Detection and identification of huwentoxin-IV interacting proteins by biotin-avidin chemistry combined with mass spectrometry

<div><p>Background : Numerous spider toxins are of interest as tools for neurophysiological research or as lead molecules for the development of pharmaceuticals and insecticides. Direct detection and identification of the interacting proteins of a spider toxin are helpful for its action-mechanism analysis and practical application. The present study employed a combinative strategy for the analysis of interacting proteins of huwentoxin-IV (HWTX-IV), a peptidic neurotoxin from the venom of the spiderSelenocosmia huwena.Results : HWTX-IV was first lightly labeled with biotin under the optimized mild experimental conditions and the toxin labeled with a single biotin group (monobiotinylated HWTX-IV) was demonstrated by electrophysiological experiments to retain its original bioactivity and was used in combination with far-western blotting to detect its interacting proteins. Comparative experiments indicated that some membrane proteins from rat neuromuscular junction preparations bind to monobiotinylated HWTX-IV after being transferred onto a PVDF membrane from the SDS-gel. With capillary high performance liquid chromatography-tandem mass spectrometry, several membrane proteins with which HWTX-IV potentially interacted were identified from the preparations and then bioinformatically analyzed.Conclusions : This work has provided not only a new insight into the action mechanism of HWTX-IV but also a reference technology for the relevant researches.</p></div

Microbial carbohydrate-active enzymes influence soil carbon by regulating the of plant- and fungal-derived biomass decomposition in plateau peat wetlands under differing water conditions

Peatlands are important carbon sinks and water sources in terrestrial ecosystems. It is important to explore their microbial-driven water-carbon synergistic mechanisms to understand the driving mechanisms of carbon processes in peatlands. Based on macrogenomic sequencing techniques, located on the peatland of the eastern margin of the Tibetan Plateau with similar stand and different water conditions, we taken soil properties, microbiome abundance, CAZyme abundance and enzyme gene pathways as the object of study, investigated the characterization of soil microbial carbohydrate-active enzymes (CAZymes) under different water gradients in peatland. According to the results, these three phyla (Chloroflexi, Gemmatimonadetes, and Verrucomicrobia) differed significantly between water gradients. Under dried wetlands, the abundance of CAZymes involved in hemicellulose and glucan degradation increased by 3.0 × 10−5 and 3.0 × 10−6, respectively. In contrast, the abundance of CAZymes involved in chitin degradation decreased by 1.1 × 10−5 (p &lt; 0.05). It highlights that regulating plant- and fungus-derived carbon metabolism processes by soil microorganisms in highland peatlands is a crucial mechanism for their response to water changes. Most plant-derived carbon fractions are regulated by soil enzymes (endo-beta 1,4-xylanase, alpha-L-arabinofuranosidase, and alpha-L-fucosidase) containing CAZymes functional genes. Additional findings in this enzyme gene pathway indicate that water changes that affect soil carbon fractions indirectly influence the three enzyme gene metabolic pathways related to plant carbon sources (the glycolysis/gluconeogenesis, other glycan degradation and amino sugar, and nucleotide sugar metabolism). Overall, this study highlights the significance of microbial CAZymes in highland peatland soil carbon processes and indicates that microbial conversion of plant and fungal biomass carbon is more sensitive to water changes

Allelic effects and variations for key bread-making quality genes in bread wheat using high-throughput molecular markers

We developed and validated high-throughput Kompetitive Allele-Specific PCR (KASP) assays for key genes underpinning bread-making quality, including the wbm gene on chromosome 7AL and over-expressed glutenin Bx7 (Glu-B1al) gene. Additionally, we used pre-existing KASP assay for Sec1 (1B.1R translocation) gene on chromosome 1B. The newly developed KASP assays were compared with gel-based markers for reliability and phenotypically validated in a diversity panel for Mixograph, Rapid Visco Analyzer (RVA) and Mixolab traits. Genotypes carrying the 1B.1R translocation had significantly lower Mixolab parameters than those without the translocation. Similarly, superior effects of the wbm+ and Bx7 alleles on Mixograph and RVA properties and their extremely low frequencies in global wheat collections supported the idea of using these genes for bread-making quality improvement. The allele frequencies of wbm+ and Bx7 were extremely low in historical Chinese and CIMMYT wheat germplasm, but were relatively higher in synthetic hexaploid wheats and their breeding derivatives. In both the Vavilov and Watkins global landrace collections, the frequency of wbm+ was 6.4 and 3.5%, and frequency of Bx7 was 3.2% and 7.0%, respectively. The high-throughput marker resources and large-scale global germplasm screening provided further opportunities to exploit these genes in wheat breeding to enhance bread-making quality

Targeting Inhibition of Accumulation and Function of Myeloid-Derived Suppressor Cells by Artemisinin via PI3K/AKT, mTOR, and MAPK Pathways Enhances Anti-PD-L1 Immunotherapy in Melanoma and Liver Tumors

Despite the remarkable success and efficacy of immune checkpoint blockade (ICB) therapy such as anti-PD-L1 antibody in treating cancers, myeloid-derived suppressor cells (MDSCs) that lead to the formation of the protumor immunosuppressive microenvironment are one of the major contributors to ICB resistance. Therefore, inhibition of MDSC accumulation and function is critical for further enhancing the therapeutic efficacy of anti-PD-L1 antibody in a majority of cancer patients. Artemisinin (ART), the most effective antimalarial drug with tumoricidal and immunoregulatory activities, is a potential option for cancer treatment. Although ART is reported to reduce MDSC levels in 4T1 breast tumor model and improve the therapeutic efficacy of anti-PD-L1 antibody in T cell lymphoma-bearing mice, how ART influences MDSC accumulation, function, and molecular pathways as well as MDSC-mediated anti-PD-L1 resistance in melanoma or liver tumors remains unknown. Here, we reported that ART blocks the accumulation and function of MDSCs by polarizing M2-like tumor-promoting phenotype towards M1-like antitumor one. This switch is regulated via PI3K/AKT, mTOR, and MAPK signaling pathways. Targeting MDSCs by ART could significantly reduce tumor growth in various mouse models. More importantly, the ART therapy remarkably enhanced the efficacy of anti-PD-L1 immunotherapy in tumor-bearing mice through promoting antitumor T cell infiltration and proliferation. These findings indicate that ART controls the functional polarization of MDSCs and targeting MDSCs by ART provides a novel therapeutic strategy to enhance anti-PD-L1 cancer immunotherapy

Comparison of low molecular weight glutenin subunits identified by SDS-PAGE, 2-DE, MALDI-TOF-MS and PCR in common wheat

Low-molecular-weight glutenin subunits (LMW-GS) play a crucial role in determining end-use quality of common wheat by influencing the viscoelastic properties of dough. Four different methods - sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), two-dimensional gel electrophoresis (2-DE, IEF × SDS-PAGE), matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and polymerase chain reaction (PCR), were used to characterize the LMW-GS composition in 103 cultivars from 12 countries

Recent Advances in Research on Widow Spider Venoms and Toxins

Widow spiders have received much attention due to the frequently reported human and animal injures caused by them. Elucidation of the molecular composition and action mechanism of the venoms and toxins has vast implications in the treatment of latrodectism and in the neurobiology and pharmaceutical research. In recent years, the studies of the widow spider venoms and the venom toxins, particularly the α-latrotoxin, have achieved many new advances; however, the mechanism of action of the venom toxins has not been completely clear. The widow spider is different from many other venomous animals in that it has toxic components not only in the venom glands but also in other parts of the adult spider body, newborn spiderlings, and even the eggs. More recently, the molecular basis for the toxicity outside the venom glands has been systematically investigated, with four proteinaceous toxic components being purified and preliminarily characterized, which has expanded our understanding of the widow spider toxins. This review presents a glance at the recent advances in the study on the venoms and toxins from the Latrodectus species

Flood risk assessment using the CV-TOPSIS method for the Belt and Road Initiative: an empirical study of Southeast Asia

Instruction The countries along the Belt and Road Initiative remain high exposure and vulnerability to climate extremes. Southeast Asia, a significant part of the Belt and Road Initiative, suffers a lot from flood disasters. This study assessed the flood disaster risk from 1990–2015 in all 11 Southeast Asian countries. A model integrating the coefficient of variation approach and the Technique for Order Preference by Similarity to Ideal Solution method was introduced to analyze the flood disaster data. Considering that populations living in areas where elevation is below 5 m and land area where elevation is below 5 m have reached 11.86% and 3.54% (2015), respectively, the two indicators were opted for to propose new metrics for flood disaster risk assessment.Outcomes: Our findings show that the flood disaster risk in Southeast Asia appeared very high during most of the study period. Indonesia had an extremely high flood disaster risk, followed by Vietnam, whereas Laos, Malaysia, Brunei, and Timor Leste had lower flood risks. The model introduced in this paper is quite simple and easy to understand, providing accessible flood risk information for decision makers.Conclusion: The results we obtained have practical implications for land use and investment activities in Southeast Asia

Finding missing diversity from synonyms of Haplopteris (Pteridaceae)

Although taxonomists target the remote wild regions to discover new species, taxa lacking a comprehensive and modern systematic treatment may be the new hotspot for biodiversity discovery. The development of molecular systematics integrated with microscopic observation techniques has greatly improved the ability of taxonomists to identify species correctly. Vittaria centrochinensis Ching ex J.F. Cheng, regarded as a synonym of Haplopteris fudzinoi (Makino) E.H.Crane, remained hidden from the eyes of fern taxonomists for more than 20 years. Herein, we collected several population samples of V. centrochinensis by performing molecular phylogenetic analysis of five cpDNA regions (rbcL, atpA, matK, ndhF, and trnL-trnF) and through micromophological observation of specimens which differs from H. fudzinoi by lamina width and exospores. Considering the differences in morphology, geographical range, and genetic distance between these two species, we formally recognized V. centrochinensis as an authentic species and proposed a new combination Haplopteris centrochinensis (Ching ex J.F.Cheng) Y.H.Yan, Z.Y.Wei & X.C.Zhang, comb. nov. Our findings demonstrate that several taxa in synonyms are missing, and nowadays taxonomy should also include re-evaluation of the past taxonomy

Isolation and Preliminary Characterization of Proteinaceous Toxins with Insecticidal and Antibacterial Activities from Black Widow Spider (L. tredecimguttatus) Eggs

The eggs of black widow spider (L. tredecimguttatus) have been demonstrated to be rich in toxic proteinaceous components. The study on such active components is of theoretical and practical importance. In the present work, using a combination of multiple biochemical and biological strategies, we isolated and characterized the proteinaceous components from the aqueous extract of the black widow spider eggs. After gel filtration of the egg extract, the resulting main protein and peptide peaks were further fractionated by ion exchange chromatography and reversed-phase high performance liquid chromatography. Two proteinaceous components, named latroeggtoxin-III and latroeggtoxin-IV, respectively, were purified to homogeneity. Latroeggtoxin-III was demonstrated to have a molecular weight of about 36 kDa. Activity analysis indicated that latroeggtoxin-III exhibited neurotoxicity against cockroaches but had no obvious effect on mice, suggesting that it is an insect-specific toxin. Latroeggtoxin-IV, with a molecular weight of 3.6 kDa, was shown to be a broad-spectrum antibacterial peptide, showing inhibitory activity against all five species of bacteria tested, with the highest activity against Staphylococcus aureus. Finally, the implications of the proteinaceous toxins in egg protection and their potential applications were analyzed and discussed