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Feng, Y.

Publications and source records attributed to Feng, Y..

At least 55 records · Page 3Linked to original sources

BEEP Learning: Multi-View Image Decomposition for Massively Multiplexed Biological Fluorescence Microscopy

Fluorescence imaging with spectrally variant fluorophores allows the spatial mapping of biological structures with exquisite cellular and molecular specificity. However, the ability to robustly discriminate multiple fluorophores in any single imaging experiment is greatly hindered by the broad emission spectra of bio-compatible fluorophores and the large contribution of noise in low-energy regime fluorescence microscopy. In this study, we propose a novel machine learning framework, Bleaching-Excitation-Emission Photodynamics (BEEP) learning, that exploits multiple discriminatory features of fluorescent dyes to greatly expand the number of distinguishable objects in an image by integrating emission spectra, excitation variability, and bleaching dynamics into a unified multi-view, fluorescence unmixing approach. Our method is built upon a rank-one-tensor-based generalized linear model and leverages two biophysically grounded assumptions: consistent spectral and bleaching behaviors under fixed excitation, and invariant fluorophore abundances across excitations. We first extract excitation-specific spectral and bleaching signatures from reference images, and then use them to estimate abundances in complex mixtures. Experimental results on both simulated and real images of microbial populations demonstrate that our approach significantly outperforms conventional and partially multi-view methods, offering improved robustness and accuracy in highly multiplexed fluorescence imaging.

biophysics↗

Distributional and Centile Calibration of Diffusion Tensor Imaging Normative Models as Training Sample Sizes Increase to 40,000 Subjects

Normative modeling (NM) is a powerful framework for quantifying individual deviations in brain structure and function relative to a population reference. However, its clinical utility depends on well-calibrated models trained on heterogeneous datasets such as those found in neuroimaging. Here, we systematically examine the effect of training sample size on the distributional and centile calibration of hierarchical Bayesian regression (HBR)-based NMs. Using multisite 3D diffusion MRI scans of the brain from 54,583 subjects, spanning almost the entire lifespan (age: 4-91 years), we trained NMs of white matter fractional anisotropy, a key microstructural metric, on subsamples ranging from 5,000 to 40,000 subjects. HBR was modeled with a Sinh-Arcsinh likelihood. Model calibration was evaluated using Kernelized Stein Discrepancy (KSD) to assess distributional agreement of Z-scores with the standard normal distribution; we also used Mean Absolute Centile Error (MACE) to quantify centile accuracy. Both metrics showed consistent and substantial improvements as the training sample size increased, indicating reduced posterior uncertainty and improved estimation of distributional parameters, particularly at the centile extremes. These results demonstrate that large training cohorts are essential for well-calibrated NMs derived from heterogeneous neuroimaging data and highlight the importance of large-scale data aggregation for reliable individual-level inference.

bioinformatics↗

Tractometry-Based Quantification of Along-Tract White-Matter Hemispheric Asymmetry in Alzheimer's Disease

White-matter hemispheric asymmetry is a fundamental property of human brain organization and is known to change in aging, neurodevelopment, and neurodegenerative disorders. Tractometry analyzes diffusion-derived microstructural measures along the full length of tracts, localizing changes to specific tract-segments rather than collapsing tracts into a single value. Yet, existing frameworks lack a principled way to quantify left-right hemispheric asymmetries along homologous tracts. Here, we introduce an asymmetry-aware tractometry framework that integrates a symmetric white-matter atlas with BUAN (Bundle Analytics) to enable anatomically consistent, along-tract comparison of homologous pathways. By defining homologous bundles with a shared template and consistent orientation, each left-hemisphere segment is directly matched to its right-hemisphere counterpart, enabling principled, segment-wise comparison and revealing spatially localized asymmetries along-tract. Applying this framework to diffusion MRI data from the Alzheimers Disease Neuroimaging Initiative (ADNI) comprising 1,215 subjects, we demonstrate how this approach reveals systematic left-right asymmetries across major white-matter pathways and show how these patterns differentiate cognitively normal (CN) individuals from those with mild cognitive impairment (MCI) and dementia. This method provides a sensitive and anatomically grounded tool for studying hemispheric specialization and its disruption in aging and disease, and establishes a general approach for asymmetry-aware tractometry in population neuroimaging studies.

neuroscience↗

Soluble DLK1 secreted by telomere-shortening-induced senescent microglia impairs oligodendrocyte functions and alters neuronal activity

Aging is the major risk factor for neurodegenerative disease, yet the mechanisms linking physiological aging to brain dysfunction remain unclear. Because telomere erosion is a hallmark of aging, we examined its impact on glial and neuronal physiology. Telomere shortened mice showed lipofuscinosis, hypomyelination, microglial atrophy, and cognitive deficits. Single nuclei RNA-seq revealed accelerated glial aging, elevated microglial senescence pathways, and impaired oligodendrocyte functions. Inducing senescence in human iPSC derived microglia with shortened telomeres identified soluble DLK1 as a novel senescence associated ligand. sDLK1 was increased in the cerebrospinal fluid of telomere shortened and naturally aged mice, and this increase was eliminated by microglial depletion. AAV delivery of sDLK1 in vivo caused hypomyelination and blocked oligodendrocyte lineage progression, demonstrating the detrimental nature of excessive sDLK1. In human iPSC systems, sDLK1 impaired oligodendrocyte maturation and altered calcium signaling in excitatory neurons. These findings identify microglial senescence as a core consequence of telomere shortening and reveal sDLK1 as a microglia-derived senescence ligand that drives oligodendrocyte and neuronal dysfunction in aging.

neuroscience↗

A Bear-Specific Coding Exon in TMEM41B Is Associated with Cold Adaptation

AbstractBears exhibit an unusual form of hibernation in which core body temperature remains relatively high despite profound suppression of whole-body metabolism. How such a warm yet hypometabolic state is achieved remains poorly understood. Here, through integrative analysis of 238 RNA-seq datasets spanning seven species, we identify transmembrane protein 41B (TMEM41B) as an evolutionarily conserved factor associated with thermogenic capacity. Loss of Tmem41b in mice and Drosophila results in severe cold intolerance, whereas its overexpression enhances thermogenic performance, supporting a conserved role in heat production. Comparative genomic analyses reveal a bear-specific 51-amino acid N-terminal extension in TMEM41B, arising from a 5' untranslated region mutation that converts a premature stop codon into coding sequence. Interactome profiling indicates that this bear-specific isoform differs from the canonical TMEM41B in its protein interaction landscape, including reduced association with components of mitochondria-associated endoplasmic reticulum membranes such as voltage-dependent anion-selective channel protein 1 (VDAC1). Consistent with this altered interaction profile, the extended isoform is associated with reduced mitochondrial oxidative activity. Functional analyses further suggest that the 51- amino acid extension modulates multiple cellular programs, including suppression of oxidative phosphorylation and myogenic differentiation alongside activation of osteogenic pathways, collectively biasing cells toward a hypometabolic state. Notably, expression of the polar bear TMEM41B isoform in mice induces a torpor-like phenotype under fasting conditions. Together, these findings identify TMEM41B as a conserved regulator of thermogenic capacity and suggest that evolutionary modification of its N terminus may contribute to metabolic suppression and energy conservation during bear hibernation.

evolutionary biology↗

Automating the Construction of Contextualized Biomedical Knowledge Graphs for Scientific Inference

Biomedical interactions are inherently dynamic, often shifting or even reversing under specific physiological states. However, existing extraction methods simplify these complex mechanisms into context-agnostic binary associations, resulting in semantic loss and contradictory evidence. Here, we present AutoBioKG, an end-to-end framework that constructs context-aware knowledge graphs by leveraging composite triples to encode environmental conditions and entity attributes alongside core relationships. Powered by an open information extraction model trained on BioOpenIE and further refined through self-training with pseudo-labels from unlabeled literature, the framework exhibits broad generalization. Notably, AutoBioKG achieved the highest zero-shot F1 across DDI, ChemProt, and BioRED, outperforming the best-performing baseline on each benchmark by 3.6-17.8 percentage points. Furthermore, AutoBioKG-derived graphs outperformed existing approaches on yes/no, factoid, and list questions in the BioASQ biomedical question-answering evaluation, particularly for queries requiring fine-grained contextual information. Together, these results support AutoBioKG as a scalable framework for transforming unstructured literature into structured, context-aware biomedical knowledge.

bioinformatics↗

Engineering Functionality-Optimized Fully Human B7-H3 CAR T Cells for Enhanced Solid Tumor Therapy

B7-H3 is a cell surface protein overexpressed in many solid tumors and an attractive target for chimeric antigen receptor (CAR) T cell therapy. The most clinically advanced B7-H3 CARs are derived from murine monoclonal antibodies (mAbs) 376.96 and MGA271, which are now in phase 1/11 trials. However, non-human mAb sequences can provoke immune responses, leading to CAR T-cell rejection and therapeutic failure. Although scFv humanization reduces this risk, residual foreign residues within the variable domains remain. To overcome this limitation, we used in vitro phage display to generate fully human B7-H3-specific scFvs for CAR design. In pancreatic cancer, neuroblastoma, and glioblastoma xenograft models, CAR T cells incorporating the lead human binder Y111 were well tolerated and demonstrated superior antitumor activity compared with 376.96- and MGA271-based CARs. Y111 CAR treatment induced complete responses, tumor rejection, and significant survival benefits, identifying Y111 as a promising fully human B7-H3 CAR for solid tumors.

immunology↗

A PIWI protein-dependent DNA N6-adenine methylation pathway in Oxytricha protects genomic sequences from deletion

The ciliate Oxytricha undergoes massive genome rearrangements during development to produce a functional nucleus from an encrypted zygotic genome. PIWI-interacting small RNAs protect DNA regions against deletion, but how that protective mark is established has been a mystery. Recently our lab discovered MTA1, a methyltransferase that catalyzes DNA N6-adenine (6mA) methylation. Both MTA1 and the Oxytricha Piwi protein, Otiwi1, are required for development, and Otiwi1 mutation eliminates 6mA signal. To examine the role of 6mA, we analyzed its genome-wide distribution across development in wild-type and MTA1 mutant backcrossed cells. We find specific and abundant enrichment on retained sequences, suggesting a protective role for this epigenetic mark. Furthermore, programmed retention of a DNA region that is normally deleted leads to accumulation of new 6mA marks on the ectopically retained DNA sequence. Together, these results suggest that piRNA-guided 6mA DNA methylation leads to protection of DNA sequences against deletion during nuclear differentiation. HighlightsO_LIDNA N6-methyladenine accumulates on retained DNA regions during Oxytricha development. C_LIO_LImta1 mutant backcrosses have disrupted DNA methylation and a developmental delay. C_LIO_LIDNA N6-adenine methylation during genome rearrangement requires the presence of Otiwi1. C_LIO_LIProgrammed retention of a germline-limited region leads to developmental methylation. C_LI

molecular biology↗

INS-fMRI reveals a mesoscale limbic organization associated with medial pulvinar in primates

The experience of emotion comprises not only the feelings (happiness, sadness), but also behavioral expression, internal awareness, and the bodys physiological response. However, it remains unclear how the brain integrates these disparate aspects of emotion. Here, to examine functional connectivity in the limbic system of macaque monkeys, we combined focal Infrared Neural Stimulation of a sensory gateway (medial pulvinar PM), with ultra-high-field 7T functional magnetic resonance imaging (INS-fMRI). We find connected sites are mesoscale (millimeter-scale) in size and arranged in patchy patterns across cingulate, insula, and amygdala. Non-overlapping connections evoked from three sequential stimulation sites in PM form clusters of multi-site integration, and appear related to known functional organization within these limbic regions. We suggest these mesoscale functional connections link the limbic axes of motor expression (cingulate), interoception (insula), and emotion-related processing (amygdala), and that, much like visual system, the limbic system is fundamentally quite orderly at mesoscale. Our results underscore the importance of millimeter-scale precision and organization in diagnosis and treatment of affective disorders.

neuroscience↗

CAR-T-drug conjugate against solid tumor

Chimeric antigen receptor (CAR)-T cell therapy has been clinically successful in hematologic cancers but faces challenges in solid tumors, primarily due to limited tumor infiltration, immunosuppressive tumor microenvironments (TME), and antigen heterogeneity. While combining CAR-T cell therapy with chemotherapy can enhance antitumor activity, this often leads to substantial systemic toxicity. In this study, we introduce CAR-T-drug conjugate (CAR-T-D-C), a new class of dual-functional therapeutics that effectively addresses these obstacles by integrating click chemistry for precise conjugation of cytotoxic agents onto antigen-specific CAR-T cells. By transforming the hostile TME into an ally, this approach facilitates localized delivery of cytotoxic payload directly to the tumor site, enhancing the overall effectiveness of CAR-T therapy in solid tumors. CAR-T-D-Cs with different CAR-T cell binders exhibit robust antitumor activity across diverse solid tumor models, including both human tumor xenografts and syngeneic models. Spatial transcriptomic studies reveals that CAR-T-D-C achieves improved CAR-T tumor infiltration and functional activation within the TME. Compared to conventional CAR-T therapy, CAR-T-D-C markedly enhances immune cell infiltration, augments effector functions, promotes antigen spreading, amplifies systemic immune responses, and improves overall anti-tumor immunity. CAR-T-D-C represents a versatile therapeutic concept that combines the potency of small molecule drugs and the specificity of CAR-T cells as a 2-in-1 immunochemotherapy for treatment of solid tumors.

immunology↗

AlphaFold 3-powered discovery of phage proteins that inhibit bacterial transcription

Phages are the most abundant biological entities on Earth and play central roles in bacterial evolution and the emergence of new pathogens. Many phages encode proteins that specifically inhibit host RNA polymerase activity, thereby sabotaging and, in some cases, hijacking the host transcription machinery to serve their needs. Identification and characterization of these transcription inhibitors not only provide insights into the logic of transcription regulation but also inspire the design of antibiotics targeting bacterial transcription. Traditional methods for identifying new phage proteins that inhibit bacterial transcription are labor-intensive and require access to live phages. To overcome these limitations, we developed a highly efficient pipeline for AlphaFold 3-guided discovery of phage proteins that inhibit bacterial transcription. Using this pipeline, three phage proteins were identified and characterized. Structural and biochemical analyses demonstrated that these phage proteins bind to distinct sites on RNA polymerase and inhibit transcription via unprecedented mechanisms. This study showcases the power of AlphaFold 3 in discovering novel binders of large protein complexes, and the pipeline developed here could be readily adapted to screen modulators of other large targets, such as the ribosome, proteasome, and CRISPR-Cas systems.

molecular biology↗

The role of autoproteolysis and mitoribosomal proteins in regulation of mitochondrial LACTB tumor suppressor

Tumor suppressors represent one of the first lines of defense against malignant transformation and their inactivation in cells leads to onset of tumorigenesis. Cancer cells employ a variety of ways to inactivate cellular tumor suppressors, such as their epigenetic silencing or mutagenesis. Less understood are mechanisms by which cancer cells inactivate tumor suppressors post-translationally. Here, we uncovered a previously undescribed post-translational strategy that cancer cells use to inactivate the potent mitochondrial tumor suppressor LACTB in breast cancers. We discovered that substrate of LACTB can be LACTB itself; that LACTB possesses autoproteolytic ability, which is important for the modulation of its tumor suppressor activity. We show that cancer cells misuse this feature of LACTB to force LACTB into self-degradation. This is mechanistically realized through upregulation of mitochondrial MRPS34 protein, which, through interaction with LACTB, is a positive regulator of the autoproteolytic activity of LACTB and a negative regulator of LACTB. This study, through in vitro, in vivo, human clinical tumor samples and mutagenesis, provides important new insights into how cancer cells fine-tune the expression and activity of tumor suppressors to promote tumorigenesis. Statement of SignificanceWe uncovered a unique post-translational strategy and mechanism cancer cells employ to inactivate the potent mitochondrial tumor suppressor LACTB in breast cancers thus expanding our knowledge on regulatory and adaptive mechanisms cancer cells use to silence tumor suppressors.

cancer biology↗

Genomic Structural Variation Underlies Cell-Type-Specific Betacyanin Variegation in Chenopodium quinoa

The allotetraploid crop quinoa (Chenopodium quinoa) accumulates red/violet betacyanins, which function as vital stress-mitigating antioxidants. We investigated the genetic basis of red/green variegation observed in the aerial organs of the P0429 accession. We demonstrated that this color mosaic is primarily localized to the epidermal bladder cells (EBCs), with red EBCs accumulating [~]50-fold higher betacyanin levels than colorless EBCs. Cell-type-specific RNA-sequencing of EBCs identified the cytochrome P450 gene Cqu0091301 (CYP76AD) as the dominant and rate-limiting factor, exhibiting strong upregulation in red EBCs. This high pigmentation requires a specific structural variation in the P0429 accession: a [~]4-kb genomic insertion that restores the full functionality of Cqu0091301, which is otherwise truncated and non-functional in common reference genomes. Genomic analysis reveals that Cqu0091301 is part of a CYP76AD-DODA gene cluster. Notably, expression analysis revealed functional divergence between the quinoa subgenomes, with B-subgenome CYP76AD genes highly dominant in EBCs, while A-subgenome homologs were preferentially expressed in other tissues. Our results establish a clear link between structural genomic variation and cell-type-specific betalain biosynthesis, providing molecular insight into pigment regulation and subgenome specialization in allotetraploid quinoa.

plant biology↗

Normative modeling of brain morphology reveals neuroanatomical heterogeneity and biological subtypes in major depressive disorder

BACKGROUNDMajor Depressive Disorder (MDD) is characterized by high neurobiological heterogeneity, which hinders precise diagnosis and treatment. Traditional group-level neuroimaging analyses fail to capture individual differences, while normative modeling offer a promising approach to quantify individual deviations from healthy brain structure patterns, facilitating the identification of biological subtypes and offering a data-driven framework to dissect this heterogeneity. METHODSUsing 1,190 healthy controls, we constructed normative developmental trajectories of gray matter volume (GMV) across 246 Brainnetome-defined regions using Bayesian linear regression. Deviation maps were derived for 398 MDD patients. k-means clustering was employed to identify GMV-based biotypes. Then, the clinical characteristics and anatomical differences among these subtypes were explored, along with the post-treatment clinical features and treatment responses of participants who completed the 8-week antidepressant treatment within each subtype. RESULTSPatients with MDD exhibited widespread yet individually variable GMV deviations. Clustering analysis revealed two subtypes: Subtype 1 displayed predominantly negative deviations in sensorimotor and occipital cortices, whereas Subtype 2 showed widespread positive deviations in temporal and posterior cingulate regions. Subtype 1 had higher extraversion and symptom-linked deviation patterns; in Subtype 2, deviation burden correlated with generalized anxiety. Longitudinally, Subtype 1s GMV deviation changes predicted symptom improvement, while Subtype 2s deviations correlated with baseline severity. CONCLUSIONSNormative modeling of GMV reveals marked neuroanatomical heterogeneity in MDD and identifies subtypes with distinct clinical and treatment-related characteristics, laying a foundation for precision psychiatry and individualized interventions.

neuroscience↗

Engineering the citrus phyllosphere microbiome for enhanced disease resistance to bacterial canker

Engineering phyllosphere microbiomes toward plant protection against pathogens on crops has shown promising effects. Here we tested the effect of application of beneficial bacteria individually and as a synthetic community (SynCom) on the phyllosphere microbiome and management of bacterial canker caused by Xanthomonas citri subsp. citri (Xcc). Foliar spray of a SynCom consisting of three citrus endophytic bacterial strains (Paenibacillus sp. ATY16, Bacillus megaterium PT6, and Bacillus subtilis PT26A, SynCom1) with mechanistically complemented plant-beneficial properties exerted a more profound effect on the leaf microbiota and suppression of citrus canker than single strains. Cultivation-dependent and bacterial 16S rRNA gene-sequence profiling analyses revealed that leaf endophytic Bradyrhizobium, Brevibacillus, Cellvibrio, Flavobacterium, and Pseudomonas were significantly enriched in the SynCom treated plants, in addition to Bacillus and Paenibacillus. The enriched Brevibacillus and Pseudomonas spp. were isolated, whole-genome sequenced, and confirmed to possess multiple beneficial traits including antimicrobial activity against Xcc, Moreover, the expression of citrus defense genes was induced by the SynCom1 inoculation. Foliar application of SynCom1 and a newly assembled SynCom (SynCom2; SynCom1 with representative Brevibacillus and Pseudomonas isolates) prior to Xcc inoculation significantly reduced the citrus canker disease severity in greenhouse assays, and SynCom2 had a better efficacy, comparable to a copper bactericide. Three-year field tests showed that both SynCom1 and SynCom2 effectively controlled citrus canker, with a 50% reduction of foliar and fruit canker incidence. Collectively, these findings provide novel insights and valuable clues for microbiome engineering to serve as a sustainable strategy for the control of phyllosphere pathogens on crops.

plant biology↗

Single-Cell Multi-Omics Dissects Transcript Isoform and Immune Repertoire Dynamics in Human Immunosenescence

Immunosenescence, a major hallmark of systemic aging, refers to the progressive functional decline of the immune system. This decline not only compromises host defense and immunological memory but also fuels chronic inflammation and tissue degeneration (collectively known as inflammaging). While single-cell RNA sequencing (scRNA-seq) has revealed transcriptomic alterations in immune aging, analyses restricted to transcript abundance fail to capture deeper regulatory layers, such as transcript isoform diversity and the remodeling of immune receptor repertoires. To address this, we present the human peripheral immune single-cell multi-omics atlas that integrates gene expression, transcript isoforms diversity, and immune receptor repertoires. By combining single-cell full-length transcriptome sequencing (scCycloneSEQ), short-read scRNA-seq, and single-cell immune receptor sequencing (scTCR/BCR-seq), we systematically profiled peripheral blood mononuclear cells (PBMCs) from healthy young and elderly donors. Our analyses uncovered extensive age-related remodeling of immune cell composition, functional states, and TCR/BCR diversity. Notably, we identified in CD4 effector memory T cells exhibited widespread differential isoform usage (DIU), 3'UTR length variation, and a marked reshaping of cytotoxic T lymphocyte (CTL) clonotypes--all closely associated with aging-related inflammation and cellular senescence. This multi-omics atlas delineates key molecular features of immunosenescence and provides a high-resolution resource for deciphering the regulatory architecture underlying immune aging.

immunology↗

Assessing the Influence of Tractography Methods on White Matter Microstructure and Tractometry Analysis in Alzheimer's Disease

Tractometry enables detailed mapping of white matter microstructure along individual tracts and is widely used to study disease effects such as those seen in Alzheimers disease (AD). However, how different tractography algorithms influence tractometry outcomes remains unclear. Here, we compared whole-brain deterministic and probabilistic tractography using the BUndle ANalytics (BUAN) framework in the Alzheimers Disease Neuroimaging Initiative (ADNI) dataset, including 118 AD and 728 cognitively normal (CN) participants. Both approaches revealed the expected pattern of lower fractional anisotropy (FA) and higher mean, radial, and axial diffusivity (MD, RD, AxD) in AD, consistent with white matter degeneration. Despite broadly similar global trends, substantial bundle-level differences emerged between the two tractography methods. Probabilistic tracking produced stronger and more spatially extended effects in the fornix, a small and highly curved limbic pathway vulnerable to AD-related degeneration, whereas deterministic tracking showed greater sensitivity in the posterior segments of the right superior longitudinal fasciculus (SLF R). These discrepancies highlight that the choice of tractography algorithm can alter detecting disease effects, emphasizing the need for cross-method validation to ensure the robustness and interpretability of along-tract measures.

neuroscience↗

Evaluating Sample-Size Efficiency and Sensitivity of Tractometry in Alzheimer's Disease

Tractometry allows quantitative analysis of white matter microstructure along the brains fiber tracts, but the impact of study design parameters--such as sample size and along-tract resolution--on sensitivity and specificity is not well understood. In this study, we conducted tractometry bootstrap analysis using linear-mixed models across four diffusion tensor imaging (DTI) metrics to systematically evaluate how these factors affect the detection of dementia- and amyloidrelated effects. While coarser along-tract segments yield greater sensitivity and higher mean effect sizes, finer segments tend to produce higher peak effect sizes, revealing more spatially localized effects. Dementia-related effects were more widespread and detectable with fewer subjects, whereas amyloid-related effects were more subtle and localized, requiring larger cohorts to detect them. These findings highlight that tractometry offers improved spatial specificity and can reliably detect small, fine-scale effects, but study design should be tailored to specific research questions, considering the expected spatial extent and magnitude of effects, to optimize sample size efficiency and interpretability.

neuroscience↗