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Han, K.

Publications and source records attributed to Han, K..

At least 37 records · Page 2Linked to original sources

TAFFISH: A lightweight, modular, and containerized workflow framework for reproducible bioinformatics analyses

SummaryBioinformatics analyses often rely on shell commands and small shell scripts whose executable context is difficult to preserve, inspect and reuse. TAFFISH addresses this gap by packaging command-line tool calls and lightweight shell flows as installable, versioned and inspectable executable units. Through a curated public Hub, TAFFISH indexes command interfaces, execution backends, platform constraints, release metadata and smoke-test/validation records. Together, these components provide a command-level reproducibility layer that works directly in ordinary shells and can also be invoked from existing workflow systems. Availability and ImplementationTAFFISH is implemented in Common Lisp and released under Apache-2.0. TAFFISH version 0.10.1, together with the source code, documentation and public Hub resources, is available at https://github.com/taffish/taffish, https://taffish.com, https://taffish.github.io and https://github.com/taffish/. The submitted software release, frozen Hub snapshot, test data, command logs, checksums and reproducibility package are archived at https://doi.org/10.5281/zenodo.21054185. The authors will maintain the software and public resources for at least two years after publication. ContactHao Lyu: hao.lyu@uestc.edu.cn; Hao Lin: hlin@uestc.edu.cn; Kejun Deng: dengkj@uestc.edu.cn Supplementary informationSupplementary data are available online.

bioinformatics↗

Asymmetric distribution of mitochondrial Ca2+ regulators specifies compartment-specific mitochondrial function and neuronal development

Neuronal polarization is essential for functional compartmentalization, enabling dendritic synaptic integration and axonal action potential generation. While structural differences in mitochondria across compartments have been identified, their functional distinctions remain unclear. Here, we uncovered compartment-specific mitochondrial Ca2+ dynamics and their molecular determinants. In axonal mitochondria, Ca2+ uptake through MCU occurs independently of ER-stored Ca2+ release, with faster matrix Ca2+ clearance than dendritic mitochondria, where Ca2+ uptake predominantly originates from ER Ca2+. The ER-independent mitochondrial Ca2+ uptake in axonal mitochondria is mediated by enriched MCU-regulating proteins, MICU1 and MICU2, while higher NCLX expression facilitates rapid Ca2+ clearance. Moreover, NCLX knockdown, which functionally mimics a mental retardation-associated mutation, caused more significant axonal branching defects compared to dendrites in vivo, aligning with its enrichment in axons. These findings highlight fundamental Ca2+-modulating features and developmental importance of neuronal mitochondria in a compartment-specific manner and reveal the key underlying molecular mechanisms.

neuroscience↗

Deep Volumetric Localization Super-Resolution Microscopy

Super-resolution microscopy, particularly localization-based methods, necessitates careful balancing of optical complexity, computational demands, and user accessibility. Conventional strategies typically adopt either deterministic or learning-based approaches, overlooking opportunities to leverage their syn-ergistic strengths. In this work, we introduce deep volumetric localization microscopy (VLM), a super-resolution methodology that integrates instrumental and algorithmic advancements for high-fidelity 3D single-molecule imaging. VLM employs a wavefront-optimized light-field configuration to capture single-molecule data, while a cascaded neural network reconstructs 3D volumes and extracts molecular coordinates at a 10 nm and 25 nm localization precision in the lateral and axial dimensions, respectively, across an imaging depth exceeding 5 {micro}m. Unlike existing methods, VLM is trained exclusively with system-aware intrinsic point-spread functions, bypassing dependencies on external imaging modalities or sample-specific data training. We validate VLM across diverse biological specimens, demonstrating hardware simplicity, data efficiency, and minimal phototoxicity. We anticipate VLM will overcome current limitations in fluorescence microscopy, empowering broader advancements in biomedical research.

bioengineering↗

Longitudinal deep phenotyping in a mouse model of West syndrome reveals temporal dynamics of synapse remodeling, gliosis, and proteomic and lipidomic changes during seizure evolution

Neurodevelopmental disorders can have long-lasting effects, causing not only early pediatric symptoms but also a range of neurological issues throughout adulthood. West syndrome is a severe neurodevelopmental disorder marked by infantile spasms, an early symptom that typically subsides with age. However, many patients progress to other seizure forms, known as seizure evolution, which is closely linked to poor long-term outcomes. Despite its clinical significance, the neurobiological mechanisms behind seizure evolution in West syndrome remain poorly understood. Recent genetic studies have consistently identified the CYFIP2 p.Arg87Cys variant in West syndrome patients, and the Cyfip2+/R87C mouse model carrying this mutation has been shown to recapitulate key symptoms of the disorder, including infantile spasms. In this study, we aimed to gain deeper insight into seizure evolution by conducting longitudinal deep phenotyping of the Cyfip2+/R87C mouse model from the neonatal stage to seven months of age. We tracked seizure activity through behavioral and EEG recordings and employed multi-omic analyses, including tissue and single-cell level transcriptomics, ultrastructural analysis, proteomics, and lipidomics, to capture a comprehensive view of molecular and cellular changes. Our results showed that after an initial period of neonatal spasms, Cyfip2+/R87C mice entered a seizure-free phase, followed by spontaneous recurrent seizures in adulthood, ultimately leading to premature death. This progression was associated with synaptic remodeling, sequential activation of different glial cell types, lipid droplet accumulation in astrocytes, and significant proteomic and lipidomic changes in the brain. These findings suggest that seizure evolution in West syndrome involves complex, time-dependent interactions between neurons and glial cells, along with alterations in lipid metabolism. Our study highlights the potential of longitudinal multi-omic approaches to uncover underlying mechanisms of seizure evolution and suggests that targeting these changes could offer novel therapeutic strategies. Additionally, the dataset generated here may provide valuable insights for other epilepsy and neurodevelopmental disorder models.

neuroscience↗

Homology-Based Enzymatic Assembly of Modular T7 Phage Genome

Bacteriophages, viruses that infect bacteria, are pivotal in therapeutic, industrial, and bio-detection applications due to their unique ability to inject DNA into bacterial hosts and change the genetics and behavior of whole bacterial populations. Genetic engineering of phage genomes has expanded their potential applications with several established methods such as Golden Gate assembly, yeast cloning, {lambda} Red recombineering, and CRISPR-Cas systems. Here, we present a novel, efficient method to design and make synthetic bacteriophages in vitro without using restriction enzymes to allow for modular insertion of DNA fragments into the phage genome. The ability to create synthetic bacteriophages in vitro without the use of restriction enzymes allows for simpler engineering without the hassle or cloning limitations encountered when building domesticated bacteriophage genomes.

bioengineering↗

Embryonically generated interneurons (EGINs) exhibit a distinctive developmental program and lamination in the olfactory bulb

Interneurons (INs) in the mouse olfactory bulb (OB) develop during an extensive period of time that begins in the embryo and continues throughout the lifetime of an individual. The connectivity and location of these neurons is profoundly affected by the time of generation, making these developmental windows critical to understand the circuitry of the OB. Here, we focus on the OB embryonic generated interneurons (or EGINs), which have generally received less attention than those generated in the adult. Birthdates of EGINs were differentiated by embryonic injections of thymidine analogs and their final destinations and phenotypes analyzed by immunohistochemistry. We found that EGINs were retained in the adult and were distributed across all layers of the OB. However, a lateral-to-medial neurogenic gradient is seen only in the earliest generated EGINs. Within the granule cell layer (GCL), EGINs predominantly accumulated in the superficial region at almost all ages and remained there during adulthood. Immunostaining for calbindin, parvalbumin, tyrosine hydroxylase, and calretinin were largely negative suggesting that EGINs may represent subpopulations of OB INs that are not yet fully characterized. Using in utero electroporation to label EGIN progenitors, we demonstrated that they reach the primordial OB as early as E13 and begin to differentiate apical dendrites by E15. At E16, EGIN progenitors clustered into a chain of migrating neuroblasts denoting the embryonic rostral migratory stream (RMS). Collectively, our data highlight the importance of studying OB INs in isolated time windows to better understand the formation of circuits that define the olfactory responses.

neuroscience↗

Interpretable multi-omics integration with UMAP embeddings and density-based clustering

Integrating high-dimensional cellular multi-omics data is crucial for understanding various layers of biological control. Single omic methods provide important insights, but often fall short in handling the complex relationships between genes, proteins, metabolites and beyond. Here, we present a novel, non-linear, and unsupervised method called GAUDI (Group Aggregation via UMAP Data Integration) that leverages independent UMAP embeddings for the concurrent analysis of multiple data types. GAUDI uncovers non-linear relationships among different omics data better than several state-of-the-art methods. This approach not only clusters samples by their multi-omic profiles but also identifies latent factors across each omics dataset, thereby enabling interpretation of the underlying features contributing to each cluster. Consequently, GAUDI facilitates more intuitive, interpretable visualizations to identify novel insights and potential biomarkers from a wide range of experimental designs.

bioinformatics↗

The transcriptomic landscape of spinal V1 interneurons reveals a role for En1 in specific elements of motor output

Neural circuits in the spinal cord are composed of diverse sets of interneurons that play crucial roles in shaping motor output. Despite progress in revealing the cellular architecture of the spinal cord, the extent of cell type heterogeneity within interneuron populations remains unclear. Here, we present a single-nucleus transcriptomic atlas of spinal V1 interneurons across postnatal development. We find that the core molecular taxonomy distinguishing neonatal V1 interneurons perdures into adulthood, suggesting conservation of function across development. Moreover, we identify a key role for En1, a transcription factor that marks the V1 population, in specifying one unique subset of V1Pou6f2 interneurons. Loss of En1 selectively disrupts the frequency of rhythmic locomotor output but does not disrupt flexion/extension limb movement. Beyond serving as a molecular resource for this neuronal population, our study highlights how deep neuronal profiling provides an entry point for functional studies of specialized cell types in motor output.

neuroscience↗

Human umbilical mesenchymal stem cell-derived mitochondria ameliorate maternal phenotype by improving placental mitochondria and vascular function in angiotensin II-induced preeclampsia rat

BackgroundMitochondrial transplantation (Mito-T) is a novel therapeutic strategy targeting ischemic cardiovascular diseases. Here, we tested the efficacy of human umbilical mesenchymal stem cell-derived mitochondria transplantation (Mito-T) on a rat model of PE. MethodsPE was induced by infusing angiotensin II (Ang II) to SD pregnancy rats on gestation day 8 (GD 8). Mito-T (100 g/l) was injected via jugular vein on GD 14. FindingsOn GD 20, PE rats showed high blood pressure, kidney and placental vascular abnormalities, reduced placental and fetal weights. Injected Mito-T was distributed intensively in the kidney, uterus and placenta of PE rats. Importantly, Mito-T reversed clinical manifestations of PE, restored placental abnormalities and reduced serum sFLT-1 levels and sFLT-1/PlGF ratio. In the placental mitochondria, Mito-T increased ETC complexes (complex I-V), improved mitochondrial membrane potential, ATP synthase and citrate synthase activities and biogenesis markers (PGC-1, TFAM, NRF1) and reduced ROS production. Mito-T increased mitochondrial fusion proteins (OPA1, MFN1 and MFN2), reduced mitochondrial fission proteins (DRP1 and FIS1) and mitophagy proteins (PINK, BNIP3, BNIP3L, FUNDC1), restored sFLT-1 regulating calcineurin-NFAT-dependent pathways in the placental tissue, primary trophoblast cells and Bewo cell line. Furthermore, eNOS, nNOS and AT2R mRNA and protein expressions were restored in placenta and trophoblast cells after Mito-T. InterpretationThis is the first study of PE treatment with Mito-T. Mito-T reverses pathological phenotypes of PE rats by improving placental mitochondrial and vascular function. The results provide proofs of concept of Mito-T as a potential therapeutic strategy for reducing maternal and fetal risks in PE patients. FundingThis work is supported by Korean National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (NRF-2019R1A2C1005720, NRF-2023R1A2C1005720), BK21 FOUR education program, Korean Society of Hypertension (Grant number KSH-R-2020), National Natural Science Foundation of China (NSFC 31660284, NSFC31860288).

pathology↗

Timing Matters: Lessons from Perinatal Neurogenesis in the Olfactory Bulb

In the olfactory bulb odorant receptor specific input converges into glomeruli. Deep to the glomeruli coding of odor information is tuned by local synaptic circuits. Deciphering the dendritic organization of granule cells relative to the secondary dendrites of projection neurons is a pivotal for understanding odor processing. We carried out a detailed interrogation of the granule cells including the timing of neurogenesis, laminar distribution and synaptogenesis between granule cells and projection neurons. In brief, the granule cells develop following a outside in maturation pattern from embryogenesis to adulthood following a developmental continuum. Granule cells born one week after birth exhibit a unique sublayer specific distribution pattern, marking a transition between embryonic or neonatal and adult stages. Integration into reciprocal synaptic circuits occurred 10 days post neurogenesis, We conclude that timing of neurogenesis dictates the anatomical configuration of granule cells within the olfactory bulb, which in turn regulates a preferential synaptic integration with either mitral cell or tufted cell secondary dendrites. Summary StatementThe integration and distribution of granule cells into the olfactory bulb is determined by the timing of neurogenesis. Location of somata shifts from superficial to deep during development.

neuroscience↗

BLOC1S1 control of vacuolar organelle fidelity modulates TH2 cell immunity and allergy susceptibility.

The levels of biogenesis of lysosome organelles complex 1 subunit 1 (BLOC1S1) control mitochondrial and endolysosome organelle homeostasis and function. Reduced fidelity of these vacuolar organelles is increasingly being recognized as important in instigating cell-autonomous immune cell activation. We reasoned that exploring the role of BLOC1S1 in CD4+ T cells, may further advance our understanding of regulatory events linked to mitochondrial and/or endolysosomal function in adaptive immunity. Transcript levels of the canonical transcription factors driving CD4+T cell polarization in response to activation showed that, the TH2 regulator GATA3 and phosphorylated STAT6 were preferentially induced in BLOC1S1 depleted primary CD4+ T (TKO) cells. In parallel, in response to both T cell receptor activation and in response to TH2 polarization the levels of IL-4, IL-5 and IL-13 were markedly induced in the absence of BLOC1S1. At the organelle level, mitochondrial DNA leakage evoked cGAS-STING and NF-kB pathway activation with subsequent TH2 polarization. The induction of autophagy with rapamycin reduced cytosolic mtDNA and reverses these TH2 signatures. Furthermore, genetic knockdown of STING and STING and NF-{kappa}B inhibition ameliorated this immune regulatory cascade in TKO cells. Finally, at a functional level, TKO mice displayed increased susceptible to allergic conditions including atopic dermatitis and allergic asthma. In conclusion, BLOC1S1 depletion mediated disruption of mitochondrial integrity to initiate a predominant TH2 responsive phenotype via STING-NF-{kappa}B driven signaling of the canonical TH2 regulatory program.

immunology↗

Charting Single Cell Lineage Dynamics and Mutation Networks via Homing CRISPR

Single cell lineage tracing, essential for unraveling cellular dynamics in disease evolution is critical for developing targeted therapies. CRISPR-Cas9, known for inducing permanent and cumulative mutations, is a cornerstone in lineage tracing. The novel homing guide RNA (hgRNA) technology enhances this by enabling dynamic retargeting and facilitating ongoing genetic modifications. Charting these mutations, especially through successive hgRNA edits, poses a significant challenge. Our solution, LINEMAP, is a computational framework designed to trace and map these mutations with precision. LINEMAP meticulously discerns mutation alleles at single-cell resolution and maps their complex interrelationships through a mutation evolution network. By utilizing a Markov Process model, we can predict mutation transition probabilities, revealing potential mutational routes and pathways. Our reconstruction algorithm, anchored in the Markov models attributes, reconstructs cellular lineage pathways, shedding light on the cells evolutionary journey to the minutiae of single-cell division. Our findings reveal an intricate network of mutation evolution paired with a predictive Markov model, advancing our capability to reconstruct single-cell lineage via hgRNA. This has substantial implications for advancing our understanding of biological mechanisms and propelling medical research forward.

bioinformatics↗

SpaGRN: investigating spatially informed regulatory paths for spatially resolved transcriptomics data

Cells expressing similar transcriptional regulatory circuits spatially aggregate into distinct cell types or states. However, most existing methods for inferring gene regulatory networks from spatially resolved transcriptomics are devoted to spatial co-expression modules or interactions between transcription factors and target genes, neglecting mediated effects from extracellular signals. Here we introduce SpaGRN, a statistical framework for predicting the comprehensive intracellular regulatory network underlying spatial patterns by integrating spatial expression profiles with prior knowledge on regulatory relationships and signaling paths. We validate and assess SpaGRN using simulated and real datasets, demonstrating its efficiency, performance, and robustness. When applied to 3D datasets of developing Drosophila embryos and larvae, SpaGRN identifies spatiotemporal variations in specific regulatory patterns, delineating the cascade of events from receptor stimulation to downstream transcription factors and targets, revealing synergetic regulation mechanism during organogenesis. Moreover, SpaGRN provides flexible visualization functions. We construct an online 3D regulatory network atlas database for interactive exploration and sharing.

bioinformatics↗

A Glance into the Density of Transcriptomic Activity, Embodied by the HOX Genes, in Neonatal and Aging Dermal Cells

Skin is an organ having a crucial role in the protection of muscle, bone, and internal organs and undergoing continuous self-renewal and aged. The growing interest in the prevention of skin aging and rejuvenation has sparked a surge of industrial and research studies focusing on the biological and transcriptional changes that occur during skin development and aging. In this study, we aimed to identify transcriptional differences between two main types of human skin cells: the HDFs and the HEK isolated from 30 neonatal and 30 adults (old) skin. Through differentially expressed gene (DEG) profiling using DEseq2, 604 up-, and 769 down-regulated genes were identified in the old group. The functional classification analysis using Metascape Gene Ontology and Reactome pathway was performed. We report the systematic transcriptomic changes in key biological markers involved in skin formation and maintenance and a unique difference in HOX gene families which are important for developing embryonic formation and regulating numerous biological processes. Among the 39 human HOX genes, 10 genes (HOXA10, 11, 13, HOXB13, HOXC11, and HOXD9-13) were significantly down-regulated, and 25 genes HOXA2-7, HOXB1-9, HOXC4-6 and 8-9, and HOXD1,3,4 and 8) were up-regulated, especially in the old HDFs. We have successfully established a correlation between HOX genes and the process of skin aging, thereby proposing HOX genes as a novel marker for assessing skin aging. Our findings provide compelling evidence supporting the involvement of HOX genes in this biological phenomenon such as skin aging.

genomics↗

BrainRBPedia: a resource for RNA-binding proteins relevant to neurodevelopmental disorders

RNA-binding proteins (RBPs) are crucial players in the post-transcriptional regulation of mRNA and play major roles in ensuring proper neuronal development and function. Deficits in RBP function have been implicated in a number of neurodevelopmental disorders including autism spectrum disorder (ASD) and intellectual disability (ID), yet we lack resources that integrate current knowledge of RBP function, tissue expression, and disease association in one place to aid in their experimental characterization. Here we introduce BrainRBPedia - a database of 1072 RBPs with both disease annotations for neurodevelopmental disorders and functional annotations relevant to these disorders, including loss-of-function intolerance and expression specificity to the brain, neurons, and neuronal development. Using these functional annotations, we develop a machine learning model to prioritize RBPs likely to be involved in ASD and ID. Our model indicates that RBPs with high loss-of-function intolerance and those upregulated during neuronal differentiation are disproportionately likely to contribute to ASD and ID etiology. In summary, BrainRBPedia comprises a unique resource for researchers interested in the experimental characterization of RBPs in relation to neurodevelopmental disorders and suggests functional signatures of RBPs likely to play a role in neurodevelopment.

bioinformatics↗

Outward-oriented sites within clustered CTCF boundaries are key for intraTAD chromatin interactions and gene regulation

CTCF plays an important role in adjusting insulation at TAD boundaries, where clustered CBS (CTCF-binding site) elements are often arranged in a somewhat tandem array with a complex divergent or convergent orientation. Here using cPcdh and HOXD loci as a paradigm, we look into the clustered CTCF TAD boundaries and find that, counterintuitively, outward-oriented CBS elements are crucial for inward enhancer-promoter interactions as well as for gene regulation. Specifically, by combinatorial deletions of a series of putative enhancer elements in vivo or CBS elements in vitro, in conjunction with chromosome conformation capture and RNA-seq analyses, we show that deletions of outward-oriented CBS elements weaken the strength of intraTAD promoter-enhancer interactions and enhancer activation of target genes. Our data highlight the crucial role of outward-oriented CBS elements within the clustered CTCF TAD boundaries and have interesting implications on the organization principles of clustered CTCF sites within TAD boundaries.

genetics↗

Spatially-resolved single-cell atlas of ascidian endostyle provides insights into the origin of vertebrate pharyngeal organs

The pharynx is an endoderm innovation in deuterostome ancestors, the vertebrate descendent structure of which is a pharyngeal developmental organizer involving multi-germ layer and organ derivatives. However, the evolutionary origination of complicated pharynx organs in vertebrates is still largely unknown. Endostyle, a transitional pharyngeal organ exclusively in basal chordates provides an opportunity to reveal the origin of pharyngeal organs. Here, utilizing cutting-edged Stereo-seq and single-cell RNA-seq, we constructed the first spatially-resolved single-cell atlas in the endostyle of urochordate ascidian Styela clava, where the spatial location of Stereo-seq and high capture efficiency of single-cell RNA-seq complement each other and identified 23 highly differentiated cell types. We identified a previously overlooked hemolymphoid region (HLR), which harbors immune and blood cell clusters with enriched stemness capacities, illuminating a mixed rudiment and stem-cell niches for the blood and lymphoid system. More excitingly, we discovered a mechanical-sensitive hair cell candidate in zone 3 homologous to vertebrate acoustico-lateralis system, which was supported by the expression of in situ hybridization-verified inner ear-specific markers, including PTPRQ, USH2A, WHRN, and ADGRV1, ultracellular structure evidence and cross-species comparison. These results thoroughly renewed the comprehension of the basal-chordate pharynx and provides expressional evidence for multiplexed pharyngeal organ evolution.

evolutionary biology↗

Surface-based Characterization of Gastric Anatomy and Motility using Magnetic Resonance Imaging and Neural Ordinary Differential Equation

Gastrointestinal magnetic resonance imaging (MRI) provides rich spatiotemporal data about the volume and movement of the food inside the stomach, but does not directly report on the muscular activity of the stomach itself. Here we describe a novel approach to characterize the motility of the stomach wall that drives the volumetric changes of the gastric content. In this approach, a surface template was used as a deformable model of the stomach wall. A neural ordinary differential equation (ODE) was optimized to model a diffeomorphic flow that ascribed the deformation of the stomach wall to a continuous biomedical process. Driven by this diffeomorphic flow, the surface template of the stomach progressively changes its shape over time or between conditions, while preserving its topology and manifoldness. We tested this approach with MRI data collected from 10 Sprague Dawley rats under a lightly anesthetized condition. Our proposed approach allowed us to characterize gastric anatomy and motility with a surface coordinate system common to every individual. Anatomical and motility features could be characterized for each individual, and then compared and summarized across individuals for group-level analysis. As a result, high-resolution functional maps were generated to reveal the spatial, temporal, and spectral characteristics of muscle activity as well as the coordination of motor events across different gastric regions. The relationship between muscle thickness and gastric motility was also evaluated throughout the entire stomach wall. Such a structure-function relationship was used to delineate two distinctive functional regions of the stomach. These results demonstrate the efficacy of using GI-MRI to measure and model gastric anatomy and function. This approach described herein is expected to enable non-invasive and accurate mapping of gastric motility throughout the entire stomach for both preclinical and clinical studies.

physiology↗