24 research outputs found

    Stability and asynchrony of local communities but less so diversity increase regional stability of Inner Mongolian grassland

    Full text link
    Extending knowledge on ecosystem stability to larger spatial scales is urgently needed because present local-scale studies are generally ineffective in guiding management and conservation decisions of an entire region with diverse plant communities. We investigated stability of plant productivity across spatial scales and hierarchical levels of organization and analyzed impacts of dominant species, species diversity, and climatic factors using a multisite survey of Inner Mongolian grassland. We found that regional stability across distant local communities was related to stability and asynchrony of local communities. Using only dominant instead of all-species dynamics explained regional stability almost equally well. The diversity of all or only dominant species had comparatively weak effects on stability and synchrony, whereas a lower mean and higher variation of precipitation destabilized regional and local communities by reducing population stability and synchronizing species dynamics. We demonstrate that, for semi-arid temperate grassland with highly uneven species abundances, the stability of regional communities is increased by stability and asynchrony of local communities and these are more affected by climate rather than species diversity. Reduced amounts and increased variation of precipitation in the future may compromise the sustainable provision of ecosystem services to human well-being in this region

    Loss of Abhd5 Promotes Colorectal Tumor Development and Progression by Inducing Aerobic Glycolysis and Epithelial-Mesenchymal Transition

    Get PDF
    How cancer cells shift metabolism to aerobic glycolysis is largely unknown. Here, we show that deficiency of a/b-hydrolase domain-containing 5 (Abhd5), an intracellular lipolytic activator that is also known as comparative gene identification 58 (CGI-58), promotes this metabolic shift and enhances malignancies of colorectal carcinomas (CRCs). Silencing of Abhd5 in normal fibroblasts induces malignant transformation. Intestine-specific knockout of Abhd5 in ApcMin/+ mice robustly increases tumorigenesis and malignant transformation of adenomatous polyps. In colon cancer cells, Abhd5 deficiency induces epithelial-mesenchymal transition by suppressing the AMPKa-p53 pathway, which is attributable to increased aerobic glycolysis. In human CRCs, Abhd5 expression falls substantially and correlates negatively with malignant features. Our findings link Abhd5 to CRC pathogenesis and suggest that cancer cells develop aerobic glycolysis by suppressin

    Macrophage CGI-58 Deficiency Activates ROS-Inflammasome Pathway to Promote Insulin Resistance in Mice

    Get PDF
    SummaryOvernutrition activates a proinflammatory program in macrophages to induce insulin resistance (IR), but its molecular mechanisms remain incompletely understood. Here, we show that saturated fatty acid and lipopolysaccharide, two factors implicated in high-fat diet (HFD)-induced IR, suppress macrophage CGI-58 expression. Macrophage-specific CGI-58 knockout (MaKO) in mice aggravates HFD-induced glucose intolerance and IR, which is associated with augmented systemic/tissue inflammation and proinflammatory activation of adipose tissue macrophages. CGI-58-deficient macrophages exhibit mitochondrial dysfunction due to defective peroxisome proliferator-activated receptor (PPAR)γ signaling. Consequently, they overproduce reactive oxygen species (ROS) to potentiate secretion of proinflammatory cytokines by activating NLRP3 inflammasome. Anti-ROS treatment or NLRP3 silencing prevents CGI-58-deficient macrophages from oversecreting proinflammatory cytokines and from inducing proinflammatory signaling and IR in the cocultured fat slices. Anti-ROS treatment also prevents exacerbation of inflammation and IR in HFD-fed MaKO mice. Our data thus establish CGI-58 as a suppressor of overnutrition-induced NLRP3 inflammasome activation in macrophages

    Biotic stability mechanisms in Inner Mongolian grassland

    Full text link
    Biotic mechanisms associated with species diversity are expected to stabilize communities in theoretical and experimental studies but may be difficult to detect in natural communities exposed to large environmental variation. We investigated biotic stability mechanisms in a multi-site study across Inner Mongolian grassland characterized by large spatial variations in species richness and composition and temporal fluctuations in precipitation. We used a new additive-partitioning method to separate species synchrony and population dynamics within communities into different species-abundance groups. Community stability was independent of species richness but was regulated by species synchrony and population dynamics, especially of abundant species. Precipitation fluctuations synchronized population dynamics within communities, reducing their stability. Our results indicate generality of biotic stability mechanisms in natural ecosystems and suggest that for accurate predictions of community stability in changing environments uneven species composition should be considered by partitioning stabilizing mechanisms into different species-abundance groups

    The Role of ZNF275/AKT Pathway in Carcinogenesis and Cisplatin Chemosensitivity of Cervical Cancer Using Patient-Derived Xenograft Models

    No full text
    Zinc finger protein 275 (ZNF275) is a C2H2-type transcription factor that is localized on chromosome Xq28. Whether ZNF275 participates in modulating the biological behaviors of cervical cancer has not been determined to our knowledge. The present study employed CCK-8, BrdU, flow cytometry, and a transwell assay to investigate the cell viability, proliferation, apoptosis, migration, and invasion of cervical cancer cells. The application of Western blotting and immunohistochemistry (IHC) aims to assess ZNF275 protein expression and identify the signaling pathway relevant to ZNF275-mediated effects on cervical cancer. The therapeutic impact of the combined therapy of the AKT inhibitor triciribine and cisplatin was evaluated on cervical cancer patient-derived xenograft (PDX) models expressing high ZNF275. The current research illustrated that cervical cancer tissue exhibited a higher expression of ZNF275 in contrast to the surrounding normal cervical tissue. The downregulation of ZNF275 suppressed cell viability, migration, and invasion, and facilitated the apoptosis of SiHa and HeLa cells via weakening AKT/Bcl-2 signaling pathway. Moreover, triciribine synergized with cisplatin to reduce cell proliferation, migration, and invasion, and enhanced the apoptosis of SiHa cells expressing high ZNF275. In addition, the combination treatment of triciribine and cisplatin was more effective in inducing tumor regression than single agents in cervical cancer PDX models expressing high ZNF275. Collectively, the current findings demonstrated that ZNF275 serves as a sufficiently predictive indicator of the therapeutic effectiveness of the combined treatment of triciribine and cisplatin on cervical cancer. Combining triciribine with cisplatin greatly broadens the therapeutic options for cervical cancer expressing high ZNF275, but further research is needed to confirm these results

    Biotic stability mechanisms in Inner Mongolian grassland

    No full text
    Electronic supplementary material is available online at https://doi.org/10.6084/m9.figshare.c.4969886.Biotic mechanisms associated with species diversity are expected to stabilize communities in theoretical and experimental studies but may be difficult to detect in natural communities exposed to large environmental variation. We investigated biotic stability mechanisms in a multi-site study across Inner Mongolian grassland characterized by large spatial variations in species richness and composition and temporal fluctuations in precipitation. We used a new additive-partitioning method to separate species synchrony and population dynamics within communities into different species-abundance groups. Community stability was independent of species richness but was regulated by species synchrony and population dynamics, especially of abundant species. Precipitation fluctuations synchronized population dynamics within communities, reducing their stability. Our results indicate generality of biotic stability mechanisms in natural ecosystems and suggest that for accurate predictions of community stability in changing environments uneven species composition should be considered by partitioning stabilizing mechanisms into different species-abundance groups

    Crystallographic Data Collection Using a Multilayer Monochromator on an Undulator Beamline at the Shanghai Synchrotron Radiation Facility

    No full text
    To resolve photons hungry for weak diffraction samples by the crystallographic method, a double-multilayer monochromator (DMM) was employed on an undulator beamline (BL17UM) at the Shanghai Synchrotron Radiation Facility (SSRF) to provide a focused sub-micron beam with high brightness for macromolecular crystallography experiments. High-quality crystallographic datasets from model protein crystal samples were collected and processed by an existing crystallographic program for structure solution and refinement. The data quality was compared with datasets from a normal silicon crystal monochromator to evaluate the bandwidth of the DMM effect on these crystallographic data. This experiment demonstrates that multilayer optics on an undulator beamline may play a valuable role in satisfying the demands of structure-related research, which requires novel methods
    corecore