H-NS suppresses pilE intragenic transcription and antigenic variation in Neisseria gonorrhoeae
Masters, Thao L. and Wachter, Shaun and Wachter, Jenny and Hill, Stuart A.,, 162, 177-190 (2016),
doi = https://doi.org/10.1099/mic.0.000199,
publicationName = Microbiology Society,
issn = 1350-0872,
abstract= Initially, pilE transcription in Neisseria gonorrhoeae appeared to be complicated, yet it was eventually simplified into a model where integration host factor activates a single − 35/ − 10 promoter. However, with the advent of high-throughput RNA sequencing, numerous small pil-specific RNAs (sense as well as antisense) have been identified at the pilE locus as well as at various pilS loci. Using a combination of in vitro transcription, site-directed mutagenesis, Northern analysis and quantitative reverse transcriptase PCR (qRT-PCR) analysis, we have identified three additional non-canonical promoter elements within the pilE gene; two are located within the midgene region (one sense and one antisense), with the third, an antisense promoter, located immediately downstream of the pilE ORF. Using strand-specific qRT-PCR analysis, an inverse correlation exists between the level of antisense expression and the amount of sense message. By their nature, promoter sequences tend to be AT-rich. In Escherichia coli, the small DNA-binding protein H-NS binds to AT-rich sequences and inhibits intragenic transcription. In N. gonorrhoeae hns mutants, pilE antisense transcription was increased twofold, with a concomitant decrease in sense transcript levels. However, most noticeably in these mutants, the absence of H-NS protein caused pilE/pilS recombination to increase dramatically when compared with WT values. Consequently, H-NS protein suppresses pilE intragenic transcription as well as antigenic variation through the pilE/pilS recombination system.,
language=,
type=