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Lu, X.

Publications and source records attributed to Lu, X..

At least 19 recordsLinked to original sources

Integrative multi-omics decoding of the host response to Klebsiella pneumoniae infection reveals an itaconate-centred metabolic-immune axis and a spatially organised inflammatory programme

Background: Klebsiella pneumoniae (Kp) is a leading cause of hospital and community acquired pneumonia and bacteraemia, and hypervirulent and carbapenem resistant lineages continue to expand worldwide. Although individual omics layers of Kp infection have been profiled, the host-level molecular logic that connects transcriptional, cellular, metabolic and spatial programmes has not been systematically integrated. Methods: We curated 16 public datasets spanning four modalities-bulk and dual host pathogen RNA-seq (six datasets; 118 libraries), single-cell RNA-seq (four datasets; {approx}164,000 cells), untargeted/targeted metabolomics (four datasets; 1,842 molecular features) and Visium spatial transcriptomics (two datasets; {approx}11,400 spots) covering murine lung infection models, hypervirulent and classical Kp strains, carbapenem-resistant isolates and human clinical specimens. Datasets were harmonised through a standardised pipeline (Salmon/DESeq2; Scanpy/Harmony; MetaboAnalyst; RCTD/spacexr), and integrated by WGCNA, GSVA, CellChat, Monocle3, SCENIC, joint-pathway analysis, RCTD deconvolution, and machine-learning feature selection (LASSO, random forest, SVM-RFE, XGBoost) with 1,000x bootstrap internal validation and independent external validation. Results: Kp infection evoked a coherent 920 gene neutrophil inflammatory response ({approx}520 up-/{approx}400 down-regulated genes) dominated by IL-17/TNF/NF-{kappa}B signalling, neutrophil degranulation, HIF-1-linked glycolysis and itaconate biosynthesis. A turquoise co-expression module (r = 0.86 with infection status) yielded a ten-gene hub signature (IRG1, S100A9, IL1B, CXCL2, SLC7A11, HMOX1, PTGS2, NFKBIA, LST1, FCGR3B). Single-cell profiling resolved twelve major lung lineages and eleven myeloid substates, tracing a Monocle3 trajectory from Cxcr2hi inflammatory neutrophils through an Irg1/Slc7a11hi oxidative phase into Cxcr4hi/Trem2hi suppressive states; CellChat identified S100A8/A9-TLR4 and CXCL2-CXCR2 as the most amplified axes (8.5x and 4.2x). Metabolomics revealed 30-fold pulmonary itaconate accumulation together with succinate and lactate elevation, glucose/glutamine depletion and glutathione collapse, and joint-pathway analysis positioned the TCA-cycle itaconate and ferroptosis modules as the strongest convergent perturbations. Spatial transcriptomics mapped these programmes onto five anatomical niches, with IRG1 expression peaking in the infection core (58% neutrophil content) and declining radially. A ten-gene host-response classification model reached AUC=0.958 in discovery, 0.937 in internal validation and 0.884-0.912 in two independent external cohorts (Brier score 0.071). Conclusions: By vertically integrating public multi-omics data, we define an itaconate-centred metabolic-immune axis that couples inflammatory myeloid expansion to spatially segregated metabolic niches, and we deliver a validated host-side molecular signature that discriminates Kp infection from non-infected states.

microbiology↗

Retinal Phd2 ablation partially rescues Crb1Crb2-associated Leber congenital amaurosis and alters metabolic signaling

Leber congenital amaurosis (LCA) is a severe early-onset retinal dystrophy caused by pathogenic variants in several genes, including CRB1. CRB1-associated LCA is characterized by disrupted retinal polarity, lamination, and photoreceptor organization, with no restorative treatment. We investigated whether retinal deletion of Phd2 (Egln1), encoding prolyl hydroxylase domain protein 2 (PHD2), could provide mutation-independent neuroprotection in a severe developmental model of CRB1-associated LCA. Using conditional Crb1/Crb2-deficient mice, we additionally deleted Phd2 throughout the neural retina and assessed retinal function, structure, visually guided behavior, and glycolysis-associated gene and protein expression at one and two months. Compared with Crb1/Crb2-deficient mice, additional Phd2 deletion partially improved scotopic responses and significantly increased the optomotor spatial-frequency threshold, whereas b-wave and cone-mediated responses remained impaired. Phd2Crb1Crb2-deficient retinas displayed more organized photoreceptor rosettes containing rod- and cone-marker-positive cells, in contrast to the diffuse outer-retinal disorganization and nuclear-layer amalgamation observed in Crb1/Crb2-deficient retinas. Polarity- and synapse-associated proteins showed improved local compartmentalization within these structures. Metabolic responses were temporally selective: Glut1 and Vegfa transcript levels increased at one month, whereas GLUT1 and LDHA protein levels increased at two months; Pdk1 transcript levels decreased at 2M, whereas PDK1 protein abundance remained unchanged. Although Phd2 deletion did not correct the underlying Crumbs-complex defect or normalize retinal lamination, and elevated Vegfa coincided with persistent vascular abnormalities, these findings demonstrate that retinal Phd2 deletion partially modifies the structural and functional consequences of severe Crb1/Crb2 deficiency and supports further investigation of PHD2-associated metabolic signaling as a potential disease-modifying target for severe CRB1-associated retinal degeneration.

neuroscience↗

Stereociliary localization and function of the tip-link protein PCDH15-CD2 are regulated by the PDZ-scaffold NHERF-1

Sensory hair cells in the inner ear convert mechanical sound deflections into electrical signals via the stereociliary hair bundle on their apical surface. Proper bundle function requires that structural, adhesion, and motor proteins be delivered to specific stereocilia sub-compartments and maintained at precise levels throughout life, yet the underlying mechanisms remain poorly understood. Here we investigated how spatiotemporal localization of Protocadherin-15 (PCDH15), a component of kinociliary links, transient lateral links, and tip links, is regulated in mouse auditory hair cells. Using biochemical assays in vitro, we identified the PDZ-domain scaffolds NHERF-1/2 as direct binding partners of CD2, a PCDH15 isoform essential for hearing. We mapped the interaction to NHERF-1's PDZ1 domain and CD2's PDZ-binding motif (PBM), and showed that this binding is regulated by phosphorylation of the CD2 PBM. Using Nherf1 knockout and Pcdh15-CD2 knock-in mice defective in this interaction, we found CD2-NHERF-1 binding is required for proper CD2 levels and localization in the developing hair bundle. Loss of this interaction largely spared early bundle morphogenesis and MET function but caused high-frequency hearing loss and degeneration of the shortest stereociliary row in adult mice. Together, these findings define an important regulatory mechanism with therapeutic relevance for hair bundle repair.

cell biology↗

Fine-tuning an intracellular allosteric pocket programs GPCR signaling bias

Biased signaling of G protein-coupled receptors (GPCRs) offers a route for precise therapeutics with fewer adverse effects. Intracellular allosteric ligands can impose such bias, yet how subtle chemical changes within these pockets reshape receptor-transducer coupling and downstream signaling remains unclear. Here, we systematically fine-tuned the intracellular allosteric pocket of neurotensin receptor 1 (NTSR1) through chemical modification of the {beta}-arrestin-biased ligand SBI-553. Minor changes to the ligand scaffold altered transducer-coupling preferences, generating distinct profiles of G-protein and {beta}-arrestin signaling. Cryo-electron microscopy structures of NTSR1-{beta}-arrestin2 complexes bound to designed allosteric probes revealed ligand-dependent remodeling of the intracellular cavity that reshapes the receptor-effector interface. Alanine scanning identified transducer-sensitive residues within and beyond the immediate ligand-contact region. In mice, SBI-553 and N065 produced distinct physiological profiles, with N065 improving survival in a lethal endotoxemia model. Finally, phosphoproteomic profiling revealed partially overlapping but distinct downstream signaling profiles among the three modulators. Together, these findings establish the intracellular allosteric pocket as a tunable determinant of transducer coupling and show that closely related modulators can generate distinct signaling and physiological profiles.

pharmacology and toxicology↗

An OmpX mRNA-LNP vaccine induces protective humoral and cellular immunity against Klebsiella pneumoniae in a C57BL/6 mouse model

Klebsiella pneumoniae (KP) poses a significant threat to global public health, and effective preventive measures are urgently needed. The widespread antibiotic resistance of KP underscores the critical need for vaccine-based strategies. Although numerous vaccine candidates against KP have been investigated, none has yet been licensed. mRNA-LNP vaccines against KP have only recently begun to be explored, and their ability to deliver conserved outer membrane protein antigens remains largely untested. In this study, we constructed an mRNA vaccine encoding the highly conserved outer membrane protein X (OmpX) of KP-the first mRNA-LNP vaccine targeting this antigen-and evaluated its immunogenicity and protective efficacy in mice. Immunoinformatics analyses predicted concordance between the in silico and in vivo outcomes: bioinformatics tools were used to evaluate the antigenicity, immunogenicity, physicochemical parameters, and secondary and tertiary structures of OmpX, and the C-ImmSim server was used to simulate the vaccine-elicited immune responses. We then performed mouse immunization and challenge experiments to characterize the humoral and cellular immune responses induced by the OmpX vaccine. The mRNA vaccine was immunogenic in mice, eliciting high titers of OmpX-specific antibodies. OmpX-Fc mRNA-LNPs also induced robust cell-mediated immunity, with significantly elevated IFN-{gamma} and IL-4 levels indicative of combined Th1/Th2 cellular responses. Serum from OmpX-immunized mice promoted significantly greater complement-mediated KP cell lysis than serum from the alum or luciferase mRNA-LNP control groups. Notably, OmpX-Fc mRNA-LNP immunization conferred complete protection against lethal KP challenge, with 100% survival and a significant reduction in visceral bacterial burden. These data establish a promising mRNA vaccine strategy for inducing broad immune responses and promoting serotype-independent immunity against KP.

microbiology↗

Integrative reanalysis of public intracellular and vaccine-challenge transcriptomes, informed by single-cell and metabolomic atlases, refines antigen prioritisation for next-generation veterinary Brucella vaccines

Brucellosis is the most widespread bacterial zoonosis and a leading cause of abortion and infertility in cattle, sheep, goats and pigs. The live vaccines licensed for livestock (B. abortus S19 and RB51, B. melitensis Rev.1) give incomplete protection, retain residual virulence and induce antibodies that are indistinguishable from those of field infection, and no human vaccine is licensed. Antigen discovery for safer subunit and mRNA alternatives has proceeded one candidate at a time, so it remains unclear which immunogenic proteins are abundant in the intracellular niche that protective immunity must recognise. We reanalysed four public data layers: dual RNA-sequencing of intracellular B. abortus and infected murine macrophages (GSE100914), splenic transcriptomes from vaccinated and challenged mice (GSE254248), and single-cell (PRJCA054635) and metabolomic (ST003696, ST003692) atlases. Intracellular residence induced 704 genes and repressed 249, enriching translation functions 2.9-fold. Omp28/BP26 was the second most abundant intracellular transcript (35,652 TPM; log2FC 4.25), whereas the lipoproteins omp16, omp10 and omp19 were 116-637-fold less abundant. Vaccination left a germinal-centre and TCF1+ memory imprint rather than an effector-cytokine signature. A composite score combining abundance, induction and surface exposure reorders the candidate panel, placing Omp28/BP26 and omp2b above current candidates and defining concrete priorities for veterinary vaccine development.

immunology↗

Establishment and characterization of LNCaP-TR-BoM, a bone metastasis-derived prostate cancer cell line with an intermediate AR-attenuated phenotype

Background. Progression of prostate cancer under androgen receptor (AR) pathway-targeted therapy spans a phenotypic spectrum, from tumors that sustain AR pathway output to tumors that become independent of AR signaling. Experimental models that occupy the intermediate portion of this spectrum, in which AR is still expressed but pathway output is reduced, are comparatively scarce. Methods. LNCaP cells expressing a triple-modality reporter (LNCaP-TR) were injected into nude mice by the intracardiac route, and a bone lesion that arose in the middle spine of one animal was recovered and propagated as LNCaP-TR-BoM. The subline and its parental line were compared by two-dimensional and three-dimensional culture assays, RNA-seq, qRT-PCR, and immunoblotting. AR pathway output was assessed using KLK3 expression under AR antagonist treatment. Public prostate cancer datasets provided clinical context. A CRISPR-Cas9 EPHA3-edited derivative was evaluated in aggregation and spheroid assays. Results. Relative to parental LNCaP-TR, LNCaP-TR-BoM formed more numerous and larger cell aggregates in monolayer culture and larger, less circular spheroids in both suspension and Matrigel three-dimensional culture. AR mRNA was modestly reduced and AR protein remained readily detectable, whereas KLK3 mRNA and protein were reduced disproportionately more than those of AR. Residual KLK3 expression remained suppressible by AR inhibitors enzalutamide and darolutamide. Transcriptome-based pseudotime placed LNCaP-TR-BoM between the parental line and the androgen-refractory LNCaP-RF variant. Subsequent differential gene expression (DGE) and pathway enrichment analysis revealed that LNCaP-TR-BoM exhibits transcriptomic rewiring concordant with that of clinical mCRPC, thus evidencing LNCaP-TR-BoM as a potentially clinically relevant model cell line. Finally, EPHA3 showed the largest fold change among the most significant differentially expressed genes in LNCaP-TR-BoM compared with the parental line. Therefore, EPHA3 was explored to demonstrate the utility of the LNCaP-TR-BoM cell line as a discovery system for genes that potentially drive the malignancy of bone-metastatic prostate cancer at the intermediate AR-attenuated progression stage. An EPHA3-silenced derivative of LNCaP-TR-BoM lacking detectable EPHA3 protein formed smaller aggregates and smaller, more circular spheroids, suggesting EPHA3 may play a role in driving the malignancy of AR-intermediate bone-metastatic prostate cancer. This finding provides support for the potential utility of the LNCaP-TR-BoM cell line as a discovery system for genes relevant to driving AR-intermediate bone-metastatic prostate cancer. Conclusions. LNCaP-TR-BoM is a bone lesion-derived prostate cancer cell line in which AR expression is retained but AR pathway output is attenuated, accompanied by an mCRPC-concordant transcriptomic shift and altered multicellular organization. It provides a paired discovery system for candidate genes such as EPHA3.

cancer biology↗

The annexin A1 mimetic peptide Ac2-26 promotes inflammation-resolution and stimulates skeletal muscle regeneration in the mdx mouse model of Duchenne muscular dystrophy

Duchenne muscular dystrophy (DMD) is an X-linked disorder mainly affecting young boys characterized by repeated cycles of myofiber injury/regeneration and chronic muscle inflammation. Although glucocorticoids can slow disease progression, their potential long-term adverse effects highlight the need for new steroid-sparing therapies for DMD. Annexin A1 (ANXA1) is a glucocorticoid-induced pro-resolving protein that signals primarily through formyl peptide receptor 2 (FPR2). We investigated whether the ANXA1 mimetic peptide Ac2-26 could reduce inflammation, stimulate tissue regeneration, and improve skeletal muscle function in muscular dystrophy. 3-week-old dystrophin-deficient male mdx mice were randomized to receive daily intraperitoneal injections of vehicle control, deflazacort (1 mg/kg/day), or Ac2-26 (1 mg/kg/day) for a duration of 5-weeks. Body composition, skeletal muscle mass, contractile function, and tissue histopathology/immune-cell infiltration were assessed at 8-weeks of age. Direct effects on myogenesis were also examined in vitro using primary D2-mdx myoblasts. ANXA1 was expressed predominantly by myeloid cells rather than resident dystrophic muscle cells. Both deflazacort and Ac2-26 markedly reduced intramuscular inflammation and increased myofiber size. However, Ac2-26 produced broader anabolic and functional benefits, increasing body-weight gain, lean body mass, hindlimb muscle weights, and absolute contractile force. Ac2-26 treatment also directly promoted myogenesis of dystrophic myoblasts in vitro, while pharmacological FPR2 blockade impaired myotube development. Overall, Ac2-26 mimicked the anti-inflammatory effects of deflazacort while providing superior benefits for body weight and composition, skeletal muscle growth, myofiber regeneration, and absolute muscle strength. These findings support therapeutic targeting of the ANXA1-FPR2 axis as a potential safe and effective steroid-sparing immunomodulatory strategy for DMD.

cell biology↗

Cell-of-origin shapes tumor subtype in BRCA1-associated triple-negative breast cancer

Pathogenic germline BRCA1 variants greatly increase lifetime breast cancer risk, with no targeted prevention. Accrual of mutations following DNA repair errors in luminal progenitors is considered the chief mechanism of triple-negative breast cancer (TNBC) initiation, which cannot explain the organ specificity nor the phenotypic spectrum of the disease. Here we show that TNBC also originates in basal-myoepithelial cells, and that the cell of origin shapes TNBC subtype through aberrant epithelial differentiation, likely due to pleiotropic role of BRCA1 in regulating hormone signaling. Single-cell RNA sequencing of 67,001 cells from Wap-Cre Brca1/p53 mice and reanalysis of published Blg-Cre data show that aberrant basal-myoepithelial differentiation (Wap-Cre) generates the mesenchymal subtype (TNBC-M) and aberrant luminal differentiation (Blg-Cre) the basal-like subtype (TNBC-BL1). We also show that both subtypes occur at comparable frequency in BRCA1 carriers. Aberrant basal-myoepithelial differentiation precedes tumor formation, and only tumors derived from transplanted basal cells reproduce the basal-containing phenotype of spontaneous tumors. Comparison with a developmental atlas identifies de-differentiation of myoepithelial cells into basal cells lacking myoepithelial markers, a fetal state, whereas experimental metastases shift toward luminal states while retaining a TNBC-M-like transcriptional program. These findings support the inclusion of basal-myoepithelial and luminal cells in targeted prevention strategies for BRCA1 carriers, and adoption of TNBC subtyping for patient stratification and improving outcomes.

cancer biology↗

USH2A High-Capacity Adenoviral Vector Restores usherin, whirlin, and ADGRV1 in Photoreceptor Cells of Retinal Organoids

Development of gene therapies for USH2A-associated diseases has been limited by the large size of the USH2A coding sequence, which exceeds the packaging capacity of adeno-associated viral vectors. Here, we evaluated high-capacity adenoviral vectors (HC-AdVs) as vehicles for a mutation-independent USH2A gene supplementation strategy in USH2A human retinal organoids. First, we generated human induced pluripotent stem cell (hiPSC) lines carrying a nonsense mutation in USH2A exon-61 (61KO). Similarly to our previously established exon-13 knockout model (13KO), 61KO hiPSC-derived retinal organoids showed reduced levels of usherin and its interacting proteins, adhesion G protein-coupled receptor V1 (ADGRV1), and whirlin, at the photoreceptor connecting cilium. Delivery of a HC-AdV5 encoding full-length USH2A under the control of the photoreceptor-specific human rhodopsin kinase (hGRK1) promoter restored usherin expression and promoted re-localization of ADGRV1 and whirlin to their physiological sites at the connecting cilium in 13KO and 61KO photoreceptors. Unexpectedly, usherin expression was also observed within mutant Muller glial cells. These findings provide proof-of-concept that HC-AdV5-mediated delivery of full-length USH2A can successfully promote the rescue of usherin and relocate its interacting partners in USH2A-defective retinal organoids, demonstrating its potential as a variant-independent therapeutic approach for inherited retinal disorders caused by USH2A mutations.

neuroscience↗

Genomic splice-donor disruption rescues systemic disease in progeria

RNA splicing determines which protein isoforms a gene produces, and aberrant splice-site activation can cause severe disease. In Hutchinson-Gilford progeria syndrome, a synonymous LMNA mutation strengthens a cryptic 5' splice donor site to produce progerin, a toxic lamin A isoform driving premature cardiovascular death. Within this cryptic donor, the activating mutation lies near the canonical GT dinucleotide required for splice-site recognition. A single guide can therefore preferentially pair with the mutant sequence while positioning Cas9 cleavage at this dinucleotide. Here we show that CRISPR/Cas9-mediated disruption of this splice site suppresses progerin without requiring precise correction of the activating mutation and prolongs lifespan in progeroid mice. In patient-derived fibroblasts and induced pluripotent stem cell-derived mesenchymal stem cells, this intervention reduced progerin by 92.7-96.8% while retaining lamin A and lamin C expression. A single neonatal injection of AAV9 carrying the corresponding mouse guide increased median survival from 115 to 279 days in Cas9-expressing LmnaG609G/G609G mice. Treatment attenuated aortic, skeletal and multiorgan pathology. Treated homozygous pairs produced 52 offspring across seven litters. These findings establish pathogenic splice signals as genomic targets for sustained suppression of toxic isoforms while retaining canonical gene outputs.

cell biology↗

EDTP Loss of Function Impairs Longevity and Reproduction

This study presents a comprehensive genetic characterization of DJ694, a viable GAL4 enhancer-trap allele of the age-regulated gene EDTP. EDTP transcript levels are reduced in DJ694, and homozygous flies exhibit reduced reproduction and shortened lifespan in both sexes. The fertility and longevity phenotypes are recessive and can be fully rescued by three independent UAS-EDTP insertions. Expression of UAS-EDTP into animals with wildtype phenotypes does not affect female fertility or lifespan. DJ694 has a jumpy behaviour but it is not detected by a locomotion assay. Like its human homolog, Muscle-specific Inositol Phosphatase (MIP, also known as MTMR14), EDTP is mainly expressed in adult muscles. The structure of the muscle, myofibril, and sarcomere appears normal in homozygous DJ694. DJ694 females have morphologically normal ovaries, implicating a functional rather than structural impairment. We demonstrate that EDTP is required during both development and adulthood to support normal fertility, with expression restricted to either stage alone being insufficient. Although it has been reported that EDTP can influence the accumulation of polyglutamine aggregates, we did not find evidence in its native tissue. Ectopic expression in the eye reduces the amount of aggregates but EDTP overexpression in muscles has no detectable effect on the accumulation or toxicity of two different kinds of polyglutamine aggregates.

genetics↗

Cell-type separability predicts annotation accuracy and outweighs algorithm choice: a factorial benchmark across seven scRNA paradigms

Automated cell-type annotation is a prerequisite for most single-cell RNA-sequencing (scRNA-seq) analyses, but the rapid proliferation of methods spanning marker-based, correlation-based, classical machine-learning, deep-learning, semi-supervised, large-language-model (LLM), and transformer foundation-model paradigms has outpaced head-to-head evaluation. Existing benchmarks rely on convenience samples of real datasets in which cell count, class imbalance, cell-type number, and differential-expression strength co-vary uncontrollably, precluding causal attribution of performance to any dataset property. To resolve this, we benchmarked 63 tools across seven paradigms using a Taguchi L9(34) orthogonal array that varies four dataset properties independently, progressively reconfiguring experimental control across five phases: fully controlled simulation, within-platform and cross-platform real-data validation, database-connected and LLM-based annotation under ontology-aware scoring, and fine-tuned foundation models. Using standardized oracle inputs and Cohen's {kappa}, we found that, within the ranges tested, the major paradigms achieved comparable accuracy. Accuracy was predicted near-linearly by the separability of cell types in a shared expression embedding, measured as k-nearest-neighbor (kNN) purity, a relationship that held across sequencing platforms and in fine-tuned foundation models. We attributed the vast majority of {kappa} variance to dataset structure and only a small share to tool identity. Computational cost traded against workflow accessibility rather than accuracy: accessible correlation-based and LLM-based approaches performed competitively, while foundation models matched them only after fine-tuning. Because our oracle design isolates algorithmic capability from upstream noise, these results reframe how methods should be selected: the field's near-term gains lie in strengthening infrastructure--prioritizing tool accessibility, standardized evaluation, and robustness to pipeline variation.

bioinformatics↗

Linoleic Acid-Lyso PG Axis promoting lipid droplet-mitochondria tethering by stabilizing Noncanonically Mitochondrial PPAR β/δ to Ameliorate Microglial Dysfunction in subarachnoid hemorrhage

Background Microglial lipid handling and mitochondrial failure contribute to brain injury after subarachnoid hemorrhage (SAH), but the lipid signals coupling these processes remain unclear. We investigated whether linoleic acid (LA) restores microglial homeostasis through lysophosphatidylglycerol 16:0 (LPG[16:0]) and peroxisome proliferator-activated receptor-{delta} (PPAR{delta}). Methods Cerebrospinal fluid metabolomics included 30 patients with aneurysmal SAH and 10 control participants. Mechanisms were examined in a blood-injection mouse model and hemoglobin-exposed primary mouse microglia using targeted lipidomics, RNA sequencing, mitochondrial and phagocytosis assays, pharmacological perturbation, fractionation, coimmunoprecipitation, thermal shift analysis, and structural modeling. Behavioral outcomes were evaluated by open-field, Y-maze, and Morris water-maze testing. Results; CSF LA was higher in SAH and discriminated the groups within this cohort (area under the curve, 0.9967 [95% CI, 0.9859-1.000]; P<0.001). LA attenuated inflammatory activation and restored phagocytosis, mitochondrial membrane potential, respiration, and ATP production in hemoglobin-exposed microglia. LA restored PLA2G15-associated LPG(16:0), which phenocopied these effects. Transcriptomic and inhibitor analyses identified PPAR{delta} as a downstream effector. LPG(16:0) increased PPAR{delta} stability, and fractionation and protease protection identified a PPAR{delta} pool on the cytosolic face of the outer mitochondrial membrane. PPAR{delta} associated with PLIN2 and CPT1A, promoted lipid droplet-mitochondria apposition, and supported fatty acid oxidation. In mice, LA reduced neuroinflammatory injury and partially improved anxiety-related behavior and spatial memory.

neuroscience↗

A multi-tissue epigenomic atlas links the sheep non-coding genome to domestication and complex traits

Non-coding regulatory variation drives complex traits, domestication, and evolutionary adaptation, yet the sheep genome lacks high-resolution functional annotation. Here we present SheepEpimap, a multi-tissue regulatory atlas harmonizing 516 CUT&Tag histone modifications, ATAC-seq, and RNA-seq datasets across 43 adult tissues in sheep. We annotated 2.93 million cis-regulatory elements, yielding 557,441 enhancer-gene pairs and 145,407 variants with allele-specific effects. By training a sequence-to-function deep-learning model, we decoded the base-pair syntax of chromatin accessibility, annotated transcription factor motif instances genome-wide, and constructed 12,210 tissue-specific gene regulatory networks (GRNs). Integrating this resource with multi-tissue expression quantitative trait loci, selection sweeps, and genome-wide association studies prioritized non-coding variants driving domestication and complex traits. Finally, cross-species analysis revealed that sequence-conserved, tissue-matched enhancers were significantly enriched in the heritability of complex traits and diseases in humans. In summary, SheepEpimap (https://genome.ucsc.edu/s/mengzhu/SheepEpimap) provides an open-access foundational ecosystem for sheep functional genomics, precision breeding, and comparative biology.

genetics↗

Spatial profiling of pooled mRNA-LNP delivery in vivo with NanoSTAMP

Existing pooled lipid nanoparticle (LNP) screens lack spatial information on formulation localization, cellular uptake, and associated multicellular tissue responses. Here we introduce NanoSTAMP, a spatially resolved, pooled in vivo screening platform for barcoded LNP libraries that uses fluorescence in situ hybridization (FISH)-based barcode readout and is compatible with spatial omics. NanoSTAMP links LNP formulation to cell-type specific uptake, cargo expression, and nearby multicellular neighborhoods within intact tissue, which enables spatially-informed design of RNA delivery, establishing tissue architecture as a dimension of LNP performance.

bioengineering↗

Dystonia-associated TorsinA-ΔE mutation induces a gain-of-function interaction with XPO1 via its N-terminal hydrophobic segment

Childhood-onset DYT1 dystonia is a neurodevelopmental movement disorder caused by a three-base-pair deletion ({Delta}GAG; {Delta}E) in the TOR1A gene, which encodes TorsinA, a membrane-associated AAA+ (ATPase associated with diverse cellular activities) ATPase. However, the mechanisms by which the {Delta}E mutation causes neuronal dysfunction remain poorly understood. Using patient-derived neurons, we previously demonstrated that TorsinA-{Delta}E disrupts the nucleocytoplasmic transport (NCT) of both RNA and protein cargos. In the present study, proteomic analysis of induced human motor neurons revealed a markedly enhanced association between {Delta}E and exportin 1 (XPO1), a major nuclear export receptor. This aberrant association was enriched at the nuclear envelope and accompanied by impaired XPO1-mediated nuclear export. By integrating AlphaFold-based structural modeling with molecular, biochemical, and cellular analyses, we identified the N-terminal hydrophobic segment (HS) of TorsinA as a critical contributor to its interaction with XPO1. Deletion of the HS from {Delta}E reduced its association with XPO1, altered its nuclear envelope enrichment, and restored nuclear export. Moreover, expression of HS-derived peptides in patient-derived DYT1 neurons improved nuclear export, neurite outgrowth and branching, maturation-associated gene expression, and neuronal survival. Together, these findings identify an aberrant gain-of-function association between TorsinA-{Delta}E and XPO1 as a mechanism contributing to NCT dysfunction in DYT1 dystonia and establish the HS-dependent {Delta}E-XPO1 interaction as a potential therapeutic target.

neuroscience↗

A Time-Resolved Single-Cell Atlas Reveals Infection-Status, Age-, and Sex-Dependent Immune Responses Drive Viral Disease Severity

The majority of mortality during viral infections occurs in older males; however, underlying mechanisms by which age and sex shape antiviral immunity and pathological inflammatory responses remain incompletely understood. Here, we performed time-resolved single-cell RNA sequencing across 16 conditions spanning age, sex, and four stages of influenza infection in mice, generating a high-resolution atlas. Aged mice demonstrate delayed antiviral and inflammatory responses in multiple myeloid cells, impairing viral clearance, which delays recovery. Similarly, endothelial cells from aging mice show prolonged inflammatory and antiviral gene signatures. Altered gene signatures in immune and endothelial cells result in a shift in endothelial-immune interactions in the aged lung. Further, the infection status of the cell is a major driver of transcriptional state, with infected myeloid cells exhibiting broad upregulation of genes, including interferon-stimulated, inflammatory, complement, and oxidative stress-related genes. To assess whether these age-associated transcriptional patterns are conserved in humans, we examined BAL cells obtained from healthy individuals and COVID-19 patients, and found that immune cells from aged COVID-19 patients had elevated antiviral and pro-inflammatory gene expression compared to cells from young patients. Our analyses of sex differences identified that multiple myeloid cell types in aged male mice, but not in young male mice, show persistent inflammatory responses at later stages of infection, a likely mechanism contributing to elevated mortality in older males. These data reveal how infection status of the cell, age, and sex interact to drive persistent inflammation and impaired resolution, providing a foundational resource for designing age- and sex-specific therapeutic strategies.

immunology↗