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Lu, Z.

Publications and source records attributed to Lu, Z..

At least 91 records · Page 5Linked to original sources

Organism-wide cellular dynamics and epigenomic remodeling in mammalian aging

To investigate organism-wide cellular alterations and epigenomic dynamics during aging, we constructed a single-cell chromatin accessibility atlas spanning 21 mouse tissues across three age groups and both sexes. We found that around one quarter of 536 organ-specific cell types and 1,828 finer-grained subtypes exhibited significant age-related population shifts. Cellular states from broadly distributed lineages displayed synchronized dynamics with age, indicating systemic signals that coordinate these changes. Molecular analyses identified both intrinsic regulators (chromatin peaks, transcription factor activity) and extrinsic factors (cytokine programs) underlying these shifts. Moreover, [~]40% of aging-associated population dynamics were sex-dependent, with tens of thousands of peaks altered exclusively in one sex. Together, these findings present a comprehensive framework for how aging reshapes the chromatin landscape and cellular composition across diverse tissues.

genomics↗

CRIS: A Centralized Resource for High-Quality RNA Structure and Interaction Data in the AI Era

As interest in RNA-based therapeutics expands, there is a growing demand for RNA structure elucidation and RNA-RNA interactions in both academic and clinical settings. Despite rapid advances in methods for RNA structure determination, the field faces persistent challenges in data reproducibility, quality control, and accessibility, largely due to inconsistencies in data processing and analysis workflows. Concurrently, methodological improvements have generated increasingly complex datasets, which necessitate a standardized framework. Here, we present the Crosslinking-based RNA Interactomes and Structuromes (CRIS) database, a comprehensive resource designed to address these limitations. Among existing experimental and computational approaches for RNA structure characterization, crosslinking-based technologies offer superior reliability, high throughput, and high resolution. CRIS provides rigorously curated datasets, standardized workflows, and user-friendly tools, together with built-in quality metrics and detailed visualization guidance to ensure reproducibility and transparency while pairing seamlessly with existing experimental pipelines. By delivering high-complexity RNA datasets alongside accessible computational tools, CRIS serves as a standardized reference for both new and existing data, facilitating investigation through comparative analyses and providing a training resource for deep learning-based computational exploration. This will enable integration into machine learning workflows for large scale, novel RNA structure discovery.

bioinformatics↗

EnrichSci: Transcript-guided Targeted Cell Enrichment for Scalable Single-Cell RNA Sequencing

Large-scale single-cell atlas efforts have revealed many aging-or disease-associated cell types, yet these populations are often underrepresented in heterogeneous tissues, limiting detailed molecular and dynamic analyses. To address this, we developed EnrichSci--a highly scalable, microfluidics-free platform that combines Hybridization Chain Reaction RNA FISH with combinatorial indexing to profile single -nucleus transcriptomes of targeted cell types with full gene-body coverage. When applied to profile oligodendrocytes in the aging mouse brain, EnrichSci uncovered aging-associated molecular dynamics across distinct oligodendrocyte subtypes, revealing both shared and subtype-specific gene expression changes. Additionally, we identified aging-associated exon-level signatures that are missed by conventional gene-level analyses, highlighting post-transcriptional regulation as a critical dimension of cell-state dynamics in aging. By coupling transcript-guided enrichment with a scalable sequencing workflow, EnrichSci provides a versatile approach to decode dynamic regulatory landscapes in diverse cell types from complex tissues.

genomics↗

Uncovering Convergent Cell State Dynamics Across Divergent Genetic Perturbations Through Single-Cell High-Content CRISPR Screening

High-throughput genomic studies have uncovered associations between diverse genetic alterations and disease phenotypes; however, elucidating how perturbations in functionally disparate genes give rise to convergent cellular states remains challenging. Here, we present PerturbFate, a high-throughput, cost-effective, combinatorial-indexing single-cell platform that enables systematic interrogation of massively parallel CRISPR perturbations across the full spectrum of gene regulation, from chromatin remodeling and nascent transcription to steady-state transcriptomic phenotypes. Using PerturbFate, we profiled over 300,000 cultured melanoma cells to characterize multi-modal phenotypic and gene regulatory responses to perturbations in more than 140 Vemurafenib resistance-associated genes. We uncovered a shared dedifferentiated cell state marked by convergent transcription factor (TF) activity signatures across diverse genetic perturbations. Combined inhibition of cooperative TF hubs effectively reversed cellular adaptation to Vemurafenib treatment. We further dissected phenotypic responses to perturbations in Mediator Complex components, linking module-specific biochemical properties to convergent gene activations. Together, we reveal common regulatory nodes that drive similar phenotypic outcomes across distinct genetic perturbations. We also delineate how perturbations in functionally unrelated genes reshape cell state. PerturbFate thus establishes a versatile platform for identifying key molecular regulators by anchoring multi-modal regulatory dynamics to disease-relevant phenotypes.

genomics↗

Leveraging mRNA platform for the development of vaccines against egg allergy

Food allergy has posed a major global health burden due to the rising prevalence and lack of effective prophylactic strategies. During the past decades, allergen-specific immunotherapy (AIT) has been used as a disease-modifying therapy for food allergic conditions, but due to the long-term treatment duration, poor patient compliance and unexpected adverse reactions, only a minority of patients benefit from AIT therapy. In this proof-of-concept study, using well-established mRNA platform, we developed mRNA vaccine candidates encoding for the major egg white allergen Gal d2 (also known as ovalbumin) and comprehensively evaluated the prophylactic efficacy against anaphylaxis in a Gal d2-induced allergic mouse model. Two vaccine formulations, Gal d2 mRNA vaccine and Gal d2-IL-10 mRNA vaccine, both demonstrated effective ability in preventing the onset of allergic disease, which is largely attributed to the versatilities of mRNA vaccine in eliciting allergen-blocking antibody, shifting Th2 towards Th1 immunity, as well as in generating peripheral tolerance.

immunology↗

AI-Guided Precision in Antibody Humanization: Structural Modeling to Minimize Immunogenicity and Preserve Efficacy

Antibody humanization is an essential part of converting animal-derived antibodies into clinical candidates however conventional CDR grafting techniques often faces challenges, especially when essential antigen-binding sites extend beyond CDR regions. Additionally, the CDR grafting process tends to retain undesired non-human elements within the CDR regions. In this study, we overcame these challenges by using our proprietary AI-predicted antigen-antibody complex algorithm to effectively humanize a murine antibody. During our AI-powered humanization process, in contrast to traditional CDR grafting techniques, only the crucial paratopes identified through our AI-predicted complex structure were precision grafted onto a select human germline. This paratope grafting technique significantly reduced the antibodies immunogenicity risk while maintaining bioactivity. Moreover, all AI-guided deep humanized antibody variants demonstrated favorable developability, including thermal stability, poly-reactivity, and hydrophobicity. These results not only advance antibody humanization techniques but also demonstrate the power of AI in expediting antibody engineering and derisking clinical research.

bioengineering↗

Isolated Configuration: Holistic Processing Beyond the Realm of Faces

Holistic processing of visual stimuli has long been regarded as unique to faces, or otherwise extended to other object categories given sufficient expertise. We designed novel abstract stimuli that are recognizable strictly by configural information, and matched control stimuli that require the use of only featural information. We then tested four classic markers of holistic perception: inversion, misalignment, part-whole, and composite effects. We found that second-order configuration stimuli elicited robust holistic effects, while featural stimuli do not, showing that such effects emerge specifically when recognition depends on configural information, but not when it relies on featural cues. We further observed that first-order configuration stimuli were also sufficient to induce holistic effects, indicating that holistic processing can emerge from multiple levels of configural information. We also found a significant correlation between individual differences in face recognition ability and holistic processing effects with the second-order configuration stimuli, but not with the first order configuration stimuli, nor the featural stimuli. Lastly, convolutional neural networks trained on the same stimuli reproduced these patterns, strengthening the interpretation that holistic processing arises when configural information must be used to recognize a stimulus. Together, these findings demonstrate that holistic processing is fundamentally rooted in the representation of spatial configuration, with second-order relations providing the critical link to face recognition ability.

neuroscience↗

GFHunter enables accurate and efficient gene fusion detection in long-read cancer transcriptomes

The precise identification of gene fusions is crucial for cancer diagnosis and therapeutic decision-making. Long-read transcriptome sequencing provides distinct advantages over short-read technologies by capturing full-length fusion gene structures. However, fully harnessing long-read data for cancer research necessitates advanced computational approaches. In this study, we present GFHunter, a novel computational framework designed for efficient and accurate gene fusion detection. Benchmarking on both simulated and real long-read transcriptome datasets from non-tumor and cancer cell lines demonstrates that GFHunter accurately detects gene fusions with high sensitivity and significantly reduces false positives. Additionally, GFHunter runs 2-3 times faster and requires only 16%-50% of the memory compared to state-of-the-art tools. Notably, GFHunter uniquely identifies two known cancer-related fusions in HCT-116 and SKBR-3 cancer cell lines. These results highlight GFHunters potential as a powerful tool for advancing precision oncology and molecular diagnostics.

bioinformatics↗

A pan-gene catalogue of Asian cultivated rice

The rice genome underpins fundamental research and breeding, but the Nipponbare (japonica) reference does not fully encompass the genetic diversity of Asian rice. To address this gap, the Rice Population Reference Panel (RPRP) was developed, comprising high-quality assemblies of 16 rice cultivars to represent japonica, indica, aus, and aromatic varietal groups. The RPRP has been consistently annotated, supported by extensive experimental data and here we report the computational assignment, characterization and dissemination of stably identified pan-genes. We identified 25,178 core pan-genes shared across all cultivars, alongside cultivar-specific and family-enriched genes. Core genes exhibit higher gene expression and proteomic evidence, higher confidence protein domains and AlphaFold structures, while cultivar-specific genes were enriched for domains under selective breeding pressure, such as for disease resistance. This resource, integrated into public databases, enables researchers to explore genetic and functional diversity via a population-aware "reference guide" across rice genomes, advancing both basic and applied research.

genomics↗

Kidney cortex macrophages prevent the formation of mineral stones by reabsorbing phosphate from the urine

Resident macrophages are important in maintaining tissue homeostasis by meeting specialized physiological demands and mitigating the unique stresses each tissue endures. In the kidney, urine is formed in a process of glomerular filtration and tubular reabsorption. Supersaturation of mineral solutes such as calcium phosphate poses a persistent challenge to the kidney; if left unchecked, kidneys stones form, which will cause tubular obstruction and even kidney failure. However, cellular mechanisms of preventing kidney stone formation remain incompletely understood. In this study, we found that resident macrophages in kidney cortex distinguishably expressed phosphate transporter SLC34A1. These cells extend transtubular protrusions and were capable of reabsorbing phosphate from the urine through the SLC34A1, a function previously only attributed to tubular epithelial cells. Depletion of Slc34a1 from kidney cortex macrophages led to increased urinary phosphate excretion, disrupting body phosphorus balance. More importantly, loss of macrophage-mediated phosphate reabsorption from the urine resulted in a drastic over-deposition of calcium phosphate microcrystals in kidney tubules, particularly in the late proximal tubules of inner cortex where intratubular calcium concentration is high. This also accelerated mineral stone formation. Exposure to mineral crystals stimulated cortex macrophages to upregulate SLC34A1 expression, a response mechanistically driven by lysosomal disruption. As such, cortex macrophages employed phosphate reabsorption as a proactive strategy to prevent mineral stone formation.

immunology↗

Unsupervised multi-animal tracking for quantitative ethology

Quantitative ethology necessitates accurate tracking of animal locomotion, especially for population-level analyses involving multiple individuals. However, current methods rely on laborious annotations for supervised training and have restricted performance in challenging conditions. Here we present an unsupervised deep-learning method for multi-animal tracking (UDMT) that achieves state-of-the-art performance without requiring human annotations. By synergizing a bidirectional closed-loop tracking strategy, a spatiotemporal transformer network, and three sophisticatedly designed modules for localization refining, bidirectional ID correction, and automatic parameter tuning, UDMT can track multiple animals accurately in various challenging conditions, such as crowding, occlusion, rapid motion, low contrast, and cross-species experiments. We demonstrate the versatility of UDMT on five different kinds of model animals, including mice, rats, Drosophila, C. elegans, and Betta splendens. Combined with a head-mounted miniaturized microscope, we illustrate the power of UDMT for neuroethological interrogations to decipher the correlations between animal locomotion and neural activity. UDMT will facilitate advancements in ethology by providing a high-performance, annotation-free, and accessible tool for multi-animal tracking.

animal behavior and cognition↗

Spacer Extension Reconciles Specificity and Activity in High-Fidelity Cas9 Genome Editing

AbstractEngineering high-fidelity CRISPR enzymes often leads to reduced cleavage activity, creating a significant hurdle in balancing nuclease specificity and efficiency for clinical applications. Here, we demonstrate that extending the spacer to 21 or 22 nucleotides restores the impaired cleavage activity of SuperFi-Cas9, an engineered high-fidelity Cas9 variant with seven mutations at the PAM-distal region. Structural and mutational analyses reveal that the spacer extension strengthens additional interactions at the PAM-distal end, stabilizing the nuclease- sgRNA-DNA complex, which appears to be disturbed due to the seven mutations. This approach not only provides a high-fidelity Cas9 with uncompromised efficiency but also introduces a novel strategy to enhance CRISPR complex stability. Our findings offer a promising avenue for precise and efficient genome editing, crucial for advancing CRISPR technologies toward clinical translation.

genomics↗

Tissue-resident skeletal muscle macrophages promote recovery from viral pneumonia-induced sarcopenia in normal aging.

Sarcopenia, which diminishes lifespan and healthspan in the elderly, is commonly exacerbated by viral pneumonia, including influenza and COVID-19. In a study of influenza A pneumonia in mice, young mice fully recovered from sarcopenia, while older mice did not. We identified a population of tissue-resident skeletal muscle macrophages that form a spatial niche with satellite cells and myofibers in young mice but are lost with age. Mice with a gain-of-function mutation in the Mertk receptor maintained this macrophage-myofiber interaction during aging and fully recovered from influenza-induced sarcopenia. In contrast, deletion of Mertk in macrophages or loss of Cx3cr1 disrupted this niche, preventing muscle regeneration. Heterochronic parabiosis did not restore the niche in old mice. These findings suggest that age-related loss of Mertk in muscle tissue-resident macrophages disrupts the cellular signaling necessary for muscle regeneration after viral pneumonia, offering a potential target to mitigate sarcopenia in aging.

immunology↗

Integrative analysis of transcriptome and metabolism reveals functional roles of redox homeostasis in low light and salt combined stress in Leymus chinensis

Soil salinity (Salt) is one of the major limiting factors of Leymus chinensis (named sheepgrass) performance and alters their primary metabolic process and gene expression. Salt stress could accelerate inhibitive effects concomitant with low light (LL-Salt). However, little is known about physiological and molecular mechanisms under such LL-Salt in sheepgrass. This study aims to uncover the key reprogrammed metabolic pathways induced by LL-Salt through an integrated analysis of transcriptome and metabolism. Plant seedlings were exposed to six combinations of light intensity (moderate light, ML, and LL) and NaCl concentrations (0, 50, and 200mM) for 20 days. Results suggest that the growth of sheepgrass seedlings was dramatically inhibited with severe lodging phenotype, especially when exposed to LL-Salt combined conditions. Activities of an antioxidant enzyme, catalase, were significantly increased in LL but significantly decreased in salt stress, leading to a reverse pattern for H2O2 in LL and salt stress. Transcriptome analysis reveals 4921 downregulated differentially expressed genes (DEGs) with carbon metabolism pathways were significantly enriched compared to light response without salt (ML_0 vs LL_0). There are 194 overlapped downregulated DEGs induced by two salt treatments (ML_50 vs ML_0 and ML_200 vs ML_0), where the carbon metabolism pathway was also significantly enriched. In terms of interactive effects of LL-Salt treatments, we found that there are 16 overlapped DEGs, including a phytochrome-interacting transcription factor 4 (PIF4) with upregulation in LL treatment while downregulation in salt treatment, which was validated by qPCR. Metabolism analysis confirmed that in carbon metabolism, the contents of seven differentially abundant metabolites (DAMs), including sucrose, were all downregulated in both LL and salt treatment. In contrast, serine and glycolate in the photorespiration pathway were downregulated in LL while upregulated in salt treatment. A photorespiration regulatory gene, glycolate oxidase expression, was confirmed by qPCR. Collectively, we found that serval antioxidant redox pathways, including photorespiration, GSG/GSSH redox, and ABA signaling, participated in response to LL and salt combined events and highlighted the roles of cellular redox homeostasis in LL-Salt response in sheepgrass.

plant biology↗

Improved split prime editors enable efficient in vivo genome editing

Prime editor (PE) is a precise genome-editing tool that enables all 12 possible base-to-base conversions, as well as insertions and deletions, that does not require DSBs or donor DNA. The efficient delivery of prime editors in vivo is critical for realizing the full potential of prime editing in disease modeling and therapeutic correction. Although PE has been divided into two halves and delivered using dual adeno-associated viruses (AAVs), editing efficiency at different gene loci varies among split sites, and efficient split sites within Cas9 nickase are limited. In this study, by screening multiple split sites, we demonstrated that 1115 (Asn) is an efficient split site when delivering PE by dual-AAV. Besides, we utilized a feature reported by others recently that RNase could be detached from the Cas9n and designed split sites in the first half of Cas9n. We found that split-PE-367 enabled high prime editing efficiency with Rma intein. To test the editing efficiency in vivo, dual-AAV split-ePE3-367 was packaged in AAV9 and delivered by tail vein injection in mice, achieving 24.4% precise genome editing 4 weeks after injection. Our findings establish an alternative split-PE architecture that could achieve robust gene editing efficiency, facilitating the potential utility both in model organisms and as a therapeutic modality.

genomics↗

Chromatin mimicry by human JC virus

Chronically persistent viruses are integral components of the organismal ecosystem in humans and animals 1 2. Many of these viruses replicate and accumulate within the cell nucleus 3. The nuclear location allows viruses to evade cytoplasmic host viral sensors and promotes viral replication 4. One of the unexplored and puzzling aspects of the viral nuclear lifecycle involves the viruss ability to deal with the physical constraints of nuclear architecture. To replicate and accumulate within the nucleus in large numbers sufficient for infection spreading, DNA viruses need to overcome the spatial limitations imposed by chromatin and the nuclear matrix. We found that one of the most widespread and potentially lethal human viruses, the JC polyomavirus 5, interferes with nuclear heterochromatin to create virus-occupied space. The JC viruss impact on heterochromatin is mediated by the viral nonstructural protein, Agnoprotein (Agno). Agnos interference with heterochromatin is governed by structurally diverse mimics of host epigenetic regulators that facilitate virus-induced chromatin reorganization and a dramatic decline in nuclear stiffness in the infected cells. The JCV epigenetic mimicry is critical for the virus infection, as evident from reduced replication of mimic-mutant viruses. Our data suggest that modulation of nuclear mechanical properties is a novel strategy enabling chronicity of the JC and possibly other nuclear virus infections.

microbiology↗

Microglial states determine lesion dynamics in multiple sclerosis

Summary paragraphMultiple sclerosis (MS) is a neuroinflammatory disease of the central nervous system, characterized by demyelinating lesions 1. Lesion expansion contributes to progression and increased disability, while remyelination can recover neurological deficits. However, mechanisms driving lesion dynamics are largely unclear, hindering the development of effective therapeutics. We propose that distinct states of microglia are involved in lesion expansion and remyelination 2,3. Using Stereo-seq, an RNA capture based high-resolution spatial transcriptomics technology with single-cell resolution, on post-mortem human brain tissue, we compared mixed active/inactive lesions with lipid-laden foamy microglia with lesions containing ramified microglia. We identified distinct cellular and molecular mechanisms underlying lesion activity and remyelination, linked to microglia phenotypes and states. Lesions with foamy microglia were characterized by elevated immune activation, increased lymphocyte densities, upregulated immunoglobulin production (IGHG1, IGHG3), increased complement system activity, indication of iron dysregulation (FTL, FTH1), and increased demyelination. In contrast, lesions with ramified microglia exhibited gene expression profiles indicative of myelin stability (ABCA2, QKI) and neuro-axonal protection, fostering an environment conducive to repair and remyelination. Our findings highlight the role of microglial states in lesion expansion and repair in MS and offer promising avenues for the development of therapeutic approaches aimed at preventing MS disability progression.

neuroscience↗

A high-throughput phenotypic screen combined with an ultra-large-scale deep learning-based virtual screening reveals novel scaffolds of antibacterial compounds

The proliferation of multi-drug-resistant bacteria underscores an urgent need for novel antibiotics. Traditional discovery methods face challenges due to limited chemical diversity, high costs, and difficulties in identifying structurally novel compounds. Here, we explore the integration of small molecule high-throughput screening with a deep learning-based virtual screening approach to uncover new antibacterial compounds. Leveraging a diverse library of nearly 2 million small molecules, we conducted comprehensive phenotypic screening against a sensitized Escherichia coli strain that, at a low hit rate, yielded thousands of hits. We trained a deep learning model, GNEprop, to predict antibacterial activity, ensuring robustness through out-of-distribution generalization techniques. Virtual screening of over 1.4 billion compounds identified potential candidates, of which 82 exhibited antibacterial activity, illustrating a 90X improved hit rate over the high-throughput screening experiment GNEprop was trained on. Importantly, a significant portion of these newly identified compounds exhibited high dissimilarity to known antibiotics, indicating promising avenues for further exploration in antibiotic discovery.

bioinformatics↗