéphane Emiliani5,
  • Richard Benarous6,
  • Dino Moras1,
  • Patrick Schultz1 and
  • Marc Ruff1
Retrovirology20096(Suppl 2):P79

https://doi.org/10.1186/1742-4690-6-S2-P79

Published: 24 September 2009

Integration of the human immunodeficiency virus type 1 (HIV-1) cDNA into the human genome is catalyzed by the viral integrase protein that requires the lens epithelium-derived growth factor (LEDGF), a cellular transcriptional coactivator. In the presence of LEDGF, integrase forms a stable complex in vitro and importantly becomes soluble by contrast with integrase alone which aggregates and precipitates. Using cryo-electron microscopy (EM) and single-particle reconstruction, we obtained three-dimensional structures of the wild type full length integrase-LEDGF complex with and without DNA [1]. The stoichiometry of the complex was found to be (integrase)4-(LEDGF)2 by mass spectrometry analysis and existing atomic structures were unambiguous positioned in the EM map. In vitro functional assays reveal that LEDGF increases integrase activity likely in maintaining a stable and functional integrase structure. DNA-Protein cross-linking experiments show specific interaction between viral DNA and the C-terminal domain of integrase. Upon DNA binding, IN undergoes large conformational changes. Cryo-EM structure underlines the path of viral and target DNA and a model for DNA integration in human DNA is proposed (see fig. 1, overleaf).
Figure 1

Proposed mechanism for thei ntegration of viral cDNA into the host genome: The LEDGF envelope is represented in blue; the integrase tetramer is shown as atomic structures. The viral DNA is in orange and the target DNA in red. On target DNA binding, there is a conformational change of the integrase proteins to position the viral DNA for the integration within 5 bases pairs in the target DNA.

Authors’ Affiliations

(1)
IGBMC, UDS, U596 Inserm, UMR7104 CNRS
(2)
Laboratoire de Biotechnologie et Pharmacologie Génétique Appliquée, CNRS, UMR8113, ENS-Cachan
(3)
Belozersky Institute of Physico-Chemical Biology, Moscow State University
(4)
CovalX, Technoparkstrasse, 1
(5)
Institut Cochin, Université Paris Descartes, CNRS (UMR8104), Inserm, U567
(6)
CellVir SAS, Evry, France; Hybrigenics SA

References

  1. Michel F, Crucifix C, Granger F, Eiler S, Mouscadet JF, Korolev S, Agapkina J, Ziganshin R, Gottikh M, Nazabal A, Emiliani S, Benarous R, Moras D, Schultz P, Ruff M: Structural basis for HIV-1 DNA integration in the human genome, role of the LEDGF/P75 cofactor. EMBO J. 2009, 28: 980-991. 10.1038/emboj.2009.41.PubMed CentralView ArticlePubMedGoogle Scholar

Copyright

© Michel et al; licensee BioMed Central Ltd. 2009

This article is published under license to BioMed Central Ltd.

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