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Biology subjects

Lu, Z.

Publications and source records attributed to Lu, Z..

At least 109 records · Page 6Linked to original sources

Data Release: High-Resolution Imaging and Segmentation of P7 Mouse Tissue Microarchitecture Using FIB-SEM and Machine Learning

This report presents a comprehensive data release exploring the tissue microarchitecture of P7 aged mice using Focused Ion Beam Scanning Electron Microscopy (FIB-SEM) combined with machine learning-based segmentations of nuclei. The study includes high-resolution 3D volumes and nucleus segmentations for seven vital tissues--pancreas, liver, kidney, heart, thymus, hippocampus, and skin--from a single mouse. The detailed datasets are openly accessible onOpenOrganelle.org, providing a valuable resource for the scientific community to support further research and collaboration.

cell biology↗

Proteome structuring of crown-of-thorns starfish

This data report presents the proteome structuring of the crown-of-thorns starfish (COTS, Acanthaster planci) using the ColabFold system. The resulting dataset includes 31,743 predicted protein structures, covering 60.4% of residues with confident predictions and 35.5% with very high confidence. A preliminary structural bioinformatics analysis was conducted using post-AlphaFold methods, including fast structure clustering, ligand transplanting, and structure-based Gene Ontology (GO) annotation, which identified potential functions for previously uncharacterized proteins. These findings contribute to a deeper understanding of COTS biology and provide valuable data for developing biocontrol methods to mitigate the impact of COTS outbreaks on coral reefs.

bioinformatics↗

Single-cell analysis of the somatic mutational landscape in human chondrocytes during aging and in osteoarthritis

Somatic mutation is now recognized as a cause of multiple human diseases other than cancer. Osteoarthritis (OA), a highly prevalent age-related disease, has been associated with increased chromosomal abnormalities in articular cartilage of OA patients. Thus far no systematic attempt has been made to characterize the somatic mutational landscape of chondrocytes during normal aging and in affected cartilage of OA patients. Here we used single-cell whole genome sequencing to quantitatively analyze single-nucleotide variants (SNVs) and small insertions and deletions (InDels) in 100 single chondrocytes isolated from the cartilage of hip femoral heads of 17 subjects aged from 26 to 90 years, including 9 OA patients and 8 non-OA donors. Both SNVs and InDels were found to accumulate with age in chondrocytes with a clock-like mutational signature. Surprisingly, the age-related accumulation rate of these mutations was found to be lower in OA chondrocytes compared with chondrocytes from non-OA control subjects.

genomics↗

Negatively Charged alpha-Synuclein Condensate Modulates Partitioning of Molecules

-Synuclein (Syn) aggregation via liquid-liquid phase separation has recently emerged as a crucial mechanism underlying amyloid fibril formation implicated in Parkinsons disease. However, comprehensive investigations of the physico-chemical properties of Syn condensate remains incomplete. Here, we showed that Syn condensate possesses a highly negative electrostatic potential that spans the whole condensate. This property causes differential partitioning of dye-labeled Syn as well as fluorescent molecules by an order of magnitude depending on their net charges. Consistent with this, the phase separation propensity of Syn is governed by a delicate balance between self-association of Syn and electrostatic repulsion, hence is antagonized by excess negative charge. We further demonstrated that, in differentiated neuron-like SH-SY5Y cells, Syn also forms negatively charged condensate. Our results highlighted the significant impact of Syn condensates electrostatic potential on molecular partitioning, hence calling for close examination of the electrostatic property of other biomolecular condensates.

biophysics↗

A scene with an invisible wall - navigational experience shapes visual scene representation

Human navigation heavily relies on visual information. Although many previous studies have investigated how navigational information is inferred from visual features of scenes, little is understood about the impact of navigational experience on visual scene representation. In this study, we examined how navigational experience influences both the behavioral and neural responses to a visual scene. During training, participants navigated in the virtual reality (VR) environments which we manipulated navigational experience while holding the visual properties of scenes constant. Half of the environments allowed free navigation (navigable), while the other half featured an invisible wall preventing the participants to continue forward even though the scene was visually navigable (non-navigable). During testing, participants viewed scene images from the VR environment while completing either a behavioral perceptual identification task (Experiment1) or an fMRI scan (Experiment2). Behaviorally, we found that participants judged a scene pair to be significantly more visually different if their prior navigational experience varied, even after accounting for visual similarities between the scene pairs. Neurally, multi-voxel pattern of the parahippocampal place area (PPA) distinguished visual scenes based on prior navigational experience alone. These results suggest that the human visual scene cortex represents information about navigability obtained through prior experience, beyond those computable from the visual properties of the scene. Taken together, these results suggest that scene representation is modulated by prior navigational experience to help us construct a functionally meaningful visual environment.

neuroscience↗

A smartphone-based genetically recombinant whole-cell biosensor for highly sensitive monitoring of polychlorinated biphenyls (PCBs)

Polychlorinated biphenyls (PCBs) are highly carcinogenic and persistent pollutants commonly found in ecosystems. Their complex congeners pose a huge challenge to instrumental analysis and ELISA methods, which prefer single and known targets. To overcome this limitation, here we developed an Escherichia coli whole-cell biosensor (WCB) for simultaneously detecting multiple PCB congeners. In this sensor, PCBs were firstly converted into hydroxylated PCBs (OH-PCBs) by bphAB degradation circuits, which then serve as high-affinity targets of transcriptional factor HbpRCBP6-based sensing pathways for sensitive response through extensive chassis screening. The resulting biosensor BL21(DE3)/HbpRCBP6-bphAB shows the lowest detection limits for 2-CBP (2-chlorobiphenyl) to date and can recognize various PCB homologues, including 3-CBP, 4-CBP, 2,3-diCBP and 2,2-diCBP, with detection limits of 0.06-1 M. Further investigation of the docking structure and binding energy reveal that HbpRCBP6 has a stronger affinity for OH-PCBs than for PCBs, indicating that the conversion of PCB by BphAB enzymes is a key step to improve the sensitivity of WCB. Subsequently, we developed an immobilized hydrogel WCB and a smartphone-based detection procedure to facilitate real-time and user-friendly PCB detection. This study will not only advance the biomonitoring of PCB contaminants but also provide an innovative strategy for developing metabolic pathway-sensing proteins combined biosensor. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=128 SRC="FIGDIR/small/601110v1_ufig1.gif" ALT="Figure 1"> View larger version (29K): org.highwire.dtl.DTLVardef@10772cdorg.highwire.dtl.DTLVardef@22699org.highwire.dtl.DTLVardef@1343c27org.highwire.dtl.DTLVardef@595859_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioengineering↗

A new yeast-based bioreporter for simple, sensitive, and cost-effective detection of dioxin-like compounds

Dioxin-like compounds (DLCs) are environmental xenobiotics that can activate the aryl hydrocarbon receptors (AhR), thereby imposing a significant threat to human health through biomagnifications processes. In this study, a dioxin-activated nano-luminescent Saccharomyces cerevisiae bioreporter, called DnaSc, was developed for simple and rapid detection of DLCs and AhR agonists. The bioreporter used nano-luciferase NLuc as a signal generator to emit bioluminescent signals in response to DLCs without cell lysis. Through optimizing ARNT expression and engineering the aryl hydrocarbon receptor (AhR), the yeast-based bioassay exhibited a detection limit of 10 fM for 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) within 6 h, making it the most sensitive whole-cell biosensor reported to date. Furthermore, the detection capacity of the DnaSc bioassay for DLCs and AhR agonists was characterized. In summary, the yeast-based bioreporter developed in this study provided a simple, sensitive, and cost-effective method for DLCs detection.

bioengineering↗

Tracing neurodiverse disruptions underlying emotional episodic memory to diagnosis-specific network of emotional regulation in psychiatric disorders

BackgroundAffective symptoms are a prevalent psychopathological feature in various psychiatric disorders. However, the underlying neurobiological mechanisms are complex and not yet fully understood. MethodsWe used normative modelling to establish a reference for neurofunctional activation of functional magnetic resonance imaging based on an emotional episodic memory task, which is frequently used to study affective symptoms in psychiatric disorders. This normative reference was derived from a large dataset of healthy individuals (n = 409), and used to evaluate individualized functional alterations by calculating deviations from this reference in a clinical dataset of 328 participants, which included 168 healthy controls and patients with major depressive disorder (MDD, n = 56), bipolar disorder (BD, n = 31), and schizophrenia (SZ, n = 73). The neurofunctional deviations were mapped to emotional networks with specific emotional functions and used to predict affective symptoms in different mental disorders. The microscale cellular signatures underlying macroscale variations were identified using imaging transcriptomic analysis, and associated with affective symptoms. ResultsWe observed distinct patterns of cross-scale neural alterations linked to affective symptoms in three psychiatric disorders. Macroscale neural dysfunctions in distinct disorders were embedded into non-overlapping emotional networks and significantly associated with affective symptoms. The oligodendrocytes may mediate the network-specific impairments, and microglia for MDD, astrocytes for BD, and excitatory neurons for SZ as replicable cell-type correlates of affective symptoms. ConclusionsThese findings have potential implications for the understanding of unique neuropathological patterns of affective symptoms in distinct psychiatric disorders and improving individualized treatment response.

neuroscience↗

Discovery of a Heparan-Sulfate Binding Domain in Monkeypox Virus H3 Protein as a New Anti-poxviral Drug Target

Viral adhesion to host cells is a critical step in infection for many viruses, including monkeypox virus (MPXV). In MPXV, the H3 protein mediates viral adhesion through its interaction with heparan sulfate (HS), yet the structural details of this interaction have remained elusive. Using AI-based structural prediction tools and molecular dynamics (MD) simulations, we identified a novel, positively charged -helical domain in H3 that is essential for HS binding. This conserved domain, found across orthopoxviruses, was experimentally validated and shown to be critical for viral adhesion, making it an ideal target for antiviral drug development. Targeting this domain, we designed a protein inhibitor, which disrupted the H3-HS interaction, inhibited viral infection in vitro and viral replication in vivo, offering a promising antiviral candidate. Our findings reveal a novel therapeutic target of MPXV, demonstrating the potential of combination of AI-driven methods and MD simulations to accelerate antiviral drug discovery.

biophysics↗

BIT: Bayesian Identification of Transcriptional Regulators

Transcriptional regulators (TRs) are master controllers of gene expression and play a critical role in both normal tissue development and disease progression. However, existing computational methods for identification of TRs regulating specific biological processes have significant limitations, such as relying on distance on a linear chromosome or binding motifs that have low specificity. Many also use statistical tests in ways that lack interpretability and rigorous confidence measures. We introduce BIT, a novel Bayesian hierarchical model for in-silico TR identification. Leveraging a comprehensive library of TR ChIP-seq data, BIT offers a fully integrated Bayesian approach to assess genome-wide consistency between user-provided epigenomic profiling data and the TR binding library, enabling the identification of critical TRs while quantifying uncertainty. It avoids estimation and inference in a sequential manner or numerous isolated statistical tests, thereby enhancing accuracy and interpretability. BIT successfully identified critical TRs in perturbation experiments, functionally essential TRs in various cancer types, and cell-type-specific TRs within heterogeneous cell populations, offering deeper biological insights into transcriptional regulation.

bioinformatics↗

Skeleton-forming responses of reef-building corals under ocean acidification

Ocean acidification is increasing in frequency and is considered one of the most important causes of severe damage to global coral reefs. Therefore, there is an urgent need to study the impact of acid stress on the growth patterns of major reef-building corals. Here, we studied the skeleton forming strategies of four widely distributed coral species in a simulated acidified habitat with a pH of 7.6-7.8. We reconstructed and visualized the skeleton building process, quantified elemental calcium loss, and determined gene expression changes. The results suggest that different reef-building corals have diverse growing strategies in acidified seawater. A unique cavity-like forming process starts from the inside of the skeletons of Acropora muricata, which sacrifices skeleton density to protect its polyp-canal system. The forming patterns in Pocillopora damicornis, Montipora capricornis, and M. foliosa were characterized by osteoporosis, exhibiting disordered skeletal structures, insufficient synthesis of adhesion proteins, and low bone mass, correspondingly. In addition, we found that skeletal areas near coral polyps suffered less and had later acidified damage than other skeletal areas in the colony. These results help to understand the skeleton-forming strategies of several major coral species under acid stress, thereby laying a foundation for coral reef protection and restoration under increasing ocean acidification.

ecology↗

Rtf1 HMD domain facilitates global histone H2B monoubiquitination and regulates morphogenesis and virulence in the meningitis-causing pathogen Cryptococcus neoformans

Rtf1 is generally considered to be a subunit of the Paf1 complex (Paf1C), which is a multifunctional protein complex involved in histone modification and RNA biosynthesis at multiple stages. Rtf1 is stably associated with the Paf1C in Saccharomyces cerevisiae, but not in other species including humans. Little is known about its function in human fungal pathogens. Here, we show that Rtf1 is required for facilitating H2B monoubiquitination (H2Bub1), and regulates fungal morphogenesis and pathogenicity in the meningitis-causing fungal pathogen Cryptococcus neoformans. Rtf1 is not tightly associated with the Paf1C, and its histone modification domain (HMD) is sufficient to promote H2Bub1 and the expression of genes related to fungal mating and filamentation. Moreover, Rtf1 HMD fully restores fungal morphogenesis and pathogenicity; however, it fails to restore defects of thermal tolerance and melanin production in the rtf1{Delta} strain background. The present study establishes a role for cryptococcal Rtf1 as a Paf1C-independent regulator in regulating fungal morphogenesis and pathogenicity, and highlights the function of HMD in facilitating global H2Bub1 in C. neoformans.

molecular biology↗

Single-cell phylodynamic inference of tissue development and tumor evolution with scPhyloX

Phylodynamics inference (PI) is a powerful approach for quantifying population dynamics and evolutionary trajectories of natural species based on phylogenetic trees. The emergence of single-cell lineage tracing technologies now enables the reconstruction of phylogenetic trees for thousands of individual cells within a multicellular organism, opening avenues for employing PI methodologies at the cellular level. However, the intricate process of cell differentiation poses challenges for directly applying current PI frameworks in somatic tissues. Here, we introduce a novel computational approach called single-cell phylodynamic explorer (scPhyloX), designed to model structured cell populations in various cell states, by leveraging single-cell phylogenetic trees to infer dynamics of tissue development and tumor evolution. Our comprehensive simulations demonstrate the high accuracy of scPhyloX across various biological scenarios. Application of scPhyloX to three real datasets of single-cell lineage tracing unveils novel insights into somatic dynamics, such as the overshoot of cycling stem cell populations in fly organ development, clonal expansion of multipotent progenitors of hematopoiesis during human aging, and pronounced subclonal selection in early colorectal tumorigenesis. Thus, scPhyloX is an innovative computational method for investigating the development and evolution of somatic tissues.

bioinformatics↗

Unveiling the molecular choreography: In-depth single-cell transcriptomic exploration of the regenerative dynamics in stony coral

The coral reef ecosystem faces increasing threats under global climate challenges. One of the core issues is the inability of fragments to quickly grow into a size that can resist environmental pressures in coral transplantation. The observation of accelerated growth during the early stages of coral regeneration provides new insights for addressing this challenge. To investigate related molecular mechanisms, our study focused on the fast-growing stony coral Acropora muricata (with chromosome-scale reference genome). Employing diverse techniques, including single-cell RNA sequencing (scRNA-seq), we unveiled related intricate cellular dynamics. Single-cell analysis revealed notable shifts in calicoblasts and epidermal cells around 2-4 weeks post-injury. Gene expression analysis revealed enrichment in immune response and biomineralization pathways. Pseudotime analysis explained the differentiation of epidermal cells into calicoblasts, while time-course analysis identified key genes associated with dynamic biomineralization changes. This study enhances our understanding of coral regeneration, offering insights for protective strategies to foster coral growth.

molecular biology↗

Linkage: an interactive shiny app and R package for linking of DNA regulatory peaks to genes

SummaryExisting studies have demonstrated that the integration analysis of transcriptomic and epigenomic data can be used to better understand the onset and progression of many diseases, as well as identify new diagnostic and prognostic biomarkers. However, such investigations on large-scale sequencing data remain challenging for researchers or clinicians with limited bioinformatics knowledge. To facilitate the interpretation of gene regulatory landscape, we developed an R Shiny application and R package [Linking of atac-seq to gene expression data (Linkage)] for exploring and visualizing potential cis-regulatory elements (CREs) of genes based on ATAC-seq and RNA-seq data. Linkage offers six modules to systematically identify, annotate, and interpret potential gene regulatory elements from the whole genome step by step. Linkage can provide interactive visualization for the correlation between chromatin accessibility and gene expression. More than that, Linkage identifies transcription factors (TFs) that potentially drive the chromatin changes through identifying TF binding motifs within the CREs and constructing trans-regulatory networks of the target gene set. This powerful tool enables researchers to conduct extensive multiomics integration analysis and generate visually appealing visualizations that effectively highlight the relationship between genes and corresponding regulatory elements. With Linkage, users can obtain publishable results and gain deeper insights into the gene regulatory landscape. Availability and implementation Linkage is freely available as a Shiny web application (https://xulabgdpu.org.cn/linkage) and an R package (https://github.com/XuLab-GDPU/Linkage). The documentation is available at (https://aicplane.github.io/Linkage-tutorial/).

bioinformatics↗

Neural compass in the human brain during naturalistic virtual navigation

A central component of wayfinding is the ability to maintain a consistent representation of ones facing direction when moving about the world. In rodents, head direction cells are believed to support this "neural compass", but identifying a similar mechanism in humans during dynamic naturalistic navigation has been challenging. To address this issue, we acquired fMRI data while participants freely navigated through a virtual reality city. Encoding model analyses revealed voxel clusters in retrosplenial complex and superior parietal lobule that exhibited reliable tuning as a function of facing direction. Crucially, these directional tunings were consistent across perceptually different versions of the city, spatially separated locations within the city, and motivationally distinct phases of the behavioral task. Analysis of the model weights indicated that these regions may represent facing direction relative to the principal axis of the environment. These findings reveal specific mechanisms in the human brain that allow us to maintain a sense of direction during naturalistic, dynamic navigation.

neuroscience↗

Connectome-driven neural inventory of a complete visual system

Vision provides animals with detailed information about their surroundings, conveying diverse features such as color, form, and movement across the visual scene. Computing these parallel spatial features requires a large and diverse network of neurons, such that in animals as distant as flies and humans, visual regions comprise half the brains volume. These visual brain regions often reveal remarkable structure-function relationships, with neurons organized along spatial maps with shapes that directly relate to their roles in visual processing. To unravel the stunning diversity of a complex visual system, a careful mapping of the neural architecture matched to tools for targeted exploration of that circuitry is essential. Here, we report a new connectome of the right optic lobe from a male Drosophila central nervous system FIB-SEM volume and a comprehensive inventory of the flys visual neurons. We developed a computational framework to quantify the anatomy of visual neurons, establishing a basis for interpreting how their shapes relate to spatial vision. By integrating this analysis with connectivity information, neurotransmitter identity, and expert curation, we classified the [~]53,000 neurons into 727 types, about half of which are systematically described and named for the first time. Finally, we share an extensive collection of split-GAL4 lines matched to our neuron type catalog. Together, this comprehensive set of tools and data unlock new possibilities for systematic investigations of vision in Drosophila, a foundation for a deeper understanding of sensory processing.

neuroscience↗

Cyanamide-inducible expression of homing nuclease I-SceI for iterative genome engineering and parallel promoter characterisation in Saccharomyces cerevisiae

In synthetic biology, microbial chasses including yeast Saccharomyces cerevisiae are iteratively engineered with increasing complexity and scale. Wet-lab genetic engineering tools are developed and optimised to facilitate strain construction but are often incompatible with each other due to shared regulatory elements, such as the galactose-inducible (GAL) promoter in S. cerevisiae. Here, we prototyped the cyanamide-induced I-SceI-mediated double-strand DNA breaks (DSBs) for selectable marker recycling in yeast metabolic engineering. We further combined cyanamide-induced I-SceI-mediated DSB and maltose-induced MazF-mediated negative selection for plasmid-free in situ promoter replacement, which simplified the molecular cloning procedure for promoter characterisation in S. cerevisiae. We then characterised three tetracycline-inducible promoters of differential strength, a non-leaky {beta}-estradiol-inducible promoter, cyanamide-inducible DDI2 promoter, bidirectional MAL32/MAL31 promoters, and five pairs of bidirectional GAL1/GAL10 promoters. Overall, alternative regulatory controls for genome engineering tools are important for the construction of complexed genotypes in microbial systems for synthetic biology and metabolic engineering applications.

synthetic biology↗