SIRT1 maintains bone homeostasis by regulating osteoblast glycolysis through GOT1.

The silent information regulator T1 (SIRT1) is linked to longevity and is a crucial mediator of osteoblast function. We investigated the direct role of Sirt1 during bone modeling and remodeling stages in vivo using Tamoxifen-inducible osteoblast-specific Sirt1 conditional knockout (cKO) mice. cKO mice exhibited lower trabecular and cortical bone mass in the distal femur. These phenotypes were coupled with lower bone formation and bone resorption. Metabolomics analysis revealed that the metabolites involved in glycolysis were significantly decreased in cKO mice. Further analysis of the quantitative acetylome revealed 11 proteins with upregulated acetylation levels in both the femur and calvaria of cKO mice. Cross-analysis identified four proteins with the same upregulated lysine acetylation site in both the femur and calvaria of cKO mice. A combined analysis of the metabolome and acetylome, as well as immunoprecipitation, gene knockout, and site-mutation experiments, revealed that Sirt1 deletion inhibited glycolysis by directly binding to and increasing the acetylation level of Glutamine oxaloacetic transaminase 1 (GOT1). In conclusion, our study suggested that Sirt1 played a crucial role in regulating osteoblast metabolism to maintain bone homeostasis through its deacetylase activity on GOT1. These findings provided a novel insight into the potential targeting of osteoblast metabolism for the treatment of bone-related diseases.

Genome-wide association study reveals genetic loci for ten trace elements in foxtail millet (Setaria italica).

KEY MESSAGE: One hundred and fifty-five QTL for trace element concentrations in foxtail millet were identified using a genome-wide association study, and a candidate gene associated with Ni-Co-Cr concentrations was detected. Foxtail millet (Setaria italica) is an important regional crop known for its rich mineral nutrient content, which has beneficial effects on human health. We assessed the concentrations of ten trace elements (Ba, Co, Cr, Cu, Fe, Mn, Ni, Pb, Sr, and Zn) in the grain of 408 foxtail millet accessions. Significant differences in the concentrations of five elements (Ba, Co, Ni, Sr, and Zn) were observed between two subpopulations of spring- and summer-sown foxtail millet varieties. Moreover, 84.4% of the element pairs exhibited significant correlations. To identify the genetic factors influencing trace element accumulation, a comprehensive genome-wide association study was conducted, identifying 155 quantitative trait locus (QTL) for the ten trace elements across three different environments. Among them, ten QTL were consistently detected in multiple environments, including qZn2.1, qZn4.4, qCr4.1, qFe6.3, qFe6.5, qCo6.1, qPb7.3, qPb7.5, qBa9.1, and qNi9.1. Thirteen QTL clusters were detected for multiple elements, which partially explained the correlations between elements. Additionally, the different concentrations of five elements between foxtail millet subpopulations were caused by the different frequencies of high-concentration alleles associated with important marker-trait associations. Haplotype analysis identified a candidate gene SETIT_036676mg associated with Ni accumulation, with the GG haplotype significantly increasing Ni-Co-Cr concentrations in foxtail millet. A cleaved amplified polymorphic sequence marker (cNi6676) based on the two haplotypes of SETIT_036676mg was developed and validated. Results of this study provide valuable reference information for the genetic research and improvement of trace element content in foxtail millet.

Pseudorabies virus UL38 attenuates the cGAS-STING signaling pathway by recruiting Tollip to promote STING for autophagy degradation.

Natural immunity is the first defense line of the host immune system, which plays a significant role in combating foreign pathogenic microorganisms. The IFN-ß (interferon-beta) signaling pathway, being a typical example of innate immunity, plays a vital function. This study aimed to elucidate the function of pseudorabies virus (PRV) UL38 protein (unique long region 38) in suppressing the activation of the IFN-ß signaling pathway. The findings from our study indicate that the PRV UL38 protein effectively hampers the activation of IFN-ß by poly (dA: dT) (poly(deoxyadenylic-deoxythymidylic)) and 2'3'-cGAMP (2'-3'-cyclic GMP-AMP). Furthermore, UL38 exhibits spatial co-localization with STING (stimulator of interferon genes) and effectively hinders STING dimerization. Subsequently, STING was downgraded to suppress the production of IFN-ß and ISGs (interferon stimulated genes). Immunoprecipitation analysis revealed that the interaction between UL38 and STING, which subsequently initiated the degradation of STING via selective autophagy mediated by TOLLIP (toll interacting protein). To summarize, this research elucidates the function of UL38 in counteracting the cGAS (cGAMP synthase)-STING-induced IFN-ß pathway. The PRV UL38 protein may attenuate the activation of IFN-ß as a means of regulating the virus's persistence in the host.

Discovery of novel amide derivatives against VEGFR-2/tubulin with potent antitumor and antiangiogenic activity.

Dual-target agents have more advantages than drug combinations for cancer treatment. Here, we designed and synthesized a series of novel VEGFR-2/tubulin dual-target inhibitors through a molecular hybridization strategy, and the activities of all the synthesized compounds were tested against tubulin and VEGFR-2. Among which, compound 19 exhibited strong potency against tubulin and VEGFR-2, with IC50 values of 0.76 ± 0.11 µM and 15.33 ± 2.12 nM, respectively. Additionally, compound 19 not only had significant antiproliferative effects on a series of human cancer cell lines, especially MGC-803 cells (IC50 = 0.005 ± 0.001 µM) but also overcame drug resistance in Taxol-resistant MGC-803 cells, with an RI of 1.8. Further studies showed that compound 19 could induce tumor cell apoptosis by reducing the mitochondrial membrane potential, increasing the level of ROS, facilitating the induction of G2/M phase arrest, and inhibiting the migration and invasion of tumor cells in a dose-dependent manner. In addition, compound 19 also exhibits potent antiangiogenic effects by blocking the VEGFR-2/PI3K/AKT pathway and inhibiting the tubule formation, invasion, and migration of HUVECs. More importantly, compound 19 demonstrated favorable pharmacokinetic profiles, robust in vivo antitumor efficacy, and satisfactory safety profiles. Overall, compound 19 can be used as a lead compound for the development of tubulin/VEGFR-2 dual-target inhibitors.

N-Acetylcysteine assists muscle development in offspring of mice subjected to maternal heat stress during pregnancy.

BACKGROUND: Heat stress (HS) has been shown to affect reproductive performance and muscle development negatively in animals. N-Acetylcysteine (NAC) plays a pivotal role in enhancing the antioxidant performance in animals as a recognized antioxidant. The present study assesses the potential of NAC to modulate the reproductive performance and antioxidant function in pregnant mice exposed to HS. The role of NAC in muscle development of offspring mice was also explored. RESULTS: The results showed that NAC supplementation from day 12 to day 18 of gestation increased the number of litters and enhanced the antioxidant function in pregnant mice under HS exposure. It improved the weight and body condition significantly in the offspring mice (P < 0.05). The alleviation of HS-induced muscle impairment with NAC was consistent with the alleviation of apoptosis, the enrichment of the proliferation and differentiation in the offspring mice muscle. N-Acetylcysteine also reversed HS-induced reduction in the cross-sectional area of the leg muscle and increased the proportion of myosin heavy chain IIx (MYHCIIx) in the muscle fiber. CONCLUSION: The results of the present study support the use of NAC at a dose of 100 mg kg-1 body weight as supplement for protecting the offspring derived from pregnant mice exposed to HS from muscle impairment by accelerating proliferation and differentiation. © 2024 Society of Chemical Industry.

Meta-analysis comparing different ultrasound detection methods to accurately assess wound healing and scar formation after caesarean section.

The accurate assessment of wound healing post-caesarean section, especially in twin pregnancies, remains a pivotal concern in obstetrics, given its implications for maternal health and recovery. Traditional methods, including conventional abdominal ultrasonography (CU), have been challenged by the advent of transvaginal ultrasonography (TU), offering potentially enhanced sensitivity and specificity. This meta-analysis directly compares the efficacy of TU and CU in evaluating wound healing and scar formation, crucial for optimizing postoperative care. Results indicate that TU is associated with significantly better outcomes in wound healing, demonstrated by lower REEDA scores (SMD = -20.56, 95% CI: [-27.34.20, -13.77], p < 0.01), and in scar formation reduction, evidenced by lower Manchester Scar Scale scores (SMD = -25.18, 95% CI: [-29.98, -20.39], p < 0.01). These findings underscore the potential of integrating TU into routine post-caesarean evaluation protocols to enhance care quality and patient recovery.

[Association between infant and young child feeding indicators and the nutritional status of children aged 6-23 months in rural areas of Hunan Province in 2019].

OBJECTIVE: To estimate the status of complementary feeding among infants and young children aged 6-23 months in rural areas of Hunan Province. The association between infant and young child feeding indicators and child undernutrition were assessed. METHODS: A total of 1220 infants and young children aged 6-23 months from 24 investigated places of 6 cities in Hunan Province were selected by multi-stage stratified sampling for physical measurement, hemoglobin(Hb) test and caregiver interview. Complementary diet was analyzed according to the World Health Organization's definition of infant and young child feeding indicators. Z-scores were used to elevate nutrition status. Logistic regression models were used to explore the influencing factors of the nutritional status. RESULTS: The prevalence rates of underweight, stunting, wasting, overweight, obesity and anemia were 3.6%, 4.8%, 2.7%, 10.5%, 2.0% and 16.3%. The percentage of infants and young children aged 6-23 months in rural areas of Hunan Province who get minimum dietary diversity, minimum meal frequency, and minimum acceptable diet was 43.3%, 68.5% and 28.1%. None of the individual infant and young child feeding indicators showed significant association with undernutrition, except minimum meal frequency for obesity and anemia. CONCLUSION: The nutritional status of infants and young children in rural areas of Hunan Province has improved, but the anemia problem is still serious. Complementary feeding frequency is closely associated with anemia for infants and young children.

L-leucine promotes the synthesis of milk protein and milk fat in bovine mammary epithelial cells through the AKT/mTOR signaling pathway under hypoxic conditions.

Hypoxia stress has been demonstrated to impede animal embryonic development, spermatogenesis, and lactation, leading to decreased animal production performance. However, the impact of hypoxia-induced activation of hypoxia inducible factor-1 (HIF-1) signaling on milk protein and fat synthesis remains unclear. L-leucine, a branched-chain amino acid, is known to modulate milk protein and fat synthesis. Therefore, our study aimed to evaluate the effect of L-leucine on milk protein and fat synthesis under hypoxic conditions and shed light on the molecular mechanism using an in vitro model. The results indicated that hypoxia treatment significantly decreased the synthesis of α-casein and ß-casein, as well as inhibited factors related to milk fat synthesis in bovine mammary epithelial cells (MAC-T). Additionally, hypoxia stress suppressed the activities of the mammalian target of rapamycin (mTOR) and protein kinase B (AKT). Interfering with HIF-1α significantly reversed the expression of AKT, mTOR and factors related to milk synthesis. Importantly, supplementation with L-leucine activated AKT/mTOR signaling, thereby enhancing milk protein and fat synthesis in MAC-T cells to some extent. In conclusion, these findings suggest that HIF-1 signaling plays an important role in milk synthesis and that L-leucine may stimulate the synthesis of milk protein and fat by activating the AKT/mTOR signaling pathway under hypoxic conditions, making it a potential additive for promoting milk synthesis inhibited by hypoxia.

New perspective of small-molecule antiviral drugs development for RNA viruses.

High variability and adaptability of RNA viruses allows them to spread between humans and animals, causing large-scale infectious diseases which seriously threat human and animal health and social development. At present, AIDS, viral hepatitis and other viral diseases with high incidence and low cure rate are still spreading around the world. The outbreaks of Ebola, Zika, dengue and in particular of the global pandemic of COVID-19 have presented serious challenges to the global public health system. The development of highly effective and broad-spectrum antiviral drugs is a substantial and urgent research subject to deal with the current RNA virus infection and the possible new viral infections in the future. In recent years, with the rapid development of modern disciplines such as artificial intelligence technology, bioinformatics, molecular biology, and structural biology, some new strategies and targets for antivirals development have emerged. Here we review the main strategies and new targets for developing small-molecule antiviral drugs against RNA viruses through the analysis of the new drug development progress against several highly pathogenic RNA viruses, to provide clues for development of future antivirals.

Transcriptome Analysis of Key Genes Involved in the Initiation of Spermatogonial Stem Cell Differentiation.

PURPOSE: The purpose of this study was to screen the genes and pathways that are involved in spermatogonia stem cell (SSC) differentiation regulation during the transition from Aundiff to A1. Methods: RNA sequencing was performed to screen differentially expressed genes at 1 d and 2 d after SSC differentiation culture. KEGG pathway enrichment and GO function analysis were performed to reveal the genes and pathways related to the initiation of early SSC differentiation. RESULTS: The GO analysis showed that Rpl21, which regulates cell differentiation initiation, significantly increased after 1 day of SSC differentiation. The expressions of Fn1, Cd9, Fgf2, Itgb1, Epha2, Ctgf, Cttn, Timp2 and Fgfr1, which are related to promoting differentiation, were up-regulated after 2 days of SSC differentiation. The analysis of the KEGG pathway revealed that RNA transport is the most enriched pathway 1 day after SSC differentiation. Hspa2, which promotes the differentiation of male reproductive cells, and Cdkn2a, which participates in the cell cycle, were significantly up-regulated. The p53 pathway and MAPK pathway were the most enriched pathways 2 days after SSC differentiation. Cdkn1a, Hmga2, Thbs1 and Cdkn2a, microRNAs that promote cell differentiation, were also significantly up-regulated. CONCLUSIONS: RNA transport, the MAPK pathway and the p53 pathway may play vital roles in early SSC differentiation, and Rpl21, Fn1, Cd9, Fgf2, Itgb1, Epha2, Ctgf, Cttn, Timp2, Fgfr1, Hspa2, Cdkn2a, Cdkn1a, Hmga2 and Thbs1 are involved in the initiation of SSC differentiation. The findings of this study provide a reference for further revelations of the regulatory mechanism of SSC differentiation.

Optimization of the dosage of chopped basalt fibers in asphalt pavement surface course materials for semi-rigid base with functional requirements.

How to select suitable pavement materials for asphalt pavements according to the functional requirements of layers is still the focus of research by scholars in various countries. However, their effectiveness in combating high-temperature rutting and fatigue cracking in middle and lower layers is limited. To address this issue, a study optimized the incorporation of basalt fibers in different layers to improve road performance based on design specifications. Nine asphalt pavement structures with varying amounts of basalt fibers were assessed using an orthogonal test method. The optimal structure was determined considering factors such as fatigue life and overloading using the finite element method for modeling. Results showed that fiber dosage had a minimal impact on road surface bending subsidence and the location of tensile strain in the lower layer. Shear stresses were concentrated mainly at the outer edges of loads. Optimal dosages of basalt fiber were determined for different layers: 0.3% for the upper layer, 0.1% for the middle layer, and 0.3% for the lower layer. The optimal structure consists of a strong base with a thin-surfaced semi-rigid base layer, with 0.3% for the upper layer and 0.1% for the middle layer. This study provided valuable insights into designing basalt fiber asphalt pavement structures.

RTC_TongueNet: An improved tongue image segmentation model based on DeepLabV3.

Objective: Tongue segmentation as a basis for automated tongue recognition studies in Chinese medicine, which has defects such as network degradation and inability to obtain global features, which seriously affects the segmentation effect. This article proposes an improved model RTC_TongueNet based on DeepLabV3, which combines the improved residual structure and transformer and integrates the ECA (Efficient Channel Attention Module) attention mechanism of multiscale atrous convolution to improve the effect of tongue image segmentation. Methods: In this paper, we improve the backbone network based on DeepLabV3 by incorporating the transformer structure and an improved residual structure. The residual module is divided into two structures and uses different residual structures under different conditions to speed up the frequency of shallow information mapping to deep network, which can more effectively extract the underlying features of tongue image; introduces ECA attention mechanism after concat operation in ASPP (Atrous Spatial Pyramid Pooling) structure to strengthen information interaction and fusion, effectively extract local and global features, and enable the model to focus more on difficult-to-separate areas such as tongue edge, to obtain better segmentation effect. Results: The RTC_TongueNet network model was compared with FCN (Fully Convolutional Networks), UNet, LRASPP (Lite Reduced ASPP), and DeepLabV3 models on two datasets. On the two datasets, the MIOU (Mean Intersection over Union) and MPA (Mean Pixel Accuracy) values of the classic model DeepLabV3 were higher than those of FCN, UNet, and LRASPP models, and the performance was better. Compared with the DeepLabV3 model, the RTC_TongueNet network model increased MIOU value by 0.9% and MPA value by 0.3% on the first dataset; MIOU increased by 1.0% and MPA increased by 1.1% on the second dataset. RTC_TongueNet model performed best on both datasets. Conclusion: In this study, based on DeepLabV3, we apply the improved residual structure and transformer as a backbone to fully extract image features locally and globally. The ECA attention module is combined to enhance channel attention, strengthen useful information, and weaken the interference of useless information. RTC_TongueNet model can effectively segment tongue images. This study has practical application value and reference value for tongue image segmentation.

Histone H1.2 Inhibited EMCV Replication through Enhancing MDA5-Mediated IFN-ß Signaling Pathway.

Histone H1.2 is a member of the linker histone family, which plays extensive and crucial roles not only in the regulation of chromatin dynamics, cell cycle, and cell apoptosis, but also in viral diseases and innate immunity response. Recently, it was discovered that H1.2 regulates interferon-ß and inhibits influenza virus replication, whereas its role in other viral infections is poorly reported. Here, we first found the up-regulation of H1.2 during Encephalomyocarditis virus (EMCV) infection, implying that H1.2 was involved in EMCV infection. Overexpression of H1.2 inhibited EMCV proliferation, whereas knockdown of H1.2 showed a significant promotion of virus infection in HEK293T cells. Moreover, we demonstrated that overexpression of H1.2 remarkably enhanced the production of EMCV-induced type I interferon, which may be the crucial factor for H1.2 proliferation-inhibitory effects. We further found that H1.2 up-regulated the expression of the proteins of the MDA5 signaling pathway and interacted with MDA5 and IRF3 in EMCV infection. Further, we demonstrated that H1.2 facilitated EMCV-induced phosphorylation and nuclear translocation of IRF3. Briefly, our research uncovers the mechanism of H1.2 negatively regulating EMCV replication and provides new insight into antiviral targets for EMCV.

Mammalian reovirus µ1 protein attenuates RIG-I and MDA5-mediated signaling transduction by blocking IRF3 phosphorylation and nuclear translocation.

Mammalian reovirus (MRV) is a non-enveloped, gene segmented double-stranded RNA (dsRNA) virus. It is an important zoonotic pathogen that infects many mammals and vertebrates that act as natural hosts and causes respiratory and digestive tract diseases. Studies have reported that RIG-I and MDA5 in the innate immune cytoplasmic RNA-sensing RIG-like receptor (RLR) signaling pathway can recognize dsRNA from MRV and promote antiviral type I interferon (IFN) responses. However, the mechanism by which many MRV-encoded proteins evade the host innate immune response remains unclear. Here, we show that exogenous µ1 protein promoted the proliferation of MRV in vitro, while knockdown of MRV µ1 protein expression by shRNA could impair MRV proliferation. Specifically, µ1 protein inhibited MRV or poly(I:C)-induced IFN-ß expression, and attenuated RIG-I/MDA5-mediated signaling axis transduction during MRV infection. Importantly, we found that µ1 protein significantly decreased IFN-ß mRNA expression induced by MDA5, RIG-I, MAVS, TBK1, IRF3(5D), and degraded the protein expression of exogenous MDA5, RIG-I, MAVS, TBK1 and IRF3 via the proteasomal and lysosomal pathways. Additionally, we show that µ1 protein can physically interact with MDA5, RIG-I, MAVS, TBK1, and IRF3 and attenuate the RIG-I/MDA5-mediated signaling cascades by blocking the phosphorylation and nuclear translocation of IRF3. In conclusion, our findings reveal that MRV outer capsid protein µ1 is a key factor in antagonizing RLRs signaling cascades and provide new strategies for effective prevention and treatment of MRV infection.

Pseudorabies virus VHS protein abrogates interferon responses by blocking NF-κB and IRF3 nuclear translocation.

Herpesviruses antagonize host antiviral responses through a myriad of molecular strategies culminating in the death of the host cells. Pseudorabies virus (PRV) is a significant veterinary pathogen in pigs, causing neurological sequalae that ultimately lead to the animal's demise. PRV is known to trigger apoptotic cell death during the late stages of infection. The virion host shutdown protein (VHS) encoded by UL41 plays a crucial role in the PRV infection process. In this study, we demonstrate that UL41 inhibits PRV-induced activation of inflammatory cytokine and negatively regulates the cGAS-STING-mediated antiviral activity by targeting IRF3, thereby inhibiting the translocation and phosphorylation of IRF3. Notably, mutating the conserved amino acid sites (E192, D194, and D195) in the RNase domain of UL41 or knocking down UL41 inhibits the immune evasion of PRV, suggesting that UL41 may play a crucial role in PRV's evasion of the host immune response during infection. These results enhance our understanding of how PRV structural proteins assist the virus in evading the host immune response.

2-week prevalence and associated factors of fever, diarrhea, and coexisting fever and diarrhea among children aged 6-23 months in rural Hunan Province.

Fever and diarrhea are key causes of malnutrition, growth and development disorders, and death among children. At present, most studies on the associated factors of fever and diarrhea in children are concentrated in African and South Asian countries, but relevant research in China is very limited. This study was aimed to analyze the two-week prevalence of fever, diarrhea, and coexisting fever and diarrhea among children aged 6-23 months in rural areas of Hunan Province and to explore the associated factors. The survey data of the Nutrition Improvement Program for Children in Poor Areas (NIPCPA) from 2016 to 2023 was used here. NIPCPA is a cross-sectional survey completed annually in Hunan to collect children's nutrition and health indicators. The two-week prevalence rates of fever, diarrhea, and coexisting fever and diarrhea among children aged 6-23 months were 12.2% (2066/16,985), 9.6% (1634/16,985), and 3.2% (542/16,985), respectively. Multivariate logistic regression analysis showed the risks of fever, diarrhea, and coexisting fever and diarrhea were higher among younger children. The high educational level of caregivers, effective consumption of Yingyangbao (a complementary food supplement containing iron, zinc, calcium, vitamins A, D, B1, B2, B12, folic acid, and other micronutrients), and complementary feeding meeting minimum dietary diversity and meeting minimum acceptable diet were protective factors against fever in children, with adjusted odds ratios (aORs) of 0.87 (95%CI: 0.78-0.98), 0.78 (0.69-0.87), 0.73 (0.65-0.82), and 0.74 (0.66-0.84), respectively. Effective consumption of Yingyangbao, and complementary feeding meeting the minimum dietary diversity and meeting minimum acceptable diet were protective factors against diarrhea in children, with aORs of 0.72 (95%CI: 0.63-0.83), 0.79 (0.70-0.91), and 0.80 (0.70-0.92), respectively. Effective consumption of Yingyangbao, and complementary feeding meeting the minimum dietary diversity and meeting minimum acceptable diet were protective factors against coexisting fever and diarrhea among children, with aORs of 0.53 (95%CI: 0.43-0.66), 0.71 (0.58-0.89), and 0.70 (0.56-0.88), respectively. Fever, diarrhea, and the coexisting fever and diarrhea affect one in eight, one in ten, and one in thirty children respectively in rural areas of Hunan. Effective interventions should be actively taken, such as improving the education level of caregivers, enhancing their scientific feeding skills for children, and promoting children's compliance with Yingyangbao consumption, to further reduce the prevalence of fever and diarrhea in children.

Mapping of dynamic quantitative trait loci for plant height in a RIL population of foxtail millet (Setaria italica L.).

Plant height (PH) is a crucial trait for strengthening lodging resistance and boosting yield in foxtail millet. To identify quantitative trait loci (QTL) and candidate genes associated with PH, we first developed a genetic map using a recombinant inbred line (RIL) population derived from a cross between Aininghuang and Jingu 21. Then, PH phenotyping data and four variations of best linear unbiased prediction (BLUP) were collected from nine environments and three development stages. Next, QTL mapping was conducted using both unconditional and conditional QTL methods. Subsequently, candidate genes were predicted via transcriptome analysis of parental samples at three developmental stages. The results revealed that the genetic map, based on re-sequencing, consisted of 4,360 bin markers spanning 1,016.06 cM with an average genetic distance of 0.23 cM. A total of 19 unconditional QTL, accounting for 5.23%-35.36% of the phenotypic variation explained (PVE), which included 7 major and 4 stable QTL, were identified. Meanwhile, 13 conditional QTL, explaining 5.88%-40.35% of PVE, including 5 major and 3 stable QTL, were discovered. Furthermore, four consistent and stable QTL were identified. Finally, eight candidate genes were predicted through RNA-seq and weighted gene co-expression network analysis (WGCNA). Those findings provide a crucial foundation for understanding the genetic mechanisms underlying PH development and facilitate molecular marker-assisted breeding of ideal plant types in foxtail millet.

Mammalian orthoreovirus capsid protein σ3 antagonizes RLR-mediated antiviral responses by degrading MAVS.

Mammalian orthoreovirus (MRV) outer capsid protein σ3 is a multifunctional protein containing a double-stranded RNA-binding domain, which facilitates viral entry and assembly. We reasoned that σ3 has an innate immune evasion function. Here, we show that σ3 protein localizes in the mitochondria and interacts with mitochondrial antiviral signaling protein (MAVS) to activate the intrinsic mitochondria-mediated apoptotic pathway. Consequently, σ3 protein promotes the degradation of MAVS through the intrinsic caspase-9/caspase-3 apoptotic pathway. Moreover, σ3 protein can also inhibit the expression of the components of the RNA-sensing retinoic acid-inducible gene (RIG)-like receptor (RLR) signaling pathway to block antiviral type I interferon responses. Mechanistically, σ3 inhibits RIG-I and melanoma differentiation-associated gene 5 expression is independent of its inhibitory effect on MAVS. Overall, we demonstrate that the MRV σ3 protein plays a vital role in negatively regulating the RLR signaling pathway to inhibit antiviral responses. This enables MRV to evade host defenses to facilitate its own replication providing a target for the development of effective antiviral drugs against MRV. IMPORTANCE: Mammalian orthoreovirus (MRV) is an important zoonotic pathogen, but the regulatory role of its viral proteins in retinoic acid-inducible gene-like receptor (RLR)-mediated antiviral responses is still poorly understood. Herein, we show that MRV σ3 protein co-localizes with mitochondrial antiviral signaling protein (MAVS) in the mitochondria and promotes the mitochondria-mediated intrinsic apoptotic pathway to cleave and consequently degrade MAVS. Furthermore, tryptophan at position 133 of σ3 protein plays a key role in the degradation of MAVS. Importantly, we show that MRV outer capsid protein σ3 is a key factor in antagonizing RLR-mediated antiviral responses, providing evidence to better unravel the infection and transmission mechanisms of MRV.