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An alternative DNA structure is necessary for pilin antigenic variation in Neisseria gonorrhoeae.

ABSTRACT: Pathogens can use DNA recombination to promote antigenic variation (Av) of surface structures to avoid immune detection. We identified a cis-acting DNA sequence near the antigenically variable pilin locus of the human pathogen, Neisseria gonorrhoeae. This 16-base pair guanine (G)-rich sequence was required for pilin Av and formed a guanine quartet (G4) structure in vitro. Individual mutations that disrupted the structure also blocked pilin Av and prevented nicks required for recombination from occurring within the G4 region. A compound that binds and stabilizes G4 structures also inhibited pilin Av and prevented nicks from occurring on the G-rich strand. This site constitutes a recombination initiation sequence/structure that directs gene conversion to a specific chromosomal locus.

SUBMITTER: Cahoon LA

PROVIDER: S-EPMC2803317 | biostudies-literature | 2009 Aug

REPOSITORIES: biostudies-literature

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An alternative DNA structure is necessary for pilin antigenic variation in Neisseria gonorrhoeae.

Cahoon Laty A LA Seifert H Steven HS

Science (New York, N.Y.) 20090801 5941

Pathogens can use DNA recombination to promote antigenic variation (Av) of surface structures to avoid immune detection. We identified a cis-acting DNA sequence near the antigenically variable pilin locus of the human pathogen, Neisseria gonorrhoeae. This 16-base pair guanine (G)-rich sequence was required for pilin Av and formed a guanine quartet (G4) structure in vitro. Individual mutations that disrupted the structure also blocked pilin Av and prevented nicks required for recombination from o ...[more]

PMID: 19661435

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