Dataset Information

The orthologue of the RNA chaperone Hfq is essential for cell motility of the cyanobacterium Synechocystis PCC 6803

ABSTRACT: The gene ssr3341 was previously suggested to encode an orthologue of the RNA chaperone Hfq in Synechocystis sp. strain PCC 6803. When a phototactic strain of this cyanobacterium was insertionally inactivated at ssr3341, the mutants were not transformable, and were rendered non-phototactic compared to the wild type. The loss of motility was complemented by re-introduction of the wild-type gene, correlated with the re-establishment of type IV pili on the cell surface. Microarray analyses revealed a small set of genes with drastically reduced transcript levels in the knock-out mutant over wild-type cells. Among the most strongly affected genes are with slr1667, slr1668, slr2015, slr2016 and slr2018 five genes which belong to two operons that previously were shown to be involved in motility and controlled by the SYCRP1-cAMP receptor protein. This fact constitutes a link between cAMP signalling, motility, and the involvement of RNA-based regulation. This is the first report demonstrating a functional role of Hfq in cyanobacteria. Keywords: comparative expression profiling Overall design: Microarray experiments were carried out as two-color hybridizations on custom designed 8-pack 15K Synechocystis sp. microarrays (AMADID 016989) from Agilent Technologies (Santa Clara, USA).

INSTRUMENT(S): Agilent-016989 Synechocystis sp. PCC 6803 8x15K custom array

SUBMITTER: Hans-Joachim Mollenkopf

PROVIDER: GSE10708 | GEO | 2008-03-15

SECONDARY ACCESSION(S): PRJNA107587

REPOSITORIES: GEO

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The cyanobacterial homologue of the RNA chaperone Hfq is essential for motility of Synechocystis sp. PCC 6803.

Dienst Dennis D Dühring Ulf U Mollenkopf Hans-Joachim HJ Vogel Jörg J Golecki Jochen J Hess Wolfgang R WR Wilde Annegret A

Microbiology (Reading, England) 20081001 Pt 10

The ssr3341 locus was previously suggested to encode an orthologue of the RNA chaperone Hfq in the cyanobacterium Synechocystis sp. strain PCC 6803. Insertional inactivation of this gene resulted in a mutant that was not naturally transformable and exhibited a non-phototactic phenotype compared with the wild-type. The loss of motility was complemented by reintroduction of the wild-type gene, correlated with the re-establishment of type IV pili on the cell surface. Microarray analyses revealed a ...[more]

PMID: 18832319

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