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Biology subjects

Xi, Q.

Publications and source records attributed to Xi, Q..

7 recordsLinked to original sources

Terrestrial ecosystems enhance root zones in response to intensified drought

Adaptation of ecosystems root zones to climate change critically affects drought resilience and vegetation productivity. However, a global quantitative assessment of this mechanism is missing. Therefore, we analyzed observation-based data and found that the global average root zone water storage capacity (SR) increased by 11%, from 182 to 201 mm in 1982-2020. This increase amounts to 1657 billion m3 over the past four decades, affecting hydrological and ecological processes worldwide. SR increased in 9 out of 12 land cover types, while three relatively dry types experienced decreasing trends, potentially suggesting the crossing of ecosystem tipping points. Our results underscore the importance of considering root zone dynamics while analysing floods, droughts and carbon sequestration under climate change.

ecology↗

Cell-free multi-omics analysis reveals tumor status-informative signatures in gastrointestinal cancer patients' plasma

During cancer development, hosts tumorigenesis and immune signals are released to and informed by circulating molecules, like cell-free DNA (cfDNA) and RNA (cfRNA) in blood. However, these two kinds of molecules are still not systematically compared in gastrointestinal cancer. Here, we profiled 4 types of cell-free omics data from colorectal and stomach cancer patients, and assayed 15 types of genomic, epi-genomic, and transcriptomic variations. First, we demonstrated that the multi-omics data were more capable of detecting cancer genes than the single-omics data, where cfRNAs were more sensitive and informative than cfDNAs in terms of detection ratio, variation type, altered number, and enriched functional pathway. Moreover, we revealed several peripheral immune signatures that were suppressed in cancer patients and originated from specific circulating and tumor-microenvironment cells. Particularly, we defined a {gamma}{delta}-T-cell score and a cancer-associated-fibroblast (CAF) score using the cfRNA-seq data of 143 cancer patients. They were informative of clinical status like cancer stage, tumor size, and survival. In summary, our work reveals the cell-free multi-molecular landscape of colorectal and stomach cancer, and provides a potential monitoring utility in blood for the personalized cancer treatment.

systems biology↗

Piezo mechanosensory channels regulate centrosome integrity

Piezo1 and 2 are evolutionarily conserved mechanosensory cation channels known to function on the cell surface by responding to external pressure and transducing a mechanically activated Ca2+ current. Here we show that both Piezo1 and 2 also exhibit concentrated intracellular localization at centrosomes. Both Piezo1 and 2 loss-of-function and Piezo1 activation by the small molecule Yoda1 produced supernumerary centrosomes due to inappropriate centriole disengagement. Using a centrosome-localized GCaMP Ca2+-sensitive reporter, we show that perturbations in Piezo modulate Ca2+ local concentration at centrosomes. We designed a photoactivable Yoda1 analog (caged-Yoda1) and revealed that its photoactivation specifically at centrosomes leads to rapid premature centriole disengagement within minutes. We identified the sorting nexin Snx5, which is involved in endocytic uptake and trafficking, as a protein-interactor with the conserved Piezo C-terminal domain, and Snx5 also co-localizes with Piezo1 and 2 at centrosomes. Moreover, inhibition of Polo-like-kinase 1 (PLK1) abolishes Yoda1-induced centriole disengagement. Collectively, these data suggest that Piezo1 and 2 in pericentrosomal endosomes control centrosome integrity, likely by maintaining local Ca2+ within a defined range through mechanotransduction of cell intrinsic forces from microtubules.

cell biology↗

Co3O4 /PAn Magnetic Nanoparticle-Modified Electrochemical Immunosensor for Azocyclotin

In the current study, for rapid detection of azocylotin residues in agricultural products, the Co3O4/PAn nanoparticles modified electrochemical immunosensor was generated successfully. Azocylotin-BSA artificial antigen coupling to the surface of the working electrode coated with the Co3O4/PAn nanoparticles thin-layer, the competitive inhibition reaction is launched between the azocylotin in the samples and the azocylotin coupled on the electrode with the azocylotin monoclonal antibodies in the test system. The antigen-antibody reaction signal conductive amplified by the coupled silver nanoparticles, and then the electrolytic current in the reaction system was detected. After establishing basic detection system, a series of optimization including the concentration of immobilized membrane optimization, electrode surface coated material composition optimization, selection of buffer, coupling antigen concentration optimization and anti-antibody label optimization will be done. Subsequently, the concentrations of azocylotin in samples of standards, orange and apple were tested, and the results indicated that this immune sensor has good sensitivity and high accuracy. The research could provide the reference for the research, development and application of sensors to realize rapid detection of pesticide residues in agricultural products.

biochemistry↗

Microbial diversity in raw milk and Sayram Ketteki from southern of Xinjiang, China

Raw milk and fermented milk are rich in microbial resources, which are essential for the formation of texture, flavor and taste. In order to gain a deeper knowledge of the bacterial and fungal community diversity in local raw milk and home-made yogurts from Sayram town, Baicheng county, Akesu area, southern of Xinjiang, China,30 raw milk and 30 home-made yogurt samples were collected and experiment of high-throughput sequencing was implemented.The results of experiments revealed the species of fungi in raw milk was the most, and the species of bacteria in fermented milk was the least.Based on principal component analysis (PCA), it was found that the bacterial and fungal community structure differed in samples from two types of dairy products.And the presence of 15 bacterial and 12 fungal phyla, comprising 218 bacterial and 495 fungal genera respectively, among all samples. Firmicutes and Ascomycota,Lactobacillus and Candida were the predominant phyla and genera of bacteria and fungi, respectively. The results indicated that the microbial community of raw milk differs from home-made yogurts due to sampling location and manufacturing process. The study suggested that high-throughput sequencing could provide a better understanding of microbiological diversity as well as lay a theoretical foundation for selecting beneficial microbial resources from this natural yogurt.

bioinformatics↗

α-ketoglutaric acid stimulates muscle hypertrophy and fat loss through OXGR1-dependent adrenal activation

Beneficial effects of resistance exercise on metabolic health and particularly muscle hypertrophy and fat loss are well established, but the underlying chemical and physiological mechanisms are not fully understood. Here we identified a myometabolite-mediated metabolic pathway that is essential for the beneficial metabolic effects of resistance exercise in vivo. We showed that substantial accumulation of the tricarboxylic acid cycle intermediate -ketoglutaric acid (AKG) is a metabolic signature of resistance exercise performance. Interestingly, human plasma AKG level is also negatively correlated with BMI. Pharmacological elevation of circulating AKG induces muscle hypertrophy, brown adipose tissue (BAT) thermogenesis, and white adipose tissue (WAT) lipolysis in vivo. We further found that AKG stimulates the adrenal release of adrenaline through 2-oxoglutarate receptor 1 (OXGR1) expressed in adrenal glands. Finally, by using both loss-of-function and gain-of-function mouse models, we showed that OXGR1 is essential for AKG-mediated exercise-induced beneficial metabolic effects. These findings reveal an unappreciated mechanism for the salutary effects of resistance exercise, using AKG as a systemically-derived molecule for adrenal stimulation of muscle hypertrophy and fat loss.

molecular biology↗

The effect of dietary ginseng polysaccharide supplementation on the immune responses involved in porcine milk-derived esRNAs

Ginseng and its polysaccharides (GPS) have been well known as an immune modulator. This study was conducted to investigate the effects of dietary supplemental GPS on the immune responses involved in sows milk-derived exosomal shuttle RNAs (esRNAs) using RNA-Seq and miRNA-Seq. Of the 213 identified miRNA types, a total of 26 conserved miRNAs were differently expressed in response to GPS supplementation, including 10 up-regulated and 16 down-regulated miRNAs in GPS feeding group. In addition, exosomal transcriptome analysis identified 14,696 protein-coding genes in sows milk exosomes, and 283 genes with 204 and 79 candidates showing up and down-regulation were significantly responded to GPS supplementation. Integrated analysis of each differently expressed miRNA with significantly expressed genes further revealed the presence of 51 highly conserved miRNA-gene interactions that were annotated to be related to immunoregulatory functions. This work provided an important advance in the functional identification of dietary GPS supplementation and more fundamental information about how GPS promoted the immune response and healthy growth of the infant from mothers at molecular levels.

genomics↗