Project description:October 2010 surface seawater collected from Pacifica pier was incubated with 14 different substrates for 12 hours. Community RNA was extracted and hybridized to a Roche Nimblegen microarray and analyzed by NanoSIMS to obtain isotope ratio data for all probe spots.
Project description:October 2013 surface seawater collected from Monterey Bay was incubated with 1 micromolar 13C labeled glucose, starch, acetate, lipids, protein, or amino acids for 12 hours. Community RNA was extracted and hybridized to a Roche Nimblegen microarray and analyzed by NanoSIMS to obtain isotope ratio data for all probe spots.
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:October 2013 surface seawater collected from Monterey Bay was incubated with 1 micromolar 13C labeled glucose, starch, acetate, lipids, protein, or amino acids for 12 hours. Community RNA was extracted and hybridized to a Roche Nimblegen microarray and analyzed by NanoSIMS to obtain isotope ratio data for all probe spots. Two Chips for fluorescence, and 15 Chips for different substrates from samples incubated for 12 or 36 hours.
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