通讯机构：
[Guixiang Yuan] H;[Wei Li] R;Hunan Provincial Key Laboratory of Rural Ecosystem Health in Dongting Lake Area, Ecology Department, College of Resources and Environment, Hunan Agricultural University, Changsha, China<&wdkj&>Research Institute of Ecology & Environmental Sciences, Nanchang Institute of Technology, Nanchang, 330099, China
摘要：
Extreme precipitation events caused by climate change leads to large variation of nitrogen input to aquatic ecosystems. Our previous study demonstrated the significant effect of different ammonium pulse patterns (differing in magnitude and frequency) on submersed macrophyte growth based on six plant morphological traits. However, how connectivity among plant traits responds to nitrogen pulse changes, which in turn affects plant performance, has not yet been fully elucidated. The response of three common submersed macrophytes (Myriophyllum spicatum, Vallisneria natans and Potamogeton maackianus) to three ammonium pulse patterns was tested using plant trait network (PTN) analysis based on 18 measured physiological and morphological traits. We found that ammonium pulses enhanced trait connectivity in PTN, which may enable plants to assimilate ammonium and/or mitigate ammonium toxicity. Large input pulses with low frequency had stronger effects on PTNs compared to low input pulses with high frequency. Due to the cumulative and time-lagged effect of the plant response to the ammonium pulse, there was a profound and prolonged effect on plant performance after the release of the pulse. The highly connected traits in PTN were those related to biomass allocation (e.g., plant biomass, stem ratio, leaf ratio and ramet number) rather than physiological traits, while phenotype-related traits (e.g., plant height, root length and AB ratio) and energy storage-related traits (e.g., stem starch) were least connected. V. natans showed clear functional divergence among traits, making it more flexible to cope with unfavorable habitats (i.e., high input pulses with low frequencies). M. spicatum with high RGR revealed strong correlations among traits and thus supported nitrogen accumulation from favourable environments (i.e., low input pulses with high frequencies). Our study highlights the responses of PTN for submerged macrophytes to ammonium pulses depends on their intrinsic metabolic rates, the magnitude, frequency and duration of the pulses, and our results contribute to the understanding of the impact of resource pulses on the population dynamics of submersed macrophytes within the context of global climate change.
摘要：
Omega-6 polyunsaturated fatty acids (ω6-PUFAs), such as γ-linolenic acid (GLA), dihomo-γ-linolenic acid (DGLA) and arachidonic acid (ARA), are indispensable nutrients for human health. Harnessing the lipogenesis pathway of Yarrowia lipolytica creates a potential platform for producing customized ω6-PUFAs. This study explored the optimal biosynthetic pathways for customized production of ω6-PUFAs in Y. lipolytica via either the Δ6 pathway from Mortierella alpina or the Δ8 pathway from Isochrysis galbana. Subsequently, the proportion of ω6-PUFAs in total fatty acids (TFAs) was effectively increased by bolstering the provision of precursors for fatty acid biosynthesis and carriers for fatty acid desaturation, as well as preventing fatty acid degradation. Finally, the proportions of GLA, DGLA and ARA synthesized by customized strains accounted for 22.58%, 46.65% and 11.30% of TFAs, and the corresponding titers reached 386.59, 832.00 and 191.76mg/L in shake-flask fermentation, respectively. This work provides valuable insights into the production of functional ω6-PUFAs.
通讯机构：
[Tiean Zhou; Tiean Zhou Tiean Zhou Tiean Zhou] C;[Linhong Deng; Linhong Deng Linhong Deng Linhong Deng] H;Hunan Provincial Engineering Technology Research Center for Cell Mechanics and Function Analysis, Changsha, Hunan, 410128 China<&wdkj&>Institute of Biomedical Engineering and Health Sciences, Changzhou University, Changzhou, Jiangsu, 213164 China<&wdkj&>College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha, Hunan, 410128 China<&wdkj&>Hunan Provincial Engineering Technology Research Center for Cell Mechanics and Function Analysis, Changsha, Hunan, 410128 China
摘要：
Double resonator piezoelectric cytometry (DRPC) is developed to simultaneously quantify cells’ generated forces ΔS and viscoelastic moduli G′, G″ of a population of isolated single cells or cells with different cell‐cell contacts adhered to the AT and BT cut quartz crystals of the same frequency and morphology by measuring their respective changes in resonant frequency and motional resistance. Abstract Cell mechanics is closely associated with cellular structure and function. However, the inability to measure both cellular force and viscoelasticity of statistically significant number of cells noninvasively remains a challenge for quantitative characterizations of various cellular functions and practical applications. Here a double resonator piezoelectric cytometry (DRPC), using AT and BT cut quartz crystals of the same frequency and surface morphology is developed to simultaneously quantify the cells‐generated forces (ΔS) and viscoelastic moduli (G′, G″) of a population of isolated single cells or cells with different degrees of cell‐cell interactions in a non‐invasive and real time manner. DRPC captures the dynamic mechanical parameters ΔS and G′, G″ during the adhesions of human umbilical vein endothelial cells (HUVECs) under different ligand densities of adhesion molecules fibronectin or Arg‐Gly‐Asp (RGD) modified on the gold surfaces of 9 MHz AT and BT cut quartz crystals, and different seeding densities of HUVECs. It is found that both the ligand density and cell seeding density affect the magnitudes of ΔS and G′, G″ and their correlations are revealed for the first time by DRPC. The validity of DRPC is further verified by mechanical changes of the cells in response to treatments with cytoskeleton regulators.
摘要：
Auxin is a well-known important phytohormone in plant that plays vital roles in almost every development process throughout plant lifecycle. However, the effect of auxin on the metabolism of chlorophyll, one of the most important pigments involved in the photosynthesis, was intertwined and the underlying mechanism remained to be explored. Here, we found the auxin-defective yuc2 yuc6 double mutant displayed dark-green leaf color with higher chlorophyll content than wildtype, suggesting a negative regulatory role of auxin in chlorophyll biosynthesis. The chloroplast number and structure in mesophyll cells were altered and the photosynthetic efficiency was improved in yuc2 yuc6. In addition, the chlorophyll level was significantly improved during seedling de-etiolation in yuc2 yuc6 mutant, and decreased dramatically under IAA treatment, confirming the inhibitory role of auxin in chlorophyll biosynthesis. The analyses of gene expression in mature leaves and de-etiolation seedlings suggested that auxin suppressed the expression of many chlorophyll biosynthesis genes, especially PROTOCHLOROPHYLLIDE OXIDOREDUCTASE A (PORA) and GENOMES UNCOUPLED 5 (GUN5). Yeast-one-hybrid and luciferase assays demonstrated that the AUXIN RESPONSE FACTOR 2 (ARF2) and ARF7 bind to the promoter of PORA and GUN5 to suppress their expression with the help of INDOLE-3-ACETIC ACID14 (IAA14). Collectively, our research explicitly unraveled the direct inhibitory role of auxin in chlorophyll biosynthesis, and provided new insight into the interplay between auxin signaling and chlorophyll metabolism.
摘要：
BACKGROUND AND AIMS: Non-alcoholic fatty liver disease (NAFLD) has become a significant cause of chronic liver disease in developed countries, as a result of the worldwide trend of obesity and associated metabolic syndrome. Obesity and high-fat diet (HFD) are very common in patients with NAFLD. However, how to screen out key differentially expressed genes (DEGs) is a challenging task. The purpose of this study is to study the screen of key genes and pathways of HFD on the formation process of non-alcoholic fatty liver through network pharmacological analysis. METHODS: In this study, 173 genes associated with NAFLD were collected from the Gene Expression Omnibus (GEO) database. To find significant genes and pathways, combine network clustering analysis, topology analysis, and pathway analysis. RESULTS: The results showed that there were four key signaling pathways related to HFD, including complement cascade, Atorvastatin ADME, Asthma and Aflatoxin activation and detoxification. In addition, we identified six representative key genes, including Ccl5, Tlr2, Cd274, Cxcl10, Cxcl9 and Cd74, and screened three intersecting genes in Mus musculus and Homo sapiens sample, including C3, F2 and C7. CONCLUSIONS: In conclusion, our study constructed the NAFLD gene regulatory network of C57BL/6J mice for the first time and jointly analyzed the Mus musculus samples and Homo sapiens samples. It provides new insights for identifying potential biomarkers and valuable therapeutic clues, and puts forward a new method for web-based research. These findings may provide potential targets for early diagnosis, effective therapy and prognostic markers of NAFLD.
通讯机构：
[Junhua Chen] N;National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou, 510650, China
关键词：
CRISPR-Cas12a;Catalytic hairpin assembly;DNAzyme;Heavy metal ions;Intelligent sensing;Logic gate
摘要：
We successfully constructed several molecular logic gates using heavy metal ions as inputs based on catalytic hairpin assembly (CHA) and CRISPR-Cas12a. The corresponding DNAzymes were used to recognize heavy metal ions (Hg(2+), Cd(2+), Pb(2+), and Mn(2+)). The specific cleavage between heavy metal ions and DNAzymes leads to the release of the trigger DNA, which can be used to activate CHA through logic computation. The CHA-generated DNA duplexes contain the protospacer adjacent motifs (PAM) sequence, which can be distinguished by CRISPR-Cas12a. The hybridization interactions between the duplexes and gRNA will activate the trans-cleavage capability of Cas12a, which can cleave the single-stranded DNA (ssDNA) reporter. The separation of the fluorescence group and quench group in ssDNA will generate a high fluorescence signal for readout. Using Hg(2+) and Cd(2+) as the two inputs, several basic logic gates were constructed, including OR, AND, and INHIBT. Using Hg(2+), Cd(2+), Pb(2+), and Mn(2+) as the four inputs, cascaded logic gates were further fabricated. With the advantages of scalability, versatility, and logic computing capability, our proposed molecular logic gates can provide an intelligent sensing system for heavy metal ions monitoring.
通讯机构：
[Zhihui Yuan] C;College of Chemistry and Bioengineering, Hunan University of Science and Engineering, 130 Yangzitang Road, Lingling, Yongzhou 425199, China
摘要：
Human activities have led to elevated levels of selenium (Se) in the environment, which poses a threat to ecosystems and human health. Stenotrophomonas sp. EGS12 (EGS12) has been identified as a potential candidate for the bioremediation of repair selenium-contaminated environment because of its ability to efficiently reduce Se(IV) to form selenium nanospheres (SeNPs). To better understand the molecular mechanism of EGS12 in response to Se(IV) stress, a combination of transmission electron microscopy (TEM), genome sequencing techniques, metabolomics and transcriptomics were employed. The results indicated that under 2mM Se(IV) stress, 132 differential metabolites (DEMs) were identified, and they were significantly enriched in metabolic pathways such as glutathione metabolism and amino acid metabolism. Under the Se(IV) stress of 2mM, 662 differential genes (DEGs) involved in heavy metal transport, stress response, and toxin synthesis were identified in EGS12. These findings suggest that EGS12 may respond to Se(IV) stress by engaging various mechanisms such as forming biofilms, repairing damaged cell walls/cell membranes, reducing Se(IV) translocation into cells, increasing Se(IV) efflux, multiplying Se(IV) reduction pathways and expelling SeNPs through cell lysis and vesicular transport. The study also discusses the potential of EGS12 to repair Se contamination alone and co-repair with Se-tolerant plants (e.g. Cardamine enshiensis). Our work provides new insights into microbial tolerance to heavy metals and offers valuable information for bio-remediation techniques on Se(IV) contamination.
通讯机构：
[Shitou Xia] H;Hunan Provincial Key Laboratory of Phytohormones and Growth Development, College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha 410128, China<&wdkj&>Author to whom correspondence should be addressed.
关键词：
B. napus;GYF domain;S. sclerotiorum;infection response;synteny analysis
摘要：
GYF (glycine-tyrosine-phenylalanine)-domain-containing proteins, which were reported to participate in many aspects of biological processes in yeast and animals, are highly conserved adaptor proteins existing in almost all eukaryotes. Our previous study revealed that GYF protein MUSE11/EXA1 is involved in nucleotide-binding leucine-rich repeat (NLR) receptor-mediated defense in Arabidopsis thaliana. However, the GYF-domain encoding homologous genes are still not clear in other plants. Here, we performed genome-wide identification of GYF-domain encoding genes (GYFs) from Brassica napus and its parental species, Brassica rapa and Brassica oleracea. As a result, 26 GYFs of B. napus (BnaGYFs), 11 GYFs of B. rapa (BraGYFs), and 14 GYFs of B. oleracea (BolGYFs) together with 10 A. thaliana (AtGYFs) were identified, respectively. We, then, conducted gene structure, motif, cis-acting elements, duplication, chromosome localization, and phylogenetic analysis of these genes. Gene structure analysis indicated the diversity of the exon numbers of these genes. We found that the defense and stress responsiveness element existed in 23 genes and also identified 10 motifs in these GYF proteins. Chromosome localization exhibited a similar distribution of BnaGYFs with BraGYFs or BolGYFs in their respective genomes. The phylogenetic and gene collinearity analysis showed the evolutionary conservation of GYFs among B. napus and its parental species as well as Arabidopsis. These 61 identified GYF domain proteins can be classified into seven groups according to their sequence similarity. Expression of BnaGYFs induced by Sclerotinia sclerotiorum provided five highly upregulated genes and five highly downregulated genes, which might be candidates for further research of plant-fungal interaction in B. napus.
作者机构：
[Li, Yuchen; Chen, Long; Mi, Baobin; He, Jiangnan; Wu, Fangfang; Zhou, Zhi] Hunan Agr Univ, Coll Agron, Coll Biosci & Biotechnol, Hunan Engn Res Ctr Biochar,Sch Chem & Mat Sci, Changsha 410128, Hunan, Peoples R China.;[Mi, Baobin] Hunan Acad Agr Sci, Res Inst Vegetables, Changsha 410125, Peoples R China.
通讯机构：
[Fangfang Wu] S;School of Chemistry and Materials Science, Hunan Engineering Research Center for Biochar, College of Agronomy, College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha, Hunan 410128, China
摘要：
In this study, functionalized banana peel biochar (BPB) was prepared by microwave-assisted pyrolysis for the first time to investigate its adsorption to malachite green (MG) dye. Adsorption experiments showed that the maximum adsorption capacity of BPB500 and BPB900 to malachite green reached 1790.30 and 2297.83 mg.g(-1) within 120 min. The adsorption behaviour was well-fitted by the pseudo-second-order kinetic model and Langmuir isotherm model, and Delta G(0) < 0, Delta H-0 > 0, indicated that the adsorption process was endothermic and spontaneous, dominated by chemisorption. The adsorption mechanism of MG dye on BPB included hydrophobic interaction, hydrogen bonding, pi-pi interaction, n-pi interaction, and ion exchange. Meanwhile, through regeneration tests, simulated wastewater treatment experiments, and cost calculations, it was found that BPB has great potential for practical applications. This work demonstrated that microwave-assisted pyrolysis is a viable low-cost approach for producing excellent sorbents from biomass, and banana peel is a promising feedstock to prepare biochar for dye removal.
