Biology subjects

Tao, L.

Publications and source records attributed to Tao, L..

At least 19 recordsLinked to original sources

bioRxiv2026

A comparative single-cell transcriptomic atlas for diverse populations of vertebrate hair cells

Mechanosensitive hair cells vary widely in morphology and regenerative capacity across vertebrate organs and species. To investigate their underlying transcriptomic diversity, we integrated human, mouse, chicken, and zebrafish single-cell and single-nucleus RNA sequencing datasets and assembled a cross-species atlas of hair cells spanning organs, developmental stages, and species. Analysis of 29 hair cell populations, encompassing the major cochlear, vestibular, and lateral-line hair cell types, identified approximately 5,000 genes enriched in at least one hair cell population compared to supporting cells from the same organs. Unsupervised clustering of these hair cell-enriched (HCE) genes defined species-, organ-, and hair cell state-associated cohorts as well as broadly conserved hair cell-enriched programs. Using an AUC-based scoring framework, we further defined 884 pan hair cell-enriched (pan-HCE) genes with elevated expression in most developing and/or mature hair cell populations, including genes implicated in deafness, mechanotransduction, and synaptic transmission, along with genes not previously linked to hair cell function. Independent analysis of developing hair cells using the same metrics stratified pan-HCE genes based on when they are first enriched and identified an additional 97 genes that are transiently enriched. We used the pan- and developing HCE gene sets to assess transcriptional similarity between baseline hair cell states and hair cells produced during avian hair cell regeneration and in mouse cochlear organoids, as well as hair cell-like populations produced by fibroblast reprogramming. HCE gene sets with different developmental dynamics identified young vs. more mature hair cells when projected onto independent single-cell RNA sequencing datasets from developing zebrafish, mouse, and human. We provide a web-based resource of all HCE metrics and expression profiles, enabling future exploration of vertebrate hair cell gene expression across organs, species, and experimental contexts.

neuroscience↗

bioRxiv2026

scLANTERN: High-Throughput Retrospective Lineage Tracing via Full-Length Single-Cell Transcriptomics and Expressed Repeat Variation

Understanding the lineage relationships among individual cells is a key pursuit of modern biology, essential for unraveling the complexities of developmental processes and the adaptive mechanisms of disease progression, particularly in oncology. Retrospective single-cell clonal tracing has emerged as a transformative approach, offering a unique window into the evolutionary trajectories of cancer within clinical samples. While short-read single-cell transcriptomics (scRNA-seq) has revolutionized our ability to map cell states across human tumor atlases, it remains fundamentally limited in its capacity to link these states with high-resolution genomic alterations and the evolutionary trajectories inferred from these natural variants. Integrating somatic mutation discovery with transcriptomic profiles at single-cell resolution often requires separate, costly, and low-throughput genomic assays. Furthermore, existing methods frequently rely on exogenous genetic labeling or are restricted to short-read sequencing, which typically fails to resolve complex genomic rearrangements, large indels, or variations within highly repetitive regions,such as short tandem repeats (STRs), that could serve as potent endogenous clonal markers.

evolutionary biology↗

bioRxiv2026

IBDkb: an AI-enhanced integrative knowledge base for inflammatory bowel disease research and drug discovery

IBDkb (Inflammatory Bowel Disease Knowledge Base; https://www.biosino.org/ibdkb) is a freely accessible, integrated web-based platform that systematically curates and harmonizes multi-source data related to inflammatory bowel disease (IBD). To address the fragmentation and therapeutic gaps in existing specialized resources, IBDkb establishes a unified framework featuring advanced full-text search, interactive visualizations, cross-module knowledge graphs, and AI-powered utilities for real-time literature retrieval, trend analysis, text/PDF interpretation, and domain-specific conversational assistance. The platform currently integrates 98,453 research articles, 3,390 clinical trials, 200 investigational drugs, 200,606 bioactive compounds, 103 therapeutic targets, 77 experimental models, 12 pathogenesis summaries, and 15 treatment strategies. These integrated tools facilitate efficient exploration of complex associations among drugs, targets, trials, and mechanisms, thereby accelerating hypothesis generation and translational research in IBD. The platform is openly available without registration and supports data downloads. A case study on structure-aware drug comparison further demonstrates its utility in facilitating cross-disease drug repositioning hypotheses.

bioinformatics↗

bioRxiv2026

Dietary Non-protein Amino Acid AZE as an Environmental Trigger Activating Latent Genetic Susceptibility in C9orf72-ALS Pathogenesis

In human disease, clinical manifestations are not always tightly correlated with genetic etiology. While the GGGGCC (G4C2) hexanucleotide repeat expansion in the C9orf72 gene is the most prevalent genetic cause of ALS, a subset of mutation carriers stays asymptomatic. The molecular mechanisms underlying this incomplete penetrance remain elusive. Here, we identify L-azetidine-2-carboxylic acid (AZE), a dietary non-protein amino acid, as a critical environmental risk factor capable of unmasking latent genetic susceptibility in C9orf72-ALS pathogenesis. Specifically, AZE disrupts the proteasome-mediated clearance of toxic poly-GA dipeptide repeats derived from G4C2 repeats, triggering pronounced neuroinflammation and motor defects in a C9orf72-ALS mouse model that otherwise exhibits minimal phenotypes. Notably, AZE is widely present in the food chain (particularly in sugar beet) and consistently detectable in the postmortem human brains. A significant positive correlation was observed between sugar beet consumption and the incidence of sporadic C9-ALS cases in European nations. Critically, dietary intake of sugar beet juice is sufficient to activate subclinical genetic susceptibility in C9orf72-ALS mice. These findings reveal a direct diet-gene interplay in governing C9orf72-ALS penetrance, and propose dietary restriction of AZE-rich foods as a tangible strategy for genetically susceptible individuals to potentially delay or mitigate this currently incurable disorder.

neuroscience↗

bioRxiv2026

Loss of contractile pericytes and their impaired calcium dynamics exacerbate brain ischemic stroke of awake mice in acute and chronic phases

Ischemic stroke disrupts neurovascular uncoupling, in which neuronal activity fails to evoke appropriate microvascular blood flow responses, despite successful recanalization of upstream arteries. The cellular mechanisms underlying this dysfunction remain poorly defined. We examined Ca{superscript 2} signaling and contractile dynamics of vascular smooth muscle cells, precapillary sphincters and contractile pericytes, using two-photon microscopy and laser speckle imaging in awake mice subjected to transient middle cerebral artery occlusion. During occlusion, precapillary sphincters exhibited pronounced Ca{superscript 2} elevations and constriction, amplifying downstream capillary resistance. Following reperfusion, elevated Ca{superscript 2} signals persisted without proportional diameter changes, indicating early uncoupling between Ca{superscript 2} dynamics and vascular responses. In the chronic phase, loss of precapillary sphincters-associated contractile pericytes was associated with capillary dilation and persistent neurovascular uncoupling. Although partial recovery of pericyte coverage and Ca{superscript 2} activity occurred, stimulus-evoked vascular responses remained blunted. These findings highlight precapillary sphincters as a key contributor to ischemia-induced microvascular dysfunction.

neuroscience↗

bioRxiv2026

Spatiotemporally distinctive astrocytic and neuronal responses to repetitive intracortical microstimulation

Astrocytes are increasingly recognized as active modulators of neuronal synaptic transmission. Intracortical microstimulation (ICMS) is widely used to manipulate neuronal activity, yet the accompanying astrocytic responses remain poorly characterized. Using dual-color in vivo two-photon calcium imaging to simultaneously monitor neurons and astrocytes, we show that ICMS elicits astrocytic activation with spatiotemporal features that diverge from those of neurons. Astrocytes were recruited at stimulation intensities as low as 10A, thresholds sufficient to activate neurons, indicating that astrocytes robustly sense electrical perturbation. Unlike neurons, however, astrocytic responses were spatially heterogeneous and temporally variable across trials. At higher stimulation intensities (>=50A), astrocytic responsiveness, i.e., response peak amplitude, and number of responsive trials, progressively attenuated across repeated trials, in contrast to the stable and consistent neuronal responses. Although neuronally driven, astrocytes exhibited a distinct response profile under the same stimulation parameter, revealing a unique component of electrically evoked cortical activity that underscores the importance of incorporating glial physiology into future neuroprosthetic strategies.

neuroscience↗

bioRxiv2025

Fast and slow architectures of cortical dynamics in human brain

The human brain operates across a vast temporal range, from fast perception and action to slow physiological regulation. The capacity has attributed to a unitary cortical gradient of intrinsic timescales, yet such a unidimensional model cannot explain how local circuits simulateously support both rapid external behavior and slow internal body-coupled dynamics. Using SPLIT (spectral piecewise-linear inference of timescales) on a large-scale intracranial stereo-electroencephalography (8,619 contacts, 185 individuals), we identified dissociable fast (~10-100 Hz) and slow (~1-10 Hz) temporal components. Only the fast-component timescales followed the canonical sensorimotor-to-association cortical hierarchy. Slow-component timescales showed no hierarchical gradient, but were instead covaried with heart rate and enriched at site with heart-related neural responses. This dual temporal architecture persisted across wakefulness, rest, sleep, and anesthesia, challenging the unitary view of brain timescales and revealing an intrinsic bipartite organization that is associated with cortical hierarchy or neurophysiology.

neuroscience↗

bioRxiv2025

Multimodal profiling reveals a Notch-responsive regenerative subpopulation of cochlear supporting cells

Regeneration enables organisms to repair damaged tissues, yet this capacity is strikingly limited in the cochlear sensory epithelium, essential for sound detection. A major cause of hearing loss arises from the irreversible loss of sensory hair cells (HCs) in the cochlea. While supporting cells (SCs) have a latent ability to transdifferentiate into HCs, this regenerative potential is rapidly lost after development. Using live imaging and single-cell multi-omics of cochlear explants, we uncovered the cellular and molecular heterogeneity underlying the limited regenerative capacity of the neonatal mouse cochlea. Notch repression broadly silenced key SC genes, yet only a rare subpopulation of Deiters cells (DC), termed transdifferentiating DCs (tDCs), initiated the transdifferentiation into HC fate. These cells underwent coordinated transcriptional and enhancer remodeling, linking epigenetic priming with morphological plasticity, while other SCs remained refractory despite robust Notch targets downregulation. Our study provides a molecular definition of an early induced transitional DC to HC state, revealing Notch inhibition as a selective trigger that unmasks rare regenerative competence.

developmental biology↗

bioRxiv2025

Cell cycle-driven epigenetic resetting maintains stem cell fate for shoot branching

Adult mammalian stem cells typically maintain stem cell identity through proliferative quiescence. In contrast, we demonstrate that stem cell maintenance in Arabidopsis bud precursor cells requires active cell-cycle progression. Inhibiting division silences the shoot meristem marker gene SHOOT MERISTEMLESS (STM) and promotes differentiation. Whereas proliferation dilutes H3K27me3 levels to counteract silencing. Meanwhile, we identified two classes of transcription factors recruiting polycomb repressive complex 2 (PRC2) to epigenetically silence STM. The balance between these forces establishes a cell cycle-coupled epigenetic "Sisyphus" mechanism that maintains pluripotency. This cell fate switch is bistable; modeling and experimental data confirm that prolonged quiescence triggers irreversible differentiation. We propose that sequence-dependent PRC2 recruitment in plants enables precise silencing of fate-determining genes, while cell proliferation sustains pluripotency by resetting epigenetic marks.

plant biology↗

bioRxiv2025

Germline de novo mutation rate of the highly heterozygous amphioxus genome

Germline de novo mutations (DNMs) are the ultimate source of heritable variation, yet their patterns in highly heterozygous genomes remain poorly understood. Amphioxus, an early-branching chordate with exceptionally high genomic heterozygosity (3.2[~]4.2% in sequenced species), offers a unique model to explore mutational dynamics in such contexts. It is unclear whether high heterozygosity in amphioxus is due to a large effective population size, an increased mutation rate, or both. Here, we perform deep short-read whole genome sequencing of a two-generation pedigree of the amphioxus Branchiostoma floridae comprising two parents and 104 offspring, and develop a framework based on allele-aware parental assemblies as the reference to accurately identify DNMs. We detect 205 high-confidence DNMs, yielding a genome-wide mutation rate of 5.10 x 10-9 per base per generation, which is comparable to that of vertebrates. Combining this estimate with observed nucleotide diversity, we obtain an effective population size of [~]1.9 million, indicating that the elevated heterozygosity mainly results from a large effective population size. We observe a maternal-origin bias when considering all DNMs but a paternal-origin bias for early-occurring ones. Amphioxus harbors a much smaller fraction of CpG>TpG DNMs relative to vertebrates, attributable to its low methylation levels. We also investigate putative post-zygotic mutations in the offspring, revealing an unexpected paternal-origin bias. These suggest some distinct mutational mechanisms in amphioxus. Our study not only provides the first DNM measurement for amphioxus but also offers a generalizable strategy for studying DNMs in highly heterozygous genomes, facilitating mutation rate studies across chordates and other lineages.

genomics↗

bioRxiv2025

Direct detection of meiotic recombination events in the highly heterozygous amphioxus genome

Amphioxus, a basal chordate with highly heterozygous genomes (3.2[~]4.2% in sequenced species), represents a key model for understanding vertebrate origins. However, the extreme heterozygosity poses challenges for many genomic analyses, including studying meiotic recombination. Here, we present a novel bioinformatic pipeline that enables direct detection of crossover (CO) and non-crossover (NCO) recombination events using short-read whole-genome sequencing of a two-generation pedigree (two parents and 104 F1 offspring) of the amphioxus Branchiostoma floridae. Using parental assemblies generated by Platanus-allee as a custom reference for read alignment, we tracked inheritance patterns in offspring and phased contig-level haplotypes in parents, allowing us to detect recombination events. We identified 2,329 paternal and 2,288 maternal COs, yielding recombination rates of 4.57 cM/Mb and 4.49 cM/Mb, respectively. We found CO coldspots spanning >140 Mb in each parent and these are likely associated with large-scale heterozygous inversions. CO rates were positively correlated with transposable element and gene density in both sexes, but showed weak or no correlation with GC content. We further identified [~]10,000 paternal and [~]5,800 maternal NCO events, predominantly shorter than 200 bp in tract length, and found evidence of GC-biased gene conversion. This work provides the first direct and genome-wide measurement of recombination in amphioxus and demonstrates how high heterozygosity, often considered a barrier, can be leveraged for fine-scale recombination mapping. Our findings illuminate conserved and divergent features of recombination in chordates and establish a framework for studying recombination in other highly heterozygous organisms.

genomics↗

bioRxiv2025

Effective connectivity reveals dual-route mechanism of visual prediction precision via insula and pulvinar

The brains ability to weight predictions by their precision is a central mechanism in predictive processing, enabling optimal integration of prior expectations with incoming sensory input. Despite its theoretical significance, the neural circuitry that implements precision-weighted prediction remains unclear. Using 7-Tesla fMRI and dynamic causal modelling (DCM), this study investigated how the brain encodes the precision of predictions during a visual cueing task with high- and low-precision conditions. We focused on the key regions implicated in predictive processing: the insular cortex, the pulvinar nucleus of the thalamus, and primary visual cortex (V1). Behaviourally, participants showed significantly greater accuracy in the high-precision condition (p < .001), confirming effective task manipulation. DCM analyses revealed that high-precision predictions elicited excitatory modulation of connectivity from the insula to V1 (Pp = .95), alongside inhibitory influences from the insula to the pulvinar (Pp = .99) and from the pulvinar to V1 (Pp = .89). Furthermore, leave-one-out cross validation revealed that individual differences in behavioural sensitivity to precision were positively predicted by pulvinar-to-insula connectivity (r = .36, p = .026) and negatively predicted by the connectivity between pulvinar and V1 (pulvinar to V1: r = .35, p = .033; V1 to pulvinar: r = .37, p = .026), highlighting the behavioural relevance of these pathways. Together, these findings suggest a dual-route mechanism whereby the insula directly enhances top-down predictions in V1 while indirectly dampening bottom-up sensory input via the pulvinar. This mechanism may facilitate Bayesian integration under uncertainty and offers new hypotheses into how precision weighting may be disrupted in neuropsychiatric conditions.

neuroscience↗

bioRxiv2025

Structure and iron-transporting mechanism of brain organic cation transporter 1

Brain organic cation transporter 1 (BOCT1), also known as the solute carrier family 22 member 17 (SLC22A17) or the receptor for lipocalin-2 (LCN2), plays critical roles in health and disease. Its deficiency in mice results in early postnatal mortality and severe neurogenesis impairments. Despite its importance in physiology and pathophysiology, BOCT1s structure and transport mechanism remain elusive. Here, we integrate cryo-electron microscopy (cryo-EM), functional assays, biochemical experiments, and molecular dynamics simulations to elucidate the structure, substrate recognition, and transport mechanism of mouse BOCT1 (mBOCT1). The high-resolution cryo-EM structure reveals a distinctive N-terminal domain with a unique folding pattern dominated by a transmembrane loop atop TM6 (TML6), diverging from both known structures of SLC22 transporters and AlphaFold predictions. Notably, mBOCT1 functions as a high-capacity, low-affinity iron transporter independent of LCN2 binding. Iron transport is facilitated by a substrate gating mechanism involving TML6. These findings establish a structural basis for BOCT1s role as an independent iron transporter, enhancing our understanding of the transport mechanisms within major facilitator superfamily (MFS) transporters and providing new insights into brain iron homeostasis.

biophysics↗

bioRxiv2025

Single-Cell and Population-Level Neuromodulation Dynamics in Dual-Electrode Intracortical Stimulation

In neuroprosthetics, intracortical microstimulation (ICMS) recruits cortical networks to evoke brain responses and sensory perceptions. However, multi-electrode ICMS often generates suboptimal percepts compared to single-electrode ICMS, suggesting nonlinear neuromodulation rather than simple summation by multi-electrode ICMS. Yet, the factors and mechanisms underlying this modulation remain poorly understood. To investigate multi-electrode ICMS, we combined two-photon calcium imaging with a well-controlled dual-electrode ICMS in the mouse visual cortex to investigate how neurons integrate converging ICMS inputs at varying intensities. We found that stimulation intensity significantly shapes neuromodulation at both single-cell and population levels. Specifically, low intensities (5-7 {micro}A) have a minimal effect on neural responses. At intermediate intensities (10-15 {micro}A), we observed diverse, nonlinear bipolar modulation--both enhancement and attenuation--at the single-cell level. However, we achieved net enhancement at the population level. At higher intensities (15-20 {micro}A), although the proportion of modulated neurons increased in both enhancement and attenuation directions, the net effect at the population level was neutral (zero modulation). Furthermore, neurons strongly responsive to single-electrode ICMS were more likely to be attenuated, while weaker responding cells exhibited enhanced modulation. The strongest neuromodulatory effects occur at intermediate spatial distances in between the two electrodes. Computational modeling based on spiking neural network composed of adaptive exponential integrate-and-field neurons implicated the importance of inhibitory network dynamics and network variability as key mechanisms. Our experimental data was used to train an advanced deep learning approach, which successfully predicted the neuromodulation patterns induced by dual-electrode ICMS. Our findings reveal intensity- and spatial-dependent rules of neuromodulation by ICMS, providing necessary insights to optimize multi-electrode ICMS for neuroprosthetic applications. Significance statementUnderstanding how cortical neurons integrate concurrent inputs from multi-electrode intracortical microstimulation (ICMS) is essential for advancing neuroprosthetic technologies. We show that dual-electrode ICMS evokes distinct, predictable neuromodulatory effects that depend on (i) stimulation intensity, (ii) a neurons baseline responsiveness to single electrode input, and (iii) its proximity to the electrodes. Low and intermediate intensity dual-electrode ICMS amplifies neural activity compared to single-electrode ICMS, whereas high-intensity stimulation leads to attenuation, limiting net activation.

neuroscience↗

bioRxiv2025

Precise MRI-Histology Coregistration of Paraffin-Embedded Tissue with Blockface Imaging

Magnetic resonance imaging (MRI) provides 3D spatial information on tissue, yet it lacks at the molecular level. In contrast, histology provides cellular and molecular information, but it lacks the 3D spatial context and direct in vivo translation. Coregistering the two is key for the 3D-embedding of histological details, validating pathological MRI findings, and finding quantitative imaging biomarkers of neurodegenerative diseases. However, coregistration is challenging due to non-linear distortions of the tissue from histological processing and sectioning leading to microscopic and macroscopic nonlinear 3D deformations between specimen MRI and stained histology sections. To address this, we developed a novel pipeline, named Brewsters Blockface Quantification (BBQ), integrating robust optical approaches with innovative 2D and 3D registration algorithms to achieve precise volumetric alignment of specimen MRI data with histological images. On a variety of brain tissue specimens from distinct anatomical regions and across multiple species, our methodology generated blockface volumes with minimal distortion and artifacts. Using these blockface volumes as an intermediary, we achieve a precise alignment between MRI and histology slides, yielding registration results with an overlapping Dice score of [~]90% for whole tissue alignment between MRI and blockface volumes, and >95% for 2D MRI-histology registration. This correlative MRI-histology pipeline with robust 2D and 3D coregistration methods promises to enhance our understanding of neurodegenerative diseases and aid the development of MRI-based disease biomarkers.

bioengineering↗

bioRxiv2025

A Universal 6iL/E4 Culture System for Deriving and Maintaining Embryonic Stem Cells Across Mammalian Species

The derivation of authentic embryonic stem cells (ESCs) from diverse mammalian species offers valuable opportunities for advancing regenerative medicine, studying developmental biology, and enabling species conservation. Here, we report the development of a robust, serum-free culture system, termed 6iL/E4 that enables the derivation and long-term self-renewal of ESCs from multiple mammalian species, including mouse, rat, bovine, rabbit, and human. Using systematic signaling pathway analysis, we identified key regulators--including GSK3, STAT3, PDGFR, BRAF, and LATS--critical for ESC maintenance across species. Additionally, inducible expression of KLF2 and NANOG enhances the naive pluripotency and chimeric potential of bovine ESCs. The E4 medium also supports stable ESC growth while minimizing lineage bias. These findings reveal conserved principles underlying ESC self-renewal across divergent mammalian species and provide a universal platform for cross-species stem cell research, disease modeling, and biotechnology applications. In BriefWang et al. developed 6iL/E4, a serum-free system sustaining ESCs from mouse, rat, bovine, rabbit, and human. These findings reveal conserved fundamental mechanisms governing ESC self-renewal across diverse mammalian species. HighlightsO_LIDeveloped 6iL/E4 system for ESC derivation across five mammalian species. C_LIO_LIPDGFR signaling inhibition as critical for ESC derivation across species. C_LIO_LIE4 medium improves ESC maintenance and avoids neural bias of traditional N2B27. C_LIO_LIInducible KLF2/NANOG enhances naive pluripotency and chimera formation in bovine. C_LI

cell biology↗

bioRxiv2025

Distinct Ca2+ signatures of leptomeningeal fibroblast subgroups in awake mouse brains in health and inflammation

The leptomeninges, composed of the arachnoid mater, and pia mater, contains distinct subgroups of fibroblasts that differ in location and transcriptomic profiles. These fibroblasts contribute to the blood-cerebrospinal fluid barrier under physiological conditions, participate in fibrosis, and support blood-brain barrier integrity during injury and disease. However, their Ca2+ signaling profiles and underlying mechanisms in health and disease remain poorly understood. In this study, we divided leptomeningeal fibroblasts into three subgroups based on their locations: arachnoid fibroblasts, pia mater fibroblasts and perivascular fibroblasts. We employed two-photon microscopy in awake transgenic mice expressing Ca{superscript 2} indicators in leptomeningeal fibroblasts to investigate spontaneous and behaviorally evoked Ca{superscript 2} transients across different fibroblast subgroups. We found that each subgroup exhibits a distinct Ca{superscript 2} activity profile, with pia mater fibroblasts showing the highest-amplitude Ca{superscript 2} transients. Moreover, these fibroblasts displayed unique responses to both whisker air-puff stimulation and locomotion. We further demonstrated, using a chronically implanted cannula beneath the cranial window, that locomotion-associated vasodilation is followed by TRPV4 channel-mediated fibroblast Ca{superscript 2} elevations. Finally, systemic inflammation induced by lipopolysaccharide (LPS) reduced spontaneous Ca{superscript 2} transients in pia mater fibroblasts, likely due to macrophage infiltration following the inflammatory response. For the first time, this study characterizes spontaneous and behaviorally evoked Ca{superscript 2} dynamics in distinct leptomeningeal fibroblast subgroups in awake animals, providing novel insights into the functional roles of leptomeningeal fibroblasts in the healthy and diseased brain.

neuroscience↗

bioRxiv2025

Kinocilia of Vestibular Hair Cells: Bridging Structural and Functional Traits of Primary and Motile Cilia

Vestibular hair cells (HCs) convert gravitational and head motion cues into neural signals through mechanotransduction, mediated by the hair bundle--a mechanically integrated organelle composed of stereocilia and a kinocilium. The kinocilium, a specialized form of primary cilium, remains incompletely defined in structure, molecular composition, and function. To elucidate its characteristics, we conducted single-cell RNA sequencing of adult vestibular and cochlear HCs, uncovering a selective enrichment of primary and motile cilia-associated genes in vestibular HCs, particularly those related to the axonemal repeat complex. This enrichment of orthologous axonemal-related genes was conserved in zebrafish and human vestibular HCs, indicating a shared molecular architecture. Immunostaining validated the expression of key motile cilia markers in vestibular kinocilia. Moreover, live imaging of bullfrog and mouse HCs from crista ampullaris revealed spontaneous kinociliary motion. Together, these findings define the kinocilium as a unique organelle with molecular features of primary and motile cilia and suggest its previously unknown role as an active, force-generating element within the hair bundle.

neuroscience↗