title: Evidence for a major role of antisense RNAs in cyanobacterial gene regulation.
abstract: Information on the numbers and functions of naturally occurring antisense RNAs (asRNAs) in eubacteria has thus far remained incomplete. Here, we screened the model cyanobacterium Synechocystis sp. PCC 6803 for asRNAs using four different methods. In the final data set, the number of known noncoding RNAs rose from 6 earlier identified to 60 and of asRNAs from 1 to 73 (28 were verified using at least three methods). Among these, there are many asRNAs to housekeeping, regulatory or metabolic genes, as well as to genes encoding electron transport proteins. Transferring cultures to high light, carbon-limited conditions or darkness influenced the expression levels of several asRNAs, suggesting their functional relevance. Examples include the asRNA to rpl1, which accumulates in a light-dependent manner and may be required for processing the L11 r-operon and the SyR7 noncoding RNA, which is antisense to the murF 5' UTR, possibly modulating murein biosynthesis. Extrapolated to the whole genome, approximately 10% of all genes in Synechocystis are influenced by asRNAs. Thus, chromosomally encoded asRNAs may have an important function in eubacterial regulatory networks.
authors.affiliation: Faculty of Biology and Freiburg Initiative in Systems Biology, University of Freiburg, Freiburg 79104, Germany.
authors.forename: Jens
authors.initials: J
authors.lastname: Georg
authors.forename: Björn
authors.initials: B
authors.lastname: Voss
authors.forename: Ingeborg
authors.initials: I
authors.lastname: Scholz
authors.forename: Jan
authors.initials: J
authors.lastname: Mitschke
authors.forename: Annegret
authors.initials: A
authors.lastname: Wilde
authors.forename: Wolfgang R
authors.initials: WR
authors.lastname: Hess
mesh_terms: D015964:Gene Expression Regulation, Bacterial; D020411:Oligonucleotide Array Sequence Analysis; D016372:RNA, Antisense / Q000235:genetics*; D012329:RNA, Bacterial / Q000235:genetics*; D022661:RNA, Untranslated / Q000235:genetics; D015203:Reproducibility of Results; D015398:Signal Transduction / Q000235:genetics; D046939:Synechocystis / Q000235:genetics*; D049490:Systems Biology / Q000379:methods
chemical_list: D016372:RNA, Antisense; D012329:RNA, Bacterial; D022661:RNA, Untranslated