Published with permission of Horizon Scientific Press / Caister Academic Press.The primary steps in acclimation selleck chemical to environmental stress are the perception of such stress and transduction of the resulting signal. Organisms and/or individual cells are equipped with sensors and signal transducers that perceive and transduce signals from changing environment. They are mostly specific to individual types of environmental stress.The unicellular cyanobacteria have several features that make them particularly suitable for studies of stress responses at the molecular level. The general features of the plasma and thylakoid membranes of cyanobacterial cells are similar to those of the chloroplasts of higher plants in terms of lipid composition and the assembly of membranes.

Therefore, cyanobacteria can be expected to serve as powerful model systems for studying the molecular Inhibitors,Modulators,Libraries mechanisms of the responses and acclimation to stress [1,2], also these mechanisms may provide models that are applicable to higher plants as well.Many strains of cyanobacteria, e.g., Synechocystis sp. PCC 6803 (hereafter, Synechocystis), are naturally competent. It means that foreign DNA may be incorporated into the cells integrated into their genomes by homologous recombination at high frequency [3,4]. As a result, cyanobacteria are widely used by researchers for the production of mutants with disrupted genes of interest [5,6].Kaneko et al. determined the entire Inhibitors,Modulators,Libraries nucleotide sequence of the genome of Synechocystis [7] together with the entire sequences of four plasmids harbored by Synechocystis [8].

This is particularly useful as basic information, which can be exploited for genome-wide studies of gene expression. About 10 years ago, Takara Bio Co. (Ohtu, Japan) initiated the production of a genome-wide Inhibitors,Modulators,Libraries DNA microarrays Inhibitors,Modulators,Libraries for the analysis of gene expression in Synechocystis. The DNA microarray covers 3,079 (97%) of the 3,165 genes on the chromosome of Synechocystis, exluding 99 genes for transposases. It does not carry the genes from the Batimastat four plasmids as well. The original results of analysis of patterns of gene expression in this cyanobacterium can be found in the KEGG expression database (Lists of experimental data are available at http://www.genome.jp/kegg/expression/).In this review, we summarize recent progress in studies of sensors and signal transducers of environmental stress in Synechocystis that involved both systematic mutagenesis and the use of DNA microarrays.

2.?Discussion2.1. Potential Sensors and Signal Transducers in CyanobacteriaThe existence of two-component Gefitinib sensor-transducer systems has been well established in Escherichia coli [9] and Bacillus subtilis [10]. Each two-component system consists of a histidine kinase (Hik) and a cognate response regulator (Rre). In E. coli and B. subtilis, the genes for the two components of a single system are, in many cases, located close to one another on the chromosome.