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Background Apolygus lucorum is a worldwide omnivorous pest damaging a range of crops and causing great economic losses. Symbiotic bacteria living in insects play a key role in the nutrition, physiology, and behavior of hosts. Here, we present an experiment using Illumina HiSeq sequencing targeting the V3–V4 regions of bacteria’s 16S rRNA throughout the entire life cycle of A. lucorum. Results The first and second instar nymphs have the largest alpha diversity compared with other life stages of the insect. Bacterial phyla Proteobacteria (72.29%), Firmicutes (15.24%), Actinobacteria (7.76%) exhibit the largest relative abundance in all developmental stages. Erwinia (23.97%) and Lactococcus (10.62%) are the two genera with the highest relative abundance. The relative abundance of Erwinia in the nymph stage is significantly greater than the adult stage, and the relative abundance of Lactococcus in 6-day-old and 9-day-old adult females is higher compared with adult males. Conclusions These results reveal that microbial community composition and relative abundance shift dynamically at different life stages, implying that different bacterial phyla and genera may have specific roles in specific life stages such as metabolism, nutrition absorption, detoxification, and reproduction. This study reveals for the first time the community composition and ecological dynamics of symbiotic bacteria throughout the life stages of A. lucorum, and thus may provide insight to new strategies for pest control.

Background Aphis gossypii Glover (Hemiptera: Aphididae), a worldwide polyphagous phloem-feeding agricultural pest, has three wing morphs (winged parthenogenetic female, gynopara, and male) in the life cycle. The exclusive males could fly from summer hosts to winter hosts, which are essential for gene exchanges of cotton aphid populations from different hosts or regions. However, the molecular mechanism of wing differentiation of male in A. gossypii remains unclear. Results Morphological observation of male A. gossypii showed that there is no distinct difference in the external morphologies of the 1st and 2nd instar nymphs. The obvious differentiation of wing buds started in the 3rd instar nymph and was visible via naked eyes in the 4th instar nymphal stage, then adult male emerged with full wings. According to morphological dynamic changes, the development of wings in males were divided into four stages: preliminary stage (the 1st instar to 2nd instar), prophase (the 3rd instar), metaphase (the 4th instar), anaphase (the 5th instar). Results of feeding behavior monitoring via EPG (electrical penetration graph) technology indicated that although the male cotton aphids had strong desire to feed (longer duration of C 55.24%, F 5.05% and Pd waves 2.56%), its feeding efficiency to summer host cotton was low (shorter E1 3.56% and E2 waves 2.63%). Dynamic transcriptome analysis of male aphid at 5 different developmental periods showed that in the 3rd instar nymph, the number of up-regulated DEGs was significant increased, and time-course gene transcriptional pattern analyses results also showed that numerous genes categorized in clusters 3, 5, and 8 had the highest expressed levels, which were consistent with morphological changes of wing buds. These results indicate that the 3rd instar nymph is the critical stage of wing bud differentiation in males. Furthermore, through pathway enrichment analysis of DEGs and WGCNA, it revealed that the neuroactive ligand-receptor interaction, Ras signaling pathway, dopaminergic synapse, circadian entrainment and the corresponding hub genes of PLK1, BUB1, SMC2, TUBG, ASPM, the kinesin family members (KIF23, KIF20, KIF18-19) and the novel subfamily of serine/threonine (Aurora kinase A and Aurora kinase B) probably played an important role in the critical stage of wing bud differentiation. Conclusion This study explored morphological changes and genes transcriptional dynamics males in cotton aphid, revealed the phenomenon of low feeding efficiency of winged males on summer host cotton, and identified key signaling pathways and potential hub genes potentially involved in wing bud differentiation of male in A. gossypii.

Soybean is one main source of dietary protein; therefore, improving protein content is an important objective in breeding programs. There is a significant negative correlation between protein and oil content, which influenced mapping quantitative trait locus (QTL) and quantitative trait nucleotides for these two traits. In this study, a linkage map was created with 2232 single-nucleotide polymorphism markers for the four-way recombinant inbred line (FW-RIL) population derived from the cross (Kenfeng 14 × Kenfeng 15) × (Heinong 48 × Kenfeng 19), and then conditional and unconditional QTL analyses were carried out by inclusive complete interval mapping based on the phenotypic data of protein and oil content collected in 10 different environments. As shown in the results of linkage analysis, a total of 85 QTL have been detected. We have performed association analysis using 109,676 markers after quality filtering for FW-RIL, and the results have shown that a total of 60 QTNs were detected. We have performed association analysis using 63,306 markers after quality filtering for resource population, and the results have shown that a total of 123 QTNs were detected. We have combined linkage and association analysis, and there are six QTNs verified by FW-RIL and resource population. We have performed pathway analysis on the genes in these six QTN attenuation regions, and the result shows that a total of four candidate genes are related to the synthesis or metabolism of soybean protein. These findings will facilitate marker-assisted selection and molecular breeding of soybean.

Background Greenhouse cultivation is mainly a monoculture system, which leads to severe soil degradation, with significant changes to the structure of the soil microbial community. The present study aimed to determine the effects of fertilizer and waterlogging (WL) on the microbial community of soil that was continuously monocropped with cucumber in a greenhouse for 3 years (2016–2019). Biolog EcoPlates™ and high-throughput sequencing were used to investigate the abundance, structure, and diversity of the soil microbial community. Results Compared with the initial total soluble salt content (8.65 g/kg), total soluble salt content after WL significantly decreased to 0.597 g/kg. Compared to control (CK) soil, the abundance of fungal species in the chemical fertilizer plus waterlogging (CFWL)-treated soil increased by 40.5%, while bacterial species abundance in the organic fertilizer plus waterlogging (OFWL)-treated soil increased by 10.7%. Furthermore, the relative abundance of Arthrobacter, Geobacter, and Bacillus was higher in OFWL-treated soil than CFWL-treated soil (p Conclusions The application of CFWL to greenhouse soil under continuous monoculture produces fungal-dominated soil, whereas OFWL application alone produces bacterial-dominated soil. Graphical Abstract

Background Cotton (Gossypium spp.) is one of the most important economic crops worldwide, and its production plays an important role in the economy of many countries. Genetically modified herbicide-tolerant (GMHT) crops, which were developed to minimize the losses caused by weeds, have gradually become the most widely adopted genetically modified crops in the world due to their economic and environmental benefits. However, the potential ecological and environmental risks of GMHT crops have attracted extensive attention and controversy. Arthropod communities form a prominent part of the biodiversity of agroecosystems and are important indicators of environmental health. Elucidating the effects of GMHT crops on the diversity of arthropod communities is necessary to ensure the safety of GMHT crops. Result In this 2-year study, we investigated the potential impact of GMHT crops on arthropod communities. The GMHT cotton variety GGK2 with glyphosate tolerance and its near-isogenic non-GMHT variety K312 were used for the experimental groups. The Shannon diversity index (H), Simpson diversity index (D), Pielou evenness index (J), and principal co-ordinates analysis (PCoA) of the Bray–Curtis distance were used to evaluate the population dynamics and biodiversity of arthropods in cotton fields. No significant differences were found between GGK2 and K312 in their total abundance of arthropod communities, and biodiversity indexes on most sampling dates. The arthropod composition in the GGK2 and K312 plots was similar. Sampling dates had a significant effect on biodiversity indexes, whereas no clear tendencies related to cotton variety or cotton variety × sampling dates interaction were recorded. In addition, PCoA revealed high similarity between the arthropod communities in the plots of the GMHT cotton variety GGK2 and its near-isogenic variety K312. Conclusion There was no obvious difference in abundance, diversity indexes of arthropod communities between GMHT cotton variety GGK2 and its near-isogenic variety K312 under the small-scale planting regime.

Pod number is an important component of yield in soybean (Glycine max (L.) Merr.), and pods are unevenly distributed in the upper, middle and lower parts of the plant. Here, linkage analysis combined with genome-wide association study (GWAS) was used to identify 20 pod number-related traits in four-way recombinant inbred lines (FW-RILs) derived from crosses between the four soybean varieties (Kenfeng 14 × Kenfeng 15) × (Heinong 48 × Kenfeng 19). The results show that pod number-related traits are highly influenced by genetic factors, while the environment plays only a minor role. A total of 602 QTLs were identified, of which 52 were detected in multiple environments (over two environments). In addition, GWAS detected 26 common QTNs (identified by multiple methods or environments) in the QTL intervals. Based on gene ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, 11 potential candidate genes were identified that likely involved the growth and development of soybean pods. These findings will help elucidate the genetic basis of pod number traits.

Betulinic acid (BA), a pentacyclic triterpene of natural origin, has been demonstrated to have varied biologic activities including anti-viral, anti-inflammatory, and anti-malarial effects; it has also been found to induce apoptosis in many types of cancer. However, little is known about the effect of BA on normal cells. In this study, the effects of BA on normal neuronal cell apoptosis and the mechanisms involved were studied using differentiated PC12 cells as a model. Treatment with 50 μM BA for 24 h apparently induced PC12 cell apoptosis. In the early stage of apoptosis, the level of intracellular reactive oxygen species (ROS) increased. Afterwards, the loss of the mitochondrial membrane potential, the release of cytochrome c and the activation of caspase-3 occurred. Treatment with antioxidants could significantly reduce BA-induced PC12 cell apoptosis. In conclusion, we report for the first time that BA induced the mitochondrial apoptotic pathway in differentiated PC12 cells through ROS.

Oncolytic virotherapy is a cancer treatment in which replication-competent viruses are used that specifically infect, replicate in and lyse malignant tumour cells, while minimizing harm to normal cells. Anecdotal evidence of the effectiveness of this strategy has existed since the late nineteenth century, but advances and innovations in biotechnological methods in the 1980s and 1990s led to a renewed interest in this type of therapy. Multiple clinical trials investigating the use of agents constructed from a wide range of viruses have since been performed, and several of these enrolled patients with urological malignancies. Data from these clinical trials and from preclinical studies revealed a number of challenges to the effectiveness of oncolytic virotherapy that have prompted the development of further sophisticated strategies. Urological cancers have a range of distinctive features, such as specific genetic mutations and cell surface markers, which enable improving both effectiveness and safety of oncolytic virus treatments. The strategies employed in creating advanced oncolytic agents include alteration of the virus tropism, regulating transcription and translation of viral genes, combination with chemotherapy, radiotherapy or gene therapy, arming viruses with factors that stimulate the immune response against tumour cells and delivery technologies to ensure that the viral agent reaches its target tissue.

Two pairs of amino-acid functionalized poly(3,4-ethylenedioxythiophene) (PEDOT) derivatives, namely, poly(N-(tert-butoxycarbonyl)-L-methionyl (3,4-ethylenedioxythiophene-2’-yl)methylamide) (L-PEDOT-Boc-Met) and poly(N-(tert-butoxycarbonyl)-D-methionyl (3,4-ethylenedioxythiophene-2’-yl)methylamide) (D-PEDOT-Boc-Met); poly(L-methionyl (3,4-ethylenedioxythiophene-2’-yl)methylamide) (L-PEDOT-Met) and poly(D-methionyl (3,4-ethylenedioxythiophene-2’-yl)methylamide) (D-PEDOT-Met) were synthesized via chemical oxidative polymerization of corresponding monomers. The structural characterization, spectroscopic properties and thermal stability of these monomers and polymers were systematically explored by FTIR spectra, Raman spectra, XRD spectra, UV-Vis spectra and thermogravimetric analysis. As chiral electrode materials, these polymers were employed to successfully recognize 3,4-dihydroxyphenylalanine (DOPA) enantiomers by cyclic voltammetry (CV) in sulphuric acid solution. The measurement results reveal that the tendency was hetero-chiral interaction between L-PEDOT-Met/PVA/GCE and D-DOPA, D-PEDOT-Met/PVA/GCE and L-DOPA, respectively. Also, the mechanism of chiral discrimination was discussed. All the results implied that the combination of electrochemical molecular recognition technology and chiral PEDOT materials can be a promising approach for chiral recognition and may open new opportunities for facile, biocompatible, sensitive and robust chiral assays in biochemical applications.

In order to well understand the molecular basis of heterosis in soybean, the methylation-sensitive amplification polymorphism (MSAP) method based on capillary electrophoresis was used to estimate levels and patterns of cytosine methylation in 15-day post-emergence leaves of four parental lines [Jilin 47 (no. 19), EXP (no. 12), Jilin 38 (no. 3) and Yi 3 (no. 6)] and 12 hybrids [Jilin 38 × Yi 3(3 × 6), Jilin 38 × EXP(3 × 12), Jilin 38 × Jilin 47(3 × 19), Yi 3 × Jilin 38(6 × 3), Yi 3 × EXP(6 × 12), Yi 3 × Jilin 47(6 × 19), EXP × Jilin 38(12 × 3), EXP × Yi 3(12 × 6), EXP × Jilin 47(12 × 19), Jilin 47 × Jilin 38(19 × 3), Jilin 47 × Yi 3(19 × 6), Jilin 47 × EXP(19 × 12)]. In addition, 12 traits of the hybrids and their parents were also analyzed to understand the relationship between DNA methylation variation and heterosis. MSAP results showed that the total relative methylation level of all hybrids was lower than the corresponding middle parent value, indicating that the methylation degree was decreasing. And may express a variety of genes related to the phenotypic variation of hybridization. Moreover, the hemi-methylation levels of Jilin 38 × Jilin 47 and Yi 3 × Jilin 47 hybrids and full-methylation levels of EXP × Yi 3 and EXP × Jilin 47 hybrids was significant higher than the corresponding mid-parent values. In addition, the heredity of methylation from parents in hybrids is more than the variations, in which there were four types appeared great higher: A1, B4, B8, and D2. Furthermore, the results of relationship between genetic variation in DNA methylation and heterosis showed that the hypo-methylation had a promoting effect to increase node number, and the hype-methylation of hybrids was helpful to add to stem thick. Our results may provide new insights into well understanding the molecular mechanisms of heterosis at the epigenetic level in soybean.

We herein report the electrosynthesis of an aminomethyl functionalized poly(3,4-ethylenedioxythiophene) (PEDOT) derivative, poly(2′-aminomethyl-3,4-ethylenedioxythiophene) (PEDOT-MeNH2), in CH2Cl2-Bu4NPF6 (0.1 mol·L-1) system containing 2% boron trifluoride diethyl etherate (BFEE). The electrochemical behavior, structure characterization, thermal properties and surface morphology of this novel polymer were systematically investigated by cyclic voltammetry (CV), Fourier-transform infrared spectroscopy (FTIR), thermogravimetry (TG) and scanning electron microscopy (SEM), respectively. Electrochemistry results demonstrated that PEDOT-MeNH2 film displayed good redox properties and high electrochemical stability. Besides, PEDOT-MeNH2 films exhibited the electrochromic nature with obvious color changing from purple in the reduced form to blue upon oxidation. By further investigation, kinetic studies revealed that PEDOT-MeNH2 film had decent contrast ratio (41.8%), favorable coloration efficiency (152.1 cm2·C-1), low switching voltages and moderate response time (2.4 s). Satisfactory results implied that the obtained PEDOT-MeNH2 film is a promising optoelectronic material and holds promise for electrochromic devices and display applications.

The authors describe an electrochemical immunoassay for α-fetoprotein (α-FP) using a glassy carbon electrode (GCE) modified with a nanocomposite made from gold nanoparticles, graphene oxide and multi-walled carbon nanotubes (AuNPs/GO-MWCNTs) and acting as a signal amplification matrix. The nanocomposite was synthesized in a one-pot redox reaction between GO and HAuCl4 without using an additional reductant. The stepwise assembly of the immunoelectrode was characterized by means of cyclic voltammetry and electrochemical impedance spectroscopy. The interaction of antigen and antibody on the surface of the electrode creates a barrier for electrons and causes retarded electron transfer, this resulting in decreased signals in differential pulse voltammetry of hexacyanoferrate which is added as an electrochemical probe. Using this strategy and by working at a potential of 0.2 V (vs. SCE), a wide analytical range (0.01 - 100 ng∙mL‾1) is covered. The correlation coefficient is 0.9929, and the limit of detection is as low as 3 pg∙mL‾1 at a signal-to-noise ratio of 3. This electrochemical immunoassay combines the specificity of an immunological detection scheme with the sensitivity of an electrode modified with AuNPs and GO-MWCNTs.

Targeting HER-2 over-expressing breast cancer cells with trastuzumab has resulted in significant improvements in both disease-free and overall survival rates. However, despite a favorable initial response, some cancer cells become resistant and develop into fatal metastatic disease. Here we report that we can specifically target HER-2 over-expressing and trastuzumab-resistant breast cancer cells by using an engineered lentivirus which has trastuzumab bound to its envelope. In vitro, this lentiviral construct mediated both the expression of reporter genes, such as enhanced green fluorescent protein (EGFP) and firefly luciferase, as well as the therapeutic gene, herpes thymidine kinase (hTK), in HER-2 over-expressing cells. Subsequent application of the pro-drug ganciclovir selectively killed breast cancer cells in which lentivirus mediated expression of hTK. In vivo, we successfully targeted the expression of firefly luciferase to trastuzumab-resistant breast cancer tumors established in nude mice. Furthermore, we found that systemic administration of trastuzumab-bound lentivirus led to expression of EGFP in circulating trastuzumab-resistant breast cancer cells. In conclusion, HER-2 over-expressing breast cancer cells resistant to trastuzumab can be targeted for selective gene expression and destruction by viruses with envelope-proteins engineered to bind to this antibody.