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ChIP-chip of HA-tagged Lsr2 in Mycobacterium tuberculosis and Mycobacterium smegmatis

ABSTRACT: Bacterial nucleoid-associated proteins play important roles in chromosome organization and global gene regulation. We find that Lsr2 of Mycobacterium tuberculosis is a novel nucleoid-associated protein that specifically binds AT-rich regions of the genome, including regions encoding major virulence factors, such as the ESX secretion systems, the lipid virulence factors PDIM/PGL, and the PE/PPE families of antigenic proteins. Comparison of genome-wide binding data with expression data indicates that Lsr2 binding results in transcriptional repression. Domain swamping experiments demonstrate that Lsr2 has an N-terminal dimerization domain and a C-terminal DNA binding domain. NMR analysis of the DNA binding domain of Lsr2 and its interaction with DNA reveals a novel structure and a unique mechanism that enables Lsr2 to discriminately target AT-rich sequences through interactions with the minor groove of DNA. Taken together, we provide evidence that mycobacteria have employed a structurally distinct molecule with an apparently different DNA recognition mechanism to achieve an equivalent function as the Enterobacteriaceae H-NS, coordinating global gene regulation and virulence in this group of medically important bacteria.

ORGANISM(S): Mycolicibacterium smegmatis MC2 155 Mycolicibacterium smegmatis Mycobacterium tuberculosis H37Rv

PROVIDER: GSE18652 | GEO | 2009/11/15

SECONDARY ACCESSION(S): PRJNA121589

REPOSITORIES: GEO

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ChIP-chip of HA-tagged Lsr2 in Mycobacterium tuberculosis and Mycobacterium smegmatis

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