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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.

ABSTRACT: It remains difficult to obtain high-resolution atomic force microscopy images of HIV-1 integrase bound to DNA in a dimeric or tetrameric fashion. We therefore constructed specific target DNAs to assess HIV-1 integrase binding and purified the complex by dialysis prior to analysis. Our resulting atomic force microscopy analyses indicated precise size of binding human immunodeficiency virus type 1 (HIV-1) recombinant integrase in a tetrameric manner, inducing formation of a loop-like or figure-eight-like secondary structure in the target DNA. Our findings regarding the target DNA secondary structure provide new insights into the intermediate states of retroviral integration.

SUBMITTER: Tsuruyama T

PROVIDER: S-EPMC3544922 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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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.

Tsuruyama Tatsuaki T Nakai Tonau T Ohmori Rei R Ozeki Munetaka M Tamaki Keiji K Yoshikawa Kenichi K

PloS one 20130114 1

It remains difficult to obtain high-resolution atomic force microscopy images of HIV-1 integrase bound to DNA in a dimeric or tetrameric fashion. We therefore constructed specific target DNAs to assess HIV-1 integrase binding and purified the complex by dialysis prior to analysis. Our resulting atomic force microscopy analyses indicated precise size of binding human immunodeficiency virus type 1 (HIV-1) recombinant integrase in a tetrameric manner, inducing formation of a loop-like or figure-eig ...[more]

PMID: 23341952

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