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Evidence for a major role of antisense RNAs in cyanobacterial gene regulation

ABSTRACT: The model cyanobacterium Synechocystis sp. PCC 6803 was used for a systematic survey on the number and types of antisense (as)RNAs. A tiled microarray was constructed with probes for both strands of the genes or intergenic spacers with candidate transcripts predicted by an algorithm and an equally sized and distributed control set. The resulting 102,739 individual probes cover an accumulated length of 1,441,146 nt or about 40% of the total chromosome sequence of Synechocystis 6803. Hybridization of this array with total RNA isolated from cultures raised under different growth conditions identified a high number of transcripts from intergenic spacers and in antisense orientation to known genes (natural cis-asRNAs). Extrapolated to the whole genome, around 10% of all open reading frames in Synechocystis 6803 may have a corresponding asRNA, suggesting a much more important role of chromosomally encoded asRNAs in bacteria then anticipated so far. Keywords: stress response 4 RNA hybridizations, 2 DNA controls. The raw data from the DNA hybridizations are in the GSE14410_DNA_1.txt and GSE14410_DNA_2.txt files.

ORGANISM(S): Synechocystis sp. PCC 6803

SUBMITTER: Jan Mitschke

PROVIDER: E-GEOD-14410 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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