Visualisation of human Rad52 protein and its complexes with hRad51 and DNA

Eric Van Dyck, Nasser M.A. Hajibagheri, Andrzej Stasiak, Stephen C. West*

*Corresponding author for this work

Research output: Contribution to journalArticleResearchpeer-review

91 Citations (Scopus)

Abstract

The human Rad52 protein stimulates joint molecule formation by kRad51, a homologue of Escherichia coli RecA protein. Electron microscopic analysis of hRad52 shows that it self-associates to form ring structures with a diameter of approximately 10 nm. Each ring contains a hole at its centre. hRad52 binds to single and double-stranded DNA. In the ssDNA-hRad52 complexes, hRad52 was distributed along the length of the DNA, which exhibited a characteristic 'beads on a string' appearance. At higher concentrations of hRad52, 'super-rings' (approximately 30 nm) were observed and the ssDNA was collapsed upon itself. In contrast, in dsDNA-hRad52 complexes, some regions of the DNA remained protein-free while others, containing hRad52, interacted to form large protein-DNA networks. Saturating concentrations of hRad51 displaced hRad52 from ssDNA, whereas dsDNA-Rad52 complexes (networks) were more resistant to hRad51 invasion and nucleoprotein filament formation. When Rad52-Rad51-DNA complexes were probed with gold-conjugated hRad52 antibodies, the presence of globular hRad52 structures within the Rad51 nucleoprotein filament was observed. These data provide the first direct visualisation of protein-DNA complexes formed by the human Rad51 and Rad52 recombination/repair proteins.

Original languageEnglish
Pages (from-to)1027-1038
Number of pages12
JournalJournal of Molecular Biology
Volume284
Issue number4
DOIs
Publication statusPublished - 11 Dec 1998
Externally publishedYes

Keywords

  • DNA repair
  • Electron microscopy
  • Genetic recombination
  • Protein-DNA interactions
  • Ring proteins

Fingerprint

Dive into the research topics of 'Visualisation of human Rad52 protein and its complexes with hRad51 and DNA'. Together they form a unique fingerprint.

Cite this