Biology subjects

Guo, L.

Publications and source records attributed to Guo, L..

At least 37 records · Page 2Linked to original sources

bioRxiv2026

Attraction to secreted isoamyl alcohol as a signal for beneficial commensals

C. elegans, a bacterivore living in microbially-complex environments, harbors a characteristic community of gut bacteria that contribute to its health and fitness. What determines which environmental bacteria end up as commensals is largely unknown in C. elegans, as in other animals. Previous work found that gut Pantoea isolates supported rapid worm development and infection resistance, while environmental congenerics were inferior. Notably, worms were preferentially attracted to the more beneficial gut isolates. Using bioactivity-guided fractionation and gas chromatography-mass spectrometry analysis, we identified bacterially derived isoamyl alcohol (IAA) as a secreted volatile attractant underlying this preference. Screening of worm mutants implicated AWC sensory neuron-associated genes in preferential attraction to beneficial Pantoea and established a causal link between IAA sensing and colonization by beneficial strains. While IAA sensing was important for initial colonization, gut-associated Pantoea strains ultimately outcompeted environmental congenerics over time, indicating that microbiome assembly is shaped by two complementary processes: host behavioral preference for high-IAA producers and bacterial competitive fitness within the gut. While IAA is a product of leucine metabolism and may function as a nutritional cue, we found that it could also directly enhance host infection resistance, suggesting an additional role in modulating host physiology. Finally, knockout analysis identified a bacterial branched-chain amino acid aminotransferase homolog as important for IAA production. Together, these findings identify bacterial volatile sensing as an important and underexplored mechanism shaping microbiome composition and its contributions to host fitness.

microbiology↗

bioRxiv2026

GABA antagonises ABA perception and signalling in plants

Abscisic acid (ABA) is a central regulator of plant growth and stress responses. However, it also negatively impact germination, growth, and reproductive performance, highlighting the need for mechanisms that fine-tune its signalling. Here, we identify {gamma}-aminobutyric acid (GABA) as an endogenous antagonist of plant ABA receptor. We show that GABA binds the clade A protein phosphatase-ABI1, disrupting its association with the ABA receptor PYL1, blocking ABA binding, thereby attenuating ABA signalling. GABA modulates ABA-control of stomatal aperture and seed germination, demonstrating its broad physiological influence. Notably, GABA accumulation during stress coincides with the subsequent decline in ABA, consistent with a delayed feedback signal of ABA activity. Together, this work identifies GABA as an antagonist of ABA and provides a mechanism balancing plant stress resilience and growth.

plant biology↗

bioRxiv2026

The Par complex regulates apical-basal cell polarity through modulation of FAK signaling homeostasis

Cell polarity complexes are essential for embryogenesis, but their regulatory mechanisms during early developmental transitions remain incompletely understood. Here, we individually deleted the Crumbs, Par, and Scrib polarity complexes in mouse embryonic stem cells (mESCs). While loss of any single complex did not affect pluripotency or proliferation, deletion of Par complex disrupted the naive-to-primed transition and impaired subsequent differentiation, particularly lumen formation in neural tube organoids. Mechanistically, Par complex deficiency led to hyperphosphorylation of focal adhesion kinase (FAK) at the primed stage, driving a morphological shift from flat monolayer clusters to dome-shaped colonies. FAK inhibition rescued the aberrant morphology. Upstream, Par complex loss increased AKT phosphorylation, which remodeled extracellular matrix (ECM) and regulated integrin signaling via FURIN-LEFTY, ultimately modulating FAK activity. In addition, conditioned medium from wild-type cells partially rescued differentiation defects in Par knockout cells in a LEFTY-dependent manner. These phenotypes were consistently observed in naive-to-primed transition, neural stem cell differentiation, embryoid body formation, teratoma assays, and neural tube organoid differentiation. Together, these findings establish a Par complex-AKT-FURIN-LEFTY-ECM-integrin-FAK signaling cascade that links apical-basal polarity to early lineage specification and morphogenesis, providing a mechanistic framework for how polarity cues are translated into developmental outcomes. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=200 SRC="FIGDIR/small/722465v1_ufig1.gif" ALT="Figure 1"> View larger version (64K): org.highwire.dtl.DTLVardef@179e0adorg.highwire.dtl.DTLVardef@8d83bdorg.highwire.dtl.DTLVardef@c425fforg.highwire.dtl.DTLVardef@19a8ee5_HPS_FORMAT_FIGEXP M_FIG C_FIG Significance StatementThis study elucidates the molecular mechanism by which the Par complex regulates the establishment of cell polarity. The authors demonstrate that the Par complex promotes the expression of the protein convertase FURIN via AKT signaling, thereby enhancing the maturation and secretion of LEFTY protein. This process remodels the ECM and modulates integrin signaling, ultimately regulating FAK activity and controlling the establishment of cell polarity. These findings reveal how polarity cues govern early lineage specification and morphogenesis, with implications across multiple developmental contexts.

developmental biology↗

bioRxiv2026

Cell membrane proteome profiling uncovers molecular signatures and GPCR regulators underlying diet-induced obesity and exercise-mediated adaptation

Cell membrane proteins (CMPs), notably G protein-coupled receptors (GPCRs) and receptor tyrosine kinases (RTKs), represent the largest class of druggable targets. Despite their therapeutic importance, how the CMP landscape is systemically remodeled during metabolic disease progression and in response to exercise remains poorly understood. Here, we constructed the most comprehensive CMP proteome atlas to date across 22 male mouse tissues and established the first multi-tissue map of GPCR-associated protein hormones/prohormones. Integrated CMP proteomic and transcriptomic analysis revealed that diet-induced obesity and its progression to type 2 diabetes remodel the CMP repertoire in patterns distinct from those induced by exercise. We found that numerous GPCRs and RTKs critical for energy homeostasis are dysregulated during obesity in a tissue-specific manner, and these alterations are reversed to varying extents by exercise training. Importantly, our CMP-centric omics study identified two parathyroid hormone receptors (PTHRs) in the hypothalamus as negative regulators of feeding and body weight. Genetically silencing these hypothalamic PTHRs led to severe obesity even on a chow diet and markedly blunted exercise-induced weight loss. Collectively, our study provides not only new insights into systematic CMP regulation underlying metabolic deterioration versus exercise adaptation, but also nominates potential receptor targets for obesity management.

biochemistry↗

bioRxiv2026

Origin and evolution of grapevine genomes

Grapevines (Vitis) belonging to grape family (Vitaceae) are symbolic fruit crops pivotal to human civilization. The evolutionary history of grapevines divergent from other Vitaceae plants remains mysterious, requiring a family-wide whole-genome phylogenomic analysis. Here, we conduct chromosome-level phylogenomics to investigate the origin and evolution of grapevines using 29 genome assemblies of five genera Vitis, Parthenocissus, Ampelopsis, Tetrastigma, and Cissus, 27 of which are newly released in this study. Phylogenomic and macrosynteny analysis unanimously support Ampelopsis as a sister lineage to Parthenocissus, placing both closer to Vitis, with introgression and incomplete lineage sorting contributing to these relationships. Ancestral genome reconstruction delineates the major chromosome rearrangement events in Vitaceae karyotype evolution, highlighting the conserved karyotype in Vitis and the extensive karyotypic reorganization in Tetrastigma and Cissus. Pan-3D genome analysis highlights the contributions of structural variants (SVs) to the variation of A/B compartments and topologically associated domains (TADs), revealing a strong purifying selection of SVs at TAD boundaries. We further demonstrate that Helitron transposons drive the expansion and expression regulation of NLR immune-receptor genes in Vitis. Importantly, we discovered an NLR gene VbRpv35 from wild grapevine V. bellula resistant to downy mildew (DM), whose heterologous expression in V. vinifera confers enhanced DM resistance. Taken together, we provide phylogenomic insight into the origin and evolution of grapevines and valuable resources for grapevine improvement and understanding angiosperm evolution.

genomics↗

bioRxiv2026

Identification of scavenger receptor BI as a scavenger of free heme that is essential for protection against hemolysis

Severe hemolysis is a life-threatening condition with limited therapeutic options. Although haptoglobin and hemopexin sequester hemoglobin and heme, these protective systems are rapidly saturated during acute hemolysis, leading to the accumulation of cytotoxic free heme. In this study, we identify scavenger receptor BI (SR-BI) as a critical mediator of free heme clearance. SR-BI binds heme and facilitates its hepatic uptake under pathological conditions. Mice lacking hepatic SR-BI exhibit impaired heme clearance and increased susceptibility to heme- and hemolysis-induced lethality. Pharmacological upregulation of hepatic SR-BI via imatinib or adenoviral delivery confers protection against heme toxicity. Using a humanized model of sickle cell disease (SCD), we further demonstrate that sickle hepatopathy significantly reduces hepatic SR-BI expression compared to non-SCD littermates, potentially increasing vulnerability to heme-induced injury. Notably, adenoviral-mediated SR-BI upregulation rescues SCD mice from heme toxicity. These findings reveal a previously unrecognized mechanism of heme detoxification via hepatic SR-BI and identify a promising therapeutic target for hemolytic disorders. One-Sentence SummaryIdentification of scavenger receptor BI as a targetable scavenger of heme in hemolysis

physiology↗

bioRxiv2026

Agent-Guided De Novo Design of Nanobody Binders Against a Novel Cancer Target

Therapeutic antibody discovery remains slow and resource-intensive, with traditional methods providing limited control over epitope selection. We present a workflow for de novo nanobody design applied to a novel Desmoplastic Small Round Cell Tumor target encompassing four stages: (1) epitope identification guided by our hotspot recommendation agent using physical chemistry-based structure and sequence analysis tools with two curated databases (IEDB, PFAM), (2) de novo nanobody generation using three independent methods (RFantibody, IgGM, mBER) across multiple predicted antigen structures and nanobody frameworks, (3) multi-metric scoring including structural metrics from folding models, and in silico binding affinity from our sequence-based predictor, (4) high-throughput yeast surface display (YSD) screening followed by surface plasmon resonance (SPR) characterization of the specific binders. We generated 288,000 nanobody designs spanning eight target epitope regions and three variable domains of heavy chain-only antibody (VHH) frameworks. Multi-objective Pareto filtering with our candidate selection agent yielded 100,000 candidates for YSD screening with fluorescence-activated cell sorting (FACS). Of 116 enriched candidates advanced to SPR characterization, 46/116 (39.7%) produced reliable kinetic fits with Rmax [≥] 30 RU, yielding KD values from 0.66 nM to 305 nM (median 31.7 nM). These results show that an agent-guided computational workflow can design nanomolar to sub-nanomolar nanobody binders against a novel target without experimental structure or prior antibody information.

bioinformatics↗

bioRxiv2026

REST-AKT-SOX2 axis controls neuronal lineage state and Midkine-mediated communication in SHH-medulloblastoma.

Stem/progenitor-like cells are known drivers of tumor progression, chemoresistance, and relapse in Sonic-Hedgehog medulloblastoma (SHH-MB), yet the regulatory mechanisms that sustain these resilient cellular states remain incompletely defined. Here, we identify the RE1-silencing transcription factor (REST) as a key transcriptional regulator that preserves the progenitor compartment in SHH-MB through stabilization of the stemness factor SOX2. Mechanistically, REST activates AKT signaling, which in turn enhances SOX2 protein stability, revealing a REST-AKT-SOX2 axis that supports stem/progenitor identity and ongoing tumor maintenance. Beyond maintaining intrinsic stem-like programs, REST also orchestrates the extrinsic communication network of SHH-MB tumors. Single cell transcriptomic profiling and ligand-receptor interaction mapping highlight Midkine (MDK)-mediated signaling as one of the most upregulated intercellular communication routes in MB. We demonstrate that REST drives this signaling cascade through its control of SOX2. Perturbation of REST or SOX2 results in reduced MDK and its receptor, SDC2 expression, and chromatin immunoprecipitation assays show that SOX2 directly binds and regulates MDK/SDC2 expression, establishing and reinforcing a REST/SOX2 centered transcriptional mechanism that coordinates both progenitor maintenance and cell-cell communication in the malignant compartment. Together, these findings position REST as an integrator of intrinsic progenitor cell programs and extrinsic MDK-mediated signaling in SHH-MB. By linking stemness, communication and potential for therapeutic resistance, the REST-AKT-SOX2-MDK signaling axis emerges as a targetable vulnerability to suppress stem/progenitor driven tumor program in REST-driven SHH-MBs.

cancer biology↗

bioRxiv2026

The Ser83, Arg85, Tyr88, Asn124, Lys192 of C-terminal Lipid-associated membrane hemagglutinin affecting Mycoplasma synoviae agglutination of erythrocyte

Mycoplasma synoviae is an avian pathogen that causes respiratory disease and synovitis, and its hemagglutinin plays a critical role in host cell adhesion. However, the key residues and structural mechanisms underlying hemagglutination remain unclear. In this study, domain analysis of the hemagglutinin family of Mycoplasma synoviae revealed that it contains long-chain and short-chain types, among which LAM HA (VY93_RS01465) was selected as the bait protein due to its complete C-terminal conserved domain. Through yeast two-hybrid screening, 18 host proteins interacting with LAM HA were identified. Furthermore, five key amino acid residues S83, R85, Y88, N124, and K192 were found to mediate hemagglutination activity. Deletion of these residues reduced the hemagglutination titer of LAM HA under acidic conditions. Secondary structure analysis showed that the deletion mutation decreased the -helix content while increasing the proportions of {beta}-sheet and random coil. Molecular dynamics simulations revealed that the mutant exhibited generally higher root mean square deviation and root mean square fluctuation values than the wild-type under different pH conditions, with a marked decrease in structural stability particularly at pH 5.0 and 6.0. These findings indicate that LAM HA, as a critical adhesin, exerts its hemagglutination function dependent on specific key residues and pH-sensitive conformational stability. IMPORTANCEMycoplasma synoviae (M. synoviae) causes significant economic losses to the poultry industry worldwide. Lipid-related membrane protein hemagglutinin (LAM HA) is a surface adhesin essential for host cell attachment, but its precise amino acid residues and structural features have not been defined. In this study, five key residues (S83, R85, Y88, N124, and K192) were identified as critical for LAM HA-mediated hemagglutination activity. Deletion of these residues altered the secondary structure composition, reduced conformational stability under acidic pH conditions, and decreased hemagglutination activity. These findings reveal a previously unknown structure-function relationship of M. synoviae LAM HA, demonstrating that its hemagglutination activity depends on specific residues and pH-sensitive structural integrity. This provides new insights into the molecular mechanisms of M. synoviae adhesion and offers potential targets for the development of novel intervention strategies against avian mycoplasmosis.

microbiology↗

bioRxiv2026

Integrative Multi-cohort Transcriptomics and Network Pharmacology Analysis Reveals Key Network Nodes and Potential Drug Clues in PCOS Granulosa Cells

BackgroundPolycystic ovary syndrome (PCOS) is a prevalent endocrine disorder with complex pathophysiology and limited therapeutic options. Identifying key molecular drivers and potential drug candidates is critical for improving clinical outcomes. MethodsWe integrated multi-cohort transcriptomics (GSE155489, GSE138518, GSE226146) with weighted gene co-expression network analysis (WGCNA), protein-protein interaction (PPI) network analysis, and drug repurposing. Differential expression analysis identified 1,039 DEGs, and WGCNA identified 10 PCOS-associated modules. Intersection of DEGs with module genes yielded 498 core candidate genes, which were subjected to functional enrichment, PPI network analysis, and connectivity map-based drug repurposing (CLUE/LINCS). Candidate drugs were further evaluated by molecular docking and ADMET prediction using a triple intersection strategy (hub genes, high differential expression, drug-target evidence). ResultsFunctional enrichment revealed significant enrichment in cell adhesion and TGF-beta signaling. PPI network analysis identified CD44 as the top hub gene (degree=42). Drug repurposing identified 106 candidate drugs, including troglitazone and enzalutamide. Using the triple intersection strategy, five genes (ID2, NR4A1, GJA5, ID1, MYH11) were prioritized for molecular docking. GJA5 showed strong predicted binding affinity with flufenamic acid (-7.88 kcal/mol), and cytosporone B exhibited favorable druglikeness (0 Lipinski violations). ConclusionThis study systematically characterizes PCOS-associated gene networks and provides a prioritized set of candidate targets and drugs through a purely computational framework. CD44 emerges as a key network node with potential relevance in PCOS pathophysiology. These findings offer testable hypotheses for future mechanistic studies and drug discovery efforts in PCOS.

systems biology↗

bioRxiv2026

Survey of Climate-structured Mycobiomes in Staple Maize: Implications for Endemic Keshan and Kashin-Beck Diseases

Keshan disease (KD) and Kashin-Beck disease (KBD) are geographically restricted disorders in rural China with overlapping environmental and dietary risk factors. Selenium deficiency alone cannot explain their regional heterogeneity. Maize, a dietary staple in endemic areas, represents a key exposure pathway for climate-sensitive foodborne fungi and their metabolites. We profiled maize-associated fungal communities from seven villages across KD-, KBD-, KD-KBD co-endemic, and non-endemic regions using ITS sequencing and integrative bioinformatics. Fungal diversity, composition, trophic structure, and predicted biosynthetic gene cluster potential differed markedly among regions. KD-endemic areas were enriched in saprotrophic taxa such as Penicillium and Aspergillus, KBD-endemic regions favored cold- and humidity-adapted fungi, and KD-KBD co-endemic areas exhibited the highest predicted mycotoxin potential. Fungal patterns were strongly associated with regional temperature and humidity. These findings support a climate-sensitive, foodborne exposome framework, suggesting that variation in maize-associated fungi may contribute to endemic disease risk and highlighting the need for fungal surveillance in public health strategies. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=115 SRC="FIGDIR/small/716289v1_ufig1.gif" ALT="Figure 1"> View larger version (43K): org.highwire.dtl.DTLVardef@2cf23borg.highwire.dtl.DTLVardef@d31e5aorg.highwire.dtl.DTLVardef@6dbcadorg.highwire.dtl.DTLVardef@7e0734_HPS_FORMAT_FIGEXP M_FIG C_FIG

ecology↗

bioRxiv2026

A widespread gut bacterial lineage distinguished by redox metabolism and phage defense

Genomic variation within gut microbial species can have consequences for host health and disease. However, for low abundance species, these variations can be difficult to capture by both culture-dependent and -independent approaches. Here, we focus on the prevalent but low abundance gut Actinomycetota Eggerthella lenta. We developed a selective media for sensitive and specific isolation of E. lenta from human stool. Genomes from 87 new E. lenta isolates were combined with prior high-quality assemblies, shedding light on within-species functional diversity. Phylogenetic analysis revealed a broadly distributed subclade, which we refer to as E. lenta Group B. This lineage was differentiated by its metabolic potential and bacteriophage defense, though mobile elements were shared broadly across the species. Notably, Group B was positively associated with intestinal inflammation in subjects with inflammatory bowel disease. Overall, these results emphasize the importance of bacterial population structure in host-microbiome interactions and provide a framework to study low-abundance gut taxa. HIGHLIGHTSO_LISelective media enables E. lenta isolation and reveals high prevalence in humans C_LIO_LIDiscovery of a distinctive lineage within E. lenta undergoing genome reduction C_LIO_LIE. lenta Group B has altered metabolism, phage defense, and disease associations C_LIO_LIA widespread conjugative plasmid could enable improved genetics C_LI

microbiology↗

bioRxiv2026

An oxytocin-gated circuit from the hypothalamus silences olfactory tubercle neurons to drive prosocial grooming

Spontaneous helping behaviors such as allogrooming are vital for survival in social species, yet their underlying neural mechanisms remain largely unknown. Although oxytocin (OXT) is known to modulate allogrooming, the precise neural circuits, molecular pathways, and sensory drivers remain unclear. Here, using a social emergency paradigm in mice, we show that observer mice selectively allogroom distressed, anesthetized conspecifics, a behavior that is guided by main olfactory system cues and mitigates the demonstrators anxiety. We identify an oxytocinergic circuit from the paraventricular hypothalamus to the medial olfactory tubercle (PVNOXT[->]mOT) that is necessary and sufficient for this helping behavior. In vivo fiber photometry reveals that PVNOXT[->]mOT activity and OXT release are temporally locked to allogrooming initiation. This behavioral effect requires oxytocin receptor (OXTR) signaling specifically on mOT dopamine D1 receptor-expressing neurons, where OXTRs suppress neuronal excitability via G protein-gated inwardly rectifying K+ (GIRK) channels. Disruption of this inhibitory mechanism induces neuronal hyperexcitability and impairs allogrooming, a deficit rescued by restoring GIRK function. These findings define a PVNOXT-mOT circuit for prosocial helping, revealing an oxytocinergic pathway with potential therapeutic relevance for neuropsychiatric disorders characterized by social deficits.

neuroscience↗

bioRxiv2026

A feed-forward loop between niche adenosine and Gzmk⁺ CD8 T cells propagates systemic inflammaging

The causal link between the aging microenvironment and T cell aging remains elusive. Here, we demonstrate that adenosine within aging tissues actively reprograms CD8+ T cells into a pro-aging Granzyme K+ (Gzmk+) population. Mechanistically, senescent cells create an adenosine-rich niche via p16-dependent CD39 upregulation, triggering A2aR signaling to induce Gzmk+ T cell differentiation. Once released, Gzmk promotes systemic inflammaging through PAR1 and complement activation. Crucially, targeting this axis--either via genetic Gzmk ablation or pharmacological A2aR blockade--reverses multi-organ aging phenotypes and significantly extends healthy lifespan in mice. Human analysis reveals age-dependent Gzmk+ T cell accumulation in multi organs, while coffee intake (an A2aR antagonist) inversely correlates with plasma Gzmk levels. Our findings uncover how metabolic niche changes drive T cell aging and establish the adenosine-Gzmk axis as a pivotal therapeutic target for combating age-related diseases.

immunology↗

bioRxiv2026

Stromal asparagine supports tumor adaptation to oxidative phosphorylation inhibition through SLC38A4-mediated metabolic coupling

PurposePancreatic ductal adenocarcinoma (PDAC) is characterized by a nutrient-deprived and hypoxic tumor microenvironment (TME) that imposes severe metabolic stress on cancer cells. Under these conditions, tumor cells frequently activate the integrated stress response (ISR) to adapt to TME and develop resistance to therapies. However, how TME components support tumor adaptation to mitochondrial metabolic stress remains incompletely understood. Here, we aimed to identify key metabolite involved in ISR adaptation under oxidative phosphorylation (OXPHOS) inhibition and to elucidate the metabolic symbiosis between cancer-associated fibroblasts (CAFs) and PDAC cells. MethodsWe integrated transcriptomic and metabolomic analyses with functional assays. ISR activation was evaluated by assessing the phosphorylation of eIF2 (p-eIF2) following treatment with carboxyamidotriazole orotate (CTO), an Complex I inhibitor. Metabolomic profiling was used to identify metabolites involved in ISR activation alleviation. Mouse models were used to assess therapeutic responses following depletion of the identified metabolite under CTO treatment. Genetic perturbation of Slc38a4 was performed to assess its functional role in tumor cell adaptation to metabolic stress. ResultsWe identified asparagine (ASN) as a critical metabolite supplied by CAFs to PDAC cells under OXPHOS inhibition. A minimum level of ASN is required for PDAC cells to execute ISR downstream adaptation. ASN depletion significantly enhanced the anti-tumor efficacy of OXPHOS inhibition both in vitro and in vivo. SLC38A4 emerged as a potential mediator of this interaction. SLC38A4 expression was associated with c-Myc, and its loss increased the sensitivity of PDAC cells to CTO-induced metabolic stress. ConclusionOur findings reveal a CAF-tumor metabolic crosstalk in which stromal-derived ASN supports PDAC cell adaptation to mitochondrial metabolic stress. Adaptive outcome of ISR signaling depends on the availability of key metabolic substrates such as ASN. When extracellular ASN supply is limited, the ATF4-dependent adaptive program collapses, converting ISR from a pro-survival response into a therapeutic vulnerability. SLC38A4 may function as a key mediator of this metabolic coupling and represents a potential target for enhancing the efficacy of OXPHOS inhibition in PDAC.

cancer biology↗

bioRxiv2026

Exploration of Orally Disintegrating Tablet for Sublingual Vaccination against Mucosal Bacterial Infection

Oral mucosal bacterial infections impose a substantial global disease burden, yet current clinical management typically reduces microbial load only transiently and rarely establishes durable protection at the oral surface. Analysis of 200 patients with periodontitis revealed that elevated levels of pathogen-specific salivary secretory Immunoglobulin A (sIgA) were strongly associated with reduced bacterial burden and improved clinical periodontal outcomes, identifying sIgA as a key determinant of effective oral protection. Guided by this observation, we developed a sublingual, orally disintegrating tablet vaccine (Capot) that incorporates bacterial extracellular vesicles providing a comprehensive repertoire of native antigens and multiple pathogen-associated molecular patterns, encapsulated within a calcium phosphate nanoshell to enable safe transmucosal delivery to submandibular lymph nodes. The rapidly disintegrating tablet format minimizes inadvertent swallowing and enhances local mucosal bioavailability. In mice and non-human primates, Capot induced robust and long-lasting salivary sIgA responses without overt oral mucosal or gastrointestinal inflammation and conferred strong protection against primary, recurrent, and antibiotic-resistant periodontitis. Together, these findings establish sublingual tablet vaccination as a practical strategy for selectively engaging oral mucosal immunity and preventing chronic bacterial diseases at oral mucosal surfaces.

bioengineering↗

bioRxiv2026

Cell Type Architecture and Positional Gene Gradients in an Adult Animal at Subcellular Resolution

The spatial organization of cell types and gene expression underlies tissue architecture and organismal physiology. However, resolving complete cellular and molecular landscapes within a three-dimensional context remains challenging, particularly in organisms with high cellular heterogeneity and complex geometry. Here, we developed a semi-supervised workflow to reconstruct high-resolution three-dimensional spatial transcriptomic models of the planarian Schmidtea mediterranea at single-cell resolution. Planarians are basal bilaterians capable of regenerating body structures after injury. Our reconstruction maps the distribution of cell types and spatially patterned gene expression across the intact organism and identifies 119 candidate positional control genes (PCGs). These genes are expressed across muscle, neural, and epidermal populations. Functional perturbation of selected candidates, including pitx3, ptpn11, pi4ka, upf3b, and cul1, revealed roles in regeneration following injury. In addition, we identify intestinal cells as prominent components of the microenvironment surrounding adult tgs1 pluripotent stem cells (neoblasts). Together, these results demonstrate the utility of three-dimensional spatial transcriptomic reconstruction for mapping cellular architecture and positional gene regulation in complex adult organisms.

developmental biology↗

bioRxiv2026

4D Single-Cell Spatial Transcriptomics Reveals Dynamic Morphogenetic Gradients and Regenerative Domains in Planarians

Regeneration relies on precise spatiotemporal gene expression and cellular responses to establish tissue identity and body patterning. Using high-resolution Stereo-seq (715 nm) on 353 sections from 16 whole animals at 8 regeneration timepoints, we constructed a 4D spatiotemporal transcriptomic map of planarian regeneration. Our analysis captured 36 refined cell types from 3,508,004 segmented cells, enabling genome-wide transcriptional imputation of gene expression dynamics across body axes at cellular, tissue, and organismal scales. We identified dynamic positional gradients and distinct spatially distributed cell types during regeneration, including an injury-induced Anterior Regenerative Zone (ARZ). The ARZ exhibited enriched positional signals in epidermal, muscle, and neural cells and was regulated by Mediator 8, which is crucial for polarity remodeling and blastema formation. This study provides a comprehensive spatial molecular and cellular map of regenerative processes, highlighting injury-induced spatial domains and key regulatory factors in planarian regeneration. We also provide an interactive web portal, offering a valuable resource for exploring and analyzing regeneration mechanisms in a spatiotemporal context.

developmental biology↗