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Nucleoprotein filament formation is the structural basis for bacterial protein H-NS gene silencing.

ABSTRACT: H-NS is an abundant nucleoid-associated protein in bacteria that globally silences genes, including horizontally-acquired genes related to pathogenesis. Although it has been shown that H-NS has multiple modes of DNA-binding, which mode is employed in gene silencing is still unclear. Here, we report that in H-NS mutants that are unable to silence genes, are unable to form a rigid H-NS nucleoprotein filament. These results indicate that the H-NS nucleoprotein filament is crucial for its gene silencing function, and serves as the fundamental structural basis for gene silencing by H-NS and likely other H-NS-like bacterial proteins.

SUBMITTER: Lim CJ

PROVIDER: S-EPMC3396134 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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Nucleoprotein filament formation is the structural basis for bacterial protein H-NS gene silencing.

Lim Ci Ji CJ Lee Sin Yi SY Kenney Linda J LJ Yan Jie J

Scientific reports 20120713

H-NS is an abundant nucleoid-associated protein in bacteria that globally silences genes, including horizontally-acquired genes related to pathogenesis. Although it has been shown that H-NS has multiple modes of DNA-binding, which mode is employed in gene silencing is still unclear. Here, we report that in H-NS mutants that are unable to silence genes, are unable to form a rigid H-NS nucleoprotein filament. These results indicate that the H-NS nucleoprotein filament is crucial for its gene silen ...[more]

PMID: 22798986

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