Project description:Gene expression of different flocculent (HS 10 and HS 34) and powdery (HS 12 and HS 37) yeast strains compared to each other during exponential and stationary growth phase was analysed. The isolation of RNA was done by disruption of the cells under liquid nitrogen using mortar and pistil and then the Qiagen RNeasy Midi Kit with some modifications within the manufacturers´ protocol and the Qiagen RNase-Free DNase Set were applied. 6 µg of the total RNA per sample was used for each microarray experiments. The indirect labelling by the tyramide-signal-amplification method (MicromaxTM TSATM labelling and detection Kit from Perkin Elmer life sciences) was used to increase the Cy3 and Cy5 signals of microarray detection. Each cDNA containing Biotin- and Fluorescein-nucleotides respectively was purified with a QIAquick PCR purification kit and suspended in 11 µl of the formamide containing hybridization buffer. The slides were hybridized at 42°C over night under a cover slip. The microarrays were scanned by the Axon 4000B scanner; image intensity data were extracted and analysed with GenePix® Pro 6.0 software. Data from different scans of Dye-swap experiment were extracted by GenePix Pro 6.0 software, normalized and united. An outliertest has been applied in order to find outliers amongst the gene replicats. Subsequently, a t-test (1% and 5% probability of error) has been used in order to find regulated genes. Keywords: sorted yeast cells
Project description:Gene expression of different flocculent (HS 10 and HS 34) and powdery (HS 12 and HS 37) yeast strains compared to each other during exponential and stationary growth phase was analysed. The isolation of RNA was done by disruption of the cells under liquid nitrogen using mortar and pistil and then the Qiagen RNeasy Midi Kit with some modifications within the manufacturers´ protocol and the Qiagen RNase-Free DNase Set were applied. 6 µg of the total RNA per sample was used for each microarray experiments. The indirect labelling by the tyramide-signal-amplification method (MicromaxTM TSATM labelling and detection Kit from Perkin Elmer life sciences) was used to increase the Cy3 and Cy5 signals of microarray detection. Each cDNA containing Biotin- and Fluorescein-nucleotides respectively was purified with a QIAquick PCR purification kit and suspended in 11 µl of the formamide containing hybridization buffer. The slides were hybridized at 42°C over night under a cover slip. The microarrays were scanned by the Axon 4000B scanner; image intensity data were extracted and analysed with GenePix® Pro 6.0 software. Data from different scans of Dye-swap experiment were extracted by GenePix Pro 6.0 software, normalized and united. An outliertest has been applied in order to find outliers amongst the gene replicats. Subsequently, a t-test (1% and 5% probability of error) has been used in order to find regulated genes. Keywords: sorted yeast cells Microarray experiments were realised with dye swap.
Project description:In this study, we characterized the fatty acid production in Neochloris aquatica at transcriptomics and biochemical levels under limiting, normal, and excess nitrate concentrations in different growth phases. At the stationary phase, N. aquatica mainly produced saturated fatty acids such as stearic acid under the limiting nitrate concentration, which is suitable for biodiesel production. However, it produced polyunsaturated fatty acids such as α-linolenic acid under the excess nitrate concentration, which has nutritional values as food supplements. In addition, RNA-seq was employed to identify genes and pathways that were being affected in N. aquatica for three growth phases in the presence of the different nitrate amounts. Genes that are responsible for the production of saturated fatty acids were upregulated in the cells grown under a limiting nitrogen amount while genes that are responsible for the production of polyunsaturated fatty acid were upregulated in the cells grown under excess nitrogen amount. Further analysis showed more genes differentially expressed (DEGs) at the loga- rithmic phase in all conditions while a relatively steady trend was observed during the transition from the logarithmic phase to the stationary phase under limiting and excess nitrogen. Our results provide a foundation for identifying developmentally important genes and understanding the biological processes in the different growth phases of the N. aquatica in terms of biomass and lipid production.