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Biology subjects

Su, J.

Publications and source records attributed to Su, J..

At least 163 records · Page 9Linked to original sources

RANKL from Bone Marrow Adipocytes Regulates Osteoclast Formation and Bone Loss in Mice

Receptor activator of NF-{kappa}B ligand (RANKL) is essential for osteoclast formation and bone remodeling. Nevertheless, the cellular source of RANKL for osteoclastogenesis has not been fully uncovered. Different from peripheral adipose tissue, bone marrow (BM) adipose lineage cells originate from bone marrow mesenchymal stromal cells(BMSCs). Here we demonstrate that adiponectin promoter-driven Cre expression (AdipoqCre) can target bone marrow adipose lineage cells. We cross the AdipoqCre mice with ranklfl/fl mice to conditionally delete RANKL from BM adipose lineage cells. Conditional deletion of RANKL increases cancellous bone mass of long bones in mice by reducing the formation of trabecular osteoclasts and inhibiting bone resorption but does not affect cortical bone thickness or resorption of calcified cartilage. AdipoqCre; ranklfl/fl mice exhibit resistance to estrogen deficiency and rosiglitazone (ROS) induced trabecular bone loss but show bone loss induced by unloading. BM adipose lineage cells therefore represent an essential source of RANKL for the formation of trabecula osteoclasts and resorption of cancellous bone during remodeling under physiological and pathological conditions. Targeting bone marrow adiposity is a promising way of preventing pathological bone loss.

cell biology↗

The pleiotropic effects of the MNK1/2-eIF4E axis support immune suppression and metastasis in a model of postpartum breast cancer.

PurposeBreast cancer diagnosed within 10 years following childbirth is defined as postpartum breast cancer (PPBC) and is highly metastatic. Interactions between immune cells and other stromal cells within the involuting mammary gland are fundamental in facilitating an aggressive tumor phenotype. The MNK1/2-eIF4E axis promotes the translation of pro-metastatic mRNAs in tumor cells, but its role in modulating the function of non-tumor cells in the PPBC microenvironment, and in particular its activity in human PPBC, has not been explored. Experimental designWe used a combination of in vivo PPBC models and in vitro assays to study the effects of phospho-eIF4E deficiency on the pro-tumor function of select cells of the TME. Furthermore, we employed Imaging Mass Cytometry on PPBC and non-PPBC patient samples, to chart the expression of the MNK1/2-eIF4E axis components in the TME. ResultsHere, we show that phospho-eIF4E deficient (eIF4ES209A) PPBC mice are protected against lung metastasis and reveal differences in the lung immune microenvironment of the WT and eIF4ES209A mice. Moreover, we show that the expression of fibroblast-derived IL-33, an alarmin known to induce invasion, was repressed upon MNK1/2-eIF4E axis inhibition. Imaging Mass Cytometry results indicated that human PPBC contain phospho-eIF4E high-expressing tumor cells and CD8+ T cells displaying an activated dysfunctional phenotype. Finally, we block lung metastasis in PPBC mice, using combined MNK1/2 inhibition and anti-PD-1 therapy. ConclusionsThese findings implicate the involvement of the MNK1/2-eIF4E axis during PPBC metastasis and suggest a promising immunomodulatory route to enhance the efficacy of immunotherapy by blocking phospho-eIF4E. Translational relevancePostpartum breast cancer (PPBC) is highly aggressive. It is hypothesized that involution-induced changes in the postpartum breast microenvironment, which include an influx of inflammatory immune cells and activation of resident fibroblasts, facilitate the invasiveness of an existing neoplasm. We used imaging mass cytometry to do an in-depth profiling of the MNK1-eIF4E axis in the TME of a unique cohort of PPBC and non-PPBC patients. We observed patterns of phospho-eIF4E in non-tumor cells that were specific to the TME of PPBC. We also noted that the CD8+ T cells present in PPBC express an activated dysfunctional phenotype characterized by the co-expression of HLA-DR and PD-1. This study represents a first look at the expression of the MNK1-eIF4E axis in the stromal cells of metastatic breast cancer and has therapeutic implications as we show, in an animal model of PPBC, that MNK1/2 inhibition can be used to sensitize tumors to anti-PD1 immunotherapy.

cancer biology↗

Opposing functions of the plant TOPLESS gene family during SNC1-mediated autoimmunity

Regulation of the plant immune system is important for controlling the specificity and amplitude of responses to pathogens and in preventing growth-inhibiting autoimmunity that leads to reductions in plant fitness. In previous work, we reported that SRFR1, a negative regulator of effector-triggered immunity, interacts with SNC1 and EDS1. When SRFR1 is non-functional in the Arabidopsis accession Col-0, SNC1 levels increase, causing a cascade of events that lead to autoimmunity phenotypes. Previous work showed that some members of the transcriptional co-repressor family TOPLESS interact with SNC1 to repress negative regulators of immunity. Therefore, to explore potential connections between SRFR1 and TOPLESS family members, we took a genetic approach that examined the effect of each TOPLESS member in the srfr1 mutant background. The data indicated that an additive genetic interaction exists between SRFR1 and two members of the TOPLESS family, TPR2 and TPR3, as demonstrated by increased stunting and elevated PR2 expression in srfr1 tpr2 and srfr1 tpr2 tpr3 mutants. Furthermore, the tpr2 mutation intensifies autoimmunity in the auto-active snc1-1 mutant, indicating a novel role of these TOPLESS family members in negatively regulating SNC1-dependent phenotypes. This negative regulation can also be reversed by overexpressing TPR2 in the srfr1 tpr2 background. Thus, this work uncovers diverse functions of individual members of the TOPLESS family in Arabidopsis and provides evidence for the additive effect of transcriptional and post-transcriptional regulation of SNC1. Author SummaryThe immune system is a double-edged sword that affords organisms with protection against infectious diseases but can also lead to negative effects if not properly controlled. Plants only possess an innate antimicrobial immune system that relies on rapid upregulation of defenses once immune receptors detect the presence of microbes. Plant immune receptors known as resistance proteins play a key role in rapidly triggering defenses if pathogens breach other defenses. A common model of unregulated immunity in the reference Arabidopsis variety Columbia-0 involves a resistance gene called SNC1. When the SNC1 protein accumulates to unnaturally high levels or possesses auto-activating mutations, the visible manifestations of immune overactivity include stunted growth and low biomass and seedset. Consequently, expression of this gene and accumulation of the encoded protein are tightly regulated on multiple levels. Despite careful study the mechanisms of SNC1 gene regulation are not fully understood. Here we present data on members of the well-known TOPLESS family of transcriptional repressors. While previously characterized members were shown to function in indirect activation of defenses, TPR2 and TPR3 are shown here to function in preventing high defense activity. This study therefore contributes to the understanding of complex regulatory processes in plant immunity.

plant biology↗

Genetic determinants of wheat resistance to common root rot (spot blotch) and Fusarium crown rot

Due to soil changes, high density planting, and the use of straw-returning methods, wheat common root rot (spot blotch), Fusarium crown rot (FCR), and sharp eyespot (sheath blight) have become severe threats to global wheat production. Only a few wheat genotypes show moderate resistance to these root and crown rot fungal diseases, and the genetic determinants of wheat resistance to these devastating diseases are poorly understood. This review summarizes recent results of genetic studies of wheat resistance to common root rot, Fusarium crown rot, and sharp eyespot. Wheat germplasm with relatively higher resistance are highlighted and genetic loci controlling the resistance to each disease are summarized.

genetics↗

Co-expression of Mitochondrial Genes and ACE2 in Cornea Involved in COVID-19 Infection

The Coronavirus disease 2019 (COVID-19) pandemic severely challenges public health and necessitates the need for increasing our understanding of COVID-19 pathogenesis, especially host factors facilitating virus infection and propagation. Here, the co-expression network was constructed by mapping the well-known ACE2, TMPRSS2 and host susceptibility genes implicated in COVID-19 GWAS onto a cornea, retinal pigment epithelium and lung. We found a significant co-expression module of these genes in the cornea, revealing that cornea is potential extra-respiratory entry portal of SARS-CoV-2. Strikingly, both co-expression and interaction networks show a significant enrichment in mitochondrial function, which are the hub of cellular oxidative homeostasis, inflammation and innate immune response. We identified a corneal mitochondrial susceptibility module (CMSM) of 14 mitochondrial genes by integrating ACE2 co-expression cluster and SARS-CoV-2 interactome. Gene ECSIT, as a cytosolic adaptor protein involved in inflammatory responses, exhibits the strongest correlation with ACE2 in CMSM, which has shown to be an important risk factor for SARS-CoV-2 infection and prognosis. Our co-expression and protein interaction network analysis uncover that the mitochondrial function related genes in cornea contribute to the dissection of COVID-19 susceptibility and potential therapeutic interventions.

microbiology↗

DORGE: Discovery of Oncogenes and Tumor SuppressoR Genes Using Genetic and Epigenetic Features

Comprehensive data-driven discovery of cancer driver genes, including tumor suppressor genes (TSGs) and oncogenes (OGs), is imperative for cancer prevention, diagnosis, and treatment. Although epigenetic alterations are important contributors to tumor initiation and progression, most known driver genes were identified based on genetic alterations alone, and it remains unclear to what the extent epigenetic features would facilitate the identification and characterization of cancer driver genes. Here we developed a prediction algorithm DORGE (Discovery of Oncogenes and tumor suppressoR genes using Genetic and Epigenetic features), which integrates the most comprehensive collection of tumor genetic and epigenetic data to identify TSGs and OGs, particularly those with rare mutations. DORGE identified histone modifications as strong predictors for TSGs, and it found missense mutations, super enhancer percentages, and methylation differences between cancer and normal samples as strong predictors for OGs. We extensively validated novel cancer driver genes predicted by DORGE using independent functional genomics data. We also found that the dual-functional genes, which are both TSGs and OGs predicted by DORGE, are enriched at hubs in protein-protein interaction and drug-gene networks. Overall, our study has deepened the understanding of epigenetic mechanisms in tumorigenesis and revealed a previously undetected repertoire of cancer driver genes.

bioinformatics↗

Room Temperature Isothermal Colorimetric Padlock Probe Rolling Circle Amplification for Viral RNA Detection

Seasonal flu and pandemics, which account for millions of infections and hundreds of thousands of deaths, require rapid and reliable detection mechanisms to implement preventive and therapeutic measures. Current detection methods of viral infections have limitations in speed, accuracy, accessibility, and usability. This project presents a novel, widely applicable viral diagnostic test that uses a modified version of rolling circle amplification (RCA) to be sensitive, specific, direct RNA targeted, colorimetric and operable at room temperature. We are specifically detecting the following high-impact viruses: SARS-CoV-2, Influenza A (H1N1pdm09), and Influenza B (Victoria Lineage), although our test can be adapted to any viral infection. Results using synthetic viral DNA and RNA sequences show that our diagnostic test takes approximately one hour, detects femtomolar concentrations of RNA strands, and differentiates between virus strains. We believe implementing our diagnostic test will provide faster responses to future viral-related outbreaks for quicker societal recovery.

synthetic biology↗

Cross-neutralization antibodies against SARS-CoV-2 and RBD mutations from convalescent patient antibody libraries

The emergence of coronavirus disease 2019 (COVID-19) pandemic led to an urgent need to develop therapeutic interventions. Among them, neutralizing antibodies play crucial roles for preventing viral infections and contribute to resolution of infection. Here, we describe the generation of antibody libraries from 17 different COVID-19 recovered patients and screening of neutralizing antibodies to SARS-CoV-2. After 3 rounds of panning, 456 positive phage clones were obtained with high affinity to RBD (receptor binding domain). Then the positive clones were sequenced and reconstituted into whole human IgG for epitope binning assays. After that, all 19 IgG were classified into 6 different epitope groups or Bins. Although all these antibodies were shown to have ability to bind RBD, the antibodies in Bin2 have more superiority to inhibit the interaction between spike protein and angiotensin converting enzyme 2 receptor (ACE2). Most importantly, the antibodies from Bin2 can also strongly bind with mutant RBDs (W463R, R408I, N354D, V367F and N354D/D364Y) derived from SARS-CoV-2 strain with increased infectivity, suggesting the great potential of these antibodies in preventing infection of SARS-CoV-2 and its mutations. Furthermore, these neutralizing antibodies strongly restrict the binding of RBD to hACE2 overexpressed 293T cells. Consistently, these antibodies effectively neutralized pseudovirus entry into hACE2 overexpressed 293T cells. In Vero-E6 cells, these antibodies can even block the entry of live SARS-CoV-2 into cells at only 12.5 nM. These results suggest that these neutralizing human antibodies from the patient-derived antibody libraries have the potential to become therapeutic agents against SARS-CoV-2 and its mutants in this global pandemic.

immunology↗

Combination of favorable gene haplotypes plays an important role in rice hybrid grain quality traits based on genome-wide association analysis

Yield level and grain quality determine the commercial potential of rice (Oryza sativa L.) varieties. Mining and using genes that control important rice grain quality characteristics are major tasks for plant breeders. Here, a genome-wide association study was conducted to determine the genetic bases of 12 rice grain quality traits in 113 varieties and 565 testcross hybrids. A total of 56 significant SNPs were associated with 9 of the traits in variety phenotypic, general combining ability, testcross hybrid phenotypic and mid-parental heterotic datasets, from which 45 novel loci were identified. The cumulative effects of superior alleles or favorable haplotypes of genes closest to significant quality trait-associated loci were found in the four datasets. Additionally, the favorable gene haplotypes performed better than those of superior alleles in the variety and testcross hybrid datasets. Pyramiding the favorable haplotypes of five cloned rice grain quality genes resulted in a very low amylose content and high yield in the latter. These testcross hybrids had rice grain qualities similar to their parental lines but with much higher yields. The amylose content, grain width and grain length predictions for potential hybrids among the 113 varieties using genomic selection based on the BayesB method revealed a performance trend similar to those the testcross hybrids in our study. Thus, the selection of combination of favorable rice quality-related gene haplotypes is recommended to breed hybrids with high yields and elite grain qualities.

genetics↗

The MNK1/2-eIF4E axis contributes to phenotype switching, melanoma progression, and resistance to immunotherapy.

Melanomas commonly undergo a phenotype switch, from a proliferative to an invasive state. Melanoma plasticity exhibited as phenotype switching contributes to immunotherapy resistance, however the mechanisms are not completely understood and thus therapeutically unexploited. Here, using a transgenic melanoma mouse model, we demonstrated a critical role of the MNK1/2-eIF4E axis in melanoma plasticity and resistance to immunotherapy. We showed that phospho-eIF4E deficient murine melanomas express high levels of melanocytic antigens, with similar results verified in patient melanomas. Mechanistically, we identified that phospho-eIF4E controls the translation of NGFR, a critical effector of phenotype switching. In patients with melanoma, the expression of MKNK1, the kinase for eIF4E, positively correlated with markers of immune exhaustion. Genetic ablation of phospho-eIF4E reprogrammed the immunosuppressive microenvironment, exemplified by lowered production of inflammatory factors and increased CD8+ T cell infiltrates. Blocking phospho-eIF4E, using MNK1/2 inhibitors, offers a new strategy to inhibit melanoma plasticity and improve the survival response to anti-PD-1 immunotherapy.

cancer biology↗

scLM: automatic detection of consensus gene clusters across multiple single-cell datasets

In gene expression profiling studies, including single-cell RNA-seq (scRNAseq) analyses, the identification and characterization of co-expressed genes provides critical information on cell identity and function. Gene co-expression clustering in scRNA-seq data presents certain challenges. We show that commonly used methods for single cell data are not capable of identifying co-expressed genes accurately, and produce results that substantially limit biological expectations of co-expressed genes. Herein, we present scLM, a gene co-clustering algorithm tailored to single cell data that performs well at detecting gene clusters with significant biologic context. scLM can simultaneously cluster multiple single-cell datasets, i.e. consensus clustering, enabling users to leverage single cell data from multiple sources for novel comparative analysis. scLM takes raw count data as input and preserves biological variations without being influenced by batch effects from multiple datasets. Results from both simulation data and experimental data demonstrate that scLM outperforms the existing methods with considerably improved accuracy. To illustrate the biological insights of scLM, we apply it to our in-house and public experimental scRNA-seq datasets. scLM identifies novel functional gene modules and refines cell states, which facilitates mechanism discovery and understanding of complex biosystems such as cancers. A user-friendly R package with all the key features of the scLM method is available at https://github.com/QSong-WF/scLM.

bioinformatics↗

Recombinant SARS-CoV-2 spike S1-Fc fusion protein induced high levels of neutralizing responses in nonhuman primates

The COVID-19 outbreak has become a global pandemic responsible for over 2,000,000 confirmed cases and over 126,000 deaths worldwide. In this study, we examined the immunogenicity of CHO-expressed recombinant SARS-CoV-2 S1-Fc fusion protein in mice, rabbits, and monkeys as a potential candidate for a COVID-19 vaccine. We demonstrate that the S1-Fc fusion protein is extremely immunogenic, as evidenced by strong antibody titers observed by day 7. Strong virus neutralizing activity was observed on day 14 in rabbits immunized with the S1-Fc fusion protein using a pseudovirus neutralization assay. Most importantly, in less than 20 days and three injections of the S1-Fc fusion protein, two monkeys developed higher virus neutralizing titers than a recovered COVID-19 patient in a live SARS-CoV-2 infection assay. Our data strongly suggests that the CHO-expressed SARS-CoV-2 S1-Fc recombinant protein could be a strong candidate for vaccine development against COVID-19. HighlightsO_LICHO-expressed S1-Fc protein is very immunogenic in various animals and can rapidly induce strong antibody production C_LIO_LIS1-Fc protein solicits strong neutralizing activities against live virus C_LIO_LIStable CHO cell line expressing 50 mg/L of S1-Fc and a 3,000 L Bioreactor can produce 3 million doses of human COVID-19 vaccine every 10 days, making it an accessible and affordable option for worldwide vaccination C_LI

immunology↗

Identification of a novel efficient transcriptional activation domain from Chinese fir (Cunninghamia lanceolata)

Activation domains are used as critical components of artificial gene modification tools for genetic breeding. The high efficiency of the activation domain relies on the host plant. However, no activation domain has been identified that originates from Chinese fir (Cunninghamia lanceolate). In this study, a novel strong activator was identified from the whole Chinese fir cDNA library. This plant conserved activator was named TAC 3 (Transcriptional Activation domain from Chinese fir 3). C-terminal 70 amino acids of TAC (TAC3d) have a stronger ability than the commonly used strong activation domain of the virus protein VP16, or the strong plant activation domain, EDLL, in Chinese fir. Through Dual-luciferase assay, phenomic analysis and FT (Flowering Locus T [FT]) quantification, it was shown that, TAC3d can overcome the transcriptional repression of strong plant repressors (Flowering Locus C [FLC]) when fused to its C-terminal domain, thus inhibit the repression of FT expression. In conclusion, for the first time, an activation domain has been identified from Chinese fir. TAC3, which can be used for precise gene activation in Chinese fir in the future, and its function in the plant is more powerful than the commonly used strong activation domain (such as VP16 and EDLL). HighlightTAC3 is the first transcriptional activation domain identified from Chinese fir and its function is more powerful than some commonly used strong transcriptional activators (such as VP16 and EDLL)

genetics↗

Three-dimensional regulation of HOXA cluster genes by a cis-element in hematopoietic stem cell and leukemia.

Proper gene regulation is crucial for cellular differentiation, and dysregulation of key genes can lead to diseased states such as cancer. The HOX transcription factors play such a role during hematopoiesis, and aberrant expression of certain HOXA genes is found in certain acute myeloid leukemias (AMLs). While studies have shown that these genes are targeted by a variety of mutant proteins including mutant NPM1, MLL fusions, and NUP98 fusions, little is known about how long-range 3D chromatin interactions regulate the HOXA genes in normal hematopoiesis and leukemia. Here, we report the interaction between the HOXA cluster with a [~]1.3 Mb upstream DNA methylation Canyon termed "Geneless Canyon" (GLC) in human CD34+/CD38-hematopoietic stem cells (HSCs) and AML cell lines. We show that CRISPR-Cas9 mediated deletion of the whole GLC region reduces the expression of the distal HOXA genes and compromises HSC and leukemia cells self-renewal. This long-range chromatin interaction brings the HOXA cluster in contact with the nuclear pore complex (NPC) at the nuclear periphery, which promotes HOXA gene expression and maintains HSC and leukemia cell self-renewal. These findings reveal how long-range 3D chromatin organization regulates key transcription factor genes in both normal and diseased hematopoietic cells.

genomics↗

Cellular heterogeneity-adjusted clonal methylation (CHALM) provides better prediction of gene expression

Promoter DNA methylation is a well-established mechanism of transcription repression, but its global correlation with gene expression is surprisingly weak. This weak correlation is due in part to the failure of current methylation quantification methods to consider the heterogeneity among sequenced bulk cells. Here, we introduce Cell Heterogeneity-Adjusted cLonal Methylation (CHALM) as a novel methylation quantification method. CHALM better explains the functional consequences of DNA methylation, such as its correlations with gene expression and H3K4me3. When applied to different methylation datasets, the CHALM method has uniquely detected differentially methylated genes that exhibit distinct biological functions supporting underlying mechanisms.

bioinformatics↗

Shift of maternal gut microbiome of Tibetan antelope (Pantholops hodgsonii) during the perinatal period

The maternal gut microbiome can influence and be affected by the substantial physiological changes taking place during the perinatal period. However, little information is known about the changes in the maternal gut microbiome during this period. Tibetan antelope (Pantholops hodgsonii) provide a unique system to address this issue because their summer migration cycle is synchronized with the perinatal period. We used 16S rRNA gene sequencing to generate gut microbiome profiles using fecal samples collected from female migratory Tibetan antelope. We then correlated microbiome diversity with fecal hormone metabolite concentrations of glucocorticoids (GCs) and triiodothyronine (T3) extracted from the same fecal samples. The maternal gut microbiome of Tibetan antelope was dominated by Firmicutes and Bacteroidetes. There was a clear separation in gut microbial composition by female reproductive states based on both hierarchical clustering and PCoA analyses. The shift in the maternal gut microbiome likely reflects the metabolic and immune system dynamics during the perinatal period. Overall, the microbiome diversity was higher in the late pregnancy compared to the postpartum period. The negative association between T3 and microbiome diversity may be moderated by the shift of reproductive states since the correlations disappeared when considering each reproductive state separately. Integrating the microbiome dimension, migration pattern and reproduction may have direct conservation implications as by establishing a baseline of the physiological changes during the migration/perinatal period, we can have a better understanding of the impacts of increasing human activities on the Tibetan Plateau on the reproductive health of Tibetan antelope.

zoology↗

scTPA: A web tool for single-cell transcriptome analysis of pathway activation signatures

The most fundamental challenge in current single-cell RNA-seq data analysis is functional interpretation and annotation of cell clusters. The biological pathways in distinct cell types have different activation patterns, which facilitates understanding cell functions in single-cell transcriptomics. However, no effective web tool has been implemented for single-cell transcriptomic data analysis based on prior biological pathway knowledge. Here, we introduce scTPA (http://sctpa.bio-data.cn/sctpa), which is a web-based platform providing pathway-based analysis of single-cell RNA-seq data in human and mouse. scTPA incorporates four widely-used gene set enrichment methods to estimate the pathway activation scores of single cells based on a collection of available biological pathways with different functional and taxonomic classifications. The clustering analysis and cell-type-specific activation pathway identification were provided for the functional interpretation of cell types from pathway-oriented perspective. An intuitive interface allows users to conveniently visualize and download single-cell pathway signatures. Together, scTPA is a comprehensive tool to identify pathway activation signatures for dissecting single cell heterogeneity.

genomics↗

Deoxynivalenol Promotes Porcine Epidemic Diarrhea Virus Infection and Aggravates Gut Barrier Injury

Porcine epidemic diarrhea virus (PEDV) is a highly contagious pathogenic virus that causes severe diarrhea and dehydration in pigs of all ages. Deoxynivalenol (DON), the most abundant trichothecene in food and feed, causes vomit and diarrhea in animals and human. However, whether DON exposure could affect PEDV infection remains unknown. Herein, we investigated the impacts of DON on entry and replication of PEDV, morbidity situation of piglets and the mechanisms involved. In vivo, twenty-seven piglets infected naturally with PEDV were randomly divided into three groups, receiving the basal diet containing 0, 750 and 1500 g/kg DON, respectively. We observed significant increases in the diarrhea rates, the villous injury of jejunums and the PEDV proliferation of duodenum, jejunum, ileum and mesenterium of piglets in experimental groups compared with control. Additionally, the autophagosome-like vesicles and the autophagy-related protein expressions were also increased in experimental groups. In vitro, we observed that, approximately 2 hrs post-infection, 0.1, 0.5 and 1.0 M DON promoted PEDV entry (P < 0.05) in IPEC-J2s and resulted in tight junction protein occludin internalization. Knockdown of occludin and CRISPR-Cas9-mediated knockout of LC3B indicated a vital role of autophagy-induced occludin internalization in DON-promoted PEDV entry. We also observed that, 24 hrs post-infection, a significant increase in PEDV replication after 0.1, 0.5 and 1.0 M DON treatment, along with the induction of a complete autophagy. Specifically, deletion of LC3B indicated a crucial role of autophagy in DON-promoted PEDV replication. Pretreatment with SB202190, a p38 signaling inhibitor, abolished the induction of autophagy. Furthermore, downregulation of type I interferon revealed that DON contributed PEDV to escape innate immune. Mechanistically, DON-caused innate immune escape was related to the upregulation of LC3B, which further inhibited STING phosphorylation. Taken together, DON could promote PEDV infection by inducing occludin internalization and innate immune escape via triggering p38-mediated autophagy. Author summaryPorcine epidemic diarrhea (PED), a devastating enteric disease, leads to catastrophic economic loss to the global pig industry. Its primary pathogen is the coronavirus PED virus (PEDV). Growing evidence indicates that pathogen infection is not the only factor of PED outbreaks, other non-infectious factors is also related to this disease. We guessed some ubiquitous substances, such as deoxynivalenol (DON), that lead to pig intestinal epithelial cell stress might encourage the progress and spread of PED. In the present study, the weaning piglets infected naturally with PEDV and the IPEC-J2 cell line were selected as models to explore the effects of DON on PEDV infection, morbidity and gut barrier. Our results showed that DON exposure can promote PEDV infection in vitro and in vivo, and the underlying mechanism might be related to LC3B-mediated autophagy. Our findings reveal new pathways for developing potential novel antiviral strategies against PEDV infection.

immunology↗