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Zhang, L.

Publications and source records attributed to Zhang, L..

At least 199 records · Page 11Linked to original sources

Divergent mitochondrial and metabolic adaptations shape selective vulnerability in ALS

Neurodegenerative diseases like amyotrophic lateral sclerosis (ALS) exhibit striking cell-type selectivity, yet the basis for this vulnerability remains elusive. Here, we uncover that even closely related neurons can harbor distinct mitochondrial properties that shape their response to disease. Using TOM-Tag, a circuit-based AAV-based strategy for cell type-specific mitochondrial immunopurification from projection neurons, we performed integrative proteomic, metabolomic, transcriptomic, and functional analyses of mitochondria from ALS-vulnerable corticospinal projection neurons (CSPNs) and resilient corticothalamic projection neurons (CTPNs) in vivo. We discovered that CSPNs and CTPNs exhibit divergent mitochondrial profiles at baseline, despite sharing cortical layer and developmental origin. CTPNs were primed for antioxidant buffering and fatty acid metabolism, whereas CSPNs were enriched for oxidative phosphorylation components. In ALS, CTPNs employed mitochondrial flexibility and redox defense, whereas CSPNs exhibited respiratory failure and metabolic stress. These findings reveal that intrinsic mitochondrial programs vary even between similar neurons, and that this hidden layer of diversity may critically shape susceptibility to neurodegeneration. By enabling high-resolution access to mitochondria in defined neuronal circuits, TOM-Tag offers a powerful new lens for dissecting disease mechanisms and identifying cell-specific therapeutic targets.

neuroscience↗

Macrophage Antigen Presentation Is Unleashed by Pan-RAS Inhibition to Promote Antitumor Immunity

Pan-RAS inhibitors have emerged as potent targeted therapies designed to suppress oncogenic signaling in RAS-mutant tumors. However, whether these inhibitors possess therapeutic utility beyond tumors with intrinsic RAS dependency remains unclear. Here we show that the clinical-stage pan-RAS(ON) inhibitor RMC-6236 (Daraxonrasib) induces robust regression of NRAS-wild-type B16 tumors in immunocompetent mice, a response mediated by a mechanism independent of direct tumor-cell targeting. Instead, RMC-6236 acts by remodeling the tumor microenvironment, specifically enhancing the antigen-presenting capacity of tumor-associated macrophages through upregulated MHC-I expression. This anti-tumor efficacy is abrogated in T cell-deficient hosts, identifying a macrophage-dependent, T cell-mediated mechanism of control. Mechanistically, RMC-6236 does not directly block canonical RAS signaling in macrophages. Rather, it suppresses a Myc-Hdac2 epigenetic program, leading to enhanced histone H4 acetylation at the Nlrc5 locus and subsequent activation of the MHC-I master regulator NLRC5. Together, our findings reveal a macrophage-centered, epigenetically wired immune mechanism for pan-RAS inhibition that broadens the therapeutic scope of targeting the "undruggable" RAS pathway beyond tumor genotype towards systemic immune modulation.

immunology↗

Molecular mechanisms of mitochondrial Ca2+ exchanger NCLX

Mitochondrial Ca2+ homeostasis is maintained through coordinated influx and efflux processes, with NCLX long recognized as the primary Ca2+ extruder operating via Na+/Ca2+ exchange. Here, we report cryo-EM structures of rat NCLX in cytosolic-facing occluded and open states. The central transmembrane (TM) domain of NCLX comprises ten helices arranged in two inverted, structurally similar halves, with two -repeats forming a central ion-binding pocket. Peripheral TMs 1 and 6 are loosely associated with the core and likely mediate alternative access to this site. These structural features closely resemble those of NCXs, indicating a conserved ion exchange mechanism. While NCLX retains the canonical Ca2+-binding site, it lacks several key Na+-binding residues found in NCXs, suggesting broader ion selectivity. Consistently, cell-based Ca2+ uptake assays show that NCLX mediates Ca2+ exchange using Na+, K+, Li+, and potentially protons as counterions. Based on the structural symmetry of NCLX and its bidirectional exchange capability, we propose a matrix-facing model and an alternating-access mechanism in which TMs 1 and 6 undergo sliding motions to enable ion exchange between cytosolic and matrix sides, analogous to NCX. These findings provide a structural and mechanistic framework for understanding NCLX-mediated Ca2+ transport in mitochondria.

biophysics↗

A Chemical-Genetic Interaction Matrix Reveals Drug Mechanism and Genetic Architecture

To probe drug mechanism of action (MOA) and interrogate the genetic architecture of human cells, we carried out isogenic genome-wide CRISPR/Cas9 knockout screens against 310 diverse drugs, bioactive compounds, and stress conditions. Stringent statistical correction for gene knockout fitness defects yielded a large-scale matrix of >12,000 high confidence chemical-genetic interactions (CGIs). This dataset revealed many previously unappreciated off-target effects for well-characterized compounds and novel MOAs for uncharacterized compounds. The CGI matrix uncovered dense genetic modules that yielded new biological insights into phospholipidosis, mitotic regulation, metabolism, the DNA damage response, and mTOR signaling. The dataset allowed identification of multi-drug sensitization and resistance mechanisms, inference of gene function, elaboration of cross-process connectivity, evaluation of the cell type specificity of CGIs, prediction of chemical synergism, and extensive annotation of understudied genes. This resource provides a map of the genetic landscape in human cells and a framework to help guide drug discovery.

systems biology↗

Endothelin 2-Mediated Neuroinflammation Drives Hypertension-Associated Retinal Dysfunction

Systemic hypertension is a significant risk factor for glaucoma, a leading cause of irreversible blindness, yet the mechanistic basis connecting the two conditions remains elusive. Here, we demonstrate that hypertensive rats develop accelerated retinal degeneration characterized by retinal thinning, functional impairment, reduced perfusion, and progressive neuroinflammation. Critically, these changes occur despite persistently lower intraocular pressure (IOP), indicating an IOP-independent mechanism of pathology. Transcriptomic and biochemical analyses identified a robust activation of the retinal endothelin system, with endothelin-2 (EDN2) being the earliest and most significantly upregulated component. AAV-delivered retinal Edn2 knockdown completely restored retinal function, ameliorated neuroinflammation, and enhanced retinal blood flow in hypertensive rats. Pharmacological blockade of endothelin receptor type A (EDNRA), but not type B, replicated these protective effects without altering IOP. Our findings establish EDN2 as a central, IOP-independent driver of hypertension-associated retinal neurodegeneration and identify the endothelin-EDNRA axis as a potential therapeutic target to prevent vision loss in hypertensive patients.

neuroscience↗

Sonogenetic control of cardiomyocytes and cardiac pacing using exogenous Transient Receptor Potential A1 channels

Electronic cardiac pacemakers are the standard of care for treating arrhythmias but, even for wireless pacemakers, they require an intracardiac implant procedure and are invasive. Lead-related complications, including life-threatening infections, and limited suitability in pediatric patients restrict pacemaker use. Biological pacing has emerged as a hardware-free alternative, leveraging cell reprogramming approaches to generate pacemaker-like cardiomyocytes. Despite progress, biological strategies face challenges related to complex signaling pathways, intercellular coupling, durability of effect, efficacy, and safety. In addition, once ion channels or cells are implanted, biological pacemakers offer limited real-time programmability, whereas electronic pacemakers enable continuous adjustment of pacing output based on cardiac performance. Here we propose a hybrid approach that combines genetic sensitization with external control by exploring the feasibility of sonogenetic cardiac pacing. We express the ultrasound-sensitive ion channel hsTRPA1 in cardiomyocytes and use noninvasive ultrasound to modulate channel activity and cardiac function. Using calcium imaging, we show that hsTRPA1 potentiates ultrasound-evoked responses in cardiomyocytes. Furthermore, cardiac expression of hsTRPA1 in mice increases heart rate in response to ultrasound delivered noninvasively through the intact chest, without evidence of a thermal mechanism under the conditions tested. Together, these results establish a proof of concept for sonogenetic cardiac pacing and define an initial acoustic and genetic parameter space compatible with preserving baseline cardiac function. More broadly, this work positions sonogenetics as a minimally invasive, wireless strategy for cardiac rhythm control and motivates future optimization and safety studies toward translation.

bioengineering↗

Structure-based design of soluble prefusion-stabilized herpes simplex virus type 2 glycoprotein B antigens

Herpes simplex virus type 2 (HSV-2) causes genital herpes through latent infection and periodic reactivation. Although antivirals alleviate symptoms, no prophylactic or therapeutic vaccines have been licensed. Glycoprotein B (gB) is a class III fusion protein that mediates entry by irreversibly transitioning from a metastable prefusion conformation to a stable postfusion conformation. Leveraging prior structure-based designs for human cytomegalovirus (HCMV) gB, we engineered amino acid substitutions in HSV-2 gB to stabilize its prefusion conformation. Cryo-EM of the engineered construct revealed a prefusion conformation and non-native dimers of gB trimers. Introduction of N-linked glycosylation sites resulted in the gB-G3 variant, which exhibited improved expression and reduced dimerization. Cryo-EM of gB-G3 bound to neutralizing antibodies yielded a 2.8 [A] resolution structure of the stabilized prefusion conformation in a closed state, which differs from the open states observed in recently published HSV gB structures. Both prefusion and postfusion gB variants were evaluated for immunogenicity in mice, delivered either as a protein subunit or mRNA vaccine. Each gB conformation elicited robust humoral and cellular responses. However, prefusion stabilization of gB did not improve neutralizing antibody titers relative to the postfusion construct, consistent with prior observations for HCMV gB. Collectively, these findings reveal insights into prefusion gB conformational dynamics, provide stabilized reagents for studying gB-directed immune responses and inform HSV-2 vaccine design.

microbiology↗

Epigenetic Programming of Macrophage Phenotypes by STING-IRF3 Drives Inflammation in Ascending Thoracic Aortic Dissection

BackgroundAscending thoracic aortic dissection (ATAD) is characterized by extensive macrophage (M{Phi}) accumulation and profound inflammation; however, the mechanisms sustaining pro-inflammatory M{Phi} activation remain incompletely defined. Emerging evidence indicates that epigenetically generated immune memory drives innate immune cells toward persistent inflammatory states. In this study, we investigated whether epigenetic reprogramming governs M{Phi} phenotypic fate and contributes to ATAD pathogenesis. MethodsWe performed single-cell RNA sequencing of human ascending aortic tissues from controls, patients with ascending thoracic aortic aneurysm (ATAA), and patients with acute ascending thoracic aortic dissection (ATAD). We also performed integrated single-cell RNA sequencing, single-cell ATAC sequencing, and spatial transcriptomics in an angiotensin II (Ang II)-infused mouse model. The role of the STING-IRF3 signaling axis in M{Phi} epigenetic programming was examined using M{Phi}-Sting -/- and M{Phi}-Irf3-/- mice. ResultsIn human and mouse aortic tissues, we identified multiple functional M{Phi} populations including pro-inflammatory, phagocytic/anti-inflammatory, proliferative, and reparative/healing M{Phi}s. Aortic M{Phi}s in both sporadic ATAD patients and Ang II-induced ATAD mice exhibited a pronounced pro-inflammatory bias with enhanced differentiation toward pro-inflammatory M{Phi}s and impaired differentiation toward phagocytic/anti-inflammatory states. Pro-inflammatory M{Phi}s were particularly abundant in dissection sites, whereas phagocytic M{Phi}s were enriched in discrete adventitial niches. Origin analyses revealed a substantial increase in CCR2 recruited M{Phi}s within the aortic wall, which preferentially differentiated into pro-inflammatory M{Phi}s. In contrast, LYVE1 resident M{Phi}s-- predominantly biased toward phagocytic phenotypes--were markedly depleted in ATAD. Single-cell ATAC sequencing identified coordinated chromatin remodeling with increased accessibility at pro-inflammatory gene loci and decreased accessibility at phagocytic gene loci. Among candidate transcriptional regulators identified, IRF family TFs, including IRF3 emerged as unique factors capable of simultaneously promoting pro-inflammatory gene programs while suppressing phagocytic gene expression. Mechanistically, STING-IRF3 signaling orchestrates this biased transcriptional state, likely through coordinated BRG1-dependent chromatin opening at pro-inflammatory gene loci and chromatin closing at phagocytic/anti-inflammatory gene loci. M{Phi} specific Sting -/- and Irf3-/- mice exhibited attenuated inflammatory reprogramming and reduced aortic destruction and dissection. ConclusionsThese findings identify STING-IRF3-mediated epigenetic programming of M{Phi}s as a fundamental mechanism driving aortic inflammation and ATAD development. Targeting M{Phi} epigenetic programming may represent a promising therapeutic strategy to prevent aortic dissection. Graphic Abstract O_FIG O_LINKSMALLFIG WIDTH=189 HEIGHT=200 SRC="FIGDIR/small/701198v1_ufig1.gif" ALT="Figure 1"> View larger version (29K): org.highwire.dtl.DTLVardef@c97bcdorg.highwire.dtl.DTLVardef@1df0ca8org.highwire.dtl.DTLVardef@b7fd04org.highwire.dtl.DTLVardef@1443e16_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

RingNet: An Interactive Platform for Multi-Modal Data Visualization in Networks

The exponential growth of data in biomedicine has created an urgent need for intuitive visualization tools. These tools should effectively represent complex biological networks and remain accessible to domain experts without extensive computational training. Current network visualization approaches often require specialized programming skills and/or cannot handle the scale and complexity of modern biomedical datasets, which creates significant barriers to biological discovery. We develop RingNet, a web-based interactive visualization tool that integrates computational efficiency with flexible, user-driven exploration. This tool addresses the communitys need to visualize multi-modal datasets within a single, compact network representation, as well as identify patterns of interest in complex data. RingNet uses an R backend for network computation and coordinate optimization. This generates JSON data structures that feed into a JavaScript and HTML frontend, which provides real-time, interactive visualization functions. It offers dynamic layout adjustments, node and edge filtering, and customizable color schemes for representing data. It can export reproducible, publication-ready figures in SVG and PNG formats. In our case studies, we use RingNet to visualize breast cancer patients omics profiles in a gene regulatory network and a cell-to-cell communication network in atopic dermatitis. This demonstrates RingNets ability to reveal biological relationships across multiple data modalities. HighlightsO_LIRingNet enables intuitive, interactive visualization of multi-modal networks without requiring advanced computational or programming expertise. C_LIO_LIRingNet has two functions: one to identify patterns in complex data at the node level, and the other to identify samples with homogeneous and heterogeneous profiles within network nodes. C_LIO_LIRingNet integrates efficient backend computation with real-time, flexible frontend exploration in a single, web-based framework. C_LIO_LIRingNet reveals cross-modal biological relationships and produces reproducible, publication-ready figures. C_LI Graphic abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=75 SRC="FIGDIR/small/700593v4_ufig1.gif" ALT="Figure 1"> View larger version (24K): org.highwire.dtl.DTLVardef@7c79f2org.highwire.dtl.DTLVardef@2a0c73org.highwire.dtl.DTLVardef@97845eorg.highwire.dtl.DTLVardef@1735352_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioinformatics↗

Asarinin Inhibits RANKL-Induced Osteoclast Differentiation by Targeting the p38/ERK-c-Fos-NFATc1 Axis

Excessive osteoclast formation is a key contributor to pathological bone loss in disorders such as osteoporosis and rheumatoid arthritis. Asarinin, a natural lignan, has not previously been examined in the context of osteoclast differentiation. Here, we investigated the anti-osteoclastogenic effects of asarinin using RANKL-stimulated RAW264.7 cells. Asarinin significantly suppressed TRAP-positive multinucleated osteoclast formation under the tested conditions. Mechanistically, asarinin selectively inhibited RANKL-induced phosphorylation of p38 and ERK MAPKs, leading to reduced c-Fos expression and inhibition of NFATc1 nuclear translocation. In addition, asarinin disrupted actin ring formation in mature osteoclasts. Collectively, these findings identify asarinin as a pathway-selective inhibitor of osteoclast differentiation, targeting the p38/ERK-c-Fos-NFATc1 axis while sparing parallel signaling pathways.

pharmacology and toxicology↗

Bayesian rhythmic model for jointly detecting circadian biomarkers and predicting molecular circadian time in human post-mortem brain transcriptome

Transcriptomic circadian analysis of human post-mortem brain provides a unique opportunity to characterize in vivo molecular circadian rhythms across brain regions implicated in aging and psychiatric disorders. A primary goal in such analyses is the detection of circadian biomarkers. However, this task is complicated by the frequent mismatch between a subjects recorded circadian clock time and their true molecular circadian time -- arising from observational or recording errors, as well as intrinsic biological variability. Existing methods typically address either biomarker detection or circadian time prediction in isolation. Because errors in one task can degrade performance in the other, the lack of a unified approach remains a key limitation. We propose BayCT -- a Bayesian model for simultaneous circadian marker detection and molecular circadian time estimation. The model extends naturally to repeated measurements from multiple brain regions or organs. For circular data, we employ a von Mises prior distribution, with slice sampling and reversible-jump Markov chain Monte Carlo (MCMC) for Bayesian inference. Through extensive simulations and applications to transcriptomic data from three human brain regions and from 12 mouse organs, BayCT demonstrates superior performance in both biomarker detection and circadian time estimation. Furthermore, we highlight the advantages of integrating data across brain regions, achieving substantial improvements in both tasks.

bioinformatics↗

An anatomical hotspot for striatal dopamine-acetylcholine interactions during reward and movement

Dopamine (DA) and acetylcholine (ACh) are key neuromodulators that regulate striatal circuits underlying movement and reinforcement learning. Evidence suggests that DA and ACh systems interact, but where and how interactions are expressed across striatal regions in behaviorally relevant release dynamics remains unknown. We applied micro-fiber arrays to simultaneously measure striatum-wide DA and ACh in behaving mice, revealing an anatomical organization in which DA-ACh anti-correlations were concentrated in a hotspot in the anterior dorsolateral striatum (aDLS). Anti-correlations resulted from temporally coincident pairs of spontaneous and event-locked transient peak and dip events occurring in a DA[->]ACh sequence. The aDLS localized hotspot was consistently expressed within distinct signals associated with unpredicted rewards, learned and extinguished Pavlovian cues, and locomotion initiation and invigoration phases, for which we revealed novel, opposing DA-ACh dynamics. Optogenetic activation of DA neurons selectively suppressed spontaneous ACh release within the aDLS hotspot, and ex vivo recordings revealed enhanced D2-mediated ACh inhibition in aDLS relative to ventral regions, suggesting a mechanistic basis for this spatial specificity. These findings demonstrate that DA-ACh interactions during behavior are spatially organized, rather than uniformly conserved, and shape behaviorally relevant dynamics to regulate region-specific functions in learning and movement control.

neuroscience↗

Methyl Carnosate, a Carnosic Acid Derivative, Attenuates Osteoclastogenesis via Modulation of RANKL-Induced NF-κB Activity

Excessive osteoclast activity underlies bone-destructive diseases including osteoporosis and rheumatoid arthritis. RANKL-induced NF-{kappa}B signaling represents a critical pathway driving osteoclastogenesis. Here, we report that methyl carnosate, a naturally occurring diterpene from rosemary, inhibits RANKL-induced osteoclastogenesis with an IC50 of 1.2 M and displays greater potency than its parent compound, carnosic acid. Promoter-reporter analysis further indicates attenuation of RANKL-induced NF-{kappa}B activity. These findings identify methyl carnosate as a potential lead compound for the development of bone-protective therapeutics.

pharmacology and toxicology↗

Universal nucleic acid preservation in biological fluids with boron clusters

Nucleic acid preservation remains a critical bottleneck for diagnostics and therapeutics, with small molecule inhibitors such as EDTA showing limited spectrum against diverse nucleases, while protein-based alternatives requiring costly cold-chain storage. Here, we report dodecaborate cluster [B12H12]2- as a novel class of pan-nuclease inhibitor with a fundamentally different mechanism--preventing protein-nucleic acid interactions rather than targeting cofactor dependencies. [B12H12]2- inhibited all six DNases and ten RNases tested, making it the broadest spectrum nuclease inhibitor known. Remarkably, its inhibition is reversible via {gamma}-cyclodextrin complexation. We demonstrate that [B12H12]2- preserved a physiological range of DNA for 14 days and that of RNA for 3-7 days at room temperature in human plasma and urine, achieving up to 323,972-fold better RNA retention than controls. A newly developed blood collection tube using [B12H12]2- enables whole-blood circulating cell-free RNA sequencing after 7 days of room-temperature storage, with preserved transcript integrity. Mechanistic studies suggest [B12H12]2- binds to nuclease active sites and creates electrostatic barriers that prevent substrate binding. This chemically stable, indefinitely shelf-stable inhibitor enables cold-chain-free biological sample transport, potentially transforming accessibility of nucleic acid-based diagnostics worldwide. Graphical abstract

bioengineering↗

8-Epixanthatin Suppresses RANKL-Induced Osteoclast Differentiation via Inhibition of NF-κB and MAPK Signaling

Osteoclast hyperactivity represents a central mechanism in pathological bone destruction, underscoring the importance of discovering novel anti-resorptive compounds. In this study, we present early-stage evidence that 8-Epixanthatin can inhibit osteoclast differentiation induced by RANKL. 8-Epixanthatin exhibited no significant cytotoxicity at the concentrations used for osteoclast differentiation studies. The compound showed concentration-dependent reductions in TRAP-positive multinucleated osteoclasts, with an IC50 value of 2.3 M. Our mechanistic investigations revealed that 8-Epixanthatin interferes with RANKL-activated signaling networks, particularly NF-{kappa}B and MAPK cascades. Collectively, these observations identify 8-Epixanthatin as a promising lead structure for anti-osteoclast drug discovery.

pharmacology and toxicology↗

Targeting CHI3L1 in Alzheimers Disease: Optimization of G721-0282 and Functional Evaluation in Astrocyte Models

Alzheimers disease (AD) involves astrocytic dysfunction characterized by impaired lysosomal activity, defective amyloid clearance, and neuroinflammation, processes strongly regulated by the inflammatory effector CHI3L1. G721-0282, a reported CHI3L1-binding small molecule with demonstrated modulation of downstream signaling pathways including MAPK and STAT3, provides a validated chemical starting point for targeting CHI3L1-driven astrocytic pathology in AD, but exhibits suboptimal potency and drug-like properties that limit its translational potential. We therefore performed a virtual screening of commercially available analogues of G721-0282 to enable structure-guided optimization, generating a detailed structure-activity map and prioritizing 24 derivatives. Biophysical analyses identified compound G721-0377 as the most promising candidate, with optimized substitutions improving CHI3L1 binding affinity. Compound G721-0377 also exhibited favorable pharmacokinetic properties, including improved solubility, balanced permeability, reduced microsomal clearance, and an enhanced cardiac safety margin. Functionally, G721-0377 uniquely reversed CHI3L1-induced astrocytic dysfunction, restoring amyloid uptake, lysosomal proteolysis and acidification, suppressing CHI3L1 and IL-6 secretion, and inhibiting NF-{kappa}B activation to levels comparable to a neutralizing anti-CHI3L1 antibody. In contrast, compounds G721-0179 and G857-1069 showed minimal activity. Collectively, these findings establish G721-0377 as a next-generation CHI3L1 inhibitor with improved affinity, safety, and robust functional efficacy, supporting its further development as a disease-modifying therapeutic for AD.

pharmacology and toxicology↗

Tumor cell death by ferroptosis contributes to an immunosuppressive tumor microenvironment in syngeneic murine models of cancer

Pancreatic ductal adenocarcinoma (PDAC) is characterized by profound metabolic rewiring and a strongly immunosuppressive tumor microenvironment, both of which contribute to poor therapeutic responses. Immunogenic cell death (ICD) represents a potential strategy to overcome immune suppression by coupling tumor cell death to anti-tumor immune activation. Here, we investigated whether targeting amino acid metabolism in PDAC can induce ICD and promote tumor immunity. Through a focused metabolic screen in a panel of syngeneic mouse cancer cell lines, we identified cysteine restriction as a robust inducer of multiple damage-associated molecular patterns (DAMPs) in vitro, hallmark features of ICD. In addition to driving DAMPs, cystine-deprived tumor cells also promoted dendritic cell phagocytosis, maturation, and proinflammatory cytokine production in vitro. Because cysteine deprivation is a known trigger of ferroptosis, we further demonstrated that pharmacologic inhibition of glutathione peroxidase 4 (GPX4) similarly elicited ICD-associated features, which were reversible by the ferroptosis inhibitor Ferrostatin-1. To define additional immune-modulatory signals associated with ferroptosis, we performed metabolomic and lipidomic profiling of cells undergoing, but not yet committed to, ferroptotic death. These analyses revealed selective release of immunosuppressive metabolites and oxidized phospholipids. Consistent with this, conditioned media from ferroptotic cells impaired CD8 T cell proliferation and cytotoxicity in vitro. Thus, together our results indicated that the induction of ferroptotic immunogenic cell death led to the release of both pro- and anti-inflammatory signals. Subsequent analysis in vivo revealed that ferroptotic tumor cells predominantly contributed to a tumor-protective environment. In particular, tumors inoculated with ferroptotic cells were enriched with immunosuppressive myeloid cells and exhibited reduced populations of tumor-infiltrating CD8+ T cells. Further investigation using immune compromised mice suggested that ferroptotic cells may suppress both adaptive and innate immune responses. Collectively, these results underscore the complex and highly context-dependent effects of ferroptosis on tumor immunity, highlighting the critical importance of in vivo models to determine true immunogenic potential within the tumor microenvironment.

cancer biology↗

MOV10 inhibits SADS-CoV replication by enhancing TRIM24-mediated K63-linked TRAF3 ubiquitination and this inhibition is antagonized by viral N protein

The global outbreak of SARS-CoV-2 has resulted in a renewed focus on coronaviruses with the potential for cross-species transmission and mutation risks. In particular, swine acute diarrhea syndrome coronavirus (SADS-CoV), potentially originating from intermediate horseshoe bat (Rhinolophus affinis), is a novel coronavirus that causes acute diarrhea, vomiting, and high mortality in suckling piglets. Innate immunity plays a crucial role in defending the host against invading pathogens. Previous studies have identified several host factors that inhibit SADS-CoV replication through innate immunity; however, research on SADS-CoV remains insufficient compared to that on other coronaviruses. In this study, the host factor Moloney leukemia virus 10 protein (MOV10) inhibited SADS-CoV replication by promoting interferon (IFN) production. Mechanistically, MOV10 exerted its antiviral effect primarily through its N-terminal domain, which regulated the TNF receptor-associated factor 3 (TRAF3)-mediated innate immune pathway. Specifically, we reveal that MOV10 enhanced tripartite motif-containing 24 (TRIM24)-mediated K63-linked ubiquitination of TRAF3, thereby promoting IFN production and inhibiting SADS-CoV replication. Furthermore, we identified the strategies by which SADS-CoV evaded innate immunity. The viral N protein inhibited the antiviral effect of MOV10 by disrupting interaction between MOV10 and TRAF3, and by promoting K48-linked polyubiquitination of TRAF3, leading to TRAF3 degradation via the ubiquitin-proteasome pathway. Collectively, our findings reveal the role of MOV10 in antiviral immunity and how SADS-CoV evades host immune defense.

molecular biology↗