Integrated mendelian randomization analyses highlight AFF3 as a novel eQTL-mediated susceptibility gene in renal cancer and its potential mechanisms.

BACKGROUNDS: A growing number of expression quantitative trait loci (eQTLs) have been found to be linked with tumorigenesis. In this article, we employed integrated Mendelian randomization (MR) analyses to identify novel susceptibility genes in renal cancer (RC) and reveal their potential mechanisms. METHODS: Two-sample MR analyses were performed to infer causal relationships between eQTLs, metabolites, and RC risks through the "TwoSampleMR" R package. Sensitivity analyses, such as heterogeneity, pleiotropy, and leave-one-out analysis, were used to assess the stability of our outcomes. Summary-data-based MR (SMR) analyses were used to verify the causal relationships among cis-eQTLs and RC risks via the SMR 1.3.1 software. RESULTS: Our results provided the first evidence for AFF3 eQTL elevating RC risks, suggesting its oncogenic roles (IVW method; odds ratio (OR) = 1.0005; 95% confidence interval (CI) = 1.0001-1.0010; P = 0.0285; heterogeneity = 0.9588; pleiotropy = 0.8397). Further SMR analysis validated the causal relationships among AFF3 cis-eQTLs and RC risks (P < 0.05). Moreover, the TCGA-KIRC, the ICGC-RC, and the GSE159115 datasets verified that the AFF3 gene was more highly expressed in RC tumors than normal control via scRNA-sequencing and bulk RNA-sequencing (P < 0.05). Gene set enrichment analysis (GSEA) analysis identified six potential biological pathways of AFF3 involved in RC. As for the potential mechanism of AFF3 in RC, we concluded in this article that AFF3 eQTL could negatively modulate the levels of the X-11,315 metabolite (IVW method; OR = 0.9127; 95% CI = 0.8530-0.9765; P = 0.0081; heterogeneity = 0.4150; pleiotropy = 0.8852), exhibiting preventive effects against RC risks (IVW method; OR = 0.9987; 95% CI = 0.9975-0.9999; P = 0.0380; heterogeneity = 0.5362; pleiotropy = 0.9808). CONCLUSIONS: We concluded that AFF3 could serve as a novel eQTL-mediated susceptibility gene in RC and reveal its potential mechanism of elevating RC risks via negatively regulating the X-11,315 metabolite levels.

Investigating the spatiotemporal expression of CBTS genes lead to the discovery of tobacco root as a cembranoid-producing organ.

Tobacco cembranoids, known for their anti-insect and antifungal properties, were shown to be mainly present on the surface of leaves and flowers, being biosynthesized by their trichomes. It remains unclear whether they could be biosynthesized in other organs without trichomes. Cembratrien-ol synthases (CBTSs) catalyze the conversion of GGPP to CBT-ols and thus play an important role in cembranoid biosynthesis. This study identified the CBTS family genes in tobacco and examined their spatiotemporal expression patterns. The CBTS genes showed diverse expression patterns in tobacco organs, with the majority highly expressed in leaves and a few highly expressed in flowers. The expression of CBTS genes were also correlated with the development of tobacco plants, and most of them showed the highest expression level at the budding stage. Furthermore, their expression is mediated by the JA (jasmonate) signaling in all tobacco organs. Several CBTS genes were found to be highly expressed in tobacco roots that have no trichomes, which prompted us to determine the cembranoid production in roots and other organs. GC-MS and UPLC assays revealed that cembranoids were produced in all tobacco organs, which was supported by the bioactivity assay results that almost all these CBTS enzymes could catalyze CBT-ol biosyntheis in yeast, and that the content ratio of CBT-ols and CBT-diols in tobacco roots was different to that in leaves. This work sheds insights into the expression profiles of tobacco CBTS genes and provides a feasibility to engineer tobacco roots for industrial production of cembranoids.

Interaction of Glycemic Control and Statin Use on Diabetes-Tuberculosis Treatment Outcome: A Nested Case-Control Study.

This study aims to explore the interaction of glycemic control and statin use on the treatment outcomes of pulmonary tuberculosis-diabetes comorbidity (PTB-DM) patients. A nested case-control study was conducted in a tuberculosis patients' cohort. We defined cases as patients who experienced unfavorable outcomes. Glycemic control was estimated at the baseline. Statin use was obtained from medical records. The multivariate logistic regression models were developed, and the interaction table invented by Andersson was adopted to analyze the interaction of glycemic control and statin use on treatment outcomes. A total of 2,047 patients were included in this study. There was a significant interaction between glycemic control and statin use on the treatment outcomes. Patients with good glycemic control and no statin use (OR = 0.464, 95% CI: 0.360-0.623) had a lower risk of unfavorable outcomes than those with poor glycemic control and statin use (OR = 0.604, 95% CI: 0.401-0.734). Patients with good glycemic control and statin use had the lowest risk of unfavorable outcomes (OR = 0.394, 95% CI: 0.264-0.521). Glycemic control in diabetes-tuberculosis treatment should be paid considerable attention. Patients can benefit from statin use even if they have poor glycemic control. Patients with good glycemic control and statin use can have the best outcomes.

A tonoplast-localized TPK-type K+ transporter (TPKa) regulates potassium accumulation in tobacco.

Potassium ion (K+) is one of the most essential nutrients for the growth and development of tobacco (Nicotiana tabacum L.), however, the molecular regulation of K+ concentration in tobacco remains unclear. In this study, a two-pore K (TPK) channel gene NtTPKa was cloned from tobacco, and NtTPKa protein contains the unique K+ selection motif GYGD and its transmembrane region primarily locates in the tonoplast membrane. The expression of NtTPKa gene was significantly increased under low-potassium stress conditions. The concentrations of K+ in tobacco were significantly increased in the NtTPKa RNA interference lines and CRISPR/Cas9 knockout mutants. In addition, the transport of K+ by NtTPKa was validated using patch clamp technique, and the results showed that NtTPKa channel protein exclusively transported K+ in a concentration-dependent manner. Together, our results strongly suggested that NtTPKa is a key gene in maintaining K+ homeostasis in tobacco, and it could provide a new genetic resource for increasing the concentration of K+ in tobacco.

Loop PDE of viral capsid protein is involved in immune escape of the emerging novel variant infectious bursal disease virus.

Infectious bursa disease (IBD) is an acute, highly contactable, lethal, immunosuppressive infectious disease caused by the Infectious bursa disease virus (IBDV). Currently, the emerged novel variant IBDV (nVarIBDV) and the sustainedly prevalent very virulent IBDV (vvIBDV) are the two most prevalent strains of IBDV in China. The antigenic properties of the two prevalent strains differed significantly, which led to the escape of nVarIBDV from the immune protection provided by the existing vvIBDV vaccine. However, the molecular basis of the nVarIBDV immune escape remains unclear. In this study, we demonstrated, for the first time, that residues 252, 254, and 256 in the PDE of VP2 are involved in the immune escape of the emerging nVarIBDV. Firstly, the IFA-mediated antigen-antibody affinity assay showed that PBC and PDE of VP2 could affect the affinity of vvIBDV antiserum to VP2, of which PDE was more significant. The key amino acids of PDE influencing the antigen-antibody affinity were also identified, with G254N being the most significant, followed by V252I and I256V. Then the mutated virus with point or combined mutations was rescued by reverse genetics. it was further demonstrated that mutations of V252I, G254N, and I256V in PDE could individually or collaboratively reduce antigen-antibody affinity and interfere with antiserum neutralization, with G254N being the most significant. This study revealed the reasons for the widespread prevalence of nVarIBDV in immunized chicken flocks and provided innovative ideas for designing novel vaccines that match the antigen of the epidemic strain.

OASL suppresses infectious bursal disease virus replication by targeting VP2 for degrading through the autophagy pathway.

Infectious bursal disease (IBD) is an acute and fatal immunosuppressive disease caused by infectious bursal disease virus (IBDV). As an obligate intracellular parasite, IBDV infection is strictly regulated by host factors. Knowledge on the antiviral activity and possible mechanism of host factors might provide the theoretical basis for the prevention and control of IBD. In this study, RNA-sequencing results indicated that many host factors were induced by IBDV infection, among which the expression levels of OASL (2´,5´-oligadenylate synthetase-like protein) was significantly upregulated. OASL overexpression significantly inhibited IBDV replication, whereas OASL knockdown promoted IBDV replication. Interestingly, the antiviral ability of OASL was independent of its canonical enzymatic activity, i.e., OASL targeted viral protein VP2 for degradation, depending on the autophagy receptor p62/SQSTM1 in the autophagy pathway. Additionally, the 316 lysine (K) of VP2 was the key site for autophagy degradation, and its replacement with arginine disrupted VP2 degradation induced by OASL and enhanced IBDV replication. Importantly, our results for the first time indicate a unique and potent defense mechanism of OASL against double-stranded RNA virus by interaction with viral proteins, which leads to their degradation. IMPORTANCE: OASL (2´,5´-oligadenylate synthetase-like protein) exhibits broad-spectrum antiviral effects against single-stranded RNA viruses in mammals, potentially serving as a promising target for novel antiviral strategies. However, its role in inhibiting the replication of double-stranded RNA viruses (dsRNA viruses), such as infectious bursal disease virus (IBDV), in avian species remains unclear. Our findings indicated a unique and potent defense mechanism of OASL against dsRNA viruses. It has been previously shown in mammals that OASL inhibits virus replication through increasing interferon production. The groundbreaking aspect of our study is the finding that OASL has the ability to interact with IBDV viral protein VP2 and target it for degradation and thus exerts its antiviral effect. Our results reveal the interaction between avian natural antiviral immune response and IBDV infection. Our study not only enhances our understanding of bird defenses against viral infections but can also inform strategies for poultry disease management.

Molecular Structure Engineering of Isomeric Additives for Long Lifetime Zn Anodes.

Modulating the solvation structure of hydrated zinc ions using organic additives stands as a pragmatic approach to suppress dendrite formation and corrosion on zinc metal anodes (ZMAs), thereby enhancing the rechargeability of aqueous Zn-ion batteries. However, fundamental screening principles for organic additives with diverse molecular structures remain elusive, especially for isomers with the same molecular formula. This study delves into the impact of three isomeric hexagonal alcohols (mannitol, sorbitol, and galactitol) as additives in adjusting Zn2+ solvation structural behaviors within ZnSO4 baseline electrolytes. Electrical measurements and molecular simulations reveal the specific molecular structure of mannitol, which features interweaving electron clouds between adjacent hydroxyl groups, achieving a high local electron cloud density. This phenomenon significantly enhances desolvation abilities, thus establishing a more stable anode/electrolyte interface chemistry. Even at 5 mA cm-2 for 2.5 mAh cm-2 capacity, Zn||Zn symmetric cells with mannitol-regulated electrolyte display an impressive 1170 h lifespan, far exceeding those with other isomer additives and is nearly tenfold longer than that with a pure ZnSO4 electrolyte (120 h). Rather than strictly adhering to focusing on chemical composition, this study with emphasis on optimizing molecular structure offers a promising untapped dimension to screen more efficient additives to enhance the reversibility of ZMAs.

N123I mutation in the ALV-J receptor-binding domain region enhances viral replication ability by increasing the binding affinity with chNHE1.

The subgroup J avian leukosis virus (ALV-J), a retrovirus, uses its gp85 protein to bind to the receptor, the chicken sodium hydrogen exchanger isoform 1 (chNHE1), facilitating viral invasion. ALV-J is the main epidemic subgroup and shows noteworthy mutations within the receptor-binding domain (RBD) region of gp85, especially in ALV-J layer strains in China. However, the implications of these mutations on viral replication and transmission remain elusive. In this study, the ALV-J layer strain JL08CH3-1 exhibited a more robust replication ability than the prototype strain HPRS103, which is related to variations in the gp85 protein. Notably, the gp85 of JL08CH3-1 demonstrated a heightened binding capacity to chNHE1 compared to HPRS103-gp85 binding. Furthermore, we showed that the specific N123I mutation within gp85 contributed to the enhanced binding capacity of the gp85 protein to chNHE1. Structural analysis indicated that the N123I mutation primarily enhanced the stability of gp85, expanded the interaction interface, and increased the number of hydrogen bonds at the interaction interface to increase the binding capacity between gp85 and chNHE1. We found that the N123I mutation not only improved the viral replication ability of ALV-J but also promoted viral shedding in vivo. These comprehensive data underscore the notion that the N123I mutation increases receptor binding and intensifies viral replication.

Infectious bursal disease virus VP5 triggers host shutoff in a transcription-dependent manner.

Viruses have evolved intricate mechanisms to evade host antiviral responses and exploit cellular resources by manipulating the expression profile of host genes. During infection, viruses encode proteins with shutoff activity to globally inhibit host protein synthesis, which is an effective strategy for immune evasion. In this study, compelling evidence shows that infectious bursal disease virus (IBDV) infection triggers the suppression of host protein synthesis. Furthermore, using both in vitro and in vivo viral infection models, we have identified that IBDV specifically impedes the transcription of host genes via the shutoff activity of viral VP5, simultaneously conferring advantages to IBDV infection in these circumstances. The proposed mechanism suggests that VP5 competitively binds to RanBP1, disrupting the RanGDP/GTP gradient. This disruption interferes with cellular nucleocytoplasmic transport, impairing the nuclear import of proteins bearing nuclear localization signals. The nuclear transport of pivotal transcriptional regulatory factors, such as p65 and IFN regulatory factor 7, is also compromised, leading to the inhibition of pro-inflammatory cytokines and interferon expression. This newly discovered strategy employed by IBDV enables them to manipulate host gene expression, providing novel insights into how viruses evade host immune responses and establish infections.IMPORTANCEViruses manipulate host processes at various levels to regulate or evade both innate and adaptive immune responses, promoting self-survival and efficient transmission. The "host shutoff," a global suppression of host gene expression mediated by various viruses, is considered a critical mechanism for evading immunity. In this study, we have validated the presence of host shutoff during infectious bursal disease virus (IBDV) infection and additionally uncovered that the viral protein VP5 plays a pivotal role in inhibiting the overall synthesis of host proteins, including cytokines, through a transcription-dependent pathway. VP5 competitively binds with RanBP1, leading to disruption of the Ran protein cycle and consequently interfering with nucleocytoplasmic transport, which ultimately results in the suppression of host gene transcription. These findings unveil a novel strategy employed by IBDV to evade host innate immunity and rapidly establish infection. This study also suggests a novel supplement to understanding the pathway through which viruses inhibit host protein synthesis.

Barriers and facilitators of implementing electronic monitors to improve adherence and health outcomes in tuberculosis patients: protocol for a systematic review based on the Consolidated Framework for Implementation Research.

BACKGROUND: Tuberculosis (TB) has been regarded as 'a relentless scourge', increasing morbidity and mortality and burdening vulnerable populations. Poor adherence to TB treatment and ineffective traditional interventions hinders TB control. A novel TB approach called 'electronic monitors', equipping medication boxes with daily audio or visual reminders for electronically monitoring medication intake, seems promising in improving adherence and health outcomes and overcoming the weaknesses of traditional interventions. However, no review has systematically examined and synthesized the influencing factors of implementing electronic monitors. Implementation research offers the means to analyse the influencing factors of the implementation and its process, fitting well with the aim of this review. Therefore, the widely recognized Consolidated Framework for Implementation Research (CFIR), which offers a common taxonomy for evaluating intervention implementation, will be adopted to systematically identify barriers and facilitators of the electronic monitors for improving adherence and health outcomes in patients with TB. METHODS AND ANALYSIS: The systematic review will follow the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Literature research will be conducted in five electronic databases (Ovid MEDLINE, CINAHL, EMBASE, Cochrane Library and Web of Science) to identify the barriers and facilitators of implementing electronic monitors in patients with TB. The CFIR will be used as a guide for categorizing and synthesizing the barriers and facilitators. Study screening, data extraction, quality appraisal and data analysis will be conducted by two independent reviewers. The use of additional reviewers will solve any disagreements between the two reviewers. DISCUSSION: Given the increased prominence of TB epidemiology and the adherence problem of electronic monitors, there is a solid rationale for synthesizing the existing studies via the CFIR. The findings and conclusion of this review will lay bare the achievements and effectiveness of implementing electronic monitors, as well as the attendant gaps and limitations. Further strategies for facilitating the implementation of electronic monitors will also be explored. This review will be of essential significance for research and practice, supporting future academic research initiatives centred on patients with TB and aiding electronic monitor design in lowering the morbidity and mortality associated with TB disease. TRIAL REGISTRATION NUMBER: PROSPERO: CRD42023395747.

Enterococcus faecium C171: Modulating the Immune Response to Acute Lethal Viral Challenge.

Commensal bacteria modulate acute immune responses to infection in hosts. In this study, Enterococcus faecium C171 was screened and isolated. This strain has similar basic characteristics to the reference probiotic, including strong anti-inflammatory and anti-infective effects. E. faecium C171 inhibits the production of pro-Caspase-1 and significantly reduces the production of interleukin-1ß (IL-1ß) in vitro. These reactions were confirmed using the Transwell system. Live E. faecium C171 mainly exerted an inhibitory effect on acute inflammation, whereas the anti-infective and immune-activating effects were primarily mediated by the E. faecium C171-produced bacterial extracellular vesicles (Efm-C171-BEVs). Furthermore, in the specific pathogen-free (SPF) chicken model, oral administration of E. faecium C171 increased the relative abundance of beneficial microbiota (Enterococcus and Lactobacillus), particularly Enterococcus, the most important functional bacteria of the gut microbiota. E. faecium C171 significantly inhibited the acute inflammatory response induced by a highly virulent infectious disease, and reduced mortality in SPF chickens by 75%. In addition, E. faecium C171 induced high levels of CD3+, CD4-, and CD8- immunoregulatory cells and CD8+ killer T cells, and significantly improved the proliferative activity of T cells in peripheral blood mononuclear cells, and the secretion of interferon-γ. These findings indicate that E. faecium C171 and Efm-C171-BEVs are promising candidates for adjuvant treatment of acute inflammatory diseases and acute viral infections.

A Novel Variant of Avian Reovirus Is Pathogenic to Vaccinated Chickens.

Avian reovirus (ARV) infections, characterized by severe arthritis, tenosynovitis, pericarditis, and poor weight gain, have become increasingly serious in recent years. The economic impact is significant as it causes growth inhibition and immunosuppression. Some commercial poultry in China have been widely vaccinated with available ARV vaccines; however, infections continue to occur even after vaccination. This study aimed to isolate a novel variant, ARV-SD19/11103, from the joint tissues of infected broiler chickens vaccinated with ARV vaccines in Shandong Province. Genetic evolution analysis of the major protective antigen σC gene in ARVs showed that ARV-SD19/11103 was located in the genotype cluster I but not in the same sub-cluster as the S1133 vaccine strain. The amino acid sequence similarity between SD19/11103 and vaccine strains S1133, 1733, and 2408 was <80%. After analyzing the amino acid sequences of the σC protein, 33 amino acid differences were found between the new variant isolate and the vaccine strains. This novel variant showed obvious pathogenicity in specific pathogen-free chicken embryos and chicks and could cause serious disease in chickens vaccinated with commercially available ARV vaccines. Cross-neutralization experiments further demonstrated a significant antigenic difference between the novel variant and genotype cluster I ARV strains. The novel variant strain isolated in this study provides an important theoretical basis for understanding the prevalence and genetic evolutionary characteristics of ARV variant strains in our country. This study identified the causes of ARVs circulating and emphasizes the needs for developing new vaccines against novel ARV variants.

Ethylene inhibits ABA-induced stomatal closure via regulating NtMYB184-mediated flavonol biosynthesis in tobacco.

Stomatal movement can be regulated by ABA signaling through synthesis of reactive oxygen species (ROS) in guard cells. By contrast, ethylene triggers the biosynthesis of antioxidant flavonols to suppress ROS accumulation and prevent ABA-induced stomatal closure; however, the underlying mechanism remains largely unknown. In this study, we isolated and characterized the tobacco (Nicotiana tabacum) R2R3-MYB transcription factor NtMYB184, which belongs to the flavonol-specific SG7 subgroup. RNAi suppression and CRISPR/Cas9 mutation (myb184) of NtMYB184 in tobacco caused down-regulation of flavonol biosynthetic genes and decreased the concentration of flavonols in the leaves. Yeast one-hybrid assays, transactivation assays, EMSAs, and ChIP-qPCR demonstrated that NtMYB184 specifically binds to the promoters of flavonol biosynthetic genes via MYBPLANT motifs. NtMYB184 regulated flavonol biosynthesis in guard cells to modulate ROS homeostasis and stomatal aperture. ABA-induced ROS production was accompanied by the suppression of NtMYB184 and flavonol biosynthesis, which may accelerate ABA-induced stomatal closure. Furthermore, ethylene stimulated NtMYB184 expression and flavonol biosynthesis to suppress ROS accumulation and curb ABA-induced stomatal closure. In myb184, however, neither the flavonol and ROS concentrations nor the stomatal aperture varied between the ABA and ABA+ethylene treatments, indicating that NtMYB184 was indispensable for the antagonism between ethylene and ABA via regulating flavonol and ROS concentrations in the guard cells.

Spatio-temporal comprehensive measurement of China's agricultural green development level and associated influencing factors.

Green development is an inevitable trend in the modernization of agriculture and rural areas, and promoting the green development of agriculture has always been an important measure for China's sustainable growth. However, due to the influence of diverse regional environments and the wide range of landscapes in China, a largely agricultural country, China is facing ongoing challenges in improving the overall level of agricultural green development and narrowing regional differences, which has recently garnered worldwide attention. This study aims to measure and analyze the agricultural green development level of 30 provinces in China (Tibet, Hong Kong, Macao, and Taiwan are not included in the target areas of this research due to a lack of data). Here, we applied GIS technology, an entropy-TOPSIS (technique for order of preference by similarity to ideal solution) model, quantitative analysis methods such as global spatial autocorrelation analysis, coldspot and hotspot analysis, and a spatial Durbin model to construct measurement models and index systems, after which we performed a comprehensive spatiotemporal analysis of China's agricultural green development level. Furthermore, the present study also analyzed the factors that influence agricultural green development in China. The present study demonstrated that: (i) between 2005 and 2020, China's overall level of agricultural green development exhibited a fluctuating upward trend, with significant improvement and enhancement in most provinces. However, the overall level of China's agricultural green development remains low, and differences at the provincial level are particularly prominent, with the main regions displaying the following descending development pattern: Eastern > Central > Western regions. (ii) The level of China's agricultural green development shows clear signs of spatial aggregation, characterized by spatial dependence and heterogeneity. Although this phenomenon is gradually weakening over time, the high levels of agricultural green development in the eastern regions and low levels in the western regions are likely to persist in the near future. (iii) Green agricultural structure, technology supply, agricultural mechanization level, and arable land area are the key factors influencing China's level of agricultural green development. Among these factors, technology supply, agricultural mechanization level, and arable land area have the largest direct impact, whereas green agricultural structure has a positive spatial spillover effect on the level of agricultural green development. Technology supply has both a positive direct impact and a negative indirect impact on the level of agricultural green development. Therefore, further improving technology supply and agricultural mechanization level can directly promote China's agricultural green development.

Arsenic Contents, Speciation and Toxicity in Germinated Rice Alleviated by Selenium.

Rice can accumulate more organic and inorganic arsenic (iAs) than other crop plants. In this study, the localization of As in rice grains was investigated using High Performance Liquid Chromatography-Inductively Coupled Plasma Mass Spectrometry (HPLC-ICP-MS) based on 26 rice varieties collected from two provinces. In all the samples, the total As contents in polished rice were 0.03-0.37 mg/kg, with average values of 0.28 and 0.21 mg/kg for two sample sets. The results of the determination of arsenic speciation in different components of rice grain showed that in the polished and brown rice the mean value of arsenite (As(III)) was nearly twice than that of arsenate (As(V)). The regional difference was observed in both total As contents and As speciation. The reason may be that As(III) is more mobile than As(V) in a dissociated form and because of soil properties, rice varieties, and the growing environment. The proportion of iAs and the total As in rice bran was higher than that in polished rice, and this is because As tends accumulate between the husk and the endosperm. In our study, selenium could alleviate the risk of arsenic toxicity at the primary stage of rice growth. Co-exposure to As and Se in germinated rice indicated that the reduction in As accumulation in polished rice reached 73.8%, 76.8%, and 78.3% for total As, As(III), and As(V) when compared with rice treated with As alone. The addition of Se (0.3 mg/kg) along with As significantly reduced the As amount in different parts of germinated rice. Our results indicated that Se biofortification could alleviate the As accumulation and toxicity in rice crops.

Comparative Pathogenicity of Three Strains of Infectious Bursal Disease Virus Closely Related to Poultry Industry.

Infectious bursal disease (IBD) is an acute, highly contagious, immunosuppressive, and fatal infectious disease of young chickens caused by infectious bursal disease virus (IBDV). Since 2017, a new trend has been discovered in the IBDV epidemic, with very virulent IBDV (vvIBDV) and novel variant IBDV (nVarIBDV) becoming the two current dominant strains in East Asia including China. In this study, we compared the biological characteristics of the vvIBDV (HLJ0504 strain), nVarIBDV (SHG19 strain), and attenuated IBDV (attIBDV, Gt strain) using specific-pathogen-free (SPF) chicken infection model. The results showed that vvIBDV distributed in multiple tissues, replicated the fastest in lymphoid organs such as bursa of Fabricius, induced significant viremia and virus excretion, and is the most pathogenic virus with a mortality of more than 80%. The nVarIBDV had a weaker replication capability and did not kill the chickens but caused severe damage to the central immune organ bursa of Fabricius and B lymphocytes and induced significant viremia and virus excretion. The attIBDV strain was found not to be pathogenic. Further studies preliminarily suggested that the expression level of inflammatory factors triggered by HLJ0504 was the highest, followed by the SHG19 group. This study is the first to systematically compare the pathogenic characteristics of three IBDVs closely related to poultry industry from the perspectives of clinical signs, micro-pathology, virus replication, and distribution. It is of great importance to obtain an extensive knowledge of epidemiology, pathogenicity, and comprehensive prevention, and control of various IBDV strains.

Differences in Pathogenicity and Vaccine Resistance Discovered between Two Epidemic Strains of Marek's Disease Virus in China.

Despite highly effective vaccines, Marek's disease (MD) causes great economic loss to the poultry industry annually, largely due to the continuous emergence of new MD virus (MDV) strains. To explore the pathogenic characteristics of newly emerged MDV strains, we selected two strains (AH/1807 and DH/18) with clinically different pathotypes. We studied each strain's infection process and pathogenicity and observed differences in immunosuppression and vaccine resistance. Specific pathogen-free chickens, unvaccinated or vaccinated with CVI988, were challenged with AH/1807 or DH/18. Both infections induced MD damage; however, differences were observed in terms of mortality (AH/1807: 77.8%, DH/18: 50%) and tumor rates (AH/1807: 50%, DH/18: 33.3%). The immune protection indices of the vaccine also differed (AH/1807: 94.1, DH/18: 61.1). Additionally, while both strains caused interferon-ß and interferon-γ expression to decline, DH/18 infection caused stronger immunosuppression than AH/1807. This inhibition persisted even after vaccination, leading to increased replication of DH/18 that ultimately broke through vaccine immune protection. These results indicate that both strains have different characteristics, and that strains such as DH/18, which cause weaker pathogenic damage but can break through vaccine immune protection, require further attention. Our findings increase the understanding of the differences between epidemic strains and factors underlying MD vaccination failure in China.

Integrative analysis of sensory evaluation and non-targeted metabolomics to unravel tobacco leaf metabolites associated with sensory quality of heated tobacco.

Introduction: Heated tobacco (Nicotiana tabacum L.) products are heating tobacco plug at a temperature of 350°C and produce different emissions in aerosol and sensory perceptions of tobacco leaf compared with combustible tobacco. Previous study assessed different tobacco varieties in heated tobacco for sensory quality and analyzed the links between sensory scores of the final products and certain chemical classes in tobacco leaf. However, contribution of individual metabolites to sensory quality of heated tobacco remains largely open for investigation. Methods: In present study, five tobacco varieties were evaluated as heated tobacco for sensory quality by an expert panel and the volatile and non-volatile metabolites were analyzed by non-targeted metabolomics profiling. Results: The five tobacco varieties had distinct sensory qualities and can be classified into higher and lower sensory rating classes. Principle component analysis and hierarchical cluster analysis showed that leaf volatile and non-volatile metabolome annotated were grouped and clustered by sensory ratings of heated tobacco. Orthogonal projections to latent structures discriminant analysis followed by variable importance in projection and fold-change analysis revealed 13 volatiles and 345 non-volatiles able to discriminate the tobacco varieties with higher and lower sensory ratings. Some compounds such as ß-damascenone, scopoletin, chlorogenic acids, neochlorogenic acids, and flavonol glycosyl derivatives had strong contribution to the prediction of sensory quality of heated tobacco. Several lyso-phosphatidylcholine and lyso-phosphatidylethanolamine lipid species, and reducing and non-reducing sugar molecules were also positively related to sensory quality. Discussion: Taken together, these discriminating volatile and non-volatile metabolites support the role of leaf metabolites in affecting the sensory quality of heated tobacco and provide new information on the types of leaf metabolites that can be used to predict applicability of tobacco varieties for heated tobacco products.

Residues E53, L55, H59, and G70 of the cellular receptor protein Tva mediate cell binding and entry of the novel subgroup K avian leukosis virus.

Subgroup K avian leukosis virus (ALV-K) is a novel subgroup of ALV isolated from Chinese native chickens. As for a retrovirus, the interaction between its envelope protein and cellular receptor is a crucial step in ALV-K infection. Tva, a protein previously determined to be associated with vitamin B12/cobalamin uptake, has been identified as the receptor of ALV-K. However, the molecular mechanism underlying the interaction between Tva and the envelope protein of ALV-K remains unclear. In this study, we identified the C-terminal loop of the LDL-A module of Tva as the minimal functional domain that directly interacts with gp85, the surface component of the ALV-K envelope protein. Further point-mutation analysis revealed that E53, L55, H59, and G70, which are exposed on the surface of Tva and are spatially adjacent, are key residues for the binding of Tva and gp85 and facilitate the entry of ALV-K. Homology modeling analysis indicated that the substitution of these four residues did not significantly impact the Tva structure but impaired the interaction between Tva and gp85 of ALV-K. Importantly, the gene-edited DF-1 cell line with precisely substituted E53, L55, H59, and G70 was completely resistant to ALV-K infection and did not affect vitamin B12/cobalamin uptake. Collectively, these findings not only contribute to a better understanding of the mechanism of ALV-K entry into host cells but also provide an ideal gene-editing target for antiviral study.