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Biology subjects

Fang, H.

Publications and source records attributed to Fang, H..

At least 19 recordsLinked to original sources

Phosphoproteomics profiling of the monocytes uncovers the mechanosensory pathways regulating monocytes responses to pathologic level of shear stress

Background: Calcific aortic valve disease (CAVD) is the most common valvular heart disease in older adults and currently has no approved pharmacological therapy to prevent or slow disease progression. Aortic valve replacement, either surgically or by transcatheter aortic valve implantation (TAVI), therefore remains the only effective treatment for severe CAVD. Monocytes play an important role in driving inflammation and disease progression in CAVD. As the disease progresses and the aortic valve becomes increasingly stenotic, circulating monocytes passing through the narrowed valve are repeatedly exposed to pathological haemodynamic forces, including markedly elevated shear stress, before their recruitment into the valve tissue. However, how exposure to these mechanical forces reprograms circulating monocytes influences their subsequent responses within the valve remain poorly understood. Methods and Results: In this study, we used an engineered model of aortic valve stenosis combined with phosphoproteomic profiling to investigate how prolonged exposure to pathological shear stress reprograms circulating monocytes and influences their subsequent phenotype and function following recruitment into the valve matrix. We further used TAVI as a unique clinical model to determine whether restoration of physiological haemodynamics in patients with severe aortic stenosis reverses the shear-induced monocyte phenotype observed in our experimental model. We found that prolonged exposure of monocytes to pathological shear stress induced extensive remodelling of the proteomic and phosphoproteomic landscape, with enrichment of pathways associated with cellular metabolism, cytoskeletal organisation, and inflammatory signalling. Kinase activity analysis further identified increased protein kinase C (PKC) activity accompanied by suppression of AKT signalling. Consistent with these molecular changes, pathological shear stress increased actin polymerisation, mitochondrial membrane potential, intracellular calcium signalling, and PKC activity. Using a bioengineered extracellular matrix model that recapitulates the glycosaminoglycan-rich microenvironment of the stenotic aortic valve we found that prior exposure to pathological shear stress altered monocyte-to-macrophage differentiation, reducing oxidised LDL uptake and foam-cell formation while promoting co-expression of CD80 and CD163, indicative of a mixed macrophage phenotype. Finally, using a myeloid-specific Piezo1 knockout mouse model, we identified Piezo1 as a key mechanosensor linking pathological shear stress to PKC activation, mitochondrial responses, and persistent changes in monocyte phenotype following migration into the extracellular matrix. Conclusions: These findings establish a mechanistic link between abnormal valve haemodynamics, metabolic and inflammatory reprogramming of circulating monocytes, extracellular matrix remodelling, and immune dysregulation during CAVD progression, highlighting monocyte mechanotransduction and downstream PKC/Piezo1 signalling as potential therapeutic targets.

cell biology↗

Germline BRCA1 Mutation Deregulates Irradiation-Induced Cell Cycle Checkpoints in Human Mammary Luminal Progenitors

Mammary ductal tree comprises two epithelial lineages, basal and luminal, which harbour stem and progenitor cell subsets essential to breast physiology and are cancer-initiating precursors. Dysregulated cellular stress response is an early event in tumorigenesis, yet lineage-rooted study of primary breast epithelium pertinent to familial mutation carriers is limited. Here, we establish a lineage-resolved monolayer culture system that enables propagation of primary human mammary epithelial populations while preserving lineage identity across passages. We identify intrinsically distinct cell cycle response of luminal progenitors and basal cells to irradiation stress where the former engages both G1/S and G2/M checkpoints to achieve cell cycle arrest and the latter relies on the G2/M checkpoint. These lineage distinctions are diminished in germline BRCA1 mutation carriers with an attenuated G1/S checkpoint in luminal progenitors. Paired transcriptomic-proteomic profiling of acute irradiation response uncovers BRCA1+/- luminal progenitor population with sustained AKT-mTOR signaling and compromised cell cycle arrest marking an early deviation in the stress response of these purported cells-of-origin of aggressive breast cancers known to arise in BRCA1 germline mutation carriers. Our study provides a functional framework for determining critical events in the expansion of genomically altered mammary epithelial cells in the high-risk breast to enable future preventive interventions.

cell biology↗

Dual-Lipa: A sequential multi-omic subcellular landscape map of mouse heart

Spatial multi-omics can provide a unique understanding in molecular organisation and heterogeneity of organs including the heart. Heart function is dependent on the abundance and the spatial arrangement of proteins and lipids. Yet, an integrated multi-omics landscape of the heart at subcellular scale remains unknown. Here, we used a sequential lipid-proteomic analytical pipeline applied to the mouse heart to identify, map, and integrate lipid and protein features, revealing coordinated distinct molecular networks within defined subcellular niches. Here, we benchmark this dual extraction workflow for integrated global proteome-lipidome analyses to demonstrate its performance. We developed conserved subcellular proteome of mouse heart across 14 niches and applied the knowledge of subcellular proteome to spatially resolve the heart lipidome, identifying unique lipid features from different subcellular niches, including mitochondria (e.g., cardiolipin, LPC) and plasma membrane-enriched lipids (e.g., plasmalogens). We identified sex-dependent molecular differences in heart subcellular proteome between male and female, including RNA-protein complexes, mitochondrial calcium handling and immune regulatory pathways. We demonstrate that lipid-protein integrated multi-omics analysis of the heart by dual extraction workflow and mass spectrometry could enable previously unidentified discoveries in heart molecular composition and organisation and spatial cardiac biology. HighlightsO_LIResolved tissue-wide subcellular architecture of cardiac tissue through simultaneous high-resolution proteomics and lipidomics profiling. C_LIO_LISystematically evaluated MS-compatible dual extraction strategies for integrated proteome-lipidome recovery and performance. C_LIO_LIProteomics revealed major sex-dependent differences in mouse left ventricles, primarily involving cellular metabolism, immune regulation, detoxification pathways, and signalling responses. C_LIO_LILipidomics identified strong sex-specific lipid signatures, including differences in omega-3 vs omega-6 fatty-acid containing lipid species, triacylglycerides, and acylcarnitines. C_LIO_LIDeveloped supervised machine-learning models to classify 14 subcellular niches from tissue-wide fractionation proteomics and identified a conserved core subcellular proteome. C_LIO_LIApplied the tissue-wide subcellular proteome model to infer lipid subcellular localisation, revealing mitochondria-enriched lipids (e.g., cardiolipin, LPC) and plasma membrane-enriched lipids (e.g., plasmalogens) in the mouse left ventricle. C_LIO_LIMapped sex-specific subcellular distribution in the heart, highlighting pathways linked to RNA-protein complexes, mitochondrial calcium handling, and immune regulatory networks. C_LI

biochemistry↗

Cell-type specific allelic dampening of sex-linked genes in sex chromosome aneuploidy

Common sex chromosome aneuploidies (SCAs) often present with cognitive and cardiovascular dysfunction in humans. To address SCA effects on gene expression and DNA methylation in relevant cell types, we differentiated neural precursor cells (NPCs) and cardiomyocytes (CMs) from human induced pluripotent stem cells (hiPSCs) with different numbers of sex chromosomes, including isogenic and independent lines. As expected, the expression of genes that escape X inactivation (escapees) mostly increases with the number of inactive X chromosomes (Xi). However, allelic analysis shows dampening of escapees specifically on the Xi in XXY compared to XX in both NPCs and CMs, revealing a novel type of dosage compensation in SCA. In contrast, Y-linked gene expression is higher in XXY versus XY NPCs, but the opposite is observed in CMs. This may explain the greater number of differentially expressed autosomal genes in NPCs versus CMs with an added Y chromosome, while effects of added X chromosomes are similar between cell types. Concordantly, changes in autosomal DNA methylation are mainly driven by the presence of a Y chromosome. These findings highlight the cell-type specificity of sex-linked and autosomal gene regulation in SCA conditions. HighlightsO_LISex chromosome aneuploidy induces cell-type specific changes in gene expression C_LIO_LIDampening of the inactive X chromosome in XXY alleviate X overexpression C_LIO_LIHigh Y-linked gene expression in XXY neuronal precursor cells but not cardiomyocytes C_LIO_LISex chromosome aneuploidy disrupts sex biases in autosomal gene expression C_LI

molecular biology↗

When Multimodal Fusion Fails: Contrastive Alignment as a Necessary Stabilizer for TCR--Peptide Binding Prediction

Multimodal learning is commonly assumed to improve predictive performance, yet in biological applications auxiliary modalities are often imperfect and can degrade learning if fused naively. We investigate this problem in TCR-peptide binding prediction, where sequence embeddings from pretrained protein language models are strong and transferable, but structure-derived residue graphs are built from predicted folds and heuristic discretization. In this setting, structural views can be noisy, inconsistent, and difficult to optimize jointly with sequence features. We introduce TRACE, a lightweight multimodal framework that encodes each entity (TCR and peptide) with parallel sequence and graph towers, then applies CLIP-style intra-entity contrastive alignment before interaction modeling. The alignment objective regularizes representation geometry by encouraging modality consistency for the same biological entity, thereby preventing unstable graph signals from dominating fusion. Across protocol-aware TCHard RN evaluations, naive sequence+graph fusion frequently underperforms a sequence-only baseline and can collapse toward near-random behavior. In contrast, TRACE consistently restores and improves performance. Controlled noise and supervision sweeps show that these gains persist under increasing graph corruption and positive-label scarcity, indicating that alignment is especially important when training conditions are hard. Our results challenge the assumption that adding modalities is inherently beneficial. Instead, they highlight a central principle for robust multimodal bioinformatics: performance depends not only on what modalities are used, but on how their interaction is constrained during optimization. TRACE provides a simple and general recipe for leveraging imperfect structural information without sacrificing stability.

bioinformatics↗

CoLa-VAE: Cell-Cell Communication-aware Variational Autoencoder with Dynamic Graph Laplacian Constraints

Single-cell RNA sequencing provides a powerful view of cellular heterogeneity, but its sparsity and dropout noise remain major obstacles for recovering biologically meaningful gene expression programs and for downstream analyses that depend on reliable expression measurements. Ligand-receptor-based cell-cell communication inference is such analysis, missing ligand or receptor expression can cause substantial false negatives in sparse single-cell data. Here, we present CoLa-VAE, a cell-cell communication-aware variational autoencoder that jointly learns latent representations and denoised expression profiles by incorporating ligand-receptor-derived communication topology through dynamic graph Laplacian regularization. Rather than treating denoising as a secondary output of representation learning, CoLa-VAE uses denoised expression to iteratively refine communication estimates and uses the resulting communication structure to guide both latent organization and expression reconstruction. In addition to improving latent space organization and producing robust denoised expression matrices, CoLa-VAE-denoised matrices also improved downstream biological analyses, including the detection of robust differential cell-cell communication programs, mitigation of batch-associated variation and enhanced spatial transcriptomic deconvolution when spatially constrained communication structure was incorporated. Together, these results establish CoLa-VAE as a communication-guided denoising and representation learning framework that recovers biologically meaningful expression signals from sparse single-cell and spatial transcriptomic data, enabling more sensitive and reliable downstream analysis.

bioinformatics↗

Can category-selective cortex predict categorisation behaviour?

One of the distinctive features of the human visual system is the presence in occipito-temporal cortex (OTC) of regions that show preferential activation to specific categories of visual objects. To understand how this selectivity relates to categorisation behaviour, studies have employed a distance-to-bound approach (DTB), where multivariate brain activity is used to estimate a decision boundary, from which behavioural performance can be predicted. Using this approach, correlations have been found between activity in OTC, and behavioural performance when carrying out certain categorisation tasks. However, it remains unclear what determines where in OTC this correlations can be found, and with which categorisation tasks they can be found. Here, we bridged this gap by relating category-selective regions of OTC, to behavioural performance while participants categorised images as belonging or not to their preferred categories. We adopted a more basic approach and considered simple, univariate activity, rather than relying on decoding to build our DTB. Our results show that activation in regions selective to faces (FFA & OFA), bodies (EBA), and scenes (PPA), is sufficient to predict behavioural performance while categorising images as being faces, bodies, or scenes, respectively. These results are largely consistent across reaction time and motor movements, and generalise to animacy classification. Overall, our data adds to evidence that category-selective regions in OTC can serve to guide categorisation behaviour, and underlines the validity of the DTB approach to address this relationship.

neuroscience↗

L-cysteine inhibited the growth of Vibrio parahaemolyticus via increasing the ROS level

The emergence of multidrug-resistant Vibrio parahaemolyticus poses a severe threat to mariculture sustainability, highlighting the urgent need for eco-friendly antimicrobial agents. In this study, we demonstrated that L-Cysteine (L-Cys) functions as an inhibitor of V. parahaemolyticus, with a minimum inhibitory concentration of 7.5 mM. Microscopic observation and viability assays revealed that L-Cys compromises bacterial membrane integrity, ultimately leading to cell death. Further investigation indicated that the antibacterial effect is primarily attributed to the intracellular production of hydrogen sulfide (H2S) generated by L-Cys metabolism. Transcriptomic and biochemical analyses showed that L-Cys induced metabolic reprogramming by suppressing fatty acid {beta}-oxidation, one-carbon metabolism, and antioxidant enzymes. This disruption of redox homeostasis results in accelerated accumulation of reactive oxygen species (ROS). In addition to its antibacterial effect, L-Cys also effectively reduced the virulence factor of bacterial motility. Finally, L-Cys demonstrated broad-spectrum antimicrobial activity against other pathogenic Vibrio species, including V. alginolyticus and V. anguillarum. Our findings suggest that L-Cys is a promising antimicrobial agent inducing ROS to mediate membrane disruption, with the advantages of cost-effectiveness and environmental safety for controlling vibriosis. ImportanceVibrio parahaemolyticus is a significant pathogen in aquaculture and a common cause of seafood-borne gastroenteritis worldwide. The increasing prevalence of antibiotic-resistant strains of this bacterium highlights the need for alternative control agents. This study shows that L-cysteine (L-Cys) inhibits the growth of V. parahaemolyticus. Our data indicate that L-Cys is metabolized to produce hydrogen sulfide, which contributes to the accumulation of ROS and disrupts bacterial membrane integrity. Additionally, L-Cys reduces bacterial motility and shows inhibitory effects against other Vibrio species. These findings suggest that L-Cys may represent a useful agent for managing Vibrio infections in aquaculture settings.

microbiology↗

A methylome-derived m6-dAMP trigger assembles a PUA-Cal-HAD immune filament that depletes dNTPs to abort phage infection

Bacteria must distinguish phage attack from normal homeostatic processes, yet the danger signals that trigger many defence systems remain unknown. Here, we show that a PUA-Calcineurin-CE-HAD module from Escherichia coli ECOR28 confers broad anti-phage protection by binding Dam-methylated deoxyadenosine monophosphate (m6-dAMP) generated during phage-induced chromosome degradation. Ligand binding converts a preassembled PUA-Calcineurin-CE hexamer loaded with six HAD phosphatases into a polymerising filament. The filament acts as a high-flux dNTP sink through a two-enzyme cascade: HAD first dephosphorylates dATP to dADP, and Calcineurin-CE then converts dADP to dAMP. dNTP collapse halts phage replication and enforces abortive infection. Multiple mobile-element DNA mimic proteins block filament assembly, revealing a direct phage counter-defence. More broadly, our findings extend a conserved, cross-kingdom paradigm of immune filament assembly to nucleotide-depletion antiviral defence and suggest modified-nucleotide sensing by related PUA-Calcineurin-CE modules as a widespread, underappreciated bacterial strategy.

microbiology↗

Ser129 Phosphorylation Paradox: Non-phosphorylated α-Synuclein Drives Parkinson' s Disease-like Pathogenesis in Vivo

Accumulation of phosphorylated -synuclein at serine 129 is a hallmark of Parkinsons disease (PD), but its pathogenic role remains controversial. We conducted longitudinal studies using non-phosphorylatable S129A and phosphomimetic S129D -synuclein global knock-in mice. Unexpectedly, the S129A mice--rather than S129D mice--developed reproducible olfactory, motor, and cognitive deficits, dopaminergic dysfunction and neurodegeneration, -synuclein insolubility, and Lewy-like inclusions by 3 to 9 months, with progressive worsening up to 12 months of age. Spatial transcriptomics and electron microscopy revealed mitochondrial, synaptic, and protein ubiquitination abnormalities in the substantia nigra of S129A -synuclein mice. Viral vector-mediated nigral overexpression of S129D--synuclein or systemic administration of an anti--synuclein-aggregation drug partially alleviated the early neurological phenotypes of S129A mice. These results implicate non-phosphorylatable -synuclein as a direct pathogenic driver for PD.

neuroscience↗

An inherent T cell-activating mRNA delivery platform for in vivo CAR T generation

The clinical success of CAR T cell therapy has underscored the need for scalable, non-invasive strategies for in vivo T cell engineering. Although mRNA delivery offers a promising alternative, current lipid-based vectors lack intrinsic T cell tropism and often rely on antibody conjugation, complicating manufacturing and raising safety concerns. Here we present an inherent T cell-activating polymer-lipid nanoparticle (ERTLNPs) that enable ligand-free, efficient mRNA transfection and activation of T cells in vivo. ERTLNPs, composed of p-toluenesulfonyl arginine (RT)-functionalized polyethylenimine (denoted as PEI-RT) and helper lipids, preferentially accumulate in the spleen following systemic administration. Without exogenous stimulation, ERTLNPs intrinsically activate T cells, triggering robust mRNA expression and proliferation. Mechanistically, ERTLNPs engage the PI3K/AKT/mTOR signaling axis to reprogram T cell metabolism, promoting expansion while restraining exhaustion. Systemic delivery of mRNA encoding fibroblast activation protein chimeric antigen receptor (mFAP CAR) via ERTLNPs leads to in situ generation of functional CAR T cells, which efficiently eliminate pathological fibroblasts in models of cancer and fibrosis, with minimal off-target effects. This ligand-free, metabolically reprogramming mRNA delivery platform provides a clinically translatable approach for in vivo CAR T cell generation and broadens the landscape of non-viral immunotherapeutic engineering.

bioengineering↗

The spatiotemporal structure of neural activity in motor cortex during reaching

Intracortical brain-computer interfaces (BCI) leverage knowledge about neural representations to translate movement-related neural activity into actions. BCI implants have targeted broad cortical regions known to have relevant motor representations, but emerging technologies will allow flexible targeting to specific neural populations. The structure of motor representations in neural populations across frontal motor cortices, which span centimeters, has not been well characterized. Here, we investigate how motor representations and population dynamics (temporal coordination) vary across a large expanse of frontal motor cortices. We used high-density, laminar, microelectrode arrays to record many neurons and then sampled neural populations across frontal motor cortex in two monkeys while they performed a reaching task. Our experiments allowed us to map neuronal activity across three spatial dimensions and relate them to movement. Target decoding analysis revealed that target direction information (one key aspect of task information) was heterogeneously distributed across the cortical surface and in depth. Similarly, we found that the temporal dynamics of different neural populations was highly variable, but that the amount of task information predicted which neural populations had similar dynamics. The neural populations with the most similar dynamics were composed of neurons with high task information regardless of spatial location. Our results highlight the spatiotemporal complexity of motor representations across frontal motor cortex at the level of neurons and neural populations, where well-learned movements consistently recruit a spatially distributed subset of neurons. Further insights into the spatiotemporal structure of neural activity patterns across frontal motor cortex will be critical to guide future implants for improved BCI performance. Significance StatementMotor brain-computer interfaces (BCI) translate neural activity into movement, but how to target implants within motor cortices to maximize performance remains unclear. We used high-density recordings of neural activity spanning a large cortical area and related them to movement to map the spatial distribution of task information and the evolution of neural population activity over time. Our measurements revealed that neurons with the most task information were highly distributed across cortex yet also evolved coherently in time, suggesting that spatially distributed neurons coordinate to control movements. Our results provide new links between neuron- and population-level maps of motor representations, and highlight the complex spatiotemporal structure of activity that may need to be considered when designing next-generation BCIs.

neuroscience↗

Suppressing cortical glutamatergic neurons produces paradoxical interictal discharges and seizures

IntroductionSeizures are traditionally attributed to excessive excitation or deficient inhibition, yet recent clinical and slice data show they can also paradoxically arise when inhibition outweighs excitation. We chemogenetically suppressed neocortical glutamatergic neurons to test whether such suppression elicits epileptic activity in vivo. MethodsCaMKII-driven Gi-coupled hM4Di or Gq-coupled hM3Dq Designer Receptor Exclusively Activated by Designer Drug (DREADDs) were expressed in cortical glutamatergic neurons of Rasgrf2-jGCaMP8m and wildtype C57BL/6J mice. Widefield calcium imaging and 32-channel transparent electrocorticography were performed before and after systemic clozapine-N-oxide (CNO; 1.25-5 mg kg {superscript 1}). ResultsDREADD activation induced intermittent, large-amplitude, synchronized calcium transients confined to the CaMKII-hM4Di focus, accompanied by focal ECoG spikes that persisted for >3 h and sometimes evolved into seizures. By contrast, CNO activation of excitatory neurons via CaMKII-hM3Dq DREADDs desynchronized activity without epileptiform discharges. The same process duplicated in wild-type animals provoked similar epileptiform discharges. ConclusionSelective suppression of excitation can paradoxically drive cortical networks into hypersynchronous, epileptic states, challenging the simple excess-excitation model of ictogenesis. These findings highlight that seizures may result from relative inhibitory dominance, and that considering this excess inhibition mechanism could inspire new therapeutic approaches.

neuroscience↗

Clonal dynamics shaped by diverse drug-tolerant persister states in melanoma resistance

Most advanced melanomas initially respond to targeted therapy but eventually relapse. Rather than acquiring new mutations, resistance is driven by drug-tolerant persister cells that enter a reversible drug-refractory state. We developed MeRLin, a high-resolution lineage tracing platform integrating cellular barcoding, single-cell transcriptomics, RNA fluorescence in situ hybridization (FISH), and computational analyses to track clonal and transcriptional dynamics in patient-derived melanoma models during prolonged therapy. Clonal dynamics revealed that persister subpopulations first responded to treatment but persisted and expanded during minimal residual disease, ultimately leading to tumor recurrence. Pre-treatment melanoma populations diversified into four conserved persister states characterized by stress-like, lipid metabolism, PI3K signaling, and extracellular matrix remodeling programs associated with adaptive resistance. Spatial transcriptomics showed the organization of these adaptive programs and a complex signaling network of autocrine and paracrine interactions among persister subpopulations. Barcoded RNA-FISH enabled spatial mapping of clonal identity and gene expression, revealing in situ co-localization of a dominant resistant clone with SLC2A1 expression. MeRLin provides a robust framework for dissecting cancer heterogeneity and identifying vulnerabilities in persister populations.

cancer biology↗

Customized and rapid observational delimiting surveys for plant pests based on transect data and scouting

We have created a complete, standard methodology for designing customized observation-based delimiting surveys for localized incursions of non-endemic plant pests. We propose using transects customized for the species and situation to do the following: O_LICollect data for [~]120 detections C_LIO_LIFit an exponential function to the histogram using an extreme values analysis peaks-over-threshold (EVA POT) technique C_LIO_LICalculate a percentile-based boundary distance that accounts for two-dimensional (radial) spread C_LIO_LIUse field scouting for verification C_LI We call the approach "Delimitation via Transect Data and Scouting," or DTDS. In simulations we compared DTDS plans to published survey plans for the Asian longhorned beetle (ALB; Anoplophora glabripennis (Motschulsky)), the fungus Phyllosticta citricarpa (Guigci), and the tomato brown rugose fruit virus (TBRFV; Tobamovirus). The EVA POT method avoided problems with highly skewed data, and ninety-ninth percentile boundary estimates from it that accounted for radial dispersal always contained the adventive populations. Based on sample sizes, time required, and success (containment) rates the DTDS surveys were efficient and effective. For ALB and TBRFV, DTDS surveys reduced sample sizes and durations by 77 percent or more. For P. citricarpa, the DTDS design greatly increased the sample area, but eliminated 6% (scenario 1) and 68% (scenario 2) failure rates in the original plan. The DTDS methodology synthesizes established techniques in a novel way, providing a standardized, clear, and often rapid process for designing customized, transect-based observation-based delimitation surveys that are both efficient and effective. The approach has clear management and financial benefits, and should facilitate quicker, improved decision making. Key messagesO_LIDTDS is a customizable delimitation survey design method based on transect sampling and scouting C_LIO_LITransects designed to produce [~]120 positives facilitate efficient sampling of incursion areas C_LIO_LIBoundaries can be accurately determined with uncertainty using extreme values analysis of the distance data C_LIO_LICase studies demonstrated that using DTDS always contained incursions and often greatly reduced survey effort C_LI

ecology↗

APOE genotype confers context dependent neurovascular vulnerability in immune-vascularized human forebrain organoids

The APOE gene is a major genetic determinant of neurovascular and immune function, yet the mechanisms by which its isoforms modulate brain vulnerability to pathogenic stress remain incompletely understood. Here, we employ isogenic human iPSC-derived immune-vascularized--Forebrain Organoid-based Multicellular Assembled Cerebral Organoids (FORMA-COs)--to dissect isoform-specific responses to a clinically relevant viral challenge. We find that APOE2/2 and APOE4/4 FORMA-COs exhibit heightened viral RNA burden and distinct neuroinflammatory profiles compared to APOE3/3. Specifically, APOE4/4 promotes IL-1 and VEGFA induction, whereas APOE2/2 leads to elevated TNF-{beta} and VEGFA protein accumulation, indicating divergent pathways of injury. Integrated transcriptomic analyses, combined with known and predicted APOE protein-protein interaction networks, reveal genotype-dependent enrichment of cytokine signaling, angiogenic remodeling, and immune dysregulation. In vivo validation using humanized mouse models corroborates APOE genotype- specific vascular remodeling, microglial activation, and oligodendrocyte perturbation. These findings demonstrate that APOE genotype confers context-specific susceptibility to neuroimmune and vascular injury, providing insight into genetic risk mechanisms underlying infection-related and neurodegenerative brain disorders.

neuroscience↗

N1-methylpseudouridine mRNA modification enhances efficiency and specificity of gene overexpression by preventing Prkra-mediated global translation repression

In vitro transcribed messenger RNA (IVT mRNA) has emerged as a pivotal tool in mRNA-based therapies and has been extensively employed in gene function studies and genetic tool applications. However, the IVT process generates double-stranded RNA (dsRNA) by-products that are recognized by dsRNA sensors, triggering innate immune responses. In this study, we comprehensively analyzed the detrimental effects of dsRNA by-products on early zebrafish embryos, revealing that these by-products induce cell necrosis and delay maternal-zygotic transition by reducing global translation efficiency via Prkra, a recently identified dsRNA sensor in pluripotent cells. Importantly, we demonstrate that N1-methylpseudouridine (m1{varphi}) modification of IVT mRNAs effectively mitigates these adverse effects, as m1{varphi}-modified dsRNAs exhibit significantly lower binding affinity to the Prkra dimer. Our findings underscore a previously overlooked challenge in the use of IVT mRNA in early embryos and offer a robust solution to enhance the fidelity of mRNA applications. Furthermore, we elucidate that m1{varphi} modification minimizes the dsRNA-induced stress response in pluripotent cells through a distinct mechanism.

developmental biology↗

Improving design and normalization of multiplex proteomics study

Advances in multiplex mass spectrometry-based technologies have enabled high-throughput, quantitative proteome profiling of large cohort. However, certain experimental design configurations can amplify sample variability and introduce systematic biases. To address these challenges, we incorporated two novel features in a recent proteogenomic investigation: (1) the inclusion of two reference samples within each mass spectrometry run to serve as internal standards, and (2) the analysis of each specimen as technical replicates across two distinct mass spectrometry runs. Building on these enhancements, we present ProMix, a flexible analytical framework designed to fully leverage these supplementary experimental components. Using both simulated and real-world datasets, we demonstrate the improved performance of ProMix and highlight the advantages conferred by these refined experimental design strategies.

bioinformatics↗