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Shao, N.

Publications and source records attributed to Shao, N..

7 recordsLinked to original sources

Effect of CSFV on Differential Genes of Histone Lactylation at H3K18 in the PI3K-AKT Signaling Pathway

Classical swine fever (CSF) is a highly contagious disease caused by Classical swine fever virus (CSFV), posing a serious threat to the global swine industry. This study aimed to investigate the effect of CSFV on differential genes of histone lactylation at the H3K18 site in the PI3K-AKT signaling pathway. The site with the most significant change in histone lactylation antibody level was screened by Western blot. Omics analysis was performed using CUT&Tag technology to identify differential genes in the PI3K-AKT pathway between the CSFV-infected group and the mock group, followed by validation using RT-qPCR. Functional analysis of significantly differential proteins was conducted, and the protein expression level of THBS4 was detected by Western blot. The results showed that after CSFV infection of 3D4/21 cells, the H3K18la site exhibited the most significant difference in antibody level. A total of 8,859 differential genes at the H3K18la site were identified by CUT&Tag analysis, including 6,349 up-regulated genes and 2,510 down-regulated genes. Further focusing on the PI3K-AKT signaling pathway, 10 differential genes were identified, comprising 6 up-regulated genes and 4 down-regulated genes. Compared with the control group, the mRNA expression levels of CD19, LAMA1, PDGFRA, BDNF, ANGPT4, and THBS4 were up-regulated in the CSFV-infected group, while FOXO3 and NRTN were down-regulated. Western blot results showed that the protein expression level of THBS4 increased after CSFV infection. These findings lay an important foundation for understanding the molecular mechanisms regulating viral replication and immune evasion, and have significant scientific implications and potential application value.

microbiology↗

Deep mapping of structural perturbations to energetics enables precise TCR design

Affinity optimization and cross-reactivity profiling are pivotal for T-cell receptor (TCR) engineering and immunotherapy, yet remain hindered by the vast diversity of the TCR repertoire and limited structural insights. Here, we present mpTCRai, a deep learning framework that captures the sequential characteristics of antigen presentation and recognition with high precision. Leveraging these precise structural predictions, we established a contact hotspot-based scoring mechanism that explicitly maps structural perturbations to energetic changes, yielding a strong correlation with experimental affinity (r = -0.88). In application, the model identified critical molecular switches, such as specific G-to-A substitutions, and revealed their dependence on structural context. Furthermore, it effectively distinguished functional variants from dangerous cross-reactive mutations like Y5W, thereby mitigating the risk of off-target toxicity. Guided by these insights, we computationally designed four novel A6-TCR variants, demonstrating a rational strategy for candidate selection in adult T-cell leukemia. This work establishes a unified platform integrating structural and energetic constraints to advance precise, safe TCR therapeutic design.

immunology↗

Vascularized Human Cardiac Organoids Reveal Endothelial-Cardiomyocyte Crosstalk and Mechanisms of Carfilzomib-Induced Cardiotoxicity

Human cardiac organoids (hCOs) provide a powerful platform for modeling heart development and disease, yet their lack of vasculature limits physiological relevance. Here, we generate vascularized human cardiac organoids (vhCOs) by assembling hCOs with blood vessel organoids, enabling the self-organized formation of unified tissues with extensive vascular networks and substantially enhanced cardiomyocyte (CM) maturation. Single-nucleus multiomic profiling reveals CM state resembling the 17-week human fetal heart, while endothelial cells (ECs) acquire cardiac-specific and arterial-like identities. Integrative cell-cell communication analyses and experimental validation identify CM-derived Laminin-2 as a driver of arterial EC specification, while reciprocal EFNB2 signaling from arterial ECs promotes CM maturation, uncovering bidirectional cardiac-vascular crosstalk. Modeling carfilzomib-induced cardiotoxicity in vhCOs reveals ATF4-dependent endoplasmic reticulum (ER) stress and IL8-mediated inflammatory responses that are blunted in non-vascularized hCOs. Pharmacological attenuation of ER stress alleviates carfilzomib-induced cardiotoxicity. Altogether, vhCOs provide a developmentally advanced and physiologically faithful human cardiac model.

cell biology↗

Gasdermin E couples mitochondrial damage to pyroptotic neurodegeneration in Parkinson disease

Parkinsons disease (PD) features progressive loss of nigrostriatal dopamine neurons, but how mitochondrial damage engages programmed cell death pathways remains unresolved. Here, we identify gasdermin E (GSDME), the caspase-3-activated executor of pyroptosis, as a critical mediator of neurodegeneration in toxin-based PD models. In primary neurons and SH-SY5Y cells, the mitochondrial complex I inhibitor MPTP/MPP triggered caspase-3 activation, GSDME cleavage, and lytic membrane rupture. Genetic silencing of Gsdme or its transcriptional regulator SP1 reduced neuronal death. In vivo, Gsdme deficiency preserved substantia nigra pars compacta dopaminergic neurons, improved motor performance, and mitigated anxiety- and depression-like behaviors after MPTP administration. Loss of Gsdme also dampened microglial and astrocytic activation and lowered proinflammatory cytokines in striatum and substantia nigra. Mechanistically, cleaved GSDME localized to mitochondria, disrupted membrane potential, increased reactive oxygen species, and precipitated organelle injury, thereby coupling mitochondrial dysfunction to pyroptotic cell death. These findings identify GSDME-mediated pyroptosis as a mechanistic link between mitochondrial toxicity and neuroinflammation in PD and nominate GSDME as a therapeutic entry point to slow disease progression. SignificanceHow mitochondrial injury kills dopamine neurons in Parkinsons disease is a central unresolved question. We show that the pyroptosis executor GSDME is required for neurodegeneration and neuroinflammation in MPTP models, mechanistically linking caspase-3 activation and mitochondrial damage to lytic cell death. Targeting GSDME may provide a strategy to protect vulnerable neurons in PD. Graphic Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=191 SRC="FIGDIR/small/694264v1_ufig1.gif" ALT="Figure 1"> View larger version (47K): org.highwire.dtl.DTLVardef@15364e7org.highwire.dtl.DTLVardef@57b65org.highwire.dtl.DTLVardef@1e85108org.highwire.dtl.DTLVardef@1200d34_HPS_FORMAT_FIGEXP M_FIG C_FIG HighlightsGSDME drives PD-linked neuronal loss. Silencing GSDME (or its transcriptional factor Sp1) ameliorates MPTP-triggered neuronal cell death. Genetic ablation of Gsdme is protective in the MPTP-induced PD mouse model. Gsdme-/-mice retain nigrostriatal DA neurons, show improved motor and affective behaviors, and exhibit reduced microglial and astrocytic activation and cytokines release upon MPTP treatment. Cleaved GSDME accumulates on mitochondria, collapses {Delta}{Psi}m, raises ROS, and links mitochondrial toxicity to pyroptosis, thus positioning GSDME as a tractable target to slow PD progression.

neuroscience↗

Natural Killer cell contractility and cytotoxicity is driven by TLR3 agonist-mediated TAZ cytoplasmic sequestration

The evolutionarily conserved YAP/TAZ mechano-responsive transcription cofactors regulate development and tumorigenesis. Here, we show for the first time that human natural killer (NK) cells specifically express TAZ but not YAP, and TAZ serves to limit NK cytotoxicity. The TLR3 agonist, hiltonol, was able to trigger cytoplasmic sequestration of TAZ, which increased NK cytotoxicity. Mechanistically, a low dose of hiltonol enhanced the intracellular contractility of NK cells accompanied by an increase in active RhoA and myosin light chain phosphorylation, conceivably through an increase in ERK1/2 activation-dependent ROS production. Importantly, we showed that the dissociation of LATS1 from actin upon activation of contractility, is required to sequester TAZ in the cytoplasm. Functionally, hiltonol also reduced the NK cell surface inhibitory receptors, KIR3DL1 through c-Myc inhibition and PD-1 through enhanced contractility. Direct inhibition of c-Myc promoted NK cytotoxicity against K562 lymphoblast. We corroborated our findings by coculturing hiltonol-pretreated NK cells with breast and lung cancer cells, and demonstrated increased NK-mediated cancer killing, which conceivably occurred via sequestration of TAZ to the cytoplasm which facilitated NK cytotoxicity. Our findings pave the way for ex vivo rejuvenation of NK cells for in vivo immunotherapies, which could involve a cocktail of hiltonol and c-Myc inhibitor.

cell biology↗

The kleisin subunit controls the function of meiotic cohesins by determining the mode of DNA binding and differential regulation by SCC-2 and WAPL-1

The cohesin complex plays essential roles in chromosome segregation, 3D genome organisation, and DNA damage repair through its ability to modify DNA topology. In higher eukaryotes, meiotic chromosome function, and therefore fertility, requires cohesin complexes containing meiosis-specific kleisin subunits: REC8 and RAD21L in mammals and REC-8 and COH-3/4 in C. elegans. How these complexes perform the multiple functions of cohesin during meiosis and whether this involves different modes of DNA binding or dynamic association with chromosomes is poorly understood. Combining time-resolved methods of protein removal with live imaging and exploiting the temporospatial organisation of the C. elegans germline, we show that REC-8 complexes provide sister chromatid cohesion (SCC) and DNA repair, while COH-3/4 complexes control higher-order chromosome structure. High-abundance COH-3/4 complexes associate dynamically with individual chromatids in a manner dependent on cohesin loading (SCC-2) and removal (WAPL-1) factors. In contrast, low-abundance REC-8 complexes associate stably with chromosomes, tethering sister chromatids from S-phase until the meiotic divisions. Our results reveal that kleisin identity determines the function of meiotic cohesin by controlling the mode and regulation of cohesin-DNA association, and are consistent with a model in which SCC and DNA looping are performed by variant cohesin complexes that coexist on chromosomes.

cell biology↗

Genotype 1 Japanese encephalitis virus predominates in nature in China

IntroductionJapanese encephalitis virus (JEV), in the genus Flavivirus, family Flaviviridae, is the leading cause of viral encephalitis in the Asian-Pacific region. JEV has a wide range of vector hosts, including mosquitoes, swine, and wading birds. Culex species, especially Culex tritaeniorhynchus, are the main vectors for JEV transmission. JEV has been classified into five genotypes (G1-G5). JEV G1, G3, and G5 isolates have been found in China.\n\nMethodsMore than 200,000 mosquitoes collected in 14 provinces in China from 2004 to 2016 were examined for JEV using a TaqMan real-time RT-PCR assay. The JEV envelope (E) gene was sequenced from positive pools. The nucleic acid sequences were analyzed and aligned using ClustalX ver. 2.0. Representative JEV envelope (E) gene sequences were downloaded from GenBank and compared with the newly obtained JEV sequences. MEGA 5.05 was used to generate a phylogenetic tree based on the JEV sequences.\n\nResultsMore than 200,000 mosquitoes were divided into 3107 pools to test for JEV. Of the pools, 9.04% (281/3107) were positive. The JEV obtained from mosquitoes included three genotypes (G1, G3, and G5). JEV G1 was detected from different provinces during 2004-2016. G1 was the dominant genotype circulating in nature, comprising 98.93% (278/281). JEV G3 was detected in Yunnan and Chongqing Provinces before 2010; JEV G5 was detected only in Tibet. No pools were positive for JEV G2 and G4. C. tritaeniorhynchus was the major mosquito species and the principal vector for transmitting JEV in China. The results of the TaqMan real-time RT-PCR assay and phylogenetic analysis consistently indicated that all 50 newly identified JEV sequences belonged to JEV G1.\n\nConclusionG1 is the main genotype of JEV circulating in nature in China. Some G3 and G5 were found, but no G2 or G4.\n\nAuthor summaryJapanese encephalitis virus (JEV) is a member of the genus Flavivirus, family Flaviviridae and is the major pathogen agent of Japanese encephalitis (JE) in the Asian-Pacific region. The fatality rate of JE is 20-30%. JEV consists of five genotypes (G1-G5). The predominant genotype was G3 before the 20thcentury. G1 and G3 co-circulated in China at the end of the 20thand early 21stcentury. JEV G1 is the youngest genotype and has gradually been found in many areas worldwide. Using a sensitive TaqMan real-time RT-PCR assay, this study examined 3107 pools of mosquito. The main genotype of Japanese encephalitis virus in China was G1, with some G3 and G5, but no G2 or G4. C. tritaeniorhynchus was the major mosquito species and the principal vector for transmitting JEV in China. TaqMan real-time RT-PCR assay and phylogenetic analysis consistently indicated that all 50 newly identified JEV sequences belonged to JEV G1.

molecular biology↗