Nucleic Acids Research Advance Access originally published online on November 5, 2008
Nucleic Acids Research 2008 36(22):7043-7058; doi:10.1093/nar/gkn796
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Nucleic Acids Research, 2008, Vol. 36, No. 22 7043-7058
© 2008 The Author(s)
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/2.0/uk/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
Nucleic Acid Enzymes |
In vitro initial attachment of HIV-1 integrase to viral ends: control of the DNA specific interaction by the oligomerization state
1Laboratoire MCMP, UMR 5234-CNRS, 2Université Victor Segalen Bordeaux 2, 3IFR 66 "Pathologies Infectieuses et Cancers", Bordeaux, France and 4Institute of Chemical Biology and Fundamental Medicine, Siberian Division of Russian Academy of Sciences, Lavrentyeva Ave. 8, 630090, Russia
*To whom correspondence should be addressed. Tel: +33 557 57 17 40; Fax: +33 557 57 17 66; Email: vincent.parissi{at}reger.u-bordeaux2.fr
Received August 7, 2008. Revised October 10, 2008. Accepted October 10, 2008.
HIV-1 integrase (IN) oligomerization and DNA recognition are crucial steps for the subsequent events of the integration reaction. Recent advances described the involvement of stable intermediary complexes including dimers and tetramers in the in vitro integration processes, but the initial attachment events and IN positioning on viral ends are not clearly understood. In order to determine the role of the different IN oligomeric complexes in these early steps, we performed in vitro functional analysis comparing IN preparations having different oligomerization properties. We demonstrate that in vitro IN concerted integration activity on a long DNA substrate containing both specific viral and nonspecific DNA sequences is highly dependent on binding of preformed dimers to viral ends. In addition, we show that IN monomers bound to nonspecific DNA can also fold into functionally different oligomeric complexes displaying nonspecific double-strand DNA break activity in contrast to the well known single strand cut catalyzed by associated IN. Our results imply that the efficient formation of the active integration complex highly requires the early correct positioning of monomeric integrase or the direct binding of preformed dimers on the viral ends. Taken together the data indicates that IN oligomerization controls both the enzyme specificity and activity.