Project description:The field of epitranscriptomics is growing in importance, with chemical modification of RNA being associated with a wide variety of biological phenomena. Mass spectrometry (MS) enables the identification of modified RNA residues within their sequence contexts, by using analogous approaches to shotgun proteomics. We have developed a free and open-source database search engine for RNA MS data, called NucleicAcidSearchEngine (NASE), as part of the OpenMS software framework. NASE allows the reliable identification of (modified) RNA sequences from LC-MS/MS data in a high-throughput fashion. For this validation dataset, we prepared two samples of an in vitro-transcribed yeast lncRNA (NME1, 340 nt long), one of which was treated with an RNA methyltransferase (NCL1) catalyzing the 5-methylcytidine (m5C) modification. These samples were subsequently digested with an RNA endonuclease (RNase) to generate oligonucleotide sequences of a length amenable to mass spectrometry.
Project description:The field of epitranscriptomics is growing in importance, with chemical modification of RNA being associated with a wide variety of biological phenomena. Mass spectrometry (MS) enables the identification of modified RNA residues within their sequence contexts, by using analogous approaches to shotgun proteomics. We have developed a free and open-source database search engine for RNA MS data, called NucleicAcidSearchEngine (NASE), as part of the OpenMS software framework. NASE allows the reliable identification of (modified) RNA sequences from LC-MS/MS data in a high-throughput fashion. For this validation dataset, we prepared two samples of an in vitro-transcribed yeast lncRNA (NME1, 340 nt long), one of which was treated with an RNA methyltransferase (NCL1) catalyzing the 5-methylcytidine (m5C) modification. These samples were subsequently digested with an RNA endonuclease (RNase) to generate oligonucleotide sequences of a length amenable to mass spectrometry.
Project description:BackgroundCommon bean (Phaseolus vulgaris L.) is a thermophilic crop, and exposure to cold stress can significantly impact their yield and quality. To elucidate the impact of cold stress on cold-tolerant 'Wei Yuan' (WY) and cold-sensitive 'Bai Bu Lao' (BBL) of common bean, the mechanism of cold tolerance was studied by physiological and biochemical and multi-omics analysis.ResultsIn this study, lower relative conductivity and higher malondialdehyde content after cold stress endowed 'WY' seedlings with cold tolerance. A total of 11,837 differentially expressed genes (DEGs) and 923 differential metabolites (DEMs) were identified by transcriptome and metabolomics analysis. Joint analysis showed that under cold stress, DEGs and DEMs in common beans are extensively engaged in sugar, amino acid and isoflavonoid biosynthesis, flavone and flavonol biosynthesis, and plant hormone signal translation, especially related to isoflavone biosynthesis. In addition, it was also found that bHLH and MYB family transcription factors may be involved in the cold signal transduction of common bean.ConclusionsThe above results will provide a theoretical basis for the cold tolerance mechanism of common beans and provide help for the screening of cold-tolerant resources of common beans.Clinical trial numberNot applicable.
Project description:Arctic Mesorhizobium sp. N33 isolated from nodules of Oxytropis arctobia in Canada's eastern Arctic has a growth temperature range from 0 °C to 30 °C and is a well-known cold-adapted rhizobia. The key molecular mechanisms underlying cold adaptation in Arctic rhizobia remains totally unknown. Since the concentration and contents of metabolites are closely related to stress adaptation, we applied GC-MS and NMR to identify and quantify fatty acids and water soluble compounds possibly related to low temperature acclimation in strain N33. Bacterial cells were grown at three different growing temperatures (4 °C, 10 °C and 21 °C). Cells from 21 °C were also cold-exposed to 4°C for different times (2, 4, 8, 60 and 240 minutes). We identified that poly-unsaturated linoleic acids 18:2 (9, 12) & 18:2 (6, 9) were more abundant in cells growing at 4 or 10 °C, than in cells cultivated at 21 °C. The mono-unsaturated phospho/neutral fatty acids myristoleic acid 14:1(11) were the most significantly overexpressed (45-fold) after 1 hour of exposure to 4 °C. As reported in the literature, these fatty acids play important roles in cold adaptability by supplying cell membrane fluidity, and by providing energy to cells. Analysis of water-soluble compounds revealed that isobutyrate, sarcosine, threonine and valine were more accumulated during exposure to 4 °C. These metabolites might play a role in conferring cold acclimation to strain N33 at 4 °C, probably by acting as cryoprotectants. Isobutyrate was highly upregulated (19.4-fold) during growth at 4 °C, thus suggesting that this compound is a precursor for the cold-regulated fatty acids modification to low temperature adaptation.
Project description:Cold stress is one of the major abiotic stresses limiting tea production. The planting of cold-resistant tea cultivars is one of the most effective measures to prevent chilling injury. However, the differences in cold resistance between tea cultivars remain unclear. In the present study, we perform a transcriptomic and metabolomic profiling of Camellia sinensis var. "Shuchazao" (cold-tolerant, SCZ) and C. sinensis var. assamica "Yinghong 9" (cold-sensitive, YH9) during cold acclimation and analyze the correlation between gene expression and metabolite biosynthesis. Our results show that there were 51 differentially accumulated metabolites only up-regulated in SCZ in cold-acclimation (CA) and de-acclimation (DA) stages, of which amino acids accounted for 18%. The accumulation of L-arginine and lysine in SCZ in the CA stage was higher than that in YH9. A comparative transcriptomic analysis showed an enrichment of the amino acid biosynthesis pathway in SCZ in the CA stage, especially "arginine biosynthesis" pathways. In combining transcriptomic and metabolomic analyses, it was found that genes and metabolites associated with amino acid biosynthesis were significantly enriched in the CA stage of SCZ compared to CA stage of YH9. Under cold stress, arginine may improve the cold resistance of tea plants by activating the polyamine synthesis pathway and CBF (C-repeat-binding factor)-COR (cold-regulated genes) regulation pathway. Our results show that amino acid biosynthesis may play a positive regulatory role in the cold resistance of tea plants and assist in understanding the cold resistance mechanism differences among tea varieties.
Project description:Genome-wide identification of transcription factor (TF) binding sites in the genome of the fission yeast Schizosaccharomyces pombe. The ChIP-nexus method was used. TFs included were: Cbf11-TAP and Cbf12-TAP (and their DBM mutants with impaired DNA binding), TAP-Mga2, and Fkh2-TAP (as an irrelevant control TF). IPs from an untagged WT strain were also analyzed. Cbf11-related IPs were performed from exponential cultures, while Cbf12-related IPs were performed from stationary cultures. YES complex medium was used for all cultivations.
Project description:Immune aplastic anemia (AA) is a life-threatening bone marrow (BM) failure disorder driven by an autoimmune T cell attack against the hematopoietic stem and progenitor cells (HSPCs). However, the autoantigen targets and the role of other immune cells are unknown. Here, by combining scRNA+TCRαβ-seq, TCRβ-seq, flow cytometry and plasma cytokine profiling of >250 patients with AA, >250 patients with other hematological disorders and >1,000 healthy controls, we identify NK cells and CD8+ TEMRA cells expressing NK receptors with AA-associated TCRB-seq motifs as the most dysregulated immune cell populations in AA BM. Functional co-culture experiments with scRNA-TCRαβ-seq readout utilizing primary HSPCs and immune cells (in total 55 conditions) provide evidence that NK cells alone cannot kill HSPCs, but sensitize them to CD8+ T cell mediated killing. Furthermore, HSPCs induce strong activation of T cell clones with CD8+ TEMRA NK-like phenotype and AA-associated TCR motifs. To conclude, our results reveal convergent evolution of innate and adaptive immune cells in AA, where NK cells support CD8+ T cell mediated autoimmunity.
Project description:The apicomplexan parasite Toxoplasma gondii forms bradyzoite-containing tissue cysts that cause chronic and drug-tolerant infections. However, current in vitro models do not allow long-term culture of these cysts to maturity. Here, we developed a human myotube-based in vitro culture model of functionally mature tissue cysts that are orally infectious to mice and tolerate exposure to a range of antibiotics and temperature stresses. Metabolomic characterization of purified cysts reveals global changes that comprise increased levels of amino acids and decreased abundance of nucleobase- and tricarboxylic acid cycle-associated metabolites. In contrast to fast replicating tachyzoite forms of T. gondii these tissue cysts tolerate exposure to the aconitase inhibitor sodium fluoroacetate. Direct access to persistent stages of T. gondii under defined cell culture conditions will be essential for the dissection of functionally important host-parasite interactions and drug evasion mechanisms. It will also facilitate the identification of new strategies for therapeutic intervention.
Project description:The pathogen and host factors that contribute to the establishment of foot-and-mouth disease virus (FMDV) persistence are currently not understood. Using primary bovine soft palate multilayers in combination with RNA sequencing, we analyzed the transcriptional responses during acute and persistent FMDV infection.