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Updated: May 17, 2026
05:32
In Vitro Chemical Mapping of G-Quadruplex DNA Structures by Bis-3-Chloropiperidines
Published on: May 12, 2023
RecA-binding pilE G4 sequence essential for pilin antigenic variation forms monomeric and 5' end-stacked dimeric
Vitaly Kuryavyi1, Laty A Cahoon, H Steven Seifert
1Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, NY, 10065, USA. v.kuryavyi@gmail.com
Structure (London, England : 1993)
|October 23, 2012
Summary
Neisseria gonorrhoeae uses G-quadruplex sequences near the pilE gene for antigenic variation. These G-quadruplex structures interact with RecA protein, facilitating DNA recombination for immune evasion.
Area of Science:
- Microbiology
- Molecular Biology
- Structural Biology
Background:
- Neisseria gonorrhoeae evades immune surveillance via antigenic variation of pili.
- A G-quadruplex (G4) sequence upstream of the pilE locus is crucial for initiating this variation.
Purpose of the Study:
- To determine the structures of pilE G-quadruplexes.
- To investigate the interaction between pilE G-quadruplexes and RecA protein.
Main Methods:
- NMR spectroscopy to determine G-quadruplex structures.
- In vitro RecA-mediated strand exchange assays.
Main Results:
- Structures of all-parallel stranded monomeric and dimeric pilE G-quadruplexes were determined.
- The monomeric pilE G-quadruplex binds RecA and promotes strand exchange.
- RecA-G4 interactions were modeled within the RecA DNA-binding site.
Conclusions:
- The monomeric pilE G-quadruplex structure is compatible with RecA binding.
- Interactions between RecA and the pilE G-quadruplex likely facilitate pilin diversification.
- This mechanism contributes to Neisseria gonorrhoeae's immune evasion strategies.
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