Cyclic Nucleotides, the Photosynthetic Apparatus and Response to a UV-B Stress in the Cyanobacterium Synechocystis sp. PCC 6803
| Autor: | Otilia Cheregi, Imre Vass, Jean Houmard, Jean-Charles Cadoret, Bernard Rousseau, Cosmin Sicora, Irène Perewoska |
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| Rok vydání: | 2005 |
| Předmět: |
Cell signaling
DNA Repair Photosystem II Ultraviolet Rays Cellular homeostasis Biochemistry Open Reading Frames Cyclic nucleotide chemistry.chemical_compound Cyclic AMP Homeostasis Nucleotide Photosynthesis Cyclic GMP Molecular Biology chemistry.chemical_classification biology Phosphoric Diester Hydrolases Reverse Transcriptase Polymerase Chain Reaction Synechocystis Photosystem II Protein Complex Phosphodiesterase Cell Biology biology.organism_classification Adaptation Physiological chemistry Signal transduction DNA Damage Signal Transduction |
| Zdroj: | Journal of Biological Chemistry. 280:33935-33944 |
| ISSN: | 0021-9258 |
| DOI: | 10.1074/jbc.m503153200 |
| Popis: | Cyclic nucleotides cAMP and cGMP are ubiquitous signaling molecules that mediate many adaptative responses in eukaryotic cells. Cyanobacteria present the peculiarity among the prokaryotes of having the two types of cyclic nucleotide. Cellular homeostasis requires both cyclases (adenylyl/guanylyl, for their synthesis) and phosphodiesterases (for their degradation). Fully segregated null mutants have been obtained for the two genes, sll1624 and slr2100, which encode putative cNMP phosphodiesterases. We present physiological evidence that the Synechocystis PCC 6803 open reading frame slr2100 could be a cGMP phosphodiesterase. In addition, we show that Slr2100, but not Sll1624, is required for the adaptation of the cells to a UV-B stress. UV-B radiation has deleterious effects for photosynthetic organisms, in particular on the photosystem II, through damaging the protein structure of the reaction center. Using biophysical and biochemical approaches, it was found that Slr2100 is involved in the signal transduction events which permit the repair of the UV-B-damaged photosystem II. This was confirmed by quantitative reverse transcriptase-PCR analyses. Altogether, the data point to an important role for cGMP in signal transduction and photoacclimation processes during a UV-B stress. |
| Databáze: | OpenAIRE |
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