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Gu, J.

Publications and source records attributed to Gu, J..

At least 55 records · Page 3Linked to original sources

PERADIGM: Phenotype Embedding Similarity-based Rare Disease Gene Mapping

Identifying genes associated with rare diseases remains challenging due to the scarcity of patients and the limited statistical power of traditional association methods. Here, we introduce PERADIGM (Phenotype Embedding similarity-based RAre DIsease Gene Mapping), a novel framework that leverages natural language processing techniques to integrate comprehensive phenotype information from electronic health records for rare disease gene discovery. PERADIGM employs an embedding model to capture relationships between ICD-10 codes, providing a nuanced representation of individual phenotypes. By utilizing patient similarity scores, it enhances the identification of candidate genes associated with disease-specific phenotypes, surpassing conventional methods that rely on binary disease status. We applied PERADIGM to the UK Biobank dataset for three rare diseases: autosomal dominant polycystic kidney disease (ADPKD), Marfan syndrome, and neurofibromatosis type 1 (NF1). PERADIGM identified additional candidate genes associated with ADPKD-related and Marfan syndrome-related phenotypes, some of which are supported by existing literature, and demonstrated enhanced signal detection for NF1-specific phenotypes beyond traditional methods. Our findings demonstrate the potential of PERADIGM to identify genes associated with rare diseases and related phenotypes by incorporating phenotype embeddings and patient similarity, providing a powerful tool for precision medicine and a deeper understanding of rare disease genetics and clinical manifestations.

genetics↗

Precise, Specific, and Sensitive De Novo Antibody Design Across Multiple Cases

The precision design of antibodies, which naturally recognize diverse molecules through six variable loops, remains a critical challenge in therapeutic molecule discovery. In this study, we demonstrate that precise, sensitive, and specific antibody design can be achieved without prior antibody information across eight distinct target proteins. For each target, binders were identified from a yeast display scFv library of approximately 106 sequences, constructed by combining 102 designed light chain sequences with 104 designed heavy chain sequences. Binders with varying binding strengths were identified for all eight targets, including a case where no experimentally resolved target protein structure was available, demonstrating the highest level of precision compared to previous de novo antibody design reports. To further validate the designed antibodies, they were characterized in the IgG format for five distinct targets. The antibodies exhibited favorable developability properties, positioning them as promising hit or lead candidates. Notably, for one target in particular, the IgG-formatted antibodies exhibited affinity, activity, and developability, comparable to a commercial antibody, highlighting the sensitivity of the design method. Furthermore, binders capable of distinguishing closely related protein subtypes or mutants were identified, demonstrating that the method can achieve high molecular specificity. Cryo-EM analysis experimentally validated the designs accuracy by confirming that the key binding interactions were precisely as designed. These findings underscore the effectiveness of precision molecular design based on atomic-accuracy structure prediction. This study establishes computational antibody design as a viable approach for generating therapeutic molecules with tailored properties, with promising potential for achieving the efficacy and safety required for successful therapeutics.

bioengineering↗

A simple method for mapping the location of cross-β forming regions within protein domains of low sequence complexity

Protein domains of low sequence complexity are unable to fold into stable, three-dimensional structures. In test tube studies, these unusual polypeptide regions can self-associate in a manner causing phase separation from aqueous solution. This form of protein:protein interaction has been implicated in numerous examples of dynamic morphological organization within eukaryotic cells. In several cases, the basis for low complexity domain (LCD) self-association and phase separation has been traced to the formation of labile cross-{beta} structures. The primary energetic force favoring formation of these transient and reversible structures is enabled by polypeptide backbone interactions. Short, contiguous networks of peptide backbone amino groups and carbonyl oxygens are zippered together intermolecularly by hydrogen bonding as described by Linus Pauling seven decades ago. Here we describe a simple, molecular biological method useful for the identification of localized, self-associating regions within larger protein domains of low sequence complexity. SignificanceThis study describes a molecular biological method for analyzing protein domains of low sequence complexity in search of segments that mediate self-association and consequent phase separation both in vitro and in vivo. Small regions allowing for self-association correspond to sequences that specify the formation of labile cross-{beta} structural order. When juxtaposed to the C-terminus of GFP, cross-{beta} prone regions suppress fluorescence. A tiled scan of overlapping fragments of the low complexity domain (LCD) of the TDP-43 RNA binding protein pinpointed an evolutionarily conserved sequence of twenty amino acids essential for self-association, phase separation and the formation of nuclear speckles. The screening method described herein should be useful for the analysis of any LCD believed to function via homotypic self-association.

biochemistry↗

The expression of IL-35 in the prophase of liver failure and its preliminary exploration for the mechanism of immunoregulation by IL-35 and glucocorticoids

Background and AimsTo determine appropriate dosages for mice models in liver failure prophase and explore IL-35 and cytokine levels. Also, investigate changes in Treg/ Th17 ratio, IL-35, and IL-17 in patients with HBV-induced liver failure before and after treatment. MethodsWe induced liver failure in mice with different doses of concanavalin and assessed severity through serum biochemistry and pathology. Mice were divided into control, model, IL-35 plasmid, anti-IL-35, and dexamethasone groups. IL-35 and IL-17 expressions in liver tissue were evaluated via immunohistochemistry, fluorescence staining, and ELISA. Treg/Th17 ratio and IL-35 and IL-17 levels in peripheral blood of patients were measured using flow cytometry and ELISA, compared to 22 healthy individuals. ResultsThe optimal dose for the liver failure model was 20 g/ kg concanavalin. The IL-35 plasmid and dexamethasone groups showed significantly lower serum TBil, ALT, AST, IL-4, IL-17, TNF- , and liver histopathology scores compared to the model group, while the anti-IL-35 group showed higher levels (P<0. 05). In HBV-PLF patients, TBil, ALT, and AST significantly decreased, and PTA increased after glucocorticoid treatment (P<0. 05). Treg/ Th17 ratio was lower in HBV-PLF patients compared to the healthy group (P<0. 05), with higher IL-35 and IL-17 levels (P<0. 05). Post-treatment, Treg increased and Th17 decreased significantly; IL-17 and Treg/ Th17 ratios increased, while IL-35 decreased (P<0.05). IL-35 positively correlated with the Treg/Th17 ratio. Conclusions 20 g/ kg concanavalin proper dose for mice model. IL-35 may protect in liver failure. Glucocorticoids help maintain immune balance, prevent failure, increase ratios and IL-35 in HBV-PLF patients, and IL-35 related to Treg/Th17 balance.

immunology↗

Variance spectrum scaling analysis for high-dimensional coordination in human movement

Coordinated movement has been essential to our evolution as a species but its study has been limited by ideas largely developed for one-dimensional data. The field is poised for a change by high-density recording tools and the popularity of data sharing. New ideas are needed to revive classical theoretical questions such as the organization of the highly redundant biomechanical degrees of freedom and the optimal distribution of variability for efficiency and adaptiveness. Methods have been focused on increasing dimensions: making inferences from one or few measured dimensions about the properties of a higher dimensional system. The opposite problem is to record 100+ kinematic degrees of freedom and make inferences about properties of the embedded manifold. We present an approach to quantify the smoothness and degree to which the manifold is distributed among embedding dimensions. The principal components of embedding dimensions are rank-ordered by variance. The power-law scaling exponent of this variance spectrum is a function of the smoothness and dimensionality of the embedded manifold. It defines a threshold value beyond which the manifold becomes non-differentiable. We verified this approach by showing that the Kuramoto model close to global synchronization in the upper critical end of the coupling parameter obeys the threshold. Next, we tested if the scaling exponent was sensitive to participants gait impairment in a full-body motion capture dataset containing short gait trials. Variance scaling was highest in the healthy individuals, followed by osteoarthritis patients after hip-replacement, and lastly, the same patients pre-surgery. Thinking about manifold dimensionality, smoothness, and scaling could inform classic problems in movement science and exploration of the biomechanics of full-body action.

neuroscience↗

Absolute Quantification of Aging-Associated Glycans in IgG for Biological Age Prediction: Insights from Glycomics and Transcriptomics

Immunoglobulin G (IgG) N-glycans have been identified as associated with aging; however, previous studies predominantly quantified changes based on the relative percentages of each glycan within the total glycan pool, neglecting the absolute concentration changes of individual glycans. Additionally, relative quantification can limit practical applications, as these often require absolute concentration measurements for consistent and interpretable biomarker values. In this study, we introduce a novel strategy for discovering aging-associated IgG glycans and establishing a prediction model based on their absolute concentration alteration. We employed a glycome quantification technology to identify the alteration in IgG glycan amount in natural aging and anti-aging (caloric restriction) models, discovering aging-related glycans. The glycomics analysis revealed key features: downregulation of bisected glycan GP3 (F(6)A2B) and upregulation of digalactosylated glycan GP8 (F(6)A2G2). These glycan changes showed significant fold changes from an early stage. Using external standards of these two glycans, we subsequently measured the absolute concentrations of them, allowing us to establish a predictive model, abGlycoAge, for biological aging. The abGlycoAge index suggested a younger state under caloric restriction, with an average age reduction of 3.9-14 weeks. Additionally, we performed RNA sequencing on splenic B cells of mice, suggesting Derl3, Smarcb1, Ankrd55, Tbkbp1 and Slc38a10 could contribute to the alteration of GP3 and GP8 in aging. This analysis enhances our understanding of glycan alterations, accounts for individual variability, and aids in designing effective anti-aging strategies. These findings highlight the crucial roles of the GP3 and GP8 as potential biomarkers for aging and health.

biochemistry↗

ORP2 regulates free cholesterol accumulation in hepatocytes during MASH

BackgroundCholesterol crystals in hepatocytes are known to strongly associate with human Metabolic Dysfunction-Associated Steatohepatitis (MASH). However, it remains unclear which molecular pathway(s) regulates free cholesterol accumulation, and therefore the formation of cholesterol crystals in hepatocytes. In cultured cell lines, oxysterol-binding protein-related protein 2 (ORP2) functions to deliver cholesterol to the plasma membrane from internal organelles. MethodsHere, we generated liver-specific ORP2 knockout (ORP2-LKO) mice and characterized their metabolic phenotypes on chow and high fat diet. ResultsThe ORP2-LKO mice developed much more severe hepatic steatosis than wild type mice after high-fat diet feeding. They also demonstrated more severe liver inflammation and damage. Notably, free but not esterified cholesterol, as well as cholesterol crystals accumulated in ORP2-LKO liver. The expression of Cyp7a1 was significantly upregulated in ORP2-LKO liver, accompanied with accumulation of taurocholic acid. Our results thus unveil an important in vivo function of ORP2 in preventing free cholesterol from accumulating in mouse liver. Conclusionsour results suggest that impaired cholesterol trafficking may enhance the deposition of cholesterol crystals in hepatocytes, promoting the development of MASH.

cell biology↗

Auditory tract maturation in early infancy: Links to speech production

Infants exhibit remarkable language acquisition abilities, supported by highly plastic neural substrates that dynamically interact with early speech experiences. However, the developmental mechanisms of these neural substrates and their specific role in speech acquisition remain incompletely understood. Here, we present NeoAudi Tract (NAT), a robust automated toolbox for extracting the full set of auditory tracts in infants from birth to 24 months using 3T diffusion MRI data. By characterizing the microstructural changes in these tracts, we demonstrate a gradual and continuous maturation process of the auditory system. Additionally, we identify significant correlations between auditory tract maturation and both fine-motor skills and expressive language t-scores from the Mullen Scales of Early Learning tests. Our findings highlight the role of the auditory system in speech production and indicate the intertwined development of auditory and motor systems that underlies speech acquisition, particularly during perceptual reorganization.

neuroscience↗

C2AM-Unet: Coordinate and Channel Attention Mixing Flexible Architecture for Retinal Vessel Segmentation

Accurate retinal Microvascular segmentation demands a balanced combination of anatomical fidelity and hemodynamic relevance. However, existing methods fall short in preserving critical structures such as capillary junctions and bifurcations, thus limiting clinical applications and causing fragmentation. To address these limitations, we propose DFMS-Net, a novel dualfield segmentation framework that synergistically integrates geometric-field modeling--achieved through the Spatial Pathway Extractor (SPE) and Transformer-based Topology Interaction (TTI) for preserving structural continuity--and functional-field optimization--realized by the Semantic Attention Amplification (SAA) module for enhancing semantic visibility--via a unified Dual-Field Hemo-dynamic Attention (DFHA) mechanism. This core module enables joint enhancement of vessel continuity, accurate resolution of complex branching patterns, and recovery of low-contrast capillaries, all under physiological guidance. By co-optimizing geometric and functional cues within a unified attention learning paradigm, DFMS-Net produces segmentations that are both morphologically accurate and hemodynamically plausible. Furthermore, we propose two specialized variants using a streamlined Double SPE Attention for vessel continuity refinement. To address the directionality-dependent nature of structural damage in retinal ischemia and glaucoma, we propose Variant-1--a streamlined architecture that emphasizes dual-stage directional refinement to enhance trajectory coherence and improve the detection of topological disruptions, while Variant-2 supports high-resolution analysis of capillary dropout in early diabetic retinopathy through detailed microvascular recovery. Extensive experiments on retinal (DRIVE, STARE) and coronary angiography (DCA1, CHUAC) datasets demonstrate that DFMS-Net achieves state-of-theart performance. Meanwhile, its strong generalization capability offers a promising foundation for diagnosing both retinal and cardiovascular diseases. The code will be available at https://github.com/699zjl/DFMS-Net-new.

bioinformatics↗

scTrace+: enhance the cell fate inference by integrating the lineage-tracing and multi-faceted transcriptomic similarity information

Deciphering the cell state dynamics is crucial for understanding biological processes. Single-cell lineage tracing technologies provide an effective way to track the single-cell lineages by heritable DNA barcodes, but the high missing rates of lineage barcodes and the intra-clonal heterogeneity bring great challenges for dissecting the mechanisms of cell fate decision. Here, we systematically evaluate the feature of single-cell lineage tracing data, and then develop an algorithm scTrace+ to enhance the cell dynamic traces by incorporating multi-faceted transcriptomic similarities into lineage relationships via a Kernelized Probabilistic Matrix Factorization model. We assess its feasibility and performance by conducting ablation and benchmarking experiments on multiple real datasets, and show scTrace+ can accurately predict the fates of cells. Further, scTrace+ effectively identifies some important driver genes implicated in cellular fate decision of diverse biological processes, such as the cell differentiation or the tumor drug responses.

bioinformatics↗

Dynamic Differences in Clinically relevant Pen β-Lactamases from Burkholderia spp.

Antimicrobial resistance (AMR) is a global threat, with Burkholderia species contributing significantly to difficult-to-treat infections. Ambler Class A Pen {beta}-lactamases are produced by all Burkholderia spp., and their mutation or overproduction leads to the resistance of {beta}-lactam antibiotics. This study investigates the dynamic differences among four Pen {beta}-lactamases (PenA, PenI, PenL and PenP) using machine learning driven enhanced sampling molecular dynamics simulations, Markov State Models (MSMs), convolutional variational autoencoder-based deep learning (CVAE) and the BindSiteS-CNN model. Although sharing the same catalytic mechanisms, these enzymes exhibit distinct dynamic features due low sequence identity, resulting in different substrate profiles and catalytic turnover. The BindSiteS-CNN model further reveals local active site dynamics, offering insights into the Pen {beta}-lactamase evolutionary adaptation. Our findings reported here identify critical mutations and proposes new hotspots affecting Pen {beta}-lactamase flexibility and function, which can be used to fight emerging resistance in these enzymes.

biophysics↗

Domain-specific Schema Reuse Supports Flexible Learning to Learn in Primate Brain

Prior knowledge accelerates subsequent learning of similarly structured problems - a phenomenon termed "learning to learn" - by forming and reusing generalizable neural representations, i.e., the schemas. However, the stability-plasticity dilemma, i.e., how to exploit stable schemas to facilitate learning while remaining flexible towards possible changes, is not well understood. We hypothesize that restricting schemas to specific functional, e.g., decision-making, subspace and making it orthogonal to other subspaces allows the brain to balance stability and plasticity. To test it, we trained three macaques on visuomotor mapping tasks and recorded neural activity in the dorsolateral premotor cortex. By delineating decision and stimulus subspaces, we identified a schema-like manifold within only the decision subspace. The reuse of decision schemas significantly facilitated subsequent learning. In addition, the decision subspace exhibited a trend to be orthogonal to the stimulus subspace, minimizing interference between these two domains. Our results revealed that restricting schemas to specific functional domains can preserve useful knowledge while maintaining orthogonality with other subspaces, allowing for flexible adaptation to new environments, thereby resolving the stability-plasticity dilemma. This finding provides new insights into the mechanisms underlying brains capability to learn both fast and flexibly, which can also inspire more efficient learning algorithms for artificial intelligence systems towards working in open, dynamic environments.

neuroscience↗

Genomic landscape of antiviral defense systems in prokaryotes and phages

Prokaryotes and their viruses have co-evolved for billions of years, resulting in emergence of numerous antiviral defense systems. With the development of bioinformatic technologies and experimental studies, more and more novel defense systems have been discovered in the near decades. However, the origin and mechanism of these systems are still largely unknown. This study provides a systematic analysis of 132 defense systems within 212,599 prokaryotic genomes, which should be the largest analyzed data so far, revealing the diversity and distribution of these systems across different taxonomic units. Our findings also reveal that not only well-studied bacteria, but also archaea and virus encode diverse antiviral defense systems with specific features. In summary, this work classify 132 known defense systems, provides a comprehensive view of prokaryotic defense systems and insights into the evolution of immune responses.

microbiology↗

Hand Position Fields of Neurons in the Premotor Cortex of Macaques during Natural Reaching

Planning and execution for goal-directed movements requires the integration of the current position of body or body parts with various kinematic parameters of the movement itself. In the hippocampus, the field-based representation of spatial information plays an essential role in this process during navigation. However, if a similar, field-based encoding framework is also utilized by the motor areas during hand reaching remains unclear. In this study, we investigated the hand position tuning in the dorsal premotor cortex (PMd) neurons (n = 601) when four monkeys performing a naturalistic reach-and-grasp task. We show that 132/601 (22%) of PMd neurons increased their firing rates when the monkeys hand occupied specific positions in the space, forming the "position fields" in their spatial firing maps that can be well described by 2D Gaussian functions/kernels. We further analyzed how the field-tuning of hand position is co-represented with other task-related parameters including the hand moving direction, speed, and reward location in the same population of PMd neurons, revealing a mixed-selective framework also similar to that discovered in the hippocampus. These position-tuned cells demonstrated high efficiency in encoding hand position, with ~10% of overall recorded neurons contributing >80% of accuracy in decoding instantaneous hand moving trajectories. These results suggest that a field-based encoding framework of position may be a common component to representing spatial information and integrating it with kinematic parameters for guiding goal-directed movements of the body or body parts.

neuroscience↗

Patterned wireless transcranial optogenetics generates artificial perception

Synthesizing perceivable artificial neural inputs independent of typical sensory channels remains a fundamental challenge in the development of next-generation brain-machine interfaces. Establishing a minimally invasive, wirelessly effective, and miniaturized platform with long-term stability is crucial for creating a clinically meaningful interface capable of mediating artificial perceptual feedback. In this study, we demonstrate a miniaturized fully implantable wireless transcranial optogenetic encoder designed to generate artificial perceptions through digitized optogenetic manipulation of large cortical ensembles. This platform enables the spatiotemporal orchestration of large-scale cortical activity for remote perception genesis via real-time wireless communication and control, with optimized device performance achieved by simulation-guided methods addressing light and heat propagation during operation. Cue discrimination during operant learning demonstrates the wireless genesis of artificial percepts sensed by mice, where spatial distance across large cortical networks and sequential order-based analyses of discrimination performance reveal principles that adhere to general perceptual rules. These conceptual and technical advancements expand our understanding of artificial neural syntax and its perception by the brain, guiding the evolution of next-generation brain-machine communication.

neuroscience↗

Accurate antibody loop structure prediction enables zero-shot design of target-specific antibodies

Protein loops, characterized by their versatile structures with varying sizes and shapes, can recognize a wide range of targets with high specificity and affinity. The variable loops of the antibody complementarity-determining region (CDR) are particularly crucial for immune responses and therapeutic applications due to their effective target recognition capabilities. Accurate structure prediction of these antibody loops is essential for the efficient in silico design of target-binding antibodies for therapeutic or industrial use. However, predicting antibody loop structures is challenging due to the lack of evolutionary information from related proteins. Thus, a successful ab initio structure prediction method, which operates without structural templates or related sequences, is crucial for the effective design of antibody loop-mediated interactions. This study demonstrates that highly accurate antibody loop structure prediction enables the effective zero-shot design of target-binding antibody loops. The performance of loop design has been shown to depend on the accuracy of ab initio loop structure prediction, as tested with two versions of our design model. The high affinity, diversity, novelty, and specificity of the antibody loops designed with these new methods were validated experimentally on four target proteins.

bioengineering↗

Optimized semi-specific PCR amplification using arbitrarily degenerate primer for genome-wide genotyping and its application in peanut genetic diversity study

Cultivated peanut (Arachis hypogaea L.) is an important legume crop with a large genome size but a limited genetic diversity. Evaluating the genetic variation among diverse peanut germplasms using genome-wide molecular markers is an effective strategy to explore its genetic diversity and thereby facilitate peanut improvement. In this study, we introduced a novel whole-genome genotyping (WGG) technique named dRAPD-seq (degenerate Random Amplification Polymorphic DNA and sequencing), which relies on semi-specific PCR amplification by arbitrarily degenerate (AD) primer and next-generation sequencing (NGS), and demonstrated its robust reproducibility and high accuracy. Subsequently, we applied dRAPD-seq to investigate the genetic relatedness within a population of 101 diverse peanut accessions and identified a low genetic diversity among these accessions. Our phylogenetic tree, population structure analyses, and principal component analysis (PCA) indicated that this population could be clustered into three subpopulations, largely corresponding to three botanical types. In conclusion, this research not only introduced a cost-effective and easy-to-conduct WGG method but also provided valuable insights for utilizing these peanut accessions in future breeding programs.

genomics↗

BMAP: a comprehensive and reproducible biomedical data analysis platform

In the realm of biomedical research, efficient data analysis and processing are crucial due to the escalating volume and complexity of data generated by research teams. Managing these vast arrays of localized data presents significant challenges, necessitating precise, efficient, and reproducible analysis methodologies to ensure the integrity and reliability of scientific outcomes. Traditional management of analysis codes, computing environments, and the inherent difficulties in result traceability due to team dynamics often lead to inefficiencies and potential risks in maintaining academic integrity. Furthermore, while online storage platforms such as Dryad, GitHub, and Docker facilitate data, code, and environment management, they do not inherently guarantee the reproducibility of results, with issues like data incompleteness, forgotten parameters, or software discrepancies posing additional challenges. To address these critical gaps, we developed a BioMedical data Analysis Platform (BMAP) to offer online and localized categorized management of research assets. BMAP enhances workflow efficiency by transforming complex pipelines into user-friendly web applications, promoting consistency and standardization across team analyses. Its comprehensive web analysis module and seamless integration with data and computing resources support automated result reproducibility and visualization. According to the assessment, 1,692 omics-related figures from 101 recent articles, across 45 visualization types, were tested with BMAP, which could cover 37.8% of the types and 64.3% of the figures. BMAP also enables the sharing and enhancement of research methods through its cloud platform, allowing researchers to utilize the previously developed and validated tools, thereby reducing redundant effort and minimizing analytical discrepancies due to methodological differences.

bioinformatics↗