Biology subjects

Leng, Y.

Publications and source records attributed to Leng, Y..

At least 19 recordsLinked to original sources

bioRxiv2026

Protruding Geometry Provides Potential Homing Sites of Circulating Tumor Cells

Circulating tumor cells (CTCs) must adhere to the vascular endothelium to initiate metastasis, yet the role of vessel wall topography remains unclear. We present an integrated microfluidic platform combining defined protruding geometries, live cell imaging, and controlled perfusion to study CTC homing. Using a multiscale device that reproduces hierarchical vascular branching, we show that CTCs accumulate preferentially at locations with protruded geometry, including bifurcations, sharp corners and positively curved segments. At these hotspots, a viscoelastic, polymer-like network assembles, capturing CTCs and accompanying progressive multicellular aggregation. This network undergoes stretching and elastic recoil even under laminar flow. Mechanistically, knockdown of DSG2 and ITGB3 reduces retention, suggesting a potential anti metastasis strategy targeting molecular mechanical coupling. Computational fluid dynamics simulations indicate that hotspots coincide with pronounced velocity and pressure perturbations. Our experiments identify local geometry as a critical determinant of CTC arrest and provide a platform for studying the physical mechanisms of metastatic homing.

cancer biology↗

bioRxiv2026

Simulating Bead-Tethered Biomolecules: Force-Probe Coupled Steered Molecular Dynamics (fp-SMD) in Optical Tweezers Force Spectroscopy

Interpreting single-molecule force spectroscopy (SMFS) data from optical tweezers with steered molecular dynamics (SMD) is hindered by a severe timescale mismatch: SMD trajectories span nanoseconds to microseconds, while SMFS experiments unfold over milliseconds to seconds, forcing SMD to pull six to nine orders of magnitude faster than experiment and systematically distorting rupture forces, molecular pathways, and kinetic intermediates. We introduce force-probe coupled steered molecular dynamics (fp-SMD), which explicitly propagates the force probe (the optically trapped bead) alongside the biomolecule within a single classical Hamiltonian description of the coupled molecule-linker-bead system. A Predict-Correct Trajectory Propagation (PCTP) scheme resolves the resulting computational bottleneck by decoupling the fast molecular relaxation from the slow, macroscopic bead motion, using metadynamics and transition-state theory to identify the kinetically resolved molecular intermediate reached at each macroscopic time step. On the cholesterol-{beta}-cyclodextrin ({beta}-CD) host-guest complex, fp-SMD reproduces the experimental rupture-force histogram directly at matched conditions, without extrapolation from standard SMD. fp-SMD further resolves how applied force reshapes the molecular escape pathway itself--cholesterol dissociates via a high-angle route at low force and a direct, small-angle route at high force--providing, to our knowledge, the first direct structural evidence for force-induced pathway switching within small host-guest systems believed to underlie catch-slip bond behavior. fp-SMD/PCTP thus offers a general route to simulating force-probe-coupled biomolecular mechanics at experimentally relevant timescales.

biophysics↗

bioRxiv2026

PromptBio: An Agentic Platform for End-to-End Computational Biomedical Research

Modern biomedical research increasingly depends on complex computational analyses, yet translating a scientific question into a reliable workflow still requires substantial technical expertise and manual coordination. PromptBio is a multi-agent AI platform available through a web portal at https://promptbio.ai that addresses this challenge. Through natural-language interaction, its agent harness, PromptGenie, translates a research objective into an inspectable plan, executes the required research and analysis, and adapts subsequent steps as evidence and results emerge. PromptBio integrates reasoning with managed execution while preserving human oversight and a traceable record of the research process. It can apply validated methods, construct custom analyses, and incorporate external workflows, enabling researchers to move beyond fixed pipelines while supporting reproducibility. We evaluate the platform through benchmarks of end-to-end bioinformatics analysis and biomedical deep research, validation of representative omics and machine-learning skills, and a hypothesis-driven regulatory-genomics case study. PromptGenie achieved higher analytical accuracy and stronger evidence retrieval and synthesis than the comparison agents, while the evaluated domain skills produced results consistent with established methods. The case study further demonstrates how PromptBio can integrate human-specific genomic and epigenomic features to investigate cortical development. Together, these findings show that PromptBio can coordinate complex biomedical analyses under researcher oversight, offering an accessible approach for accelerating scientific iteration and transforming research questions into transparent, reusable computational workflows.

bioinformatics↗

bioRxiv2026

False discovery rate control for trustworthy AI-based de novo peptide sequencing

AI-based de novo peptide sequencing predicts peptide sequences from tandem mass spectra, enabling identification beyond predefined databases but leaving prediction reliability difficult to assess, particularly with respect to false discovery rate (FDR). In database search, FDR control is provided by target-decoy competition over a finite search space, whereas de novo predictions are generated in open sequence space and lack naturally matched sequence-level decoys. Here we introduce Counterpart Calibration Theory (CCT), a theory-guided framework that reframes de novo FDR control as a four-group score-ranking and threshold-selection problem over target-side predictions and matched counterpart-side comparators. Implemented in {pi}-NovoQC, CCT provides dual-level FDR control at the peptide-spectrum match and peptide levels. Across models, datasets, instruments and acquisition modes, {pi}-NovoQC achieves stable FDR control while preserving identification yield. In large-scale proteomic applications, {pi}-NovoQC recovers low-abundance in-database peptides missed by database search and provides de novo-supported protein-group and variant evidence.

bioinformatics↗

bioRxiv2026

PromptBio-Bench: Benchmarking LLM-based Bioinformatics Agents for End-to-End Data Analysis

Large language model (LLM)-based agents hold transformative potential for automating bioinformatics workflows; however, systematic evaluations of their capabilities remain limited, hindering a clear assessment of their readiness for real-world application. We introduce PromptBio-Bench, a comprehensive evaluation suite of 244 expert-curated tasks spanning bioinformatics and data science at varied difficulty levels, and an evaluation framework for structured file comparison and scoring against expert reference answer files. Evaluation of three state-of-the-art bioinformatics agents revealed comparable performance between Biomni and ToolsGenie, with all agents showing a marked decline in accuracy as task difficulty increased. As foundation models and agent frameworks continue to evolve, PromptBio-Bench provides a valuable benchmark infrastructure for systematically tracking progress in agentic bioinformatics.

bioinformatics↗

bioRxiv2026

Reproducible Tools and Enhanced Computational Workflows for Batch Effect Evaluation of High-Throughput Data Using BatchQC

Batch effect correction is a common and often necessary step in data analysis to reduce bias due to technical and experimental factors when combining multiple batches of data. The severity of the batch effects dictates the correction strategy; therefore, a careful assessment of each datasets batch effects is necessary. BatchQC is an R package that provides reproducible tools and visualizations for quantitatively and qualitatively addressing batch effects across a broad range of data types. BatchQC integrates with standardized Bioconductor data structures and features an object-oriented design, enabling the application of workflows that can freely evaluate and process data within and outside the package tools. Common batch evaluation methods, along with novel quantitative metrics, help determine the benefits of batch correction for each dataset and enable direct comparisons between methods. Here, we present BatchQC as the first comprehensive batch-correction R package, with independent tools, reproducible workflows, visualization, and novel statistics.

bioinformatics↗

bioRxiv2026

ToolsGenie 2.0: A Scalable and Extensible Multi-Agent System for Bioinformatics Automation

The rapid expansion of biomedical data necessitates efficient bioinformatics tools, yet conventional workflows rely heavily on manual dependencies, hindering scalability and broader adoption. Building on the foundation of ToolsGenie 1.0, we introduce ToolsGenie 2.0, a multi-agent AI framework that automates bioinformatics analyses through natural language queries and file inputs. ToolsGenie 2.0 addresses the growing need for customizable analyses by offering extensibility, reproducibility, improved accuracy, and ease of use. It incorporates a ReAct-based architecture with dual-layer extensibility for sub-agents and specialized tools, along with dynamic Docker image selection for automated, sandboxed, and secure environment management. Rigorous benchmarking shows that ToolsGenie 2.0 achieves 68.6% accuracy on an in-house dataset and 48.3% accuracy on BixBench, demonstrating competitive performance across diverse evaluation settings. These innovations position ToolsGenie 2.0 as a versatile platform for broadening access to bioinformatics in both research and clinical contexts. ToolsGenie 2.0 is available on the PromptBio platform (platform.promptbio.ai).

bioinformatics↗

bioRxiv2025

Simple, Fast and Highly Efficient One-or Two-step Proteomic Preparation Enables Deep Profiling of Microgram-level FF and FFPE Tissues

Large-scale tissue proteomics requires workflows that are efficient, rapid, and repeatable across diverse samples. Herein, we present Simple Workflow for Integrated and Fast Tissue-preparation (SWIFT), which enables complete processing of fresh- frozen (FF) and formalin-fixed, paraffin-embedded (FFPE) tissues in either one- or two-step formats, while maintaining deep proteome coverage with high repeatability from low to microgram-level tissues. For FF tissues, an incubation process integrating lysis, reduction, alkylation, and digestion generates peptide samples directly from tissues in [≤] 1.5 h. For FFPE tissues, concurrent deparaffinization, rehydration, and de- crosslinking is achieved within 0.5 h, followed by one-step peptide preparation. Furthermore, our workflows eliminate desalting and offline cleanup steps, thereby reducing variability and total processing time. Using our methods, we identified up to [~]10,000 protein groups and [~]150,000 peptides across multiple mouse organs on timsTOF Pro. Repeatability was high (pairwise Pearsons r > 0.96 across six experimental replicates), with dynamic ranges spanning 6-7 orders of magnitude. Organ-enriched protein analysis identified functionally distinct proteins unique to each tissue Paired FF and FFPE analyses revealed preservation-induced shifts, with FFPE tissues showing reduced detection of membrane-associated and respiratory proteins, including mitochondrial Complex I. Together, our fast and simplified workflows enable deep tissue proteomics for large-scale clinical and translational studies in a cost- effective and widely-accessible manner.

biochemistry↗

bioRxiv2025

MetaScope: A High-Resolution Framework for Species-Level 16S Metataxonomic Classification

Accurate species-level classification of microbial communities remains a major challenge in microbiome analysis, particularly when using traditional 16S rRNA amplicon sequencing pipelines such as QIIME2 and DADA2. These methods often fail to resolve taxonomy beyond the genus level due to limitations in clustering algorithms and ambiguous marker genes. To address this, we present MetaScope, a modular, R-based software package that reimplements and extends the PathoScope 2.0 framework for high-resolution microbial classification. MetaScope introduces two key innovations: (1) the integration of user-defined or empirical prior weights into the Bayesian read reassignment algorithm to improve abundance estimation, and (2) MetaBlast, a secondary BLAST-based validation module for refining species-level assignments. Benchmarking against mock and clinical datasets demonstrates that MetaScope significantly outperforms QIIME2 and DADA2, achieving up to 93.6% species-level classification accuracy. This translates to offering enhanced resolution for downstream analyses such as ecological diversity metrics. These results highlight MetaScope as a powerful tool for advancing microbial community profiling in both research and clinical settings.

bioinformatics↗

bioRxiv2025

A synaptic mechanism for encoding the learned value of action-derived safety

Motivated behavior is often framed in terms of biologically grounded outcomes, such as food or threat. Yet many motivated actions, like the pursuit of safety or agency, depend on outcomes that lack explicit sensory value and must instead be inferred from experience. Here, we identify a thalamostriatal circuit mechanism by which such internally constructed outcomes acquire motivational value. In mice performing an active avoidance task, neurons in the paraventricular thalamus (PVT) projecting to the nucleus accumbens (NAc) develop a safety-encoding signal that emerges following successful avoidance. This signal is experience-dependent and value-sensitive, diminishing upon devaluation of the instrumental contingency. Selective silencing of the PVT[->]NAc projection at safety onset disrupts avoidance persistence without impairing action-outcome learning, as confirmed by computational modeling of value updating based on prediction error. Mechanistically, PVT input recruits cholinergic interneurons (CINs) to modulate dopamine release and this influence depends on synaptic potentiation mediated by GluA2-lacking AMPA receptor insertion at PVT-CIN synapses. Disrupting this plasticity selectively impairs the avoidance response by blunting the motivational value of safety without affecting acquisition. These findings reveal how thalamic circuits assign value to abstract, internal outcomes, providing a framework for understanding how goals like safety are inferred, stabilized, and rendered behaviorally effective.

neuroscience↗

bioRxiv2025

PromptBio: A Multi-Agent AI Platform for Bioinformatics Data Analysis

PromptBio is a modular AI platform for scalable, reproducible, and user-adaptable bioinformatics analysis, powered by generative AI and natural language interaction. It supports three complementary modes of analysis designed to meet diverse research needs. PromptGenie is a multi-agent system that enables stepwise, human-in-the-loop workflows using prevalidated domain-standard tools. Within PromptGenie, specialized agents--including DataAgent, OmicsAgent, AnalysisAgent, and QAgent--collaborate to manage tasks such as data ingestion, pipeline execution, statistical analysis, and interactive summarization. DiscoverFlow provides integrated, automated workflows for large-scale multi-omics analysis, offering end-to-end execution and streamlined orchestration. ToolsGenie complements these modes by dynamically generating executable bioinformatics code for custom, user-defined analyses, enabling flexibility beyond standardized workflows. PromptGenie and DiscoverFlow leverage a suite of domain-specific tools, including Omics Tools for standardized omics pipelines, Analysis Tools for downstream statistical interpretation, and MLGenie for machine learning and multi-omics modeling. We present the design, capabilities, and validation of these components, highlight their integration into automated and customizable workflows, and discuss extensibility, monitoring, and compliance. PromptBio aims to democratize high-throughput bioinformatics through a large language model-powered, natural language understanding, workflow generation and agent orchestration.

bioinformatics↗

bioRxiv2025

A protective role of REM sleep in the pathological basal ganglia-cortical circuit of Parkinson's disease

Sleep disturbances have been shown to be intimately and bidirectionally related to disease progression across a wide range of neurodegenerative disorders including Parkinsons disease (PD) and Alzheimers disease. However, the precise neurophysiological mechanisms relating abnormal sleep to aberrant daytime network activity that accelerates disease progression has yet to be determined. We collected chronic, multi-night (n=40), intracranial cortico-basal recordings during sleep from a cohort of patients with PD along with paired polysomnography and morning self-reports. This revealed that longer duration (and shorter latency) of rapid eye movement (REM) sleep predicted reduced daytime resting beta (13-30 Hz) activity and cortico-basal functional and effective connectivity, features established to be pathophysiological in PD. Within REM sleep, stronger cortical delta activity specifically predicted reduced pathophysiological cortico-basal neural network features. Additionally, REM delta power significantly predicted greater self-reported morning alertness. These findings highlight a potentially protective role of REM sleep in cortico-basal network health in PD and daytime subjective experience, representing a potential target for closed loop neuromodulation therapies to impact neurodegenerative disease progression.

neuroscience↗

bioRxiv2024

A conserved cell-type gradient across the human mediodorsal and paraventricular thalamus

The mediodorsal thalamus (MD) and adjacent midline nuclei are important for cognition and mental illness, but their cellular composition is not well defined. Using single-nucleus and spatial transcriptomics, we identified a conserved excitatory neuron gradient, with distinct spatial mapping of individual clusters. One end of the gradient was expanded in human MD compared to mice, which may be related to the expansion of granular prefrontal cortex in hominids. Moreover, neurons preferentially mapping onto the parvocellular division MD were associated with genetic risk for schizophrenia and bipolar disorder. Midbrain-derived inhibitory interneurons were enriched in human MD and implicated in genetic risk for major depressive disorder.

neuroscience↗

bioRxiv2023

A barley MLA receptor is targeted by a non-ribosomal peptide effector of the necrotrophic spot blotch fungus for disease susceptibility

The evolutionary history of plant interactions with necrotrophic pathogens that feed on dying host cells and their virulence mechanisms remains fragmentary. We have isolated the barley gene Scs6, which is required for the necrotrophic fungus Bipolaris sorokiniana isolate ND90Pr to cause spot blotch disease. Scs6 is located at the disease resistance gene locus Mildew locus a (Mla) and encodes an intracellular nucleotide-binding leucine-rich repeat receptor (NLR). In transgenic barley, Scs6 is sufficient to confer susceptibility to ND90Pr in accessions naturally lacking the receptor, resulting in infection-associated host cell death. Expression of Scs6 in evolutionarily distant Nicotiana benthamiana reconstitutes a cell death response to an uncharacterized non-ribosomal peptide effector produced by ND90Pr-specific non-ribosomal peptide synthetases (NRPSs) encoded at the VHv1 virulence locus. Our data suggest that the heat-resistant effector directly activates the SCS6 receptor. Scs6 is an allelic variant of functionally diversified Mla resistance genes each conferring strain-specific immunity to barley powdery mildew isolates with a matching proteinaceous pathogen effector. Domain swaps between MLA and SCS6 NLRs and expression of the resulting hybrid proteins in N. benthamiana reveal that the SCS6 leucine-rich repeat domain is a specificity determinant for the NRPS-derived effector to activate the receptor. Scs6 evolved after the divergence of barley from wheat and is maintained in several wild barley populations with an incidence of 8%, suggesting a beneficial function for the host. Evolution of the bona fide immune receptor SCS6 targeted by the NRPS-derived effector was key for the emergence of strain-specific spot blotch disease in domesticated barley.

plant biology↗

bioRxiv2022

Monitoring the intestinal magnetic field with optically pumped atomic magnetometers

Research has shown the potential of magnetoenterography (MENG) for detecting intestinal diseases noninvasively by superconducting quantum interference devices (SQUIDs). Nevertheless, these devices need to operate under a cytogenetic environment maintained by liquid helium. In this paper, we record the intestinal magnetic field of a rabbit with optically pumped magnetometers (OPMs) at room temperature. It demonstrates that the OPM-based system has sufficient sensitivity to measure the intestinal magnetic fields of the rabbit, and can be potentially developed into a cost-effective and flexible MENG system.

physiology↗

bioRxiv2022

Molecular and spatial profiling of the paraventricular nucleus of the thalamus

The paraventricular nucleus of the thalamus (PVT) is known to regulate various cognitive and behavioral processes. However, while functional diversity among PVT circuits has often been linked to cellular differences, the molecular identity and spatial distribution of PVT cell types remains unclear. To address this gap, here we used single nucleus RNA sequencing (snRNA-seq) and identified five molecularly distinct PVT neuronal subtypes. Additionally, multiplex fluorescent in situ hybridization of top marker genes revealed that PVT subtypes are organized by a combination of previously unidentified molecular gradients. Lastly, comparing our dataset with a recently published single-cell sequencing atlas of thalamus yielded novel insight into the PVTs connectivity with cortex, including unexpected innervation of auditory and visual areas. This comparison also revealed that our data contains a largely non-overlapping transcriptomic map of multiple midline thalamic nuclei. Collectively, our findings uncover previously unknown features of the molecular diversity and anatomical organization of the PVT and provide a valuable resource for future investigations.

neuroscience↗

bioRxiv2022

Expanding adult tubular microvessels on stiff substrates with endothelial cells and pericytes from the same tissue

Microvessels are essential for tissue engineering and regeneration. In current methods, endothelial cells are usually cultured in commercially available media and form a monolayer of cell sheets on stiff substrates and a tubular structure when cultured with soft hydrogels. To mimic the microvessels in vivo, researchers usually coculture the endothelial cells and pericytes from different adult tissues or derived from pluripotent stem cells in a three-dimensional hydrogel. However, there is a challenge for these models to reflect tissue-specific characteristics due to the vascular heterogeneity throughout the body. Here, we established a culture model for expanding adult tubular microvessels on stiff substrates with endothelial cells and pericytes derived from the same tissue. We isolated microvessels from adult rat subcutaneous soft connective tissue and cultured them on regular plastic dishes. We performed a series of screenings and formulated a custom-made medium (Medium-X), containing mainly antioxidants and three small molecules, Chir99021, A83-01, and Y27632. Medium-X significantly promoted adult microvessel growth while maintaining their characteristic tubular morphology up to 8 weeks in vitro, contrary to the monolayer of endothelial cell sheets in the commercially available medium EGM2MV. Transcriptomic analysis showed that Medium-X maintained the tubular morphology of microvessels by promoting angiogenesis and vascular remodeling while suppressing oxidation and lipid metabolic pathways. The model presented in this study can be applied to other organs for expanding organ-specific microvessels for tissue engineering and vascular regeneration.

bioengineering↗

bioRxiv2022

Extracellular matrix deposition precedes muscle-tendon integration during murine forelimb morphogenesis

The development of a functional vertebrate musculoskeletal system requires the combination of contractile muscle and extracellular matrix (ECM)-rich tendons that transmit muscle-generated force to bone. Despite the different embryologic origins, muscle and tendon integrate at the myotendinous junction (MTJ) to seamlessly connect cells and ECM across this interface. While the cell-cell signaling factors that direct development have received considerable attention, how and when the ECM linking these tissues is deposited remains unknown. To address this gap, we analyzed the 3D distribution of different ECM and the influence of skeletal muscle in forelimbs from wildype (WT) and muscle-less Pax3Cre/Cre mice. At E11.5, prior to MTJ integration, an aligned ECM was present at the presumptive insertion of the long triceps into the WT ulna. Mechanically robust tendon-like and muscle compartmentalization structures, positive for type I collagen, type V collagen, and fibrillin-2, still formed when muscle was knocked out. However, MTJ-specific ECM was not observed when muscle was absent. Our results show that an ECM-based template forms independent of muscle, but muscle is needed for the proper assembly of ECM at the MTJ. Summary statementAn aligned ECM template connects tendon and muscle during limb development, independent of muscle progenitor migration into the limb; however, the assembly of MTJ-specific ECM requires the presence of muscle.

developmental biology↗