Project description:To identify the concurrent effects of multiple environmental factors on gene expression under natural climatic fluctuations in rice, we examined global gene expression patterns in two fields typical of the main modes of rice cultivation, over two seasons, each comprising 15 time-points in three different genotypes Two time-series of 15 time-points, one for each season (dry and wet) over two different fields
Project description:Freshwater ecosystems can be largely affected by neighboring agriculture fields where potential fertilizer nitrate run-off may leach into surrounding water bodies. To counteract this eutrophic driver, farmers often utilize denitrifying woodchip bioreactors (WBRs) in which a consortium of microorganisms convert the nitrate into nitrogen-gases in anoxia, fueled by the degradation of lignocellulose. Polysaccharide-degrading strategies have been well-described for various aerobic and anaerobic systems, including the use of carbohydrate-active enzymes, utilization of lytic polysaccharide monooxygenases (LPMOs) and other redox enzymes, as well as the use of cellulosomes and polysaccharide utilization loci. However, for denitrifying microorganisms, the lignocellulose-degrading strategies remain largely unknown. Here, we have applied a combination of enrichment techniques, gas measurements, multi-omics approaches, and amplicon sequencing of fungal ITS and procaryotic 16S rRNA genes to highlight microbial drivers for lignocellulose transformation in woodchip bioreactors with the aim to provide an in-depth characterization of the indigenous microorganisms and their active enzymes. Our findings highlight a microbial community enriched for lignocellulose-degrading denitrifiers with key players from Giesbergeria, Cellulomonas, Azonexus, and UBA5070, including polysaccharide utilization loci from Bacteroidetes. A wide substrate specificity is observed among the many expressed carbohydrate active enzymes (CAZymes), evidencing a swift degradation of lignocellulose, including even enzymes with auxiliary activities whose functionality is still puzzling under strict anaerobic conditions.
Project description:To identify the concurrent effects of multiple environmental factors on gene expression under natural climatic fluctuations in rice, we examined global gene expression patterns in two fields typical of the main modes of rice cultivation, over two seasons, each comprising 15 time-points in three different genotypes
Project description:Transcript abundance profiles were examined over the first 24 hours of germination in rice grown under anaerobic conditions. Transcript abundance profiles were also examined for rice grown under aerobic conditions for 24 h and then switched to anaerobic conditions and vice versa.
Project description:Degradation of polycyclic aromatic hydrocarbons (PAHs) such as naphthalene by anaerobic microorganisms is poorly understood. Strain NaphS2, an anaerobic sulfate reducing marine delta-proteobacterium is capable of using naphthalene and the aromatic compound benzoate, as well as pyruvate, as an electron donors in the presence of sulfate. In order to identify genes involved in the naphthalene degradation pathway, we compared gene expression in NaphS2 during growth on benzoate vs. pyruvate, naphthalene vs. pyruvate, and naphthalene vs benzoate.
Project description:Rice (Oryza sativa L.) seeds can germinate in complete absence of oxygen. Under anoxia, the rice coleoptile elongates, reaching a length greater than that of the aerobic one. In this series, we compare the transcriptome of rice coleoptiles grown under aerobic and anaerobic conditions. Lasanthi-Kudahettige, R, et. al. Plant Physiology (2007). Transcript Profiling of the Anoxic Rice Coleoptile. Keywords: stress response
Project description:Rice grown in paddy fields prefers to use ammonium ions as a major source of inorganic nitrogen. Glutamine synthetase (GS) catalyzes the conversion of ammonium ions to glutamine. In three cytosolic GS in rice, OsGS1;1 has the critical role for normal growth and grain filling. To understand a role of GS1;1, we performed transcriptional profiling of wild type Nipponbare and GS1;1 mutant plants in seedling using the Agilent Rice Oligo Microarray.
Project description:During germination, the availability of sugars, oxygen, or cellular energy fluctuates under dynamic environmental conditions, and the global RNA profile of rice genes can be affected by their availabilities. In the aerobically germinating rice embryos, most sugar-regulated genes are responsive to low energy and anaerobic conditions, indicating that sugar-regulation is closely associated with energy and anaerobic signaling. The interference pattern of sugar-regulation by either anaerobic or low energy conditions indicates that induction is likely the more prevalent regulatory mechanism than repression for the alteration in the expression of sugar-regulated genes in aerobically germinating rice embryos. Among the aerobically sugar-regulated genes, limited genes exhibit sugar regulation under anaerobic conditions, indicating that anaerobic conditions strongly influence sugar-regulated gene expression. Anaerobically responsive genes are highly overlapped with low-energy responsive genes. In particular, the expression levels of anaerobically downregulated genes are consistent with those induced by low energy-conditions, suggesting that anaerobic downregulation results from the prevention of aerobic respiration due to the absence of the final electron acceptor, i.e., molecular oxygen. It was noted that abscisic acid (ABA)-responsive genes were over-representative of the genes upregulated under low energy conditions, in contrast to the downregulated genes. This suggests that either ABA itself or upstream signaling components of the ABA signaling pathway are likely to be involved in the signaling pathways activated by low energy conditions.