Project description:Guar gum consists mainly of galactomannan, and constitutes the endosperm of guar seeds that acts as a reserve polysaccharide for germination. Due to its molecular structure and physical properties, this biopolymer has been considered as one of the most important and widely used gums in industry. However, for many of these applications this (hemi-)cellulosic structure needs to be modified or (partially) depolymerized in order to customize and improve its physicochemical properties. In this study, transcriptome was employed to decipher the complete enzymatic arsenal for guar gum depolymerization by Aspergillus niger.
Project description:Non-alcoholic fatty liver disease (NAFLD) is rapidly becoming the most common liver disease worldwide, yet the pathogenesis of NAFLD is only partially understood. Here, we investigated the role of the gut bacteria in NAFLD by stimulating the gut bacteria via feeding mice the fermentable dietary fiber guar gum and suppressing the gut bacteria via chronic oral administration of antibiotics. Guar gum feeding profoundly altered the gut microbiota composition, in parallel with reduced diet-induced obesity and improved glucose tolerance. Strikingly, despite reducing adipose tissue mass and inflammation, guar gum enhanced hepatic inflammation and fibrosis, concurrent with markedly elevated plasma and hepatic bile acid levels. Consistent with a role of elevated bile acids in the liver phenotype, treatment of mice with taurocholic acid stimulated hepatic inflammation and fibrosis. In contrast to guar gum, chronic oral administration of antibiotics effectively suppressed the gut bacteria, decreased portal secondary bile acid levels, and attenuated hepatic inflammation and fibrosis. Neither guar gum or antibiotics influenced plasma lipopolysaccharide levels. In conclusion, our data indicate a causal link between changes in gut microbiota and hepatic inflammation and fibrosis in a mouse model of NAFLD, possibly via alterations in bile acids.
Project description:The first GSSM of V. vinifera was reconstructed (MODEL2408120001). Tissue-specific models for stem, leaf, and berry of the Cabernet Sauvignon cultivar were generated from the original model, through the integration of RNA-Seq data. These models have been merged into diel multi-tissue models to study the interactions between tissues at light and dark phases.
Project description:<p>The practice of intercropping young walnut orchards with soybeans has emerged as a promising approach within the framework of sustainable agricultural management. However, the precise impacts of soybean intercropping on nitrogen metabolism in walnut roots remain insufficiently elucidated. This study systematically investigated the regulatory mechanisms of nitrogen metabolism in the walnut-soybean intercropping system using metabolomics and RNA-seq analysis. By determination relevant indicators, we observed that the dry matter accumulation of both aboveground tissues and roots in intercropped walnuts was significantly higher than that in monocropped walnuts, with the root system had a distinct vertical growth advantage. The nitrogen content in aboveground portions during dormancy and in roots during the hard kernel stage and dormancy was markedly elevated compared to monoculture systems. Metabolomics analysis revealed that differential metabolites in walnut under intercropping are significantly enriched in the carbon-nitrogen metabolic pathways and nitrogen transmembrane transport pathways. RNA-seq analysis identified 3,978 differentially expressed genes (DEGs), with significantly enrichment in the “nitrogen utilization” pathway. Furthermore, integrated analysis indicated that nitrogen metabolites may play a significant role in the walnut intercropping system. Key genes associated with nitrogen metabolism (NR, NIR, GOGAT, GDH, NRT, and AMT) exhibited significant alterations under the intercropping system. Enzyme activity validation demonstrated that intercropping substantially enhanced the activities of GS, GOGAT, and other enzymes, thereby strengthening the GS/GOGAT cycle responsible for converting inorganic nitrogen into organic nitrogen. This study confirms that walnut-soybean intercropping promotes dry matter accumulation and nitrogen allocation by activating root carbon-nitrogen metabolic pathways and the expression of nitrogen metabolism-related genes. These findings provide critical metabolic and transcriptional evidence supporting the sustainable development of intercropping systems in dryland orchards.</p>