Synechocystis sp. PCC 6803
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA298210 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Glutamine synthetase (GS), a key enzyme in biological nitrogen assimilation, is regulated in multiple ways in response to varying nitrogen sources and levels. Here we show a small regulatory RNA, NsiR4 (nitrogen stress induced RNA 4), which plays an important role in the regulation of GS in cyanobacteria. NsiR4 expression in the unicellular Synechocystis sp. PCC 6803 and in the filamentous, nitrogen-fixing Anabaena sp. PCC 7120 is stimulated through nitrogen-limitation via NtcA, the global transcriptional regulator of genes involved in nitrogen metabolism. NsiR4 is widely conserved throughout the cyanobacterial phylum, suggesting a conserved function. In silico target prediction, transcriptome profiling upon pulse overexpression and site-directed mutagenesis experiments using a heterologous reporter system showed that NsiR4 interacts with the 5’UTR of gifA mRNA, which encodes glutamine synthetase inactivating factor IF7. In Synechocystis, we observed an inverse relationship between the levels of NsiR4 and the accumulation of IF7 in vivo. This NsiR4-dependent modulation of gifA (IF7) mRNA accumulation influenced the glutamine pool and thus NH4+ assimilation via glutamine synthetase. As a second target, we identified ssr1528, a hitherto uncharacterized nitrogen-regulated gene. Competition experiments between wild type and an NsiR4 knock-out mutant showed that the lack of NsiR4 led to decreased acclimation capabilities of Synechocystis towards oscillating nitrogen levels. These results suggest a role for NsiR4 in the regulation of nitrogen metabolism in cyanobacteria, especially for the adaptation to rapid changes in available nitrogen sources and concentrations. NsiR4 is the first identified bacterial sRNA regulating the primary assimilation of a macronutrient.
2015-10-20 | GSE73840 | GEO
Project description:Acclimation of oxygenic photosynthesis to iron starvation is controlled by the sRNA IsaR1 in cyanobacteria
| PRJNA345038 | ENA
Project description:Comparison between GT and rre37 overexpressed strains of cyanobacteria
| PRJNA203541 | ENA
Project description:Comparison between GT and hoxH mutant strains of cyanobacteria
| PRJNA308195 | ENA
Project description:Synechocystis sp. PCC 6803 sRNA raw sequence reads
| PRJNA309143 | ENA
Project description:Comparison between GT and ntcA-overexpressing strains of cyanobacteria [nitrogen-replete conditions]
| PRJNA236619 | ENA
Project description:Comparison between GT and ntcA-overexpressing strains of cyanobacteria [nitrogen-depleted conditions]
| PRJNA236620 | ENA
Project description:Unicellular cyanobacteria that do not fix nitrogen can survive prolonged periods of nitrogen starvation as bleached cells in a non-growing, dormant state. Upon re-addition of a usable nitrogen source, bleached cultures re-green within 48 hours and the cells return to vegetative growth. Here we investigated the process of resuscitation at the physiological and molecular level. Almost immediately upon nitrate addition, the cells initiate an amazingly organized resuscitation program: they first turn on respiration, gaining energy and activating the genes of the entire translational apparatus, genes for ATP synthesis and nitrate assimilation. Only after about 12 hours, the cells rebuild the photosynthetic apparatus and switch on photosynthesis. Analysis of the transcriptome in recovering cells shows a perfect match to the physiological processes and reveals a paramount dynamics of non-coding RNAs in awaking cells. This genetically encoded program ensures rapid colonization of habitats, in which nitrogen starvation imposes a recurring growth limitation.
2016-06-15 | GSE83363 | GEO
Project description:Unicellular cyanobacteria that do not fix nitrogen can survive prolonged periods of nitrogen starvation as bleached cells in a non-growing, dormant state. Upon re-addition of a usable nitrogen source, bleached cultures re-green within 48 hours and the cells return to vegetative growth. Here we investigated the process of resuscitation at the physiological and molecular level. Almost immediately upon nitrate addition, the cells initiate an amazingly organized resuscitation program: they first turn on respiration, gaining energy and activating the genes of the entire translational apparatus, genes for ATP synthesis and nitrate assimilation. Only after about 12 hours, the cells rebuild the photosynthetic apparatus and switch on photosynthesis. Analysis of the transcriptome in recovering cells shows a perfect match to the physiological processes and reveals a paramount dynamics of non-coding RNAs in awaking cells. This genetically encoded program ensures rapid colonization of habitats, in which nitrogen starvation imposes a recurring growth limitation. Synechocstis PCC 6803 WT cells were subjected to nitrogen limitation for 14d, then nitrogen was re-added to monitor recovery of the cells. Samples were taken before nitrogen depletion, after 14d of nitrogen depletion and 4h, 13h, 24h and 48h after nitrogen re-addition. Samples were taken in biological replicates for all timepoints besides 48h nitrogen recovery.
2016-06-15 | E-GEOD-83363 | biostudies-arrayexpress
Project description:The omega subunit of the RNA polymerase core directs transcription efficiency in cyanobacteria
| PRJNA224191 | ENA