title: Identification of histidine kinases that act as sensors in the perception of salt stress in Synechocystis sp. PCC 6803.
abstract: In plants and microorganisms, salt stress regulates the expression of large numbers of genes. However, the machinery that senses salt stress remains to be characterized. In this study we identified sensory histidine kinases that are involved in the perception of salt stress in the cyanobacterium Synechocystis sp. strain PCC 6803. A library of strains with mutations in all 43 histidine kinases was screened by DNA microarray analysis of genomewide gene expression under salt stress. The results suggested that four histidine kinases, namely, Hik16, Hik33, Hik34, and Hik41, perceived and transduced salt signals. However, Hik33, Hik34, and Hik16 acting with Hik41 regulated the expression of different sets of genes. These histidine kinases regulated the expression of approximately 20% of the salt-inducible genes, whereas the induction of the remaining salt-inducible genes was unaffected by mutations in any of the histidine kinases, suggesting that additional sensory mechanisms might operate in the perception of salt stress. We also used DNA microarrays to investigate the effect of various salts on gene expression. Our results indicate that Hik33 responds to sodium salts and not to KCl, whereas the Hik16/Hik41 system responds only to NaCl.
authors.affiliation: Universität Rostock, FB Biowisenschaften, Pflanzenphysiologie, Albert Einsteinstrasse 3a, 18051 Rostock, Germany.
authors.forename: Kay
authors.initials: K
authors.lastname: Marin
authors.forename: Iwane
authors.initials: I
authors.lastname: Suzuki
authors.forename: Katsushi
authors.initials: K
authors.lastname: Yamaguchi
authors.forename: Kathrin
authors.initials: K
authors.lastname: Ribbeck
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yamamoto
authors.forename: Yu
authors.initials: Y
authors.lastname: Kanesaki
authors.forename: Martin
authors.initials: M
authors.lastname: Hagemann
authors.forename: Norio
authors.initials: N
authors.lastname: Murata
mesh_terms: D001483:Base Sequence; D000458:Cyanobacteria / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics* / Q000254:growth & development; D004269:DNA, Bacterial / Q000235:genetics; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D015723:Gene Library; D005798:Genes, Bacterial; D000071677:Histidine Kinase; D009154:Mutation; D020411:Oligonucleotide Array Sequence Analysis; D011494:Protein Kinases / Q000235:genetics* / Q000378:metabolism*; D012492:Salts / Q000494:pharmacology; D015398:Signal Transduction; D012965:Sodium Chloride / Q000494:pharmacology
chemical_list: D004269:DNA, Bacterial; D012492:Salts; D012965:Sodium Chloride; D011494:Protein Kinases; D000071677:Histidine Kinase