Project description:Whole genome arrays have been used to analyze the transcriptomic response to vanadium stress in rice root. Identify genes and pathways that would respond to vanadium stress
Project description:This experiment was to determine genome wide qualitative and quantitative differences in transcription starts under conditions of availability of iron or vanadium or molybdenum which act as co-factors for different nitrogenase isoenzymes. In response to availability of the co-factors transcription initiation is mediated by three paralogs of vanadium nitrogenase activator VnfA1, VnfA2 and, VnfA3. ChIP-Seq data for VnfA1 and VnfA3 will be submitted separately.
Project description:The enhancer binding protein VnfA1 of Azotobacter vinelandii has two paralogs as well VnfA2 and VnfA3. This experiment was carried out to compare the binding sites of VnfA1 and VnfA3 under conditions of vanadium availability and its absence. This is important for the regulation of expression of alternative nitrogenase isoenzymes in response to metal availability.
Project description:Single cell RNA sequencing of 3D liver spheroid exposed to vanadium pentoxide (V2O5), titanium dioxide (TiO2), or graphene oxide (GO) was used to elucidate the toxicological mechanisms of different nanoparticles.
Project description:Plants aquire nitrogen from the soil, most commonly in the form of either nitrate or ammonium. Unlike ammonium, nitrate must be reduced (with NADH and ferredoxin as electron donors) prior to assimilation. Thus, nitrate nutrition imposes a substantially greater energetic cost than ammonium nutrition. Our goal was to compare the transcriptomes of nitrate-supplied and ammonium-supplied plants, with a particular interest in characterizing the differences in redox metabolism elicited by different forms of inorganic nitrogen. We used microarrays to compare the short-term transcriptional response to either nitrogen supply or ammonium supply in Arabidopsis roots. Genes upregulated or downregulated by nitrate only, ammonium only, or both ammonium and nitrate were identified and analyzed.
Project description:Ammonia is a ubiquitous, toxic by-product of cell metabolism. Its high membrane permeability and proton affinity causes ammonia to accumulate inside acidic lysosomes in its poorly membrane-permeant form: ammonium (NH4+). Ammonium buildup compromises lysosomal function, suggesting the existence of mechanisms that protect cells from ammonium toxicity. Here, we identified SLC12A9 as a lysosomal regulator of ammonium export that preserves lysosomal homeostasis. SLC12A9 knockout cells showed grossly enlarged lysosomes and elevated ammonium content. These phenotypes were reversed upon removal of the metabolic source of ammonium or dissipation of the lysosomal pH gradient. Lysosomal chloride increased in SLC12A9 knockout cells and chloride binding by SLC12A9 was required for ammonium transport. Our data indicate that SLC12A9 function is central for the handling of lysosomal ammonium and chloride, an unappreciated, fundamental mechanism of lysosomal physiology that may have special relevance in tissues with elevated ammonia, such as tumors.
2024-09-12 | GSE276655 | GEO
Project description:Panzhihua vanadium seasons distribution
Project description:Anaerobic ammonium-oxidising (anammox) bacteria, members of the ‘Candidatus Brocadiaceae’ family, play an important role in the nitrogen cycle and are estimated to be responsible for about half of the oceanic nitrogen loss to the atmosphere. Anammox bacteria combine ammonium with nitrite and produce dinitrogen gas via the intermediates nitric oxide and hydrazine (anammox reaction) while nitrate is formed as a by-product. These reactions take place in a specialized, membrane-bound compartment called the anammoxosome. Therefore, the substrates ammonium, nitrite and product nitrate have to cross the outer-, cytoplasmic- and anammoxosome membranes to enter or exit the anammoxosome. The genomes of all anammox species harbour multiple copies of ammonium-, nitrite- and nitrate transporter genes. Here we investigated how the distinct genes for ammonium-, nitrite- and nitrate- transport were expressed during substrate limitation in membrane bioreactors. Transcriptome analysis of Kuenenia stuttgartiensis planktonic cells under ammonium-limitation showed that three of the seven ammonium transporter genes and one of the six nitrite transporter genes were significantly upregulated, while another ammonium and nitrite transporter gene were downregulated in nitrite limited growth conditions. The two nitrate transporters were expressed to similar levels in both conditions. In addition, genes encoding enzymes involved in the anammox reaction were differentially expressed, with those using nitrite as a substrate being upregulated under nitrite limited growth and those using ammonium as a substrate being upregulated during ammonium limitation. Taken together, these results give a first insight in the potential role of the multiple nutrient transporters in regulating transport of substrates and products in and out of the compartmentalized anammox cell.
Project description:RNA was obtained from rear leg muscle of normal and diabetic rats in the presence and absence of oral treatment with vandyl sulfate. Diabetes was induced with streptozotocin and expression profiles were determined using Affymetrix Rat Genechip U34A. The effect of treatment and disease on gene expression was examined. Keywords: vanadium treatment