Project description:A functional gene microarray was developed and used to investigate phytoplankton community composition and gene expression in the English Channel. Genes encoding the CO2 fixation enzyme RuBisCO (rbcL) and the nitrate assimilation enzyme nitrate reductase (NR) representing several major groups of phytoplankton were included as oligonucleotide probes on the 'phytoarray'. Five major groups of eukaryotic phytoplankton that possess the Type 1D rbcL gene were detected, both in terms of presence (DNA) and activity (rbcL gene expression). Changes in relative signal intensity among the Type 1D rbcL probes indicated a shift from diatom dominance in the spring bloom to dominance by haptophytes and flagellates later in the summer. Because of the limitations of a smaller database, NR probes detected fewer groups, but due to the greater diversity among known NR sequences, NR probes provided higher phylogenetic resolution than did rbcL probes, and identified two uncultivated diatom phylotypes as the most abundant (DNA) and active (NR gene expression) in field samples. Unidentified chlorophytes and the diatom Phaeodactylum tricornutum were detected at both the DNA and cDNA (gene expression) levels. The reproducibility of the array was evaluated in several ways and future directions for further improvement of probe development and sensitivity are outlined. The phytoarray provides a relatively high resolution, high throughput approach to assessing phytoplankton community composition in marine environments. Keywords: seawater natural assemblages, functional gene expression
Project description:A functional gene microarray was developed and used to investigate phytoplankton community composition and gene expression in the English Channel. Genes encoding the CO2 fixation enzyme RuBisCO (rbcL) and the nitrate assimilation enzyme nitrate reductase (NR) representing several major groups of phytoplankton were included as oligonucleotide probes on the 'phytoarray'. Five major groups of eukaryotic phytoplankton that possess the Type 1D rbcL gene were detected, both in terms of presence (DNA) and activity (rbcL gene expression). Changes in relative signal intensity among the Type 1D rbcL probes indicated a shift from diatom dominance in the spring bloom to dominance by haptophytes and flagellates later in the summer. Because of the limitations of a smaller database, NR probes detected fewer groups, but due to the greater diversity among known NR sequences, NR probes provided higher phylogenetic resolution than did rbcL probes, and identified two uncultivated diatom phylotypes as the most abundant (DNA) and active (NR gene expression) in field samples. Unidentified chlorophytes and the diatom Phaeodactylum tricornutum were detected at both the DNA and cDNA (gene expression) levels. The reproducibility of the array was evaluated in several ways and future directions for further improvement of probe development and sensitivity are outlined. The phytoarray provides a relatively high resolution, high throughput approach to assessing phytoplankton community composition in marine environments. Keywords: seawater natural assemblages, functional gene expression Two functional genes, nitrate reductase and RuBisCO, 4 - 8 replicate features per array
Project description:Campeiostachys nutans, a dominant perennial grass in the Qinghai-Tibet Plateau, exhibits high tolerance to salt stress. The Salt Overly Sensitive (SOS) pathway is key to plant salt stress tolerance. However, the pivotal role of the SOS pathway in response to salt stress in C. nutans remains unknown. Here, we identified CnbHLH130 as a novel transcriptional activator of CnCBL10, directly binds to the G-box motif in the promoter. CnbHLH130 responds to salt stress and positively regulate salt tolerance in rice and C. nutans. Interestingly, we found CnCBL10 and CnCIPK4 interact with CnbHLH130 by a Y2H screening assay. The interactions were confirmed by split-luciferase complementation (split-LUC), Pull-down, Co-immunoprecipitation (Co-IP) and bimolecular fluorescence complementation (BiFC) assays. Moreover, CnbHLH130 enhanced the interaction between CnCBL10 and CnCIPK4, which further phosphorylate and activate Na+/H+ antiporter CnSOS1 to exclude excess cytosolic Na+ from cells in the shoots. Genetic evidence showed that CnCBL10, CnCIPK4 and CnbHLH130 coordinately regulates salt tolerance in plants. In summary, this study demonstrated that CnbHLH130 acts as a novel core component and transcriptional activator regulating CnCBL10-CnCIPK4 mediated SOS pathway, thus conferring to the salt tolerance in C. nutans. This work advanced our understandings of how an alpine plant greatly survived in the Qinghai-Tibet Plateau by concise regulation of the SOS pathway in response to salt stress.
Project description:To investigate the effects of C. nutans DCM fraction on HeLa cells using transcriptomic analysis. We then performed gene expression profiling analysis using data obtained from RNA-seq of two different condition at two replicates.