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

PLoS One. 2013;8(1):e53572. doi: 10.1371/journal.pone.0053572. Epub 2013 Jan 14.

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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • DNA, Circular / metabolism
  • DNA, Viral / chemistry*
  • DNA, Viral / isolation & purification*
  • DNA, Viral / metabolism
  • Dialysis
  • Electrophoresis
  • HIV Integrase / isolation & purification*
  • HIV Integrase / metabolism
  • Humans
  • Microscopy, Atomic Force / methods*
  • Molecular Weight
  • Nucleic Acid Conformation*
  • Protein Binding
  • Protein Multimerization*
  • Recombinant Proteins / metabolism*
  • Repetitive Sequences, Nucleic Acid

Substances

  • DNA, Circular
  • DNA, Viral
  • Recombinant Proteins
  • HIV Integrase
  • p31 integrase protein, Human immunodeficiency virus 1

Grants and funding

This work was supported by a Grant-in-Aid for Cancer Research from the Ministry of Education, Culture, Science and Technology, Japan, and by a grant from the Ministry of Health, Welfare, and Labor, Japan. The funding agencies had no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript.