African swine fever virus (ASFV) is a giant and complex DNA virus that causes a highly contagious and often lethal swine disease for which no vaccine is available. Using an optimized image ...reconstruction strategy, we solved the ASFV capsid structure up to 4.1 angstroms, which is built from 17,280 proteins, including one major (p72) and four minor (M1249L, p17, p49, and H240R) capsid proteins organized into pentasymmetrons and trisymmetrons. The atomic structure of the p72 protein informs putative conformational epitopes, distinguishing ASFV from other nucleocytoplasmic large DNA viruses. The minor capsid proteins form a complicated network below the outer capsid shell, stabilizing the capsid by holding adjacent capsomers together. Acting as core organizers, 100-nanometer-long M1249L proteins run along each edge of the trisymmetrons that bridge two neighboring pentasymmetrons and form extensive intermolecular networks with other capsid proteins, driving the formation of the capsid framework. These structural details unveil the basis of capsid stability and assembly, opening up new avenues for African swine fever vaccine development.
Lactococcus lactis, a lactic acid bacterium, has been widely used in the fermented dairy products. The acid tolerance of L. lactis is of great importance to food fermentation and probiotic ...applications. As the first barrier of bacteria, the cell wall has a protective effect on strains under many stress conditions, whereas the regulatory mechanism has rarely been reported. Here, based on the transcription analysis of 9 cell wall or membrane-related genes of L. lactis F44 under acid stress, the transcription levels of DACB, DLTD, YLBA, HRTA, WP_080613266.1 (1610), and ERFK genes were significantly increased. We constructed 9 overexpressing strains with the cell wall or membrane-related genes, respectively. It was demonstrated that the survival rates under acid stress of DACB, DLTD, and ERFK were significantly higher than that of wild-type F44. To investigate the regulatory mechanism, a DNA pull-down assay was used to identify the transcriptional regulators of these 3 genes. It was discovered that the 2-component system (TCS) transcriptional regulator TCSR7 bound to the upstream region of DLTD involved in the teichoic acid (TA) alanylation. The combination was confirmed through an electrophoretic mobility shift assay in vitro. Reverse-transcription quantitative PCR results indicated that TCSR7 upregulated the expression of DLTD gene. In addition, the transcription level of TCSR7 increased approximately 1.8-fold (log2 fold change) under acidic conditions. In summary, this study found that TCSR7 was induced by acid stress to upregulate the transcription level of the DLT operon genes, which might increase the positive charge on the cell membrane surface to increase the acid tolerance of the strain. This study lays the foundation for the regulatory mechanism of TA alanylation under acid stress.
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•EGCG + LTA/βCD inclusion complexes prevented EGCG digestion in vitro.•EGCG + LTA/βCD increased EGCG bioaccessibility and antioxidant activity.•EGCG + LTA/βCD increased gut ...micro-diversity and lipid metabolism genera in vivo.•EGCG + LTA/βCD enhanced the lipid-lowering and weight loss effects of EGCG in vivo.
Epigallocatechin-3-gallate (EGCG) and L-theanine (LTA), which are active ingredients in green tea, can inhibit fat accumulation; however, EGCG bioavailability is <5%. Here, we aimed to improve EGCG bioavailability and efficacy by preparing EGCG + LTA/β-cyclodextrin (βCD) inclusion complexes by freeze-drying EGCG + LTA at their mass ratio (5:1) in green tea. Physicochemical characterisation revealed that the supramolecular EGCG + LTA/βCD inclusion complexes had distinct crystal structures formed via intermolecular hydrogen bonding. The inclusion complexes prevented simulated EGCG digestion in vitro while increasing its bioaccessibility and antioxidant activity (p < 0.05). In rats fed a high-fat diet, EGCG + LTA/βCD inclusion complexes significantly increased gut microflora diversity and the abundance of lipid metabolism-related genera but decreased the abundance of EGCG catabolism-related genera. Furthermore, the inclusion complexes significantly enhanced the lipid-lowering and weight loss effects of EGCG in vivo (p < 0.05), likely by improving gut microflora and EGCG bioavailability.
The protein levels in a diet are correlated with immunity but the long-term intake of excessive protein can compromise various aspects of health. L-theanine regulates immunity and protein metabolism; ...however, how its regulatory immunity effects under a high-protein diet are unclear. We used proteomics, metabonomics, and western blotting to analyze the effects of diets with different protein levels on immune function in rats to determine the role of L-theanine in immunity under a high-protein diet. The long-term intake of high-protein diets (≥40% protein) promoted oxidative imbalance and inflammation. These were alleviated by L-theanine. High-protein diets inhibited peroxisome proliferator-activated receptor (PPAR)α expression through the interleukin (IL)-6/signal transducer and activator of transcription (STAT)3 pathway and mediated inflammation. L-theanine downregulated anti-fatty acid-binding protein 5 (FABP5), inhibited the IL-6/STAT3 axis, and reduced high-protein diet-induced PPARα inhibition. Therefore, L-theanine alleviates the adverse effects of high-protein diets via the FABP5/IL-6/STAT3/PPARα pathway and regulates the immunity of normally fed rats through the epoxide hydrolase (EPHX)2/nuclear factor-kappa B inhibitor (IκB)α/triggering receptor expressed on myeloid cells (TREM)1 axis.
•Long-term intake of high protein diets of 40% protein or higher will cause oxidative imbalance, inflammatory reactions, and liver damage, which is not conducive to immunity.•LTA can inhibit the oxidative imbalance and inflammatory reaction caused by high protein diet, and alleviate liver injury.•LTA can inhibit the inflammatory response through the FABP5-IL6-STAT3-PPARα pathway.•LTA can reduce the harmful effects of high protein diet on immunity by regulating the production of inflammatory factors.
Trehalase plays a significant role in various physiological processes in insects. In this study, we cloned and characterized a soluble trehalase gene (HaTreh-1) and a membrane-bound trehalase gene ...(HaTreh-2) from Helicoverpa armigera, a serious polyphagous pest of crops. HaTreh-1 contained an open reading frame of 1716bp that encodes a protein of 572 amino acids. HaTreh-2 has an open reading frame of 1938bp, encoding a protein of 646 amino acids. Sequence alignment and phylogenetic analysis of the two putative proteins revealed that HaTreh-1 and HaTreh-2 belong to soluble and membrane-bound trehalase groups, respectively. Quantitative real-time PCR (qPCR) analyses of the spatiotemporal expression pattern of HaTreh in H. armigera revealed that HaTreh-1 was expressed mainly in the midgut, with lower expression in the integument and head, Malpighian tubules, trachea, and fat body. The expression levels of HaTreh-2 were detected in all 6 tissues, and HaTreh-2 was mainly expressed in the midgut and head. Expression of HaTreh-1 was higher throughout the larval stages, but lower on days 1 and 2 of the pupal stage. Expression of HaTreh-2 was higher during the 4th- and 5th-instar larval stages. Taken together, these results suggest that HaTreh-1 and HaTreh-2 have different functions in various developmental stages and tissues.
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•Two trehalase genes (HaTreh-1 and HaTreh-2) from H. armigera were cloned.•The bioinformation of HaTrehs was analyzed.•Multiple sequence alignment and phylogenetic trees of Trehs were built.•The expression patterns in various tissues were analyzed.•The expression patterns during developmental process were analyzed.
In this study, malondialdehyde (MDA), relative conductivity (RC), superoxide anion (O₂ㆍ-), hydrogen peroxide (H₂O₂), superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), ascorbate peroxidase ...(APX) as well as ascorbic acid (AsA), glutation (GSH) and carotenoid (Car) were analyzed in plants under drought condition to investigate the enzymatic and non-enzymatic antioxidant defense mechanisms of leaves and petals, respectively. Two different drought resistance marigold cultivars (Tagetes erecta L. cv. Chokdee and Tagetes erecta L. cv. Discovery) treated with 6-day drought stress were used at early flowering stage. Results indicated that drought treatment increased MDA, RC, O₂ㆍ- and H₂O₂ contents in the two cultivars, especially in drought-sensitive cultivar 'Discovery'. In contrast, 'Chokdee' had higher level antioxidative enzyme activities and more non-enzymatic antioxidants than those in 'Discovery'. SOD, POD, CAT, APX activities and non-enzymatic antioxidants (GSH and AsA) in the leaves and petals were increased at the beginning treatment, and decreased later. The activity of CAT in leaves and petals, APX in petals and AsA in petals on day 6 after treatment were lower than those in control, while Car in the two cultivars decreased consistently during drought stress treatment. In addition, all the antioxidant enzyme activities in the leaves were higher than those in petals, but AsA and GSH were accumulated at lower levels in leaves than those in petals of the both cultivars. Furthermore, significant linear relationships were found between antioxidative enzymes and reactive oxygen species (ROS), as well as in non-enzymatic antioxidants and ROS. In conclusion, drought tolerance of 'Chokdee' was correlated with eliminating the O₂ㆍ- and H₂O₂ and maintaining lower lipid peroxidation as well as higher membrane stability by increasing activities of antioxidative enzymes and the amount of non-enzymatic antioxidants. Furthermore, different drought response mechanisms were involved in leaves and petals of marigold under drought stress.
Impacts of road construction on plant diversity in Taibai Mountain National Forest Park Zhang Changgui, Yangling Vocational and Technical College, Yangling (China), Department of Tourism and Management; Li Jingxia, Northwest Agriculture and Forestry University, Yangling (China),College of Forestry; Fang Dafeng, Yangling Vocational and Technical College, Yangling (China), Department of Ecological and Environmental Engineering
Xi bei nong lin ke ji da xue xue bao.Zi ran ke xue ban,
20/Mar., Volume:
40, Issue:
3
Journal Article
明晰道路建设对太白山国家森林公园植物多样性的影响程度，为植物多样性及植被的恢复提供依据。以公园红桦坪到下板寺之间道路两侧的植被为研究对象，运用典型样地法，在道路的边缘设置干扰样地3块，分别在3块干扰样地同侧水平距离50 m或近无人干扰处设置对照样地3块，样地面积为20 m×20 m，在每块样地中又各设5个5 m×5 m的灌木样方和5个1 m×1 ...m的草本样方，对干扰样地和对照样地的植物群落进行对比调查，从物种组成、重要值、α多样性指数和相似性4方面进行统计与分析。与对照样地相比，干扰样地中总体物种数量仅少1种，为57种；乔木、灌木、草本中各物种的组成差异较大，有些物种在干扰样地中消失，但又有新的物种侵入；各物种的重要值变化无明显规律；物种多样性指数稍降低，其中乔木物种的多样性指数明显降低但不显著(P＞0.05)，灌木物种的Brillouin指数（H）显著降低，草本物种的Shannon-Wiener指数（H′）、Brillouin指数（H）、Simpson指数（D）显著升高；物种相似性总体表现为干扰样地之间相似，对照样地之间相似。道路建设对太白山国家森林公园植物多样性造成了明显影响。
The research is conducted to have a clear understanding of the impacts of road construction on plant diversity in Taibai Mountain National Forest Park and provide basis for the restoration of plant diversity and vegetation. This study employs the method of special quadrats to carry out comparative research on the plant groups along the road from Xiaban Temple to Honghua Level Ground in Taibai Mountain National Forest park. Three disturbed quadrats are set at the edge of the road and three control quadrats are set at the
Establishment of cell line expressing miRNA let-7c and regulation on classical swine fever virus Zhang Xu, Northwest Agriculture and Forestry University, Yangling (China), College of Veterinary Medicine; Zhang Yanming, Northwest Agriculture and Forestry University, Yangling (China), College of Veterinary Medicine; Zhang Qian, Northwest Agriculture and Forestry University, Yangling (China), College of Veterinary Medicine
Xi bei nong lin ke ji da xue xue bao.Zi ran ke xue ban,
Dec. 2010, Volume:
38, Issue:
12
Journal Article
构建含有let-7c前体基因的重组质粒pGene-pre-let-7c，建立稳定表达猪miRNA let-7c细胞株，研究let-7c对猪瘟病毒(CSFV)复制的调控作用。利用RNA22软件筛选出CSFV基因组3′-UTR ...潜在的let-7c结合位点，PCR扩增出let-7c前体片段，连接到表达载体pGenesil-1.1-dBm2上,构建重组质粒pGene-pre-let-7c，采用脂质体法将重组质粒转染猪脐静脉血管内皮细胞（SUVEC），经G418抗性压力筛选获得阳性细胞株。对获得的阳性细胞株进行接毒试验，检测CSFV的复制情况。用MTT比色法检测阳性细胞的增殖情况。成功扩增出let-7c前体基因，并构建了pGene-pre-let-7c重组质粒。重组质粒转染SUVEC细胞后筛选获得了稳定表达let-7c的细胞株。let-7c可下调CSFV在细胞中的复制。let-7c可下调CSFV的RNA复制水平。
The study was to construct a recombinant vector bearing the let-7c gene and to research on potential regulation of classical swine fever virus（CSFV）by let-7. let-7c was selected by Bioinformatics of RNA22. Two pairs of single DNA chain encoding pre-let-7c were synthesized, and were ligated to the expression vector pGenesil-1.1-dBm2. The recombinant plasmid pGene-pre-let-7c was constructed and transfected into the swine umbilicus vein endothelial cells(SUVEC) by liposome after extraction and purification. The positive clones were selected by G418 screening. We also analyzed the expression of CSFV through the a
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