Biology subjects

Watanabe, M.

Publications and source records attributed to Watanabe, M..

At least 19 recordsLinked to original sources

bioRxiv2026

Nanoscale remodeling of synaptic glutamate receptors and calcium channels in temporal lobe epilepsy

Temporal lobe epilepsy (TLE) is the most common form of focal epilepsy and remains drug-resistant in approximately one-third of patients, for whom surgical resection of the epileptogenic zone is currently the most effective treatment option. One strategy to improve therapeutic outcomes involves identifying the molecular mechanisms and key regulators underlying synaptic function. Although altered glutamatergic neurotransmission is considered a major contributor to epileptic hyperexcitability, the nanoscale organization of key synaptic proteins in the human epileptic cortex is still not well characterized. In particular, it remains unclear whether pre- and postsynaptic proteins undergo synapse-type-specific remodeling in TLE. Here, we used high-resolution freeze-fracture replica immunolabeling to map the nanoscale organization of postsynaptic AMPA receptors (AMPARs) and presynaptic P/Q-type voltage-gated calcium channels (CaV2.1) in glutamatergic synapses of cortical layers II/III of surgically resected human tissue. We examined perilesional, cytologically unremarkable, non-epileptogenic cortical tissue obtained from patients undergoing tumor resection (52-63 years; two female and three male patients) and compared these data with cortical samples from patients with refractory TLE (22-53 years; two female and four male patients). To assess whether pathological remodeling differs across synapse populations, we analyzed both excitatory dendritic spine and shaft synapses. We found a robust, highly consistent increase in AMPAR density at both spine and shaft synapses in TLE patients indicating enhanced postsynaptic excitatory signaling. However, AMPAR spatial reorganization differed between synapse types. Monte Carlo simulations demonstrated that spine synapses largely preserved a random receptor distribution without a significant clustering pattern, whereas shaft synapses exhibited a redistribution from clustering toward random receptor arrangements together with reduced center-preference within the postsynaptic density. In contrast, presynaptic CaV2.1 remodeling was more variable and predominantly associated with excitatory spine synapses. TLE spine synapses exhibited an overall increase in CaV2.1 density together with significantly larger and more numerous CaV2.1 nanoclusters within the active zone. This difference was particularly pronounced in male patients. In comparison, shaft synapses displayed only minor presynaptic alterations. CaV2.1 channels remained highly clustered under both control and epileptic conditions, indicating preservation of core active-zone organizational features despite disease-associated nanoscale remodeling. Together, these findings provide direct ultrastructural support that pathological plasticity in human TLE involves an overall increase in excitatory postsynaptic responsiveness and a target cell-specific increase of excitatory release probability at cortical synapses.

neuroscience↗

bioRxiv2026

A Multiplex Protein Microarray Platform for Preclinical Tissue Binding and Cross-Reactivity of Therapeutic Antibodies

The NexAb multiplex protein microarray platform, comprising a 7,015-spot tissue lysate array and antigen-oriented protein arrays, was developed for preclinical tissue-binding and cross-reactivity assessment of therapeutic antibodies. Four anti-HER2 antibodies, trastuzumab, pertuzumab, trastuzumab emtansine (T-DM1), and trastuzumab deruxtecan (T-DXd), were profiled with integrated ERBB2 mRNA data. On antigen-oriented arrays, cell-synthesized HER2 bound trastuzumab and pertuzumab strongly and epitope-dependently, whereas wheat-germ HER2 showed no binding. On the tissue lysate array, trastuzumab and T-DM1 bound HER2-positive cancer cell lines and tumor tissues with nearly identical profiles (correlation coefficient r = 0.991), and T-DXd bound ERBB2-low cancer spots and 38.8% of normal human tissue spots, a profile not conserved in cynomolgus monkeys. Trastuzumab, T-DM1, and pertuzumab showed no cross-reactivity with cynomolgus monkey tissues, whereas T-DXd bound 3.1% of monkey tissue spots. NexAb enables quantitative cross-reactivity profiling relevant to preclinical safety evaluation.

pharmacology and toxicology↗

bioRxiv2026

Elucidation of the second-phase freezing acclimation mechanism: plants accumulate sugars via photosynthesis under frozen conditions

Overwintering plants increase their tolerance to freezing in two phases: the first-phase, known as cold acclimation (CA), occurs at chilling temperatures, followed by second-phase acclimation at sub-zero temperatures. We previously showed that second-phase freezing acclimation (2PFA), in which cold-acclimated Arabidopsis is exposed to -2{degrees}C with extracellular ice formation under light, confers the highest freezing tolerance (LT50 below -20{degrees}C) through a pathway requiring photosynthetic electron transport, possibly independent of the CBF-COR pathway. However, how light enhances freezing tolerance in frozen plants remains unclear. Here, we developed a system to measure chlorophyll fluorescence in intact plants maintained in a frozen state, and found that PSII retained substantial photochemical capacity (Fv/Fm) in frozen leaves. Comparative transcriptomics revealed that 2PFA under light induced genes involved in starch, sucrose and galactose metabolism. Consistently, soluble sugars, mainly sucrose, glucose and fructose, accumulated to levels approximately 8-fold higher than those in CA plants, and total sugar content was strongly correlated with freezing tolerance. This accumulation was suppressed by the photosynthetic electron transport inhibitor DCMU. These results suggest that photosynthetic activity is maintained in frozen plants and supplies sugars that may contribute to the freezing tolerance acquired during second-phase acclimation, beyond the level achieved by first-phase CA, unveiling a previously unrecognized mechanism in the winter survival strategy of plants.

plant biology↗

bioRxiv2026

Enhancing the hyaline cartilage regenerative potential of induced pluripotent stem cell-derived chondrocyte cell sheets

Introduction Autologous and allogeneic chondrocyte cell sheet transplantation has shown safety and potential efficacy for cartilage defects associated with knee osteoarthritis. Although polydactyly-derived chondrocyte (PDC) cell sheets have been used clinically for allogeneic transplantation, a scalable and reliable alternative cell source is needed. This study aimed to establish a proof-of-concept protocol for generating chondrocyte cell sheets from clinical-grade human induced pluripotent stem cells (iPS cells). Methods Cartilaginous tissue was generated from human iPS cells, and isolated chondrocytes were used to fabricate iPS cell-derived chondrocyte sheets. In Phase 1, sheets were produced in high-serum medium under normoxic, hypoxic, or hypoxic/high-seeding-density conditions and compared with PDC sheets using a three-dimensional in vitro model and xenogeneic orthotopic transplantation in an immunodeficient rat model. In Phase 2, sheets were produced in low-serum medium under hypoxic/high-seeding-density conditions and evaluated for cartilage-related gene expression, secreted factors, cell surface marker expression, and in vivo cartilage repair. Results In Phase 1, hypoxic/high-seeding-density culture enhanced in vitro chondrogenic properties. However, after transplantation, iPS cell-derived chondrocyte sheets formed fibrotic repair tissue, whereas PDC sheets generated hyaline-like cartilage. In Phase 2, low-serum culture increased expression of cartilage-related genes, including collagen type II alpha 1 (COL2A1) and SRY-box transcription factor 9 (SOX9), enhanced secretion of transforming growth factor beta 1 and melanoma inhibitory activity, and upregulated CD9, CD26, CD56, CD201, CD227, and GD2. Low-serum iPS cell-derived chondrocyte sheets regenerated hyaline cartilage at 4 weeks, and the repair tissue was maintained at 12 weeks without bone formation. Conclusions A robust fabrication protocol enabled human iPS cell-derived chondrocyte sheets to regenerate hyaline-like cartilage in vivo. These findings support their potential as a scalable cell source for clinical cartilage repair.

bioengineering↗

bioRxiv2026

Curcumin Enhances Alcoholic Fermentation in Yeast by Promoting Osmotic Stress Adaptation

Spices contain diverse plant secondary metabolites with antimicrobial and antioxidant activities that can influence plant-microbe interactions. Among these metabolites, curcumin and piperine are major bioactive constituents of turmeric and black pepper, respectively. In this study, we demonstrate that curcumin and piperine enhance alcoholic fermentation in the budding yeast Saccharomyces cerevisiae. Curcumin significantly promoted alcoholic fermentation under high-glucose conditions (20-40% glucose), which impose substantial osmotic stress on yeast cells. Under these conditions, curcumin enhanced yeast growth, improved osmotic stress tolerance, and increased resistance to cell wall digestion, suggesting enhanced stress adaptation during fermentation. Furthermore, deletion of HOG1, which encodes the central MAP kinase of the High-Osmolarity Glycerol (HOG) pathway responsible for the osmotic stress response, abolished the fermentation-enhancing effect of curcumin, indicating that Hog1 function is required for this effect. Consistent with this result, transcriptomic and RT-qPCR analyses revealed increased expression of stress adaptation-related genes, including known HOG pathway-responsive genes. In contrast, the expression of genes involved in amino acid catabolism was decreased at 12 h after the initiation of fermentation, while metabolomic analysis revealed increased intracellular levels of amino acids, including glutamate and asparagine, at 24 h. These coordinated transcriptional and metabolic changes are consistent with reduced amino acid catabolism and a shift toward a metabolic state favorable for sustained fermentation. Together, these findings suggest that curcumin enhances alcoholic fermentation under osmotic stress by promoting stress adaptation that supports yeast growth and sustained fermentation.

microbiology↗

bioRxiv2026

Spatial engineering of posterior organizers in cerebral organoids via controlled morphogen exposure within hydrogels

Cerebral cortex organoids are powerful in vitro models that recapitulate key features of human development. However, conventional methods produce cortical organoids with spontaneous, spatially disorganized cortical regions due to limited control over morphogen distribution within local environments. Here, we present a spatially engineered hydrogel platform that drives localized posterior organizer formation in cortical organoids through controlled, localized exposure to morphogens. Using a combination of bulk photopolymerization, thermal crosslinking, and digital light processing (DLP) approaches, we fabricated hydrogels with stiffness-controlled layers that preferentially deliver morphogens to one side of the organoid, selectively inducing posterior organizer formation on the exposed face. We further validated this platform by delivering fluorescently tagged dextran, used as molecular weight-matched model morphogens, to visualize spatiotemporal delivery dynamics at the organoid interface. As a proof of principle, we also demonstrated that DLP fabrication enables the printing of dual morphogen hubs, serving as a model for establishing two opposing gradients within a single organoid. Together, this hydrogel platform enables systematic spatial patterning of cell populations in organoids, more faithfully recapitulating the spatial organization and cellular diversity of native tissues and advancing higher-fidelity models for studying human development and disease.

bioengineering↗

bioRxiv2026

Cardiac-Detargeted MyoAAV Enables Systemic Nrl-Mediated Fast Myofiber Remodeling and Hypertrophy Across Multiple Skeletal Muscles

Inducing fast myofiber programs offers therapeutic potential for skeletal muscle disorders such as sarcopenia, where fast myofibers are preferentially lost. Engineered muscle-specific AAV (MyoAAV) vectors enable efficient transduction of skeletal muscles after systemic administration; however, cardiac transgene expression limits applications requiring skeletal muscle-selective delivery. We generated modified MyoAAV vectors by incorporating cardiac-specific miR-208a target sequences into the transgene 3'UTR. This design markedly suppressed cardiac expression while preserving skeletal muscle output, with target-site variation enabling tunable trade-offs between cardiac detargeting and skeletal muscle expression levels. We validated this platform using neural retina leucine zipper (Nrl), a large Maf transcription factor regulating type IIb myofiber identity. Systemic delivery of conventional MyoAAV-Nrl caused severe cardiac hypertrophy and uniform lethality within one month. Conversely, incorporating miR-208a target sequences prevented detectable hypertrophy and eliminated mortality during the experimental observation period. This modification significantly reduced cardiac Nrl expression while maintaining skeletal muscle levels, successfully promoting type IIb myofiber formation and hypertrophy across multiple skeletal muscles. These findings demonstrate that miR-208a-mediated cardiac detargeting combined with MyoAAV-Nrl enables safe systemic induction of fast myofiber remodeling and hypertrophy, establishing a platform for gene therapies targeting skeletal muscle disorders associated with fast myofiber loss.

cell biology↗

bioRxiv2026

Plagl2 unlocks the latent regenerative potential of Müller glia in the adult mouse retina

Muller glia (MG) in the adult mammalian retina have long been recognized as a potential endogenous source for the regeneration of lost retinal neurons. However, existing MG reprogramming strategies yield an incomplete regenerative response by favoring either proliferation or neurogenic differentiation. Here, we show that the zinc-finger transcription factor Plagl2, which has been demonstrated to rejuvenate aged neural stem cells, was sufficient to reprogram adult mouse MG into a progenitor-like state with coupled proliferative and neurogenic competence. Using histology, time-lapse imaging, and single-cell transcriptomics, we found that Plagl2 drove regulated rounds of MG cell cycle re-entry, while N-methyl-D-aspartate-induced retinal injury further promoted the acquisition of neurogenic competence toward inner nuclear layer neuronal identities. These findings identify Plagl2 as a novel rejuvenator of mammalian MG and support the general principle that reprogramming modules can be redeployed across cell types, offering new avenues for unlocking regenerative potential in otherwise non-regenerative tissues.

neuroscience↗

bioRxiv2026

Identification of a pharmacokinetic interaction between teicoplanin and sulfo-butyl ether-β-cyclodextrin, an excipient in the intravenous posaconazole formulation

Patients undergoing hematopoietic stem cell transplantation (HSCT) often receive multiple antibiotics and antifungals concurrently, making it crucial to understand their potential pharmacokinetic interactions of these agents. We report here an interaction between the glycopeptide antibiotic teicoplanin (TEIC) and sulfo-butyl ether-{beta}-cyclodextrin (SBECD), a solubilizing excipient in the intravenous formulation of posaconazole (PSCZ). We performed a single-center retrospective analysis of patients who underwent HSCT and received oral and intravenous PSCZ during TEIC therapy. The associations between PSCZ administration and TEIC concentration-to-dose (C/D) ratios were evaluated using linear mixed-effects models. We also examined the effects of intravenous PSCZ and SBECD on TEIC pharmacokinetics in rats by assessing the area under the concentration-time curve (AUC) and urinary excretion of total TEIC and its components. In addition, molecular docking and in vitro protein-binding assays were conducted to investigate the interaction between TEIC and SBECD. In patients who underwent HSCT, TEIC C/D ratio was significantly lower following intravenous PSCZ administration than without administration. In contrast, the effect of oral PSCZ administration relative to non-administration was not statistically significant. In rats, intravenous PSCZ and SBECD decreased the AUC of TEIC and increased urinary excretion, particularly in the A2 group. Docking simulations indicated that the hydrophobic side chain of TEIC A2-2 fit within the SBECD cavity, and in vitro assays confirmed SBECD concentration-dependent increases in TEIC unbound fractions. The co-administration of intravenous PSCZ containing SBECD may reduce TEIC protein binding, thereby enhancing renal excretion.

pharmacology and toxicology↗

bioRxiv2026

Radiocesium Uptake in Two Fungal Bed-cultivated Edible Mushroom Species in Forests in Fukushima, Japan

In Japan, mushrooms have long been valued as food resources, but the Fukushima nuclear accident disrupted production and shipment due to radiocesium contamination. Limited knowledge has particularly hindered outdoor fungal bed cultivation. To address this, we conducted cultivation experiments with Lyophyllum decastes and Lepista nuda across 14 broad-leaved deciduous forest sites in Fukushima Prefecture. Air dose rates at 1 m height ranged from 0.04 to 0.89 {micro}Sv/h. Radiocesium concentrations (combined 137Cs and 134Cs, expressed as Bq/kg at 90% water content) in fruit bodies were 0.4-12 (mean 2.3) for Ly. decastes and 0.2-43 (mean 8.1) for Le. nuda. Both species remained below Japans food safety threshold of 100 Bq/kg, indicating that safe cultivation is feasible across broad areas. Uptake patterns differed: concentrations in Ly. decastes correlated with contamination in litter and multiple soil layers, whereas in Le. nuda it correlated only with litter contamination. These findings suggest that clean soil fills for Ly. decastes and clean litter covers for Le. nuda could serve as mitigation strategies tailored to each species. Aggregated transfer factors (2.76 x 10-5 m2/kg for Ly. decastes and 6.60 x 10-5 m2/kg for Le. nuda) were lower than those reported for wild mushrooms. Overall, this study provides new insights into reducing radiocesium assimilation by cultivated mushrooms and supports the revival of outdoor fungal bed cultivation in contaminated landscapes.

ecology↗

bioRxiv2025

Robust scoring system to evaluate animal well-being in murine orthotopic breast cancer and ovarian cancer models

Orthotopic models are critical to the development of new cancer therapies, as they have the greatest potential to mimic human cancer progression. However, orthotopic models are often underutilized due to practical challenges. These challenges include the need for specialized surgeries and the presence of complicating symptoms, such as ascites fluid accumulation in ovarian cancer and liver disease models, as well as ulceration of breast tumors growing in the mammary fat pad. An adaptable, quantitative animal health assessment system that utilizes simple, non-invasive, visual measurements can allow researchers to use these models to their full potential while safeguarding humane endpoints. The goal of this work was to establish such health scoring systems for translationally-relevant ovarian (ID8 Defb29-Vegf-A) and breast cancer (triple-negative model 4T1) models. We developed a tractable health assessment system by monitoring a combination of activity and responsiveness, coat condition, respiratory function, changes in body weight, posture, gait, tumor size (where measurable), and extent of ulceration, and scoring each of these parameters using a simple numerical scale. The scores at which euthanasia or other interventions were required were estimated and then adjusted based on clinical assessment by a team of researchers and veterinarians. These semi-quantitative health scoring systems were applied to survival experiments, in which mice were euthanized at a predetermined score or upon meeting a superseding health criterion, to confirm their applicability and effectiveness in maintaining humane endpoints. The scoring systems presented are intended to build on previously-established generic tumor model scoring systems that do not accommodate for the particular phenotypes present in orthotopic breast and ovarian cancer models.

cancer biology↗

bioRxiv2025

Tegmental atrophy in isolated REM sleep behaviour disorder: Ex vivo-informed in vivo imaging

Isolated rapid eye movement (REM) sleep behaviour disorder (iRBD) is an early-stage synucleinopathy characterized by brainstem pathology. In rodents, the pontine tegmentum contains an REM sleep centre, the sublaterodorsal nucleus (SLD), which expresses corticotropin-releasing hormone binding protein (CRHBP). While the involvement of brainstem pathophysiology is thus implicated in iRBD, its solid evidence remains scarce in humans due to the difficulty in identifying small brainstem nuclei with conventional MRI technology alone. Here, we aimed to detect tegmental atrophy in iRBD with voxel-based morphometry (VBM) analysis combined with a novel human brainstem atlas. Structural MRIs from 98 patients with iRBD and 114 controls were analysed to investigate grey matter volume (GMV) using VBM. Our unique approach involved detailed assessments of the VBM results, guided by a high-resolution MRI-based atlas of the human brainstem. This brainstem atlas was founded on ex vivo MRI of 10 postmortem human specimens. We validated it with CRHBP immunostaining, which aided in identifying putative REM sleep-regulating nuclei in humans. We applied this brainstem atlas to identify atrophy in specific brainstem regions in iRBD and correlate their volumes with clinical measures, including autonomic functions. VBM revealed a focal cluster of grey matter atrophy in the dorsal pontine tegmentum of iRBD patients, including the laterodorsal tegmental nucleus, ventral part (LDTgV) and the pedunculopontine tegmental nucleus (PTg). Our atlas-based analysis confirmed the LDTgV as the site of most conspicuous atrophy, revealing a significant volume reduction in iRBD patients compared to controls with a moderate effect size (Cohens d = 0.46, Bonferroni-corrected p = 0.019). Furthermore, greater atrophy in the LDTgV and the PTg was associated with more severe autonomic dysfunction as measured by Scales for Outcomes in Parkinsons Disease-Autonomic dysfunction (SCOPA-AUT) scores (partial r = -0.237, p = 0.019 and partial r = -0.236, p = 0.019, respectively). Histological analysis confirmed that the LDTgV is selectively enriched with CRHBP-positive neurons, a putative marker for REM sleep-on neurons. We provided novel evidence for the involvement of LDTgV, the putative human homolog of the murine SLD, in iRBD. The present findings advance our understanding of the neuroanatomical basis of iRBD and will contribute to the development of early biomarkers for -synucleinopathies.

neuroscience↗

bioRxiv2025

Characterisation of cold-selective lamina I spinal projection neurons

Skin cooling is detected by primary afferents that express the Trpm8 channel, but how this information is conveyed to the brain remains poorly understood. We have previously identified a population of lamina I projection neurons belonging to the anterolateral system (ALS) that receive numerous contacts from Trpm8-expressing primary afferents. Here, using a semi-intact somatosensory preparation, we provide evidence that these cells correspond to the cold-selective ALS neurons identified in previous physiological studies. We also confirm the presence of synapses from Trpm8 afferents onto these cells at the ultrastructural level and with optogenetics. Based on our previous transcriptomic findings, we identify calbindin as a molecular marker, and show that this can be used to target the cold-selective ALS neurons for anterograde tracing studies. We provide evidence that they project to brain regions that have been implicated in thermosensation: the rostralmost part of the lateral parabrachial area, the caudal part of the periaqueductal grey matter, and the posterior triangular and ventral posterolateral nuclei of the thalamus. Our findings provide important insights into the organisation of neuronal circuits that underlie thermoregulation and the perception of cold stimuli applied to the skin.

neuroscience↗

bioRxiv2025

Structural basis for color tuning and passive ion conductance in red-shifted pump-fold channelrhodopsin ChR024

ChR024 is a cation-conducting channelrhodopsin with a red-shifted absorption spectrum, recently discovered from a previously unidentified clade through machine-learning-guided gene mining. Due to its unique position in the phylogenetic tree and distinctive spectral properties, it serves as an important model for elucidating rhodopsin evolution and for engineering optogenetic tools with enhanced performance, but its structure and function remain poorly understood. Here, we present cryo-electron microscopy structures of ChR024 in detergent micelles and lipid nanodiscs at resolutions of 3.22 and 2.45 [A], respectively. The structures reveal an architecture strikingly similar to that of ion-pumping rhodopsins, even more so than other pump-like channelrhodopsins such as ChRmine. Structural, theoretical, and spectroscopic analyses uncover a unique color-tuning mechanism, in which charged residues close and distant from the retinal chromophore cooperatively modulate the pKa of the Schiff base counterion and thereby determine the absorption maximum wavelength. Finally, comparative structural analysis of channel- and pump-type rhodopsins, combined with electrophysiology, provides insights into the molecular boundary between these two functional classes and demonstrates the conversion of an outward proton pump into a light-gated channel. Together, these findings illuminate diverse mechanisms of color tuning and functional specification within the rhodopsin family, paving the way for the rational engineering of next-generation optogenetic tools.

biophysics↗

bioRxiv2025

Functional characterization of red-shifted rhodopsin channels from giant viruses explored by a machine-learning model for long-wavelength optogenetics

Channelrhodopsins (ChRs) are light-gated ion channels. These proteins are widely used in optogenetics to optically manipulate neural activity. However, manipulation using short-wavelength light to activate ChRs causes cell toxicity and is hampered by low tissue penetration. To overcome these difficulties, although several red-shifted ChR variants have been identified, further red-shift is required for more efficient and noninvasive neural control. While molecular screening of ChRs requires high-cost experiments, recent machine-learning-based protein functionality prediction enables more efficient selection of target proteins for characterization. Here, we constructed an elastic-net machine-learning model trained on 1,163 experimental data to predict the maximum absorption wavelength ({lambda}max) of uncharacterized ChRs. The model suggested several red-shifted candidates, and we identified a viral rhodopsin channel, ChR024, with the second-longest{lambda} max as a cation-conducting ChR ({lambda}max = [~]578 nm) after Chrimson ({lambda}max = [~]580 nm). This result demonstrates the high impact of ML on reducing the screening costs of functional proteins.

biophysics↗

bioRxiv2025

Morphogen-guided neocortical organoids recapitulate regional areal identity and model neurodevelopmental disorder pathology

The human neocortex exhibits characteristic regional patterning (arealization) critical for higher-order cognitive function. Disrupted arealization is strongly implicated in neurodevelopmental disorders (NDDs), but current neocortical organoid models largely fail to recapitulate this patterning, limiting mechanistic understanding. Here, we establish a straightforward method for generating arealized organoids through short-term early exposure to anterior (FGF8) or posterior (BMP4/CHIR-99021) morphogens. These treatments created distinct anterior and posterior signaling centers, supporting long-lasting polarization, which we validated with single-cell RNA sequencing that revealed area-specific molecular signatures matching prenatal human cortex. To demonstrate the utility of this platform, we modeled Fragile X Syndrome (FXS) in organoids with distinct anterior and posterior regional identities. FXS organoids showed highly disrupted SOX4/SOX11 expression gradients along the anterior-posterior axis, consistent with alterations found in autism spectrum disorder (ASD) and demonstrate how regional patterning defects may contribute to NDD pathology. Together, our study provides a robust platform for generating neocortical organoids with anterior-posterior molecular signatures and highlights the importance of modeling NDDs using experimental platforms with neuroanatomic specificity.

developmental biology↗

bioRxiv2025

Cell-cell communication as underlying principle governing color pattern formation in fishes

The diverse pigmentation patterns of animals are crucial for predation avoidance and behavioral display, yet mechanisms underlying this diversity remain poorly understood. In zebrafish, Turing models have been proposed to explain stripe patterns, but it is unclear if they apply to other fishes. In anemonefish (Amphiprion ocellaris), we identified gja5b, a gene orthologous to zebrafish leopard and encoding a connexin involved in pigment cell communication, as responsible for the Snowflake phenotype. Using CRISPR/Cas9 and transgenesis, we recapitulate the Snowflake phenotype and show expression of gja5b in iridophores. A matching allele was recovered in zebrafish, revealing complementary requirements in both species. Our findings highlight conserved roles of gap junction mediated communication in pigment patterning across divergent teleosts.

developmental biology↗

bioRxiv2025

Fetal reversion from diverse lineages sustains the intestinal stem cell pool and confers stress resilience

Plasticity is a central mechanism underlying the robust regenerative capacity of the intestinal epithelium. Two major plasticity have been described: spatial plasticity, in which differentiated cells revert to crypt base columnar cells (CBCs), and fetal reversion into revival stem cells (revSCs). However, the relationship among these two stem cell populations and differentiated cells remains to be clarified. Here, we demonstrated the bidirectional interconversion between CBCs and revSCs. Using lineage tracing, injury models and villus culture, we show that absorptive enterocytes can reprogram into revSCs and regenerate CBCs. These findings position fetal reversion as an entry point to spatial plasticity, establishing a regenerative hierarchy where CBCs, revSCs, and enterocytes collectively orchestrate intestinal repair. Furthermore, we identified revSCs as a highly stress-tolerant stem cell population, whose emergence is crucial for preserving the stem cell pool. Our results establish fetal reversion as a cellular escape mechanism safeguarding epithelial regeneration under inflammatory conditions.

cell biology↗