title: Phase variable DNA repeats inNeisseria gonorrhoeaeinfluence transcription, translation, and protein sequence variation.
abstract: There are many types of repeated DNA sequences in the genomes of the species of the genusNeisseria, from homopolymeric tracts to tandem repeats of hundreds of bases. Some of these have roles in the phase-variable expression of genes. When a repeat mediates phase variation, reversible switching between tract lengths occurs, which in the species of the genusNeisseriamost often causes the gene to switch between on and off states through frame shifting of the open reading frame. Changes in repeat tract lengths may also influence the strength of transcription from a promoter. For phenotypes that can be readily observed, such as expression of the surface-expressed Opa proteins or pili, verification that repeats are mediating phase variation is relatively straightforward. For other genes, particularly those where the function has not been identified, gathering evidence of repeat tract changes can be more difficult. Here we present analysis of the repetitive sequences that could mediate phase variation in theNeisseria gonorrhoeaestrain NCCP11945 genome sequence and compare these results with other gonococcal genome sequences. Evidence is presented for an updated phase-variable gene repertoire in this species, including a class of phase variation that causes amino acid changes at theC-terminus of the protein, not previously described inN. gonorrhoeae.
authors.affiliation: 1​School of Life Sciences, Pharmacy, and Chemistry, Kingston University, Penrhyn Road, Kingston upon Thames, UK.
authors.forename: Marta A
authors.initials: MA
authors.lastname: Zelewska
authors.affiliation: 1​School of Life Sciences, Pharmacy, and Chemistry, Kingston University, Penrhyn Road, Kingston upon Thames, UK.
authors.forename: Madhuri
authors.initials: M
authors.lastname: Pulijala
authors.affiliation: 1​School of Life Sciences, Pharmacy, and Chemistry, Kingston University, Penrhyn Road, Kingston upon Thames, UK.
authors.forename: Russell
authors.initials: R
authors.lastname: Spencer-Smith
authors.affiliation: 1​School of Life Sciences, Pharmacy, and Chemistry, Kingston University, Penrhyn Road, Kingston upon Thames, UK.
authors.forename: Hiba-Tun-Noor A
authors.initials: HA
authors.lastname: Mahmood
authors.affiliation: 1​School of Life Sciences, Pharmacy, and Chemistry, Kingston University, Penrhyn Road, Kingston upon Thames, UK.
authors.forename: Billie
authors.initials: B
authors.lastname: Norman
authors.affiliation: 1​School of Life Sciences, Pharmacy, and Chemistry, Kingston University, Penrhyn Road, Kingston upon Thames, UK.
authors.forename: Colin P
authors.initials: CP
authors.lastname: Churchward
authors.affiliation: 1​School of Life Sciences, Pharmacy, and Chemistry, Kingston University, Penrhyn Road, Kingston upon Thames, UK.
authors.forename: Alan
authors.initials: A
authors.lastname: Calder
authors.affiliation: 1​School of Life Sciences, Pharmacy, and Chemistry, Kingston University, Penrhyn Road, Kingston upon Thames, UK.
authors.forename: Lori A S
authors.initials: LAS
authors.lastname: Snyder
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial / Q000235:genetics*; D014644:Genetic Variation / Q000235:genetics; D009344:Neisseria gonorrhoeae / Q000235:genetics*; D012091:Repetitive Sequences, Nucleic Acid / Q000235:genetics*
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial
keywords: C-terminal variation; gonococcus; homopolymeric tract; phase variation; simple sequence repeats