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Global biodiversity loss has generated great interest in the role of plant communities in driving ecosystem functions. There is limited understanding of how soil properties, plant richness and plant community composition interact to affect ecosystem multifunctionality.We conducted a constructed ecosystem experiment by simultaneously manipulating soil origin (i.e. fertile farmland soil and relatively infertile bare land soil), plant richness and community composition (one‐species monoculture, and all possible two‐, three‐ and four‐species combinations of five plants) to evaluate their influence on ecosystem multifunctionality related to the accumulation of biomass, carbon (C) and nitrogen (N) in plants, greenhouse gas emissions, soil nutrients, soil N fixation and mineralization of N and phosphorus (P).We found that ecosystem multifunctionality was significantly affected by soil origin, plant community composition and the community‐weighted mean (CWM) of plant biomass, but not by plant richness.We grouped the community composition into the N‐fixing group (including N‐fixing plants) and the non‐N‐fixing group (excluding N‐fixing plants). The N‐fixing plant group exhibited significantly higher multifunctionality than the non‐N‐fixing species group in both soil origins. For bare land soil, multifunctionality increased with the increasing relative abundance and biomass ratio of Albizia julibrissin (N‐fixing species) in communities, but decreased with the biomass ratio of Platycladus orientalis (non‐N‐fixing species). For farmland soil, multifunctionality increased with the abundance of Toona sinensis (non‐N‐fixing species) and the biomass ratio of Albizia julibrissin, but decreased with the abundance and biomass ratio of Morus alba (non‐N‐fixing species). These results indicate that the key species determining ecosystem multifunctionality vary under different soil conditions.Synthesis and applications: We propose that plant community composition and the relative abundance and biomass ratio of key species drive ecosystem multifunctionality. We suggest that selecting the appropriate plant combination under different soil conditions should be emphasized in ecological restoration projects. Our study highlights the differentiated roles of key species on ecosystem functions under different resource conditions. The N fixation in general plays a crucial role in driving ecosystem multifunctionality and the N‐fixing plants can serve as restoration tools in nutrient‐poor degraded lands. [ABSTRACT FROM AUTHOR]

In the investigation of stratigraphic reservoirs, a significant discrepancy frequently exists between the delineation of the formation pinch-out line as traced using the characteristics of seismic wave reflections and the actual location of the formation pinch-out line. This has been the main problem restricting further hydrocarbon exploration and development. In this study, Hala'alate Mountain on the northwestern margin of the Junggar Basin is taken as an example for carrying out the study of stratigraphic reservoirs by integrating logging, drilling, and 3D seismic data. On the one hand, in studies based on the identification of formation pinch-out points using seismic data, the identification error of reservoir pinch-out lines is reduced by the improved included angle extrapolation method by utilizing the half energy attribute. On the other hand, the Poisson's ratio curve is reconstructed using acoustic curves and oil-gas sensitive logging, then the reservoir oil-bearing facies zone is predicted using Poisson's ratio post-stack genetic inversion to comprehensively analyze the controlling factors of stratigraphic reservoirs. The study area mainly features structural lithologic reservoirs, structural stratigraphic reservoirs and stratigraphic overlaps that pinch out reservoirs. The boundary of a stratigraphic reservoir is affected by the dip angle of the unconformity surface, the formation dip angle, and other factors. The improved included angle extrapolation method improves the identification accuracy of stratigraphic overlap pinch-out reservoirs. The reservoir distribution then is calculated according to Poisson's ratio inversion, improving the prediction accuracy for the reservoir. This method improves the predictive effect for stratigraphic reservoirs and provides a new idea for the exploration and development of similar reservoirs. [ABSTRACT FROM AUTHOR]

Transcription factor ATF1 is a member of the ATF/CREB family of the CREB subfamily and is involved in physiological processes such as tumorigenesis, organ development, reproduction, cell survival, and apoptosis in mammals. However, studies on ATF1 in fish have been relatively poorly reported, especially on its role in antiviral immunity in fish. In this study, ATF1 from orange-spotted grouper (named EcATF1) were cloned and characterized. Molecular characterization analysis showed that EcATF1 encodes a 307-amino-acid protein, containing PKID and bZIP_CREB1 domains. Homology analysis showed that had the highest homology with E. lanceolatus (88.93%). Tissue expression pattern showed that EcATF1 was extensively distributed in twelve selected tissues, with higher expression in the skin, gill, liver and spleen. Subcellular localization analysis showed that EcATF1 was distributed in the nucleus of GS cells. EcATF1 overexpression inhibits Singapore grouper iridovirus (SGIV) and red-spotted grouper nervous necrosis virus (RGNNV) replication, as evidenced by a diminished degree of CPE induced by SGIV and RGNNV and a reduction in the level of viral gene transcription and viral capsid protein expression. Furthermore, EcATF1 overexpression upregulated interferon pathway-related genes and proinflammatory factors, and increased the promoter activities of IFN, IFN stimulated response element (ISRE), and nuclear factor κB(NFκB). Meanwhile, EcATF1 overexpression positive regulate the MHC-I signaling pathway, and upregulated the promoter activity of MHC-I. Collectively, these data demonstrate that EcATF1 plays an important role during the host antiviral immune response. This study provides insights into the function of ATF1 in the immune system of lower vertebrates. • We cloned and characterized ATF1 (EcATF1) from grouper. • EcATF1 inhibit SGIV and RGNNV replication in GS cells. • EcATF1 upregulated IFN pathway and proinflammatory factors. • EcATF1 positive regulate the MHCI pathway. [ABSTRACT FROM AUTHOR]

Regulatory factor X 5 (RFX 5) is a member of the RFX family, and it forms the transcription factor complex RFX with RFXANK/B and RFXAP. The RFX complex can activate MHC expression by binding to the MHC promoter. However, the regulate mechanism of RFX in fish species is not been fully elucidated. In this study, we investigated the transcriptional regulation of Epinephelus akaara RFX5 (EaRFX5) on EaMHCI, and its effect on immune pathways. The genomic sequence of EaRFX5 was 35,774 bp and consisted of ten exons and nine introns. The length of EaRFX5 ORF sequence is 2,160 bp, encoding 719 amino acids. By qRT-PCR, EaRFX5 was detected constitutively expressed in twelve selected tissues, showing a wide range of expression. EaRFX5 expression parttern in response to poly (I:C), LPS, Zymosan A, SGIV, and NNV challenges showed that EaRFX5 plays a differentiated immunomodulatory role in response to various stimuli in different tissues, and EaRFX 5 was most significantly upregulated in the kidney after challenge with SGIV. Subcellular localization assays showed that EaRFX5 is a typical nuclear protein. Based on the in vitro overexpression experiments, EaRFX5 appeared to promote the expression of EaMHCIa gene, interferon signalling pathway and inflammatory cytokine. Luciferase reporter assay showed that the −267 bp to +82 bp region of EaMHCIa promoter was the core region where EaRFX5 modulated. Additionally, point mutations and electrophoretic mobility shift assays indicating M3 is the EaRFX5 binding sites in the EaMHCIa promoter. These results contribute to elucidating the function of EaRFX5 in fish immune response, and provide the first evidence of positive regulation of MHCIa expression by RFX5 in fish. • The molecular characteristics of EaRFX5 were analysed. • EaRFX5 positively promotes the transcription expression of many cytokines. • RFX5 activates MHC Iα expression by binding M3 site on its promoter. [ABSTRACT FROM AUTHOR]

Multivariate time series forecasting aims to predict time series data comprising several linked variables or characteristics and is frequently used in stock forecasting, energy forecasting, etc. The tough task is to acquire further historical data to forecast future values while boosting the capacity to mine relationships between and within sequences. The existing methods neglect the weighted influence of various neighbors and relationships on the sequence instance, as well as the semantic information of the instance itself, making the inter-instance correlation measure inaccurate. Meanwhile, the length of the sequence input is limited and the variable features in the multivariate sequence are treated equally, short-term and multi-feature interference cannot be eliminated, causing the learnt time series features to deviate from the real features. In this work, we provide a Multivariate Time Series Forecasting model that emphasizes Relationships between and within sequences (MTSFR). Use the BERT model to characterize the text attributes of instances and construct basic semantic embeddings. Meanwhile, instance-level and relation-level attention are used to model topological relations among different instances. Computes the cross-correlation of multivariate sequences within instances and performs attention weighting for multivariate sequence encoding. And choose the Transformer model to realize the trend prediction of long-term multivariate series. Experimental results show that the F 1 value of our approach achieves 68.50% and 74.66% under the CSI300 and S&P500 data sets respectively, both of which are superior to the SOTA technique. Furthermore, the model is suited for small-scale sequence relationship modeling and is effective at handling long-term multivariate sequence forecasting problems. [ABSTRACT FROM AUTHOR]

Background and aims: Agricultural abandonment has been taken as one of the most widely used strategies for ecological restoration. Abandoned croplands expanded worldwide since the middle of the twentieth century and will increase considerably in the future. Whether agricultural abandonment alters the abundances of soil carbon (C) and nitrogen (N) mineralization genes, and whether these functional genes are linked to alterations in C and N mineralization rates remain unknown. Methods: We took advantage of a well-established chronosequence of nature restoration sites on abandoned croplands which represent a century of vegetation succession in China's Qinling Mountains, to determine soil C and N mineralization rates, and their relationships with vegetation succession, edaphic characteristics, soil microbial communities, and functional genes based on GeoChip 5.0. Results: We found that soil C and N mineralization rates, microbial biomass and composition, and the number and abundances of functional genes were significantly affected by vegetation succession following agricultural abandonment. Soil C and N mineralization rates increased by sixfold and threefold, respectively, along the cropland to forest successional gradient. The NO3-N, NH4-N and soil available phosphorus (P) concentrations were important factors associated with the C and N mineralization genes. The shifts in edaphic environments (i.e., soil moisture, cation exchange capacity, and C/P ratio), vegetation-derived substrates (i.e., soil organic C and N), and soil microbial composition (i.e., Fungi/Bacteria ratio, amounts of Gram-negative bacteria, Actinomycetes, and arbuscular mycorrhizal fungi), rather than the abundances of functional genes involved in mineralization processes, controlled soil C and N mineralization rates along the long-term vegetation successional gradient. Conclusions: Abandoning cropland for natural succession could facilitate the recuperation of soil C and N processes and alter soil microbial composition and functional genes. The abundances of microbial functional genes are less important than previously expected in regulating soil C and N mineralization rates. [ABSTRACT FROM AUTHOR]

The alkylation of toluene catalyzed by modified HZSM-5 was an economical and efficient way to produce para-xylene (PX) due to the full utilization of toluene and fewer by-products. It has attracted significant attention in optimizing the modification method for both high activity and PX selectivity. In this study, we employed SiO2 and MgO to co-modify HZSM-5 for the alkylation of toluene with dimethyl carbonate. The catalysts in which SiO2 was deposited first with trimethoxysilane (TMOS) as the precursor, showed significantly higher activity and PX selectivity than that of depositing MgO first. When the content of SiO2 and MgO was both 5%, the conversion of toluene was 12%, with the selectivity of PX up to 85% (400 °C) for the 5Si-5Mg/ZSM-5 catalyst (depositing SiO2 first). However, the conversion and selectivity were only 5% and 56% for the 5Mg-5Si/ZSM-5 catalyst (depositing MgO first). The analysis of structure and acid properties indicated that the pre-deposition of SiO2 can regulate the location of MgO, leading to the suppression of the external acid sites and the inhibition of the pore blockage by MgO. Owing to the pore size of ZSM-5 being slightly smaller than the molecular size of TMOS, TMOS molecules would be embedded in the pore entrance, making SiO2 tend to prevent MgO from entering the micropore of ZSM-5. [ABSTRACT FROM AUTHOR]

Carbon (C) allocation plays an important role in plant adaptation to water and nutrient stresses. However, the effects of drought and nutrient deficiencies on the allocation of recently fixed C in the plant–soil–microbe system remain largely unknown. Herein, we studied the response of C allocation of Sophora moorcroftiana (an indigenous pioneer shrub in Tibet) to drought, nitrogen (N) deficiency and phosphorus (P) deficiency using a microcosm experiment. The 13CO2 continuous labeling was used to trace C allocation in the plant–soil–microbe system. We found that drought significantly reduced plant 13C, but it increased 13C accumulation in soil. The decreased plant 13C under drought was attributed to the decrease of 13C in stem and root rather than that in leaf. The excess 13C fraction in the microbial biomass (MB13C) was reduced by N deficiency, but it was not affected by the combination of drought and N deficiency, indicating that drought weakened the effects of N deficiency on MB13C. By contrast, MB13C increased under the combination of drought and P deficiency, suggesting that drought enhanced the effects of P deficiency on MB13C. Drought and nutrient deficiencies regulated the belowground 13C allocation. Specifically, drought and P deficiency increased the allocation of 13C to root and N deficiency regulated the allocation of 13C to microbial biomass C and dissolved organic C in soil. Notably, soil 13C decreased with increasing plant 13C, while MB13C first decreased and then increased with increasing plant 13C. Overall, our study demonstrated that drought and nutrient deficiencies interactively affected C allocation in a plant–soil–microbe system and provided insights into C allocation strategies in response to multiple resource (water and nutrient) stresses under environmental changes. [ABSTRACT FROM AUTHOR]

Porcine reproductive and respiratory syndrome virus (PRRSV) isolates show high genetic and pathogenic diversity. The mechanisms underlying different virulence of PRRSV isolates are still not fully clarified. Two highly homologous PRRSV isolates (XJ17-5 and JSTZ1712-12) with distinct virulence were identified in our previous study. To evaluate the association between host responses and different virulence, here we investigated the transcriptomic profiles of porcine alveolar macrophages (PAMs) infected with these two isolates. RNA-Seq results showed that there are 1932 differential expression genes (DEGs) between two PRRSV infected groups containing 1067 upregulation and 865 downregulation genes. Compared with the avirulent JSTZ1712-12 infected group, GO analysis identified significant enrichment gene sets not only associated with virus infection but also innate immune response in the virulent XJ17-5 infected group. In addition, KEGG analysis indicated significantly enriched genes associated with NOD-like and RIG-I-like receptor signaling pathways in XJ17-5 vs JSTZ1712-12 group. Furthermore, XJ17-5 isolate induced significantly higher levels of innate immune response associated genes (IL-1β, CXCL2, S100A8, OAS2, MX1, IFITM3, ISG15 and IFI6) than JSTZ1712-12 isolate, which were further confirmed by real-time PCR. Given that these two isolates share similar replication efficiency in vivo and in vitro , our results indicated that distinct virulence of PRRSV isolates is associated with different host innate immune responses. • PRRSV virulent XJ and avirulent JS isolates had similar replication efficiency in PAMs. • RNA-seq analysis identified significantly different expression genes in XJ vs JS group. • GO analysis suggested that XJ and JS infection induced different innate immune responses. • KEGG analysis identified DEGs associated with NOD-like and RIG-I-like receptor signaling pathways in XJ vs JS group. • Real-time PCR results supported that XJ and JS infection induced different innate immune responses. [ABSTRACT FROM AUTHOR]

Meta-learning has been introduced in the recommendation domain, and a possible direction to extend graph-based meta-learning is how to exploit higher-order information between nodes. The current studies primarily rely on pre-embedding methods to utilize user attributes, inadvertently overlooking the crucial co-occurrence patterns among users' features. This oversight hinders the discovery of implicit connections between users. Furthermore, in scenarios of infrequent interactions, the reliance on initial edge information constrains connections between nodes in the same category. This constraint compromises the update capability of node embeddings, leading to reduced recommendation accuracy. In this paper, a meta-learning recommendation method with a dynamic node clustering knowledge graph (DCKG) is proposed. By introducing user attribute nodes and a triple-gated attention networks, this approach facilitates connections between users based on attribute relationships and enables the balancing of information across various pathways. Additionally, the integration of a dynamic aggregation module frees nodes of the same category from initial connection constraints, fostering more direct connections and further augmenting the propagation capability of higher-order information. The experimental results show that DCKG achieves the excellent results in the cold-start recommendation. DCKG can extend the use of higher-order features in the graph by direct connection. [ABSTRACT FROM AUTHOR]

To date, four species of porcine circoviruses (PCVs), including PCV1‐4, have been reported to exist in the clinical cases. Fast and effective differential detection is critical to monitor the infection and co‐infection status of PCVs for adopting reliable control strategies. However, currently available methods cannot simultaneously differentiate the four species of PCV strains. In this study, a quadruplex real‐time PCR assay based on TaqMan probes was developed for differential detection of PCV1‐4. The new quadruplex real‐time PCR assay exhibited satisfied specificity, sensitivity, repeatability and reproducibility. In addition, the new assay was applied to the detection of 120 clinical samples collected from 2016 to 2020 in Jiangsu province of China and compared with previously reported PCV1‐4 singleplex conventional PCR assays. Based on the clinical performance, the results from the quadruplex real‐time PCR and conventional PCR assays showed 100% agreement. A total of 47 samples were detected as PCV positive by the quadruplex real‐time PCR assay, including 1, 2, 1 samples were co‐infected with PCV1 and PCV4, PCV2 and PCV3, PCV2 and PCV4, respectively. Full‐length ORF2 sequencing and phylogenetic analysis supported the real‐time PCR results that 5, 34, 8 and 4 of the 51 PCV sequences were PCV1, PCV2, PCV3 and PCV4, respectively. This study provides a promising alternative tool for rapid differential detection of PCVs and confirms the coexistence of all species of PCV1‐4 strains in Jiangsu province in recent years. [ABSTRACT FROM AUTHOR]

Multiple commercial porcine reproductive and respiratory syndrome (PRRS) modified live vaccines are currently utilized in Chinese swine herds due to the limited cross‐protection of vaccines and coexistence of different PRRS viruses. In this study, an infectious cDNA clone of the highly pathogenic PRRS (HP‐PRRS) vaccine JXA1‐R strain was generated. We successfully rescued the virus from direct in vitro DNA transfection of rJXA1‐R clone, which has similar growth kinetics to the parental JXA1‐R virus in Marc‐145 cells. To further evaluate the potential use of the cloned rJXA1‐R virus as a live vector for foreign gene expression, the enhanced green fluorescent protein (EGFP) was inserted between non‐structural and structural genes. Our results showed that the dynamic expression of EGFP can be visualized by live cell imaging system during the infection in Marc‐145 cells. The availability of our cloned JXA1‐R viruses provides a crucial platform to study the fundamental biology of HP‐PRRS virus vaccine and also serves as a potential effective vector for developing live vector vaccines against swine pathogens. [ABSTRACT FROM AUTHOR]

Public bidding for the information and communication technology (ICT) products offers an external regulatory perspective to identify endogenous risks of ICT supply chain. Owing to the multi-level outsourcing, the modeling methods of the first-order topological similarity are prone to misjudgment. Moreover, only using basic structural attributes (such as enterprise type, registered capital, etc.) is difficult to accurately quantify the enterprise' supply capacity, resulting in the models cannot identify the risky nodes with insufficient supply capacity. In this work, a risk identification Model for ICT supply chain based on Network Embedding and Text Encoding (NETEM) is proposed. In addition to the basic business features of enterprises, the DeepWalk is utilized to obtain the high-order topological representation of the ICT supply chain. Meanwhile, the TextCNN combined with keyword sequence extraction is utilized to supplement text semantic information, and excavate the association between business scope and supply capacity of enterprises. Finally, the basic business features, high-level topological features and text semantic features are spliced to obtain the final enterprise node representation vector, then the node risk classification model is trained. In addition, an ontology is developed for ICT supply chain integration and risk knowledge reuse. The experimental results show that NETEM improves the F1 value of the optimal baseline algorithm by 7.3% on the ICT risk identification data set, and the case study in financial industry demonstrates that the model can be practically applied to identify the risk of supply interruption. [ABSTRACT FROM AUTHOR]

Few-shot named entity recognition (NER) faces a challenge of obtaining more generalized class representations with limited labeled instances to recognize named entities. However, few support instances are insufficient to encompass the intra-class diverse entity semantics, and learning the similarity between query instances and support instances in isolation predisposes dispersed class distributions and fuzzy boundaries of certain classes, leading to misclassification. Meanwhile, there are differences in the meanings of the same class labels under different target domains, which leads to low accuracy of label referents generated based on label words, affecting the similarity metric between query instances and label referents. To overcome the problem, we propose a new method, J oint C ontrastive learning with semantic E nhanced L abel R eferents for few-shot NER (JCELRNER). Specifically, we propose a strategy for representing the class using multiple referents, including support instance tokens and label prototypes. A joint contrastive loss objective that simultaneously is proposed to optimize the distributional distance between query instances and all class referents in the same semantic space by jointly considering token-to-token and token-to-label correlations, promoting the intra-class compactness. Meanwhile, JCELRNER proposes a dual semantic enhancement module to generate reliable label referents that adapt to different target domains by fusing entity and context semantic information. Extensive experiments show that by promoting the intra-class relevance of referents of the same class and enhancing the label referents with dual semantic information, the model achieves a comprehensive and accurate understanding of the entire class, thereby enhancing the generalization ability to novel classes, outperforming the other competitive approach. [ABSTRACT FROM AUTHOR]

In black-box scenarios, adversarial attacks against text classification models face challenges in ensuring highly available adversarial samples, especially a high number of invalid queries under long texts. The existing methods select distractors by comparing the confidence vector differences obtained before and after deleting words, and the query increases linearly with the length of the text, making it difficult to apply to attack scenarios with limited queries. Generating adversarial samples based on a thesaurus can lead to semantic inconsistencies and even grammatical errors, making it easy for the target model to recognize adversarial samples and resulting in a low success rate of attacks. A parallel and highly stealthy A dversarial A ttack against T ext C lassification M odel (AdATCM) is proposed, which reinforces dual-task of attack and generation. This method does not require querying the target model during the selection of distractors. Instead, it directly uses contextual information to calculate the importance of words and selects distractors in one go, strengthening the concealment of attacks. Integrating KL divergence loss, cross entropy loss, and adversarial loss to construct an objective function for training an adversarial sample attack model, generating adversarial samples that can fit the original sample distribution and strengthen the success rate of attacks. The experimental results show that this method has a high success rate and strong concealment, effectively reducing the number of attack queries under long text conditions. [ABSTRACT FROM AUTHOR]

Magnetic carbon-based composites derived from metal-organic frameworks have been regarded as potential microwave absorption (MA) materials. Here, we successfully fabricate magnetic CoFe alloy@nitrogen-doped carbon shell (CoFe@NC) composites with strong absorption, thin thickness, and wide bandwidth through the thermal decomposition of CoFe Prussian blue analogues. Annealing temperature has a remarkable influence on dielectric and magnetic behavior of composites, thereby improving the impedance matching and MA ability. When the annealing temperature of CoFe@NC composites is 600 ℃, the CoFe@NC composites show the best MA performance with the reflection loss (RL) value of − 50.77 dB and the maximum effective absorbing bandwidth (RL ≤ −10 dB) of 7.2 GHz (2.1 mm). The CoFe@NC composites possess superior MA properties because of the high dielectric loss deriving from nitrogen-doped carbon as the shell, high magnetic loss originating from CoFe alloy as the core and conduction loss. The superior MA performance of CoFe alloy@NC composites make them ideal candidates for high-efficient MA applications. • CoFe Prussian blue analogue is an ideal template for microwave absorption. • Nitrogen-doped carbon shell (NC) provides more dipole polarization. • CoFe@NC have properties of strong absorption, thin thickness and wide bandwidth. • The preparation method of CoFe@NC is very simple. [ABSTRACT FROM AUTHOR]

Mammalian studies have shown that the nuclear transcription factor Y (NFYC) regulates the expression of major histocompatibility complex (MHC) by binding to CCAAT-box on promoters. However, few studies have focused on the regulatory mechanisms of NFYC in MHC pathway in fish. To explore the transcriptional regulatory mechanism of MHCIa in fish, we characterized NFYC and MHCIa of red-spotted grouper (Epinephelus akaara) (named EaNFYC and EaMHCIa, respectively). The EaNFYC genome sequence is 13,796 bp and contains 1,065 bp open reading frame. It is composed of ten exons and nine introns and encode a 354 amino acid sequence. The putative EaNFYC protein sequence shared 67.2–99.4% identity to vertebrate NFYC and possesses a typically conserved domain (histone- or haem-associated protein 5 domain (HAP5)) at the N-terminus. Transcripts of both EaNFYC and EaMHCIa were ubiquitously expressed in all detect tissues, and higher mRNA levels were detected in immune-relevant tissues (middle-kidney). EaNFYC expression increased after treatment with polyinosinic: polycytidylic acid, lipopolysaccharide, nervous necrosis virus, zymosan A, and Singapore grouper iridovirus. Analysis of subcellular localization indicated that EaNFYC was localized at the cell nucleus only. Furthermore, overexpression of EaNFYC significantly stimulated the expression of EaMHCIa , interferon signalling molecules and inflammatory cytokine. The region −878 bp to +82 bp of EaMHCIa promoter was identified to be the core promoter which EaNFYC take effect on. Additionally, point mutations and electrophoretic mobility shift assays verified that NFYC activate MHCIa expression by binding at the M1 and M2 binding sites that do not contain CCAAT-box. These results contribute to elucidating the function of fish NFYC on MHC transcriptional mechanisms, and provide the first evidence of positive regulation of MHCIa expression by NFYC in fish. • NFYC and MHCIa of E. akaara are functionally characterized. • Expression of these two genes is the highest in kidney. • NFYC activate MHCIa expression by binding with no CCAAT-box on its promoter. [ABSTRACT FROM AUTHOR]

The classical major histocompatibility complex class I (MHC-Ⅰ) molecule plays a key role in vertebrate immune response for its important functions in antigen presentation and immune regulation. MHC pathway is closely related to many diseases involving autoimmunity, antigen intrusion and inflammation. However, rare literatures about the effect of MHC-I on fish cells apoptosis were reported. In this study, a novel type of MHC-Ⅰα genotype from orange-spotted grouper (named EcMHC-ⅠA*01) were cloned and characterized. It shared a 77% identity to its Epinephelus coioides MHC-Iα homology that has been uploaded to NCBI (ACZ97571.1). Molecular characterization analysis showed that EcMHC-ⅠA*01 encodes a 357-amino-acid protein, containing a signal peptide，α1，α2，α3, Cytoplasmic (Cyt) and Transmembrane (TM) domains. Tissue expression pattern showed that EcMHC-ⅠA*01 was extensively distributed in twelve selected tissues, with higher expression in the gill, intestine and skin. The expression of EcMHC-ⅠA*01 in grouper liver and spleen tissues were significantly induced by different stimuli (Zymosan A, LPS, Ploy I:C, RGNNV and SGIV). Comparing with the EcMHC-ⅠA*01 expression levels induced by Zymosan A, Ploy I:C and RGNNV, the effects induced by SGIV and LPS were more significant. Subcellular localization analysis showed that EcMHC-ⅠA*01 localizes throughout the cytoplasm appeared both diffuse and focal intracellular expression pattern. Overexpression of EcMHC-ⅠA*01 inhibited the CPE progression, the mRNA expression of the SGIV related genes (MCP, LITAF, ICP-18 and VP19) and the protein expression of MCP. Meanwhile, qRT-PCR result showed that EcMHC-ⅠA*01 overexpression upregulated the expression of interferon signaling molecules (IFN-γ, ISG56, MDA5 and MXI) and inflammatory cytokines (IL-1β, IL-6, TNF-α and TRAF6). In addition, our results showed that overexpression of EcMHC-ⅠA*01 promoted the apoptosis of normal fathead minnow (FHM) cells as well as the apoptosis of FHM cells induced by SGIV. However, there was no significant change in the activity of caspase 3 between control group and EcMHC-ⅠA*01 overexpression group, suggesting that EcMHC-ⅠA*01-induced apoptosis may not depend on the caspase 3 pathway. Taken together, these data in our study provide new insights into the role of MHC-I in antiviral immune response and apoptosis in fish. • We cloned and characterized a novel type of MHC-Ⅰα (EcMHC-ⅠA*01) from Epinephelus coioides. • EcMHC-ⅠA*01 inhibits the replication of SGIV in vitro. • Overexpression of EcMHC-ⅠA*01 promoted the apoptosis of FHM cells. • These data provide a valuable reference for studies on MHC expression regulation mechanism in fish. [ABSTRACT FROM AUTHOR]

Porcine epidemic diarrhea virus (PEDV) frequently causes diarrhea outbreaks. However, whether newly discovered enteric viruses such as porcine kobuvirus (PKV) and porcine astroviruses (PAstVs) are also correlated with diarrhea is still unclear. Diarrhea outbreaks were reported in a PEDV-vaccinated pig farm in Xinjiang Uygur Autonomous Region of China from 2019 to 2020. PEDV was a common pathogen detected in fecal samples by routine RT-PCR assays. The PEDV positive fecal sample was used for pathogenic analysis due to the failure isolation of PEDV. The challenged neonatal piglets appeared watery diarrhea within one day post infection (dpi) and all died within 6 dpi. Histopathological and immunohistochemical examinations supported that PEDV is a major pathogen causing intestinal lesions. To further explore enteric viruses associated with neonatal piglet diarrhea, metagenomics sequencing was performed for the diarrheic piglets. Remarkably, PKV was the most abundant virus (58.33%) followed by PEDV (34.45%) and PAstVs (7.22%), which were also confirmed by real-time RT-PCR assays. Significant in vivo replications of PEDV and PKV could only be observed in challenged piglets whilst PAstVs maintained similar virus loads in both challenged and mock infected piglets. Overall, this study provides first pathogenic and metagenomic evidence that significant proliferations of PEDV and PKV are closely associated with severe diarrhea in neonatal piglets, while PAstVs likely play limited roles in neonatal piglet diarrhea. • Pathogenic analysis suggested that PEDV is likely associated with 2019–2020 Xinjiang diarrhea outbreaks. • Metagenomics sequencing identified PEDV, PKV and PAstVs from severe diarrheic piglets. • Significant in vivo replications of PEDV and PKV were only detected in diarrheic neonatal piglets. • PAstVs maintained similar virus loads in both challenged and mock infected piglets during the animal study. • PEDV and PKV are closely associated with diarrheic diseases while PAstVs may play a limited role in neonatal piglet diarrhea. [ABSTRACT FROM AUTHOR]

• Two chimeric PRRSV strains containing consensus sequences of ORF2-4 or ORF5-6 genes were generated. • These chimeric viruses had distinct in vitro and in vivo replication efficacy. • Pig inoculation of both chimeric viruses did not cause obvious clinical signs. • Both chimeric viruses could induce heterologous nAbs but only confer partial cross protection. • Minor and major envelope proteins probably have synergistic effects on inducing heterologous nAbs and conferring cross protection. High genetic diversity of porcine reproductive and respiratory syndrome virus (PRRSV) isolates is a major obstacle for the development of effective PRRS vaccines. A chimeric highly pathogenic PRRSV2 (HP-PRRSV2) strain containing the consensus sequence of ORF2-6 genes was constructed in our previous study, which could induce broadly neutralizing antibodies (bnAbs) and confer satisfied cross protection against virulent NADC30-like isolate. To further elucidate the roles of minor and major envelope proteins encoded by ORF2-4 and ORF5-6 genes in conferring cross protection, two chimeric HP-PRRSV2 strains (rJS-ORF2-4-CON and rJS-ORF5-6-CON) containing consensus sequences of ORF2-4 or ORF5-6 were constructed and rescued in this study. The rJS-ORF5-6-CON strain has similar replication efficiency as the backbone HP-PRRSV2 rJSTZ1712-12 virus, while rJS-ORF2-4-CON has significantly lower in vitro and in vivo replication efficiency comparing to rJS-ORF5-6-CON. Animal inoculation indicated that both rJS-ORF2-4-CON and rJS-ORF5-6-CON did not cause obvious clinical signs in piglets and could induce heterologous nAbs after immunization. Challenge with a virulent heterologous NADC30-like SD17-38 isolate showed that even though both immunized groups presented lower viremia, faster virus elimination, less fever and alleviated lung gross lesions when compared with the only challenged pigs, rJS-ORF2-4-CON and rJS-ORF5-6-CON could not confer enough cross protection. Considering the bnAbs and satisfied cross protection induced by the chimeric virus containing ORF2-6 consensus sequence, our results support that minor and major envelope proteins play synergistic roles in inducing broader nAbs and conferring better cross protection. [ABSTRACT FROM AUTHOR]

Porcine reproductive and respiratory syndrome virus (PRRSV) causes huge economic loss to the global swine industry. Even though several control strategies have been applied, PRRS is still not effectively controlled due to the continuous emergence of new variants and limited cross-protection by current vaccines. During the routine epidemiological investigation in 2017, two PRRSV variants were identified from a severe abortion farm and a clinically healthy farm, respectively. The viruses were isolated and denominated as XJ17-5 and JSTZ1712-12. Genomic sequencing indicated that their genomes are both 14,960 bp in length sharing 99.45% nucleotide identity. Sequence alignments identified a discontinuous 30-amino-acid deletion and a continuous 120-amino-acid deletion in nsp2 of both isolates. Genome-based phylogenetic analysis confirmed that XJ17-5 and JSTZ1712-12 belong to the HP-PRRSV subtype but form a new branch with other isolates containing the same 150-amino-acid deletion in nsp2. Pathogenic analysis showed that XJ17-5 is highly virulent causing 60% mortality, while JSTZ1712-12 is avirulent for piglets. Furthermore, fragment comparisons identified 34-amino-acid differences between XJ17-5 and JSTZ1712-12 that might be associated with the distinct virulence. The identification of highly homologous HP-PRRSV variants with new genetic feature and distinct virulence contributes to further analyze the pathogenesis and evolution of PRRSV in the field. [ABSTRACT FROM AUTHOR]