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To mitigate the impacts of land degradation and achieve sustainable development, several large-scale conservation programs including the Key Shelterbelt Construction Program, Natural Forest Conservation Program, and the Grain to Green Program have been formulated into action in China since the late 1970s and 1998, respectively [1]. However, a study based on an ESM indicated that in North and Southeast China, the increased precipitation from vegetation greening, although statistically insignificant, may cancel out enhanced evapotranspiration, resulting in weak impact on soil moisture [5]. However, in areas such as south of the Loess Plateau and South China with less moisture flux convergence to balance the increased evapotranspiration, the soil moisture at the root zone reduced by 0.01-0.03 (Fig. 2 June-July-August difference between the impact run and the control run in: (a) surface temperature (°C), (b) precipitation (mm/d), (c) evapotranspiration (mm/d), (d) integrated moisture flux convergence (mm/d) and (e) wind vector at 700 hPa (m/s). [Extracted from the article]

• Crop greening slightly decreased regional soil moisture but showed spatial variations. • Landscape pattern can affect how rainfall and soil moisture responds to crop greening. • Background precipitation increase masked the moisture deficit caused by crop greening. The discrepancy between water resource availability and agricultural production has become a dominant constraint on the sustainable development of agriculture. Recent satellite records have documented increasing vegetation growth since the 21st century, and this so-called "vegetation greening" has been unprecedented in the agricultural region of Northeast China. However, the influence of increased crop growth on regional water resources through the alteration of hydrological cycling remains unclear. This study investigated the impact of crop greening on the regional water balance in Northeast China using time-series satellite and observational records, machine learning, and numerical scenario simulations from WRF. Our results indicate that the enhanced water cycling during 2001–2020 in this region was characterized by a significant increasing trend in evapotranspiration, precipitation, and soil moisture. We found a complex sensitivity to the leaf area index (LAI) across Northeast China, with positive sensitivity in the southwestern regions and negative sensitivity in the typical black soil zones. The downwind precipitation induced by crop greening suggests that at the regional scale, the landscape pattern may play a more significant role in determining the water cycling response to crop greening. Our data-driven and model-driven results indicate that the background precipitation increase was the dominant contributor to the soil moisture increase, which masked the water deficit caused by crop greening. We also found that the continuous precipitation increasing trend projected by CMIP6 could further relieve conflicts between agriculture and water resources. In summary, our study provides insights into the impact of crop greening on the regional water balance in Northeast China and highlights the importance of considering both landscape patterns and background precipitation changes in understanding the water cycling response to crop greening. [ABSTRACT FROM AUTHOR]

Understanding the interactions between temperature regimes and vegetation cover is one of the key scientific topics in global environmental change and land surface process research. Recently, the prominent global greening trend has inspired considerable interest in examining climate feedbacks to vegetation changes. However, the impacts of recent widespread vegetation cover changes on soil temperature have been less documented and have received insufficient attention. Here, a high-resolution regional climate model was used to examine the potential impact of vegetation cover changes over the past 37 years, obtained as satellite observational data, on regional air and soil temperatures across the Heilong-Amur River Basin. Our sensitivity experiments indicated that the 1.85% increase in the regional fractional vegetation cover (FVC) from 1982 to 2018 cooled the air temperature by 0.045 °C and the soil temperature by 0.19 °C and that this cooling effect would continue in the near future, from 2016 to 2053. We found that soil temperatures were more sensitive to vegetation cover changes than air temperatures, particularly in mid-high latitude forests; this finding helps to explain the nonsignificant decrease in soil temperatures in forests over the past 40 years detected in the ERA5-Land reanalysis. Our results also suggest that vegetation restoration in forest ecosystems could mitigate the effects of climate change on permafrost environments by increasing the number of soil freezing days. • Vegetation restoration cools both air and soil temperature. • Soil temperature was more sensitive to changes in vegetation cover than air temperature. • Vegetation restoration is beneficial to stabilizing permafrost environments. [ABSTRACT FROM AUTHOR]

• Crop greening can slow climate warming, mainly in daytime. • Crop greening accelerated the asymmetric diurnal temperature cycle changes in Northeast China. • Different biophysical mechanism was found in explaining the day and night temperature changes induced by crop greening. Mid-high latitude Northeast China witnessed significant crop greening from 2001 to 2020, as evidenced by satellite records and field observations. The land surface temperature of croplands during the growing season showed a decreasing trend, suggesting negative surface temperature feedback to crop greening of agricultural ecosystems in mid-high latitude Northeast China. Using time-series remote sensing products and long-term scenario simulations, the present study highlights that crop greening can slow climate warming. Our study noted a stronger surface cooling effect induced by crop greening during the growing season in the day than at the night, which contributed to asymmetric diurnal temperature cycle changes in Northeast China. In addition, our biophysical mechanism analysis revealed aerodynamic and surface resistances as the major driving factors for the daytime land surface temperature (LST) cooling effect induced by crop greening, while the ground heat flux and ambient temperature feedback as the major attributes of the nighttime LST cooling impact due to crop greening. [ABSTRACT FROM AUTHOR]

[Display omitted] • The WRF coupled crop model was firstly calibrated and evaluated in Northeast China. • The localized crop model has robust performance in simulating crop dynamics. • The localized crop model has superiority in simulating crop activities and biomass. Northeast China is an important commodity grain base in China and plays an important role in maintaining national and local food security. The intensifying climate variability and strengthening of extreme weather events threaten crop growth and yields in this region. The dynamic crop model coupled into the land surface models showed advances in simulating crop phenology and crop growth response to climate change, however, which was mainly validated for the United States. By comparing with the satellite observed crop growth cycles, we firstly calibrated the parameters for the Weather Research and Forecasting (WRF) coupled Noah-MP-Crop model. Then, we evaluated the performance of the calibrated WRF-Noah-MP-Crop model with the default crop models and the dynamic vegetation models coupled with WRF by comparing our simulations with corresponding satellite measurements and meteorological observations. Our results indicated the augmentation of the Noah-MP-Crop model in WRF significantly improved the crop phenology simulation at the beginning and ending time of the growing season compared with the dynamic vegetation model using unmanaged crops. The satellite-calibrated crop parameters substantially improved the simulation of crop growth, plant physiology, and biomass accumulation for both corn and soybean. Coupling the localized dynamic crop model into the WRF led to considerable decreases in the simulated mean-absolute-errors (MAEs) and biases of the leaf area index, evapotranspiration, and gross primary production compared with the MODIS observed values. Compared with the statistical yield from each province, the modified crop model underestimated the corn yield from 11.1% to 48.6%, whereas overestimated the soybean yield from 16.5% to 162.6%. The coupled WRF-Noah-MP-Crop model with flexible resolutions holds unmatched advantages in estimating and projecting crop growth and yield under future climate change scenarios, which would be critical in ensuring sustainable agricultural development and maintaining future food security. [ABSTRACT FROM AUTHOR]

• Widespread greening cools surface and increases rainfall in summer over China. • Climatic responses to the greening showed significant regional variability. • Vegetation greening would decrease the risk of extreme climate events. Changes in land-use management and natural climate variability has led to significant vegetation greening in China over the past decades, as evidenced by satellite observations. In this study, we used a high-resolution land-atmosphere coupled regional climate model to assess the impacts of recent greening on China's regional summer climate. Our results inferred a country-averged surface cooling of 0.11 °C and a precipitation increase of 0.02 mm/d during summer in response to China's widespread greening. We also identified significant regional variability in the climatic responses to vegetation change. The regions of northern China showed significant cooling, including the Northeast China Plain, Loess Plateau, and the eastern areas of the Northern arid and semi-arid region; however, no significant temperature changes were simulated in southern China. Summer precipitation decreased in southern China and increased in the Huang-Huai-Hai Plain and the northern Loess Plateau. Variations in moisture flux convergence had a stronger influence on the precipitation patterns relative to evapotranspiration. Furthermore, our results suggested that vegetation greening would influence the occurrence of extreme climate events by decreasing the number of heatwave days (by 1–3 days, particularly in northern China), reducing the number of continuous drought events in northern China, and minimizing the risks of floods in southern China. [ABSTRACT FROM AUTHOR]

Porcine reproductive and respiratory syndrome (PRRS) is one of the major drivers of economic loss in the swine industry worldwide. In commercial pig production, vaccination is the first option in an attempt to control infectious diseases. Pigs are therefore often immunized with different vaccines, and almost all of them are delivered via the intramuscular (IM) route. However, the IM injection may result in physical damage, stress reactions, and is labor demanding. An alternative route is urgently needed to reduce the disadvantages of conventional vaccination. In this study, a needle-free intradermal (ID) delivery system was evaluated for delivering a live PRRS vaccine as compared with the traditional needle-syringe method. Fifty-two 4-week-old piglets were divided into six groups: piglets in groups A-C were immunized using ID delivery system with 104, 105 and 106 TCID 50 of PRRS candidate vaccine strain rHN-NP49, respectively; piglets in group D were immunized IM with 105 TCID 50 of rHN-NP49; and group E and F were used as challenge and control groups, respectively. At 28 days post vaccination, piglets in group A to E were challenged with a lethal dose of highly-pathogenic PRRSV. Similar results were found in viremia and antibody response among the ID and IM groups during the immunization stage. After challenge, similar results were found in average body weight gain, viral shedding, serum viral load, and clinical score among the immunization groups, with a higher protection ratio in the ID group compared with IM group with the same immunization dose. These results demonstrated that the ID delivery system could provide similar or even better protection compared with IM route, and could be an effective route for PRRS vaccination. [ABSTRACT FROM AUTHOR]

Feline coronavirus (FCoV) is an unsegmented, single-stranded RNA virus belonging to the Alphacoronavirus genus. It can cause fatal feline infectious peritonitis (FIP) in cats of any ages. Currently, there are no effective prevention and control measures to against FCoV. In this study, we developed a recombinant adenovirus vaccine, AD5-N, based on the nucleocapsid(N) protein of FCoV. The immunogenicity of AD5-N was evaluated through intramuscular immunization in 6-week-old Balb/c mice and 9–12 months old cats. Compared to the control group, AD5-N specifically induced a significant increase in IgG and SIgA levels in the vaccinated mice. Furthermore, AD5-N not only effectively promoted strong cellular immune responses in cats but also induced high levels of specific SIgA, effectively helping cats resist FCoV infection. Our findings suggest that adenovirus vector vaccines based on the N gene have the potential to become candidate vaccines for the prevention and control of FCoV infection. • A recombinant adenovirus vaccine candidate named AD5-N for cats was developed. • AD5-N specifically induced a significant increase in IgG and SIgA levels in the vaccinated mice and cats. • AD5-N could provide effective protection for cats resisting type I FCoV and type II FCoV infection. [ABSTRACT FROM AUTHOR]

MiR-7-5p has been demonstrated to inhibit tumorigenesis by limiting tumor cell proliferation, migration and invasion. However, its role in countering hydroquinone (HQ)-induced malignant phenotype of TK6 cells has remained unclear. The present study aimed to investigate whether miR-7-5p overexpression could restrain the malignant phenotype in TK6 cells exposed to HQ. The results displayed that HQ suppressed the expression of miR-7-5p and promoted cell cycle progression. Further investigations confirmed that miR-7-5p could decelerate the cell cycle progression by targeting Rb after acute HQ exposure. Through the regulation of the Rb/E2F1 signaling pathway, the overexpression of miR-7-5p mitigated HQ-induced malignant phenotype in TK6 cells by impeding cell cycle progression. In conclusion, miR-7-5p overexpression appears to be involved in HQ-induced malignant transformation by suppressing Rb/E2F1 signaling pathway, resulting in a deceleration of the cell cycle progression. [ABSTRACT FROM AUTHOR]

• rPRRSV-E2 immunized piglets developed high levels of antibodies against HP-PRRSV and CSFV. • Immunized pigs were well protected from the challenge of HP-PRRSV or CSFV at 20 weeks and 24 weeks post vaccination. • The immune duration of rPRRSV-E2 is at least 5 months against both HP-PRRSV and CSFV. Classical swine fever virus (CSFV) and Porcine reproductive and respiratory syndrome virus (PRRSV) are both important pathogens which seriously harm the economic swine industry worldwide. We have previously demonstrated that rPRRSV-E2 is a promising live, virus-vectored vaccine that provides 100% protection against highly pathogenic PRRSV (HP-PRRSV) and CSFV. Here, we evaluated the duration of immunity (DOI) of the vaccine strain, rPRRSV-E2. Vaccine or cell culture medium was administered to piglets at 4 weeks of age. All immunized piglets developed high levels of antibodies, which could maintain for up to 23 weeks, against PRRSV and CSFV. All immunized pigs were well protected from the challenge of HP-PRRSV or CSFV at 20 weeks and 24 weeks post vaccination. The vaccine protection rate was still 100% at 24 weeks after immunization. The immune efficacy results showed that the immune duration of rPRRSV-E2 could be up to 5 months. [ABSTRACT FROM AUTHOR]

• Gal-1 overexpression strongly inhibits PRRSV replication in multiple strains. • Gal-1 knockdown or knockout facilitates PRRSV replication. • Interaction between Gal-1 and Nsp11 might regulate IFN and ISG activation. • Gal-1 exhibits antiviral activity against EAV, PEDV, JEV, PRV, and CSFV. • Gal-1 is potentially efficacious for applications to control PRRSV infection. Porcine reproductive and respiratory syndrome virus (PRRSV) causes great economic losses to the swine industry globally; however, effective control measures for this virus are limited. Here, we screened a porcine alveolar macrophage (PAM) cDNA library with a yeast two-hybrid system to reveal that galectin-1 (Gal-1), an endogenous innate immune protein encoded by LGALS1 , interacts with nonstructural protein 11 (Nsp11) of PRRSV. Western blotting and viral titer assays indicated that Gal-1 overexpression suppressed replication in multiple PRRSV strains (P < 0.001), whereas Gal-1 knockdown or knockout increased viral titer and nucleocapsid protein expression. The Gal-1-specific anti-PRRSV effect was associated with the endoribonuclease domain of Nsp11 through inactivation of interferon-antagonist function and stimulation of interferon-stimulated gene expression. Additionally, Gal-1 interacted with PRRSV E protein but not with PRRSV glycoproteins, and recombinant Gal-1 treatment inhibited PRRSV in PAMs and MARC-145 cells. Furthermore, Gal-1 inhibited replication in multiple viruses, including equine arteritis virus, porcine epidemic diarrhea virus, pseudorabies virus, Japanese encephalitis virus, and classical swine fever virus, suggesting its potential broad application for antiviral strategies. Our findings provide insight into the important role of Gal-1 in PRRSV pathogenesis and its potential use as a novel therapeutic target against PRRSV infection. [ABSTRACT FROM AUTHOR]

Abstract In recent years, the outbreaks of porcine epidemic diarrhea (PED) caused by the highly virulent porcine epidemic diarrhea virus (PEDV) variants occurred frequently in China, resulting in severe economic impacts to the pork industry. In this study, we selected and analyzed the genetic evolution of 15 PEDV representative strains that were identified in fecal samples of diarrheic piglets in 10 provinces and cities during 2011–2017. The phylogenetic analysis indicated that all the 15 PEDV isolates clustered into G2 genotype associated with the current circulating strains. Compared with the genome of the prototype strain CV777, these strains had 103–120 amino acid mutations in their S proteins, most of which were in the N terminal domain of S1 (S1-NTD). We also found 37 common mutations in all these 15 strains, although these strains shared 96.9–99.7% nucleotide homology and 96.3–99.8% amino acid homology in the S protein compared with the other original pandemic strains. Computational analysis showed that these mutations may lead to remarkable changes in the conformational structure and asparagine (N)-linked glycosylation sites of S1-NTD, which may be associated with the altered pathogenicity of these variant PEDV strains. We evaluated the pathogenicity of the PEDV strain FJzz1 in piglets through oral and intramuscular infection routes. Compared with oral infection, intramuscular infection could also cause typical clinical signs but with a slightly delayed onset, confirming that the variant PEDV isolate FJzz1 was highly pathogenic to suckling piglets. In conclusion, we analyzed the genetic variation and pathogenicity of the emerging PEDV isolates of China, indicating that G2 variant PEDV strains as the main prevalent strains that may mutate continually. This study shows the necessity of monitoring the molecular epidemiology and the etiological characteristics of the epidemic PEDV isolates, which may help better control the PED outbreaks. Highlights • G2 variant PEDV strains as the main prevalent strains continue to mutate along with time. • The isolated strains were prone to mutate in the S protein with many common amino acid mutations. • These mutations may lead to remarkable changes in the conformational structure of S1-NTD and the pathogenicity of PEDV. • Both oral and intramuscular routes caused typical clinical signs to piglets. [ABSTRACT FROM AUTHOR]

Understanding future climate change is crucial for securing and managing water supplies necessary for agricultural activities in China, particularly in rainfed agriculture regions. This paper evaluates the projected climate change for nine major agricultural zones in China, using ensembles of regional climate models (RCMs) simulated under the Coordinated Regional Downscaling Experiment-East Asia second phase (CORDEX-EA-II) framework. The simulations were conducted for two climate scenarios (RCP2.6 and RCP8.5) at a 25 km grid spacing, with three RCMs (RegCM4, REMO, and WRF) driven by multiple CMIP5 global climate models (GCMs). The study compares the RCM simulations to the driving CMIP5 and the recent CMIP6 ensembles, focusing on surface temperature, precipitation, and surface relative humidity for the present day (1981–2010), mid-future (2036–2065), and far future (2070–2099) periods. The model evaluations indicate that the GCM and RCM simulations are consistent with observations, with RCMs showing better performance than the driving GCMs. The results show that both GCMs and RCMs project increased temperature and precipitation in most agricultural zones of China in the future, with the CMIP6 ensembles projecting the largest temperature increase and the CORDEX-EA-II ensemble showing the finest spatial details. Relative humidity is projected to decrease over major rice-producing areas of South China in the CORDEX-EA-II, CMIP5, and CMIP6 ensembles. This study provides valuable information to support climate change adaptation and mitigation efforts in China, particularly in the agricultural sectors. • CORDEX-EA-II simulations demonstrate better model performance over China. • Temperature and precipitation are projected to increase in the future. • Relative humidity is projected to decrease over South China. [ABSTRACT FROM AUTHOR]

Porcine reproductive and respiratory syndrome (PRRS) and classical swine fever (CSF) are economically significant diseases that affect the swine industry worldwide. However, the current vaccination strategy, which uses two single live attenuated vaccines, can result in interference for each other. In addition, the universally used CSFV vaccine C-strain does not allow for differentiation of infected and vaccinated animals. In this study, rPRRSV-E2, PRRS virus (PRRSV) expressing CSF virus (CSFV) E2, was constructed by reverse genetics. The E2 gene of CSFV was inserted between ORF1b and ORF2 in the genome of the PRRS vaccine virus, HuN4-F112. A copy of transcriptional regulatory sequence 6 was inserted at the 3′ terminal of the exogenous gene to produce CSFV E2 as a unique subgenomic mRNA transcript. The rPRRSV-E2 was stable for at least 25 serial cell passages. Single-shot intramuscular immunization of rPRRSV-E2 into pigs induced PRRSV-specific and CSFV-specific antibodies and fully protected pigs from lethal challenge with highly-pathogenic PRRSV and CSFV. These results demonstrate that a novel strategy for recombinant PRRSV production is effective, and suggest that rPRRSV-E2 is a promising live, virus-vectored vaccine against PRRS and a marker vaccine against CSF. [ABSTRACT FROM AUTHOR]

The marshes have undergone dramatic loss in the Sanjiang Plain since the 1950s. This paper analyzed the spatiotemporal changes of the marshes using the transition probabilities index, loss rate, and landscape indices. We also used a trajectory analysis method to trace every location of marshes over multiple points in time and to quantitatively estimate the impact of human activities on the marsh changes since the 1950s. This study indicates that the marsh area declined sharply by 79.4% (approximately 2.99 million ha) from 1954 to 2015. A large area of marsh was reclaimed as cultivated land from 1954 to 2015. The changes in the related landscape indices showed the large-scale loss of the marsh area and marsh fragmentation in the study period. Human activities were the dominant factor (87.86%) that influenced the marsh changes in the Sanjiang Plain during the last 60 years compared with natural factors. These findings can provide valuable information for better understanding wetlands changes and implementing sustainable management strategies for wetlands (such as wetland restoration). [ABSTRACT FROM AUTHOR]

KLF16, a member of KLFs (Krüppel-like factors), contributes to the progression of a variety of cancer types. There is, however, still uncertain regarding the role of KLF16 in viral replication and the signaling mechanism of type I IFN. It was discovered that KLF16 inhibited the replication of porcine epidemic diarrhea virus (PEDV) through the type I IFN signaling pathway. Besides, it can also be found that the expression of KLF16 was down-regulated after PEDV infection of LLC-PK1 cells. Furthermore, overexpression of KLF16 inhibited the replication of PEDV in Vero cells as well as LLC-PK1 cells, whereas the replication of PEDV was promoted by the knockdown of KLF16. KLF16 up-regulated the expression of interferons (IFNs) via the TRAF6-pTBK1-pIRF3 pathway with the aim of promoting the host antiviral innate immune response. In addition, the obtained findings proved that KLF16 plays a novel role in antiviral action, thereby offering novel possibilities for preventing and controlling PEDV. • KLF16 was downregulated in porcine epidemic diarrhea virus (PEDV)-infected LLC-PK1 cells. • KLF16 overexpression inhibited PEDV proliferation in both Vero cells and LLC-PK1 cells. • KLF16 silencing promoted PEDV replication. • KLF16 inhibited PEDV replication by activating type-I IFN signaling via the TRAF6-pTBK1-pIRF3 pathway. [ABSTRACT FROM AUTHOR]

Autophagy-related 4B (ATG4B) is found to exert a vital function in viral replication, although the mechanism through which ATG4B activates type-I IFN signaling to hinder viral replication remains to be explained, so far. The current work revealed that ATG4B was downregulated in porcine epidemic diarrhea virus (PEDV)-infected LLC-PK1 cells. In addition, ATG4B overexpression inhibited PEDV replication in both Vero cells and LLC-PK1 cells. On the contrary, ATG4B knockdown facilitated PEDV replication. Moreover, ATG4B was observed to hinder PEDV replication by activating type-I IFN signaling. Further detailed analysis revealed that the ATG4B protein targeted and upregulated the TRAF3 protein to induce IFN expression via the TRAF3-pTBK1-pIRF3 pathway. The above data revealed a novel mechanism underlying the ATG4B-mediated viral restriction, thereby providing novel possibilities for preventing and controlling PEDV. • ATG4B was downregulated in porcine epidemic diarrhea virus (PEDV)-infected LLC-PK1 cells. • ATG4B overexpression inhibited PEDV proliferation in both Vero cells and LLC-PK1 cells. • ATG4B knockdown promoted PEDV replication. • ATG4B hindered PEDV replication by activating type-I IFN signaling via the TRAF3-pTBK1-pIRF3 pathway. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) play important roles in viral infections, especially by modulating the expression of cellular factors essential to viral replication or the host innate immune response to infection. To identify host miRNAs important to controlling porcine reproductive and respiratory syndrome virus (PRRSV) infection, we screened 15 miRNAs that were previously implicated in innate immunity or antiviral functions. Over-expression of the miR-26 family strongly inhibited PRRSV replication in vitro, as shown by virus titer assays, Western blotting, and qRT-PCR assays. MiR-26a inhibited the replication of both type 1 and type 2 PRRSV strains. Mutating the seed region of miR-26 restored viral titers. Luciferase reporters showed that miR-26a does not target the PRRSV genome directly but instead affects the expression of type I interferon and the IFN-stimulated genes MX1 and ISG15 during PRRSV infection. These results demonstrate the important role of miR-26a in modulating PRRSV infection and also support the possibility of using host miR-26a to achieve RNAi-mediated antiviral therapeutic strategies. [ABSTRACT FROM AUTHOR]

• rPRRSV-E2 is a marker vaccine for CSFV. • rPRRSV-E2 is promising as a virus-vectored vaccine against both HP-PRRSV and CSFV infection in swine herds by single vaccination. • Maternal derived antibodies (MDAs) do not interfere with the immune efficacy of rPRRSV-E2. Currently live attenuated porcine reproductive and respiratory syndrome (PRRS) and classical swine fever (CSF) vaccines are widely used in Chinese swine herds. However, the mutual effects of vaccination procedures and severe stress caused by successive vaccinations harm piglets and make it difficult to stimulate robust and effective immune responses. In our previous study, a recombinant PRRS virus (PRRSV) vectored vaccine candidate rPRRSV-E2, which expresses CSF virus (CSFV) E2 protein, has been demonstrated being able to protect piglets against lethal challenge of highly-pathogenic (HP)-PRRSV and CSFV. In this study, we determine whether preexisting maternally derived antibodies (MDA) interfere with the immune efficacy of rPRRSV-E2. 8 experimental groups of piglets, with or without PRRSV MDAs or CSFV MDAs were immunized with a single dose of 105 TCID 50 rPRRSV-E2 or DMEM and challenged with HP-PRRSV or CSFV. Clinical characteristics, PRRSV- or CSFV-specific antibodies, viremia and pathological changes were monitored, examined and analyzed. The results showed that rPRRSV-E2-vaccinated piglets, either with or without MDAs directed against PRRSV or CSFV were completely protected from the lethal challenge of HP-PRRSV or CSFV. These results demonstrate that the MDAs do not interfere with the immune efficacy of rPRRSV-E2, which indicates that rPRRSV-E2 could have great significance in the effective prevention and control of HP-PRRSV and CSFV. [ABSTRACT FROM AUTHOR]

• RNF114 exhibits significant anti-PRRSV activity. • RNF114 knockdown facilitates PRRSV replication. • PRRSV infection leads to endogenous RNF114 upregulation. • The E3 ligase RNF114 interacts with Nsp12 and promotes its proteasomal degradation. • RNF114 catalyzes K27-linked polyubiquitination of PRRSV Nsp12. Porcine reproductive and respiratory syndrome virus (PRRSV) poses a significant threat to the swine industry worldwide, and the development of effective and sustainable measures to control PRRSV transmission remains a pressing problem. The function of PRRSV nonstructural protein 12 (Nsp12), which might play essential roles in viral replication and production, remains unknown. In this study, we identified a new host-restricted factor, porcine RING finger protein 114 (RNF114), as an inhibitor of PRRSV replication through its degradation of viral Nsp12. Western blot, quantitative real-time polymerase chain reaction, and viral titer assays indicated that RNF114 overexpression suppressed PRRSV replication, whereas RNF114 knockdown increased viral titer and nucleocapsid protein levels. Additionally, we observed that PPRSV infection led to increased RNF114 levels during the middle and late phases of infection in both porcine alveolar macrophages and MARC-145 cells. Moreover, screening of PRRSV Nsps showed that RNF114 interacted with viral Nsp12, and that RNF114-specific anti-PRRSV effects were associated with its ubiquitin ligase activity, which involves K27-linked polyubiquitination and degradation of Nsp12 through a proteasome-dependent pathway. These findings identified RNF114 as a critical regulator of PRRSV replication and offer insights into the roles of Nsp12 in PRRSV pathogenesis. [ABSTRACT FROM AUTHOR]