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Poly[(butylene adipate)‐co‐terephthalate] (PBAT) is currently the most widely used and versatile petroleum‐based fully biodegradable polyester, drawing extensive attention from researchers. However, the high production cost of PBAT restricts its widespread application. Currently, incorporating fillers into PBAT materials is considered the most effective approach to reduce production costs, with thermoplastic starch recognized as the optimal filler for PBAT base materials. Nevertheless, the low mechanical strength of thermoplastic starch significantly compromises the performance of PBAT base materials. In this study, thermoplastic starch with higher mechanical strength was prepared by partially substituting commonly used glycerol with a higher molecular weight sorbitol as the plasticizer. The enhanced thermoplastic starch was then used as a filler for PBAT materials, leading to the fabrication of PBAT‐based blend films with high starch content. Mechanical property tests revealed a 52.2% and 65.3% increase of tensile strength in the transverse and longitudinal directions, respectively, when sorbitol partially replaced glycerol as the plasticizer for thermoplastic starch. Scanning electron microscopy results demonstrated improved dispersion of thermoplastic starch particles in PBAT when sorbitol and glycerol were used together. Meanwhile, the thermal performance and stability of PBAT were not significantly affected by the thermoplastic starch filling. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Adaptive evolution following colonization can affect the impact of invasive species. The fall webworm (FWW) invaded China 40 years ago through a single introduction event involving a severe bottleneck and subsequently diverged into two genetic groups. The well‐recorded invasion history of FWW, coupled with a clear pattern of genetic divergence, provides an opportunity to investigate whether there is any sign of adaptive evolution following the invasion. Based on genome‐wide SNPs, we identified genetically separated western and eastern groups of FWW and correlated spatial variation in SNPs with geographical and climatic factors. Geographical factors explained a similar proportion of the genetic variation across all populations compared with climatic factors. However, when the two population groups were analysed separately, environmental factors explained more variation than geographical factors. SNP outliers in populations of the western group had relatively stronger response to precipitation than temperature‐related variables. Functional annotation of SNP outliers identified genes associated with insect cuticle protein potentially related to desiccation adaptation in the western group and genes associated with lipase biosynthesis potentially related to temperature adaptation in the eastern group. Our study suggests that invasive species may maintain the evolutionary potential to adapt to heterogeneous environments despite a single invasion event. The molecular data suggest that quantitative trait comparisons across environments would be worthwhile. [ABSTRACT FROM AUTHOR]

Course‐based Undergraduate Research Experiences (CUREs) integrate active, discovery‐based learning into undergraduate curricula, adding tremendous value to Biochemistry and Molecular Biology (BMB) education. There are multiple challenges in transforming a research project into a CURE, such as the readiness of students, the time commitment of the instructor, and the productivity of the research. In this article, we report a CURE course developed and offered in the University of Massachusetts Amherst BMB Department since 2018 that addresses these challenges. Our CURE focuses on fungal effectors which are proteins secreted by a destructive pathogenic fungus Fusarium oxysporum, one of the top five most devastating plant pathogens. By studying this group of proteins, students are connected to real‐world problems and participate in the search for potential solutions. A 3‐week "standard Boot Camp" is implemented to help students familiarize themselves with all basic techniques and boost their confidence. Next, molecular cloning, a versatile technique with modularity and repeatability, is used as the bedrock of the course. Our past 5 years of experience have confirmed that we have developed a novel and feasible CURE protocol. Measurable progress documented by students who took this course includes stimulated active learning and increased career trajectory to pursue hypothesis‐based research to address societal needs. In addition, data generated through the course advance ongoing lab research. Collectively, we encourage the implementation of CURE among research‐intensive faculty to provide a more inclusive research experience to undergraduate students, an important element in predicting career success. [ABSTRACT FROM AUTHOR]

BACKGROUND: Field control of pest thrips mainly relies on insecticides, but the toxicity of insecticides can vary among thrips species and populations. In this study, we examined the susceptibility of multiple field populations of two thrips pests, Frankliniella occidentalis, and Thrips palmi, that often co‐occur on vegetables, to nine insecticides belonging to seven subgroups. RESULTS: The highest level of variation in susceptibility among F. occidentalis populations was for spinetoram (73.92 fold difference between most resistant and most susceptible population), followed by three neonicotinoids (8.06–15.99 fold), while among T. palmi populations, it was also for spinetoram (257.19 fold), followed by emamectin benzoate, sulfoxaflor, and acetamiprid (23.64–45.50 fold). These findings suggest evolved resistance to these insecticides in some populations of the two thrips. One population of F. occidentalis had a particularly high level of resistance overall, being the most resistant for five of the nine insecticides tested. Likewise, a population of T. palmi had high resistance to all nine insecticides, again suggesting the evolution of resistance to multiple chemicals. For F. occidentalis, the LC95 values of most populations were higher than the field‐recommended dosage for all insecticides except chlorfenapyr and emamectin benzoate. For several T. palmi populations, the LC95 values also tended to be higher than recommended dosages, except in the case of emamectin benzoate and spinetoram. CONCLUSIONS: Our study found interspecific and intraspecific variations in the susceptibility of two thrips to nine insecticides and multiple resistance in some populations, highlighting the need for ongoing monitoring and resistance management. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Background: Thrips pests cause increasing damage to crops around the world. Widespread usage of some insecticides against thrips has now led to the evolution of resistance to several active ingredients, and new insecticides are required. This study examined the toxicity of the novel insecticide broflanilide to multiple populations of several thrips pests. Results: Bioassays showed that thrips populations had LC50 values ranging from 0.5 to almost 300 mg·L−1. A population of Frankliniella occidentalis had the highest LC50 value at 290.63 mg·L−1, while a population of Echinothrips americanus had the lowest LC50 value at 0.51 mg L−1. LC50 values among seven populations of Thrips palmi ranged from 2.5689 to 23.6754 mg·L−1, indicating intraspecific variation in toxicity. In this species, the toxicity of broflanilide was relatively higher in adults than in larvae. More than 90% of eggs of T. palmi could not develop into larvae when treated with 5–50 mg L−1 broflanilide. Compared to five commonly used insecticides, broflanilide showed relatively high toxicity to T. palmi. Field control tests with T. palmi showed that control efficacy (from 90.44% to 93.14%) was maintained from day three to day 14 after treatment with 22.5 and 45 ga.i hm−1 broflanilide. Conclusion: Broflanilide is potentially a useful insecticide for controlling Thrips hawaiiensis, Frankliniella intonsa, Megalurothrips usitatus. E. americanus, and some populations of T. palmi. However, the variation in toxicity of this insecticide to different species, populations, and developmental stages indicates that target species and life stages may need to be carefully considered. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

In the last decade, polymerization‐induced self‐assembly (PISA) has emerged to be a quite popular technique for preparing a variety of nanoassembly structures in a selective solvent. As a special technique of PISA, polymerization‐induced cooperative assembly (PICA) is believed to be able to produce more variable nanostructures and its ways of regulation seem more flexible. The process of PICA is studied systematically with a simulation method for discovering possible ways of regulation of morphologies. We find that the existence of solvophobic homopolymers yields a 'chain growth retarding effect', which effectively slows down the reaction kinetics of the polymerization. Besides proving the transition from lower‐order morphologies to higher‐order morphologies as reported in experiments, we also find a novel transition from higher‐order morphologies to lower‐order morphologies, as a result of the self‐adaptation behavior of the system. For the first time, we demonstrate that this behavior is able to be well described as a kind of inverse flip‐flop process of vesicle structures to thermodynamically stable micelle structures. We also find that the obvious contrast of length between the solvophilic macro‐chain transfer agents and solvophobic blocks is beneficial to the emergence of plentiful kinds of structures. The results of this study are helpful for understanding the crucial factors for precisely regulating the morphologies in PICA, as well as guiding the way to improve experimental technologies. © 2021 Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]

Summary: Fusaric acid (FSA) is a phytotoxin produced by several Fusarium species and has been associated with plant disease development, although its role is still not well understood.Mutation of key genes in the FSA biosynthetic gene (FUB) cluster in Fusarium oxysporum f. sp. cubense tropical race 4 (Foc TR4) reduced the FSA production, and resulted in decreased disease symptoms and reduced fungal biomass in the host banana plants.When pretreated with FSA, both banana leaves and pseudostems exhibited increased sensitivity to Foc TR4 invasion. Banana embryogenic cell suspensions (ECSs) treated with FSA exhibited a lower rate of O2 uptake, loss of mitochondrial membrane potential, increased reactive oxygen species (ROS) accumulation, and greater nuclear condensation and cell death. Consistently, transcriptomic analysis of FSA‐treated ECSs showed that FSA may induce plant cell death through regulating the expression of genes involved in mitochondrial functions.The results herein demonstrated that the FSA from Foc TR4 functions as a positive virulence factor and acts at the early stage of the disease development before the appearance of the fungal hyphae in the infected tissues. [ABSTRACT FROM AUTHOR]

Objective The mechanism of Schisandrin B on the proliferation and migration of airway smooth muscle cells (ASMCs) in asthmatic rats was explored. Methods SD rats were divided into three groups: control (group 1), model (group 2) and model + Schisandrin B (group 3). miR-150 and lnc RNA BCYRN1 levels were measured by qRT- PCR. The combination of BCYRN1 and miR-150 was detected by RNA pull down. ASMCs' viability/proliferation/migration were examined by WST-1 assay and 24-well Transwell system. Results Schisandrin B up-regulated miR-150 expression and down-regulated BCYRN1 expression in sensitized rats. Schisandrin B reversed the expression of miR-150 and BCYRN1 in MV-treated ASMCs. In addition, Schisandrin B inhibited the viability, proliferation and migration of MV-induced ASMCs. We also found miR-150 inhibited BCYRN1 expression which was proved by experiments using ASMCs transfected with miR-150 inhibitor. Conclusion Schisandrin B increased miR-150 expression and decreased BCYRN1, and BCYRN1 expression was inhibited by miR-150, which indicated that Schisandrin B could regulate BCYRN1 through miR-150. [ABSTRACT FROM AUTHOR]

Formae speciales (ff.spp.) of the fungus Fusarium oxysporum are often polyphyletic within the species complex, making it impossible to identify them on the basis of conserved genes. However, sequences that determine host-specific pathogenicity may be expected to be similar between strains within the same forma specialis. Whole genome sequencing was performed on strains from five different ff.spp. (cucumerinum, niveum, melonis, radicis-cucumerinum and lycopersici). In each genome, genes for putative effectors were identified based on small size, secretion signal, and vicinity to a “miniature impala” transposable element. The candidate effector genes of all genomes were collected and the presence/ absence patterns in each individual genome were clustered. Members of the same forma specialis turned out to group together, with cucurbit-infecting strains forming a supercluster separate from other ff.spp. Moreover, strains from different clonal lineages within the same forma specialis harbour identical effector gene sequences, supporting horizontal transfer of genetic material. These data offer new insight into the genetic basis of host specificity in the F. oxysporum species complex and show that (putative) effectors can be used to predict host specificity in F. oxysporum. [ABSTRACT FROM AUTHOR]

Head blight caused by Fusarium graminearum threatens world-wide wheat production, resulting in both yield loss and mycotoxin contamination., We reconstructed the global F. graminearum gene regulatory network (GRN) from a large collection of transcriptomic data using Bayesian network inference, a machine-learning algorithm. This GRN reveals connectivity between key regulators and their target genes. Focusing on key regulators, this network contains eight distinct but interwoven modules. Enriched for unique functions, such as cell cycle, DNA replication, transcription, translation and stress responses, each module exhibits distinct expression profiles., Evolutionarily, the F. graminearum genome can be divided into core regions shared with closely related species and variable regions harboring genes that are unique to F. graminearum and perform species-specific functions. Interestingly, the inferred top regulators regulate genes that are significantly enriched from the same genomic regions ( P < 0.05), revealing a compartmentalized network structure that may reflect network rewiring related to specific adaptation of this plant pathogen., This first-ever reconstructed filamentous fungal GRN primes our understanding of pathogenicity at the systems biology level and provides enticing prospects for novel disease control strategies involving the targeting of master regulators in pathogens. The program can be used to construct GRNs of other plant pathogens. [ABSTRACT FROM AUTHOR]

Airway smooth muscle cell (ASMC) was known to involve in the pathophysiology of asthma. Schisandrin B was reported to have anti-asthmatic effects in a murine asthma model. However, the molecular mechanism involving in the effect of Schisandrin B on ASMCs remains poorly understood. Sprague-Dawley rats were divided into three groups: rats as the control (Group 1), sensitized rats (Group 2), sensitized rats and intragastric-administrated Schisandrin B (Group 3). The expression of miR-135a and TRPC1 was detected in the rats from three groups. Platelet-derived growth factor (PDGF)-BB was used to induce the proliferation of isolated ASMCs, and the expression of miR-135a and TRPC1 was detected in PDGF-BB-treated ASMCs. Cell viability was examined in ASMCs transfected with miR-135a inhibitor or si-TRPC1. The expression of TRPC1 was examined in A10 cells pretreated with miR-135a inhibitor or miR-135a mimic. In this study, we found that Schisandrin B attenuated the inspiratory and expiratory resistances in sensitized rats. Schisandrin B upregulated the mRNA level of miR-135a and decreased the expression of TRPC1 in sensitized rats. In addition, Schisandrin B reversed the expression of miR-135a and TRPC1 in PDGF-BB-induced ASMCs. Si-TRPC1 abrogated the increasing proliferation of ASMCs induced by miR-135a inhibitor. We also found that miR-135a regulated the expression of TRPC1 in the A10 cells. These results demonstrate that Schisandrin B inhibits the proliferation of ASMCs via miR-135a suppressing the expression of TRPC1. [ABSTRACT FROM AUTHOR]

The cyclic adenosine monophosphate-protein kinase A (c AMP- PKA) pathway is a central signalling cascade that transmits extracellular stimuli and governs cell responses through the second messenger cAMP. The importance of cAMP signalling in fungal biology has been well documented and the key conserved components, adenylate cyclase ( AC) and the catalytic subunit of PKA ( CPKA), have been functionally characterized. However, other genes involved in this signalling pathway and their regulation are not well understood in filamentous fungi. Here, we performed a comparative transcriptomics analysis of AC and CPKA mutants in two closely related fungi: Fusarium graminearum ( Fg) and F. verticillioides ( Fv). Combining available Fg transcriptomics and phenomics data, we reconstructed the Fg cAMP signalling pathway. We developed a computational program that combines sequence conservation and patterns of orthologous gene expression to facilitate global transcriptomics comparisons between different organisms. We observed highly correlated expression patterns for most orthologues (80%) between Fg and Fv. We also identified a subset of 482 (6%) diverged orthologues, whose expression under all conditions was at least 50% higher in one genome than in the other. This enabled us to dissect the conserved and unique portions of the cAMP- PKA pathway. Although the conserved portions controlled essential functions, such as metabolism, the cell cycle, chromatin remodelling and the oxidative stress response, the diverged portions had species-specific roles, such as the production and detoxification of secondary metabolites unique to each species. The evolution of the cAMP- PKA signalling pathway seems to have contributed directly to fungal divergence and niche adaptation. [ABSTRACT FROM AUTHOR]

In this study, we report a histidine-based fluorescence probe for Cu2+ and Hg2+, in which the amino group and imino group were modified by two common protective groups, 9-fluorenylmethoxycarbonyl and trityl group, respectively. In a water/methanol mixed solution, the probe displayed a selective fluorescence 'turn-off' response to Cu2+ when the ratio of CH3OH/H2O was higher than 1:1. Specifically, when the solvent is changed to 1:1 methanol/water, the 304 nm fluorescence peak is enhanced, while the 317 nm peak is weakened, upon addition of either Cu2+ or Hg2+ ions. The mechanism for such distinct responses of the probe to Cu2+ and Hg2+ was further clarified by using NMR and molecular simulation. The experiment results indicated that the polarity of solvent could influence the coordination mode of 1 with Cu2+ and Hg2+, and control the fluorescence response as a 'turn-off' or ratiometric probe. [ABSTRACT FROM AUTHOR]