Comparative gene expression analysis in field vs. laboratory grown sporophytes of Saccharina latissima (Phaeophyceae)
ABSTRACT: To explore possible interactive effects of UV-radiation, temperature and growth conditions, cultivated and field sporophytes of Saccharina latissima were exposed for 24h to UV-radiation at three different temperatures (2,7 & 12°C). Gene expression profiles under UV-radiation at different temperatures were assessed through microarray hybridizations, afterwards comparisons of gene expression profiles in field and culture sporophytes were carried out.
Project description:Sporophytes of Saccharina latissima were exposed for two weeks to 12 different combinations of photosynthetically active radiation and UVR at three different temperatures (2,7,12 C). Maximum quantum yield of photosystem II was determined twice a week during the experimental duration for observing the extent of photoinhibition. For investigating molecular mechanisms of acclimation to high photosynthetically radiation, and UVR gene expression profiles were assessed through microarray hybridizations.
Project description:Effect of PAR and temperature stress on the gene expression Saccharina latissima. Total RNA of stress treatments (low PAR 2° and 17°C, high PAR 2° and 17°C) was hybridized against the control treatment (low PAR 12°C); hybridizations were carried out in 4 replicates.
Project description:In the present study we have used a new custom made Affymetrix GrapeGen GeneChip to investigate gene expression responses of grapevine cultivar Malbec to one dose of biologically effective UV-B radiation (4.75 kJ m-2 d-1), administered at two different intensities (16 h, to 8.25 µW cm-2 or 4 h, to 33 µW cm2 UV-B).
Project description:Ultra-violet (UV) and high-intensity visible (VIS) radiation are environmental stressors known to harm photosynthetic organisms through the generation of reactive intermediates that damage photosynthetic machinery. This study shows the potential of using a thermoacidophilic red alga of the order Cyanidiales to model in situ algal gene expression dynamics as a function of UV exposure and seasonal shifts in UV-VIS intensity. These algae exhibit a dynamic seasonal biomass fluctuation referred to as 'mat decline' where viability drastically decreases as seasonal UV-VIS irradiance intensity increases. In Yellowstone National Park (YNP), temporal experiments coupling UV irradiance manipulations (filtering) with whole-community transcription profiling revealed significant cyanidial gene expression changes occurring as a result of exposure to UV, and that patterns of response adjust across low and high irradiance time periods. Separate analyses examined genes responding to either increasing seasonal UV or VIS intensity, or by the combined effects of both irradiance wavelengths (UV and VIS). Results not only corroborated known physiological changes to solar irradiance, but also suggested the strategies employed to deal with excess VIS and UV intensity may be highly integrated. Finally, a suite of comparative analyses determined the relative utility of environmental transcriptomics technologies in studying ecologically-relevant expression patterns. Results suggest in situ expression profiles will improve understanding of how photosynthetic organisms are responding to environmental stressors as they are observed in nature. 16 samples with 3 biological replicates each.
Project description:We experimentally generated a genome-wide gene expression data. To this end, we first collected samples of three important haploid developmental stages, specifically germinating spores (gametophyte_1), protonemata (gametophyte_2) and young gametophores (gametophyte_3) (four biological replicates each). We also collected three developmental stages of the diploid phase (sporophyte), specifically sporophytes shorter than 5mm (sporophyte_1), elongated needle-like sporophytes (sporophyte_2), and sporophytes with swollen capsules (sporophyte_3)
Project description:Detect the global transcriptional changes occuring during spreading and maintenance of systemic post transcriptional silencing . Test the hypothesis that activation of systemic PTGS induces parallel antiviral defense pathways. Gene expression was analysed by MACE method (Massive Analysis of cDNA Ends) on total RNA extracted from leaf tissues of WT plants (WT), and GFP6.4 presenting no-silencing (NS sample), ongoing spreading of silencing (OS) and maintenance of silencing (SS). Plants were grown in parallel, and silencing state was monitored under UV. After 3 weeks of growth, total RNAs were extracted using the Trizol method from leaf tissues of 2-3 leaf stage plants. A total of 4 plants were sampled per variable (WT/NS/OS/SS). RNA from 4 plants were pooled and sequenced.