Biology subjects

Hayashi, Y.

Publications and source records attributed to Hayashi, Y..

At least 19 recordsLinked to original sources

bioRxiv2026

Epithelial to mesenchymal transition and M2 macrophages drive aggressiveness in murine and human sarcomatoid urothelial carcinoma.

Patients with majority variant subtype histology including sarcomatoid urothelial carcinoma (SUC) have poor outcomes and limited treatment options, and there are few preclinical resources to investigate rare histologic subtypes. We developed three novel variant subtype histology bladder cancer (BC) cell lines by finding that basal BC tumor cells derived from mice treated with N-butyl-N-(4-hydroxybutyl)-nitrosamine (BBN) were initially not competent to grow in immune competent mice, but then acquired tumorigenicity following passaging (recycling) in mice lacking mature B and T cells. Three genitourinary oncology pathologists identified BBN966 as SUC, BBN964 as a hybrid between SUC and squamous, and BBN975 as squamous, and each had unique growth characteristics. Using a publicly available dataset and our spatial transcriptomics analysis of a cohort of human tumors with mixed SUC and UC as comparators, we found that consistent with human SUC, BBN966 lack expression of basal and luminal genes. Consistent with human SUC and spatial transcriptomics analysis of canine SUC, BBN966 had the highest epithelial to mesenchymal transition (EMT) upregulation, and all three recycled tumor cells had increased EMT pathway expression in recycled tumor cells. Moreover, increased expression of genes upregulated in all three recycled tumor cells associated with worse overall survival in patients with muscle invasive UC. Similar to human SUC, BBN966 tumors had higher proportion of M2 macrophage gene expression. Finally, we found in the largest cohort of PD-L1 IHC to date that 20 of 38 (52.6%) human SUC had CPS > 50, which was driven mostly by tumor proportion score. Consistent with this, we found anti-PD1 immune checkpoint inhibitor (ICI) significantly inhibited BBN966 tumor growth, while the hybrid BBN964 tumors had mixed response to ICI. Thus, the murine BBN966 tumors exhibited similarities to human SUC, and can be used to examine novel therapies for translation into future SUC clinical studies.

cancer biology↗

bioRxiv2026

Sex Differences in Aortic Remodeling During Blood Pressure Reduction Following Gradual Hypertension Development in Spontaneously Hypertensive Rats

BackgroundCardiovascular disease risk is higher in men than in women. Although sex differences in aortic wall adaptation following antihypertensive treatment have been reported in acute hypertension models, the response after gradually developing hypertension, which mimics human essential hypertension, remains unclear. This study investigated sex differences in aortic wall adaptation following acute blood pressure reduction after gradually developing hypertension. MethodSeventeen-week-old spontaneously hypertensive rats (SHRs) were assigned to the Hypertensive group or the antihypertensive (Reversal) group (N = 5/sex each). The Reversal group received the antihypertensive drug captopril for 4 weeks to maintain systolic blood pressure below 130 mmHg. Age-matched Wistar Kyoto rats (N = 3/sex) served as normotensive (Normal) group. After the experimental period, arterial wall thickness, circumferential wall stress, smooth muscle cell phenotype, and histological changes were evaluated. ResultsAntihypertensive treatment significantly reduced systolic blood pressure in both sexes. Both male and female SHRs exhibited elevated circumferential wall stress during the gradual development of hypertension. In females, antihypertensive treatment significantly reduced medial thickness compared with the Hypertensive group, whereas males showed no reduction. Circumferential wall stress in female Reversal group did not differ significantly from either the Hypertensive or Normal group, whereas males exhibited a significant reduction in circumferential wall stress compared with the Hypertensive group. Furthermore, the reduced collagen area fraction in the Hypertensive group returned to the normotensive levels only in females following antihypertensive treatment. ConclusionThese findings indicate that vascular remodeling induced by gradually developing hypertension is more effectively reversed by antihypertensive treatment in females than in males.

bioengineering↗

bioRxiv2026

Environment-specific mechanosensing preserves a common bleb-based migratory program across diverse embryonic environments

Cell migration frequently requires cells to traverse tissue environments with distinct physical and biochemical properties. How migrating cells preserve a common migratory program while adapting to these heterogeneous environments remains poorly understood. Here, we show that chick primordial germ cells (PGCs) preserve a common bleb-based migratory mode throughout embryogenesis despite migrating through mechanically distinct tissues. PGCs formed membrane blebs during both intravascular crawling and migration through the dorsal mesentery. However, nuclear envelope (NE) unfolding and activation of the NE-cPLA2 pathway occurred specifically during migration through the mechanically confined dorsal mesentery, where this pathway was required for bleb formation and efficient migration. In contrast, bleb formation during vascular crawling occurred independently of the NE-cPLA2 pathway, demonstrating that distinct molecular mechanisms can generate the same migratory behavior in different tissue environments. Together, these findings suggest that diverse environmental cues converge on a conserved bleb-forming machinery. We propose a hierarchical model in which migrating cells preserve a common migratory program by flexibly switching the upstream molecular mechanisms that initiate bleb formation according to the tissue environment.

developmental biology↗

bioRxiv2026

Increased Interstitial Flow and Elastic Lamina Degradation Precede Aortic Dissection

AimsTo elucidate the relationship between interstitial flow (IF) and structural changes in the aortic media during the development of aortic dissection (AD). MethodsApolipoprotein E-deficient (ApoE[-/-]) mice infused with angiotensin II (AngII) were used as an AD model, in which AD develops exclusively in the thoracoabdominal aorta but not in the thoracic aorta. To capture characteristics present prior to AD onset, the duration of AngII infusion was shortened to generate Pre-AD group. Normal C57BL/6 mice (Normal group) and ApoE(-/-) mice without AngII infusion (Control group) were also included for comparison. Thoracic and thoracoabdominal aortas were excised from all groups, and IF was measured in vitro in accordance with our previously established methods. ResultsIF velocity was generally smaller than 4 m/s across all groups; however, velocities exceeding 4 m/s was observed predominantly in the thoracoabdominal region of the Pre-AD group. Although mean IF velocity did not differ significantly among groups, the standard deviation differed significantly and was the highest in the thoracoabdominal region of the Pre-AD group. In this region, IF velocity tended to increase with more prolonged AngII administration, indicating acceleration of IF prior to AD onset. Three-dimensional internal structural microscopy revealed fragmentation of the elastic lamina (ELs) and a reduction in elastin density only in the thoracoabdominal region of the Pre-AD group. ConclusionsOur findings suggest that increased IF and EL degradation occur in parallel and together contribute to the initiation of AD.

bioengineering↗

bioRxiv2026

Structural mechanism of the type IX Retron-Kva2 anti-phage defense system

Retrons are prokaryotic genetic elements that protect bacterial cells from invading phages. The type IX retron comprises a non-coding RNA, a reverse transcriptase (RT), and dual effectors: a putative HEPN nuclease and a winged helix-turn-helix (WH) protein. Here, we show that the type IX retron system from Klebsiella variicola cleaves host rRNAs and tRNAs upon phage infection, mediating anti-phage defense via an abortive-infection mechanism. Cryo-electron microscopy analysis reveals that the RT, HEPN, and WH proteins, along with multicopy single-stranded DNA (msDNA), form a unique, sheet-like supermolecular complex. Notably, the HEPN active site is encircled by the WH and msDNA within the complex, suppressing the nuclease activity prior to phage infection. A phage-encoded exonuclease cleaves the msDNA, likely releasing the HEPN nuclease to cleave host RNAs and induce growth arrest in infected cells. Overall, these findings highlight the structural and functional diversity of prokaryotic anti-phage defense systems.

biochemistry↗

bioRxiv2026

Disruption of CaMKII biomolecular condensation induces attention-deficit/hyperactivity disorder-like phenotypes

CaMKII is a multifunctional kinase essential for synaptic plasticity and memory formation. While its canonical role involves enzymatic phosphorylation, recent evidence suggests CaMKII also functions through liquid-liquid phase separation (LLPS) with substrate proteins, including GluN2B-containing NMDA receptors. However, the physiological significance remains unclear. Here, we generated CaMKII subtype knock-in (KI) mice carrying a point mutation (I205K) in the hydrophobic pocket, a key interface required for LLPS. These mice exhibited a complete loss of structural long-term potentiation (sLTP) despite normal spine morphology, marked hyperactivity and profound deficits in aversive memory formation. Atomoxetine, an approved attention-deficit/hyperactivity disorder (ADHD) treatment, ameliorated the hyperactive phenotype. Notably, we identified a patient carrying the I205N variant presenting with ADHD and mild intellectual disability, mirroring the behavioral features observed in I205K KI mice. Additional neurodevelopmental disorder-associated variants within the same hydrophobic pocket similarly disrupted LLPS in vitro. Molecular dynamics simulations revealed these variants destabilize the CaMKII-GluN2B interaction through distinct mechanisms that perturb the dynamic stability of the binding interface. These findings establish CaMKII-mediated phase separation as critical for linking synaptic molecular assembly to cognitive function and provide a unifying molecular basis for synaptic disorganization, hyperactivity, and memory deficits associated with neurodevelopmental disorders. SignificanceCaMKII is essential for synaptic plasticity and memory, yet the contribution of its non-catalytic functions, including liquid-liquid phase separation (LLPS), to brain function remains unclear. Here, we show that disrupting CaMKII LLPS with its synaptic partners impairs synaptic localization, abolishes LTP, and causes profound memory deficits in vivo. A knock-in mouse carrying the I205K mutation showed hyperactivity and impaired learning. This recapitulate the clinical phenotypes of a human patients with the I205N variant, which is associated with ADHD and intellectual disability. Together, these findings establish LLPS as a critical mechanism underlying CaMKII function in the brain and provide a disease-relevant framework for understanding synaptic dysfunction in neurodevelopmental disorders.

neuroscience↗

bioRxiv2026

Next Generation TB Drug Combinations from the Pan-TB Consortium: Combination Efficacy and Contributions of Individual Agents, Evaluated in a BALB/c Mouse TB Model

The Project to Accelerate New Treatments for Tuberculosis (PAN-TB) aims to accelerate development of shorter, simpler and safer pan-TB combinations. We previously identified 3 out of 25 first-generation novel PAN-TB 4-drug combinations, that cured 90% of mice in less than 3 months, at clinically relevant doses in the relapsing mouse model of TB. These regimens include BPa830Sut, BPa286Sut and BQSut286 (B: bedaquiline; Pa: pretomanid; 830: GSK3211830; 286: GSK2556286; Sut: sutezolid; Q: quabodepistat). Here, we assess the efficacy of these combinations where the original candidates are substituted next-generation or more advanced compounds (ganfeborole (656) for 830, sorfequiline, S for B, TBD09 for Sut and TBD11 for 286) and the individual contributions of specific agents. Six novel regimens demonstrated bactericidal activity more rapid than comparators PHMZ (Rifapentine P, Isoniazid H, Moxifloxacin M, Pyrazinamide Z) and BPaMZ. Modelled cure/relapse data showed that SPa286Sut, SPaSut and SPa656Sut cured 90% of mice in about 1 month, while SPa286, SPaQTBD11 and SPaTBD09 in less than 2 months, faster than PHMZ. Consistent with our previous findings, the fastest-curing regimens centered on a diarylquinoline (S), a nitroimidazole (Pa) and an oxazolidinone (TBD09 or Sut) together with an Rv1625c agonist (TBD11 or 286), DprE1 inhibitor (Q) or a LeuRS inhibitor (656). Notably, significant contributions to sterilizing efficacy were demonstrated for S in all combinations and for Pa, Sut, TBD09, Q and TBD11 or 286 in specific S-containing combinations. These findings suggest potential for these novel agents and combinations to improve treatment of both DS-and DR-TB.

pharmacology and toxicology↗

bioRxiv2026

In-cell structures visualize human pre-ribosome assembly in the nucleolus

Ribosome biogenesis is an essential multi-step process. In eukaryotes, it is orchestrated within the nucleolus, a hallmark multi-layered compartment of the nucleus. Structures of pre-ribosomes have been characterized in vitro, but their assembly pathways within human nucleoli have not been described. Here, we used cryogenic correlative light and electron tomography to visualize the molecular landscapes within HeLa cell nucleoli and obtained in-cell structural snapshots of both ribosomal subunit precursors, the SSU processome and the pre-60S. These recapitulate major states resolved previously in vitro while additionally revealing critical interaction partners, including the RNA exosome, rixosome, and nuclear export receptor CRM1-RanGTP. We further show how pre-ribosome assembly is altered upon RNA polymerase I inhibition. Our study combines molecular structures with cellular context to elucidate the spatiotemporal assembly pathways and regulation of human ribosome biogenesis.

cell biology↗

bioRxiv2026

dCBP-mediated histone lactylation contributes to meiotic chromosome maintenance.

Histone lactylation is a recently identified histone post-translational modification (PTM) that links energy metabolism to chromatin regulation. Although histone lactylation has been implicated in transcriptional activation, its function in meiotic chromatin remains unclear. Previously, we identified enrichment of multiple histone lactylation marks within the meiotic karyosome, a highly condensed and transcriptionally repressive chromatin structure formed in Drosophila oocytes. Here, through an RNAi-based screen, we identified the CBP family protein dCBP as a regulator of histone lactylation in the karyosome. Germline-specific knockdown of dCBP preferentially reduced histone lactylation, including H4K8 lactylation, and caused premature disruption of the synaptonemal complex, abnormal egg chamber development with excess nurse cells, reduced egg production, and decreased embryonic viability. Corresponding histone acetylation marks were comparatively less affected than histone lactylation by dCBP knockdown. Together, our findings provide evidence that dCBP-mediated histone lactylation contributes to meiotic chromosome maintenance and suggest a potential link between energy metabolism and meiotic chromatin regulation.

developmental biology↗

bioRxiv2026

Nonclinical pharmacokinetics and relative efficacy of the first 25 novel tuberculosis drug combinations from the PAN-TB consortium: Use of the BALB/c relapsing mouse model and combination pharmacokinetics within a modeling-based framework

The Project to Accelerate New Treatments for Tuberculosis (PAN-TB) aims to accelerate development of shorter, simpler and safer pan-TB combinations, effective for use in both Drug Susceptible (DS)- and Drug Resistant (DR)- TB patients. Towards this aim, bactericidal and sterilizing activity of 25 priority 4-drug combinations was evaluated at doses targeting clinically relevant exposures, in the BALB/c relapsing mouse model of TB. The combinations comprised 8 PAN-TB drugs and candidates: bedaquiline (B), pretomanid (Pa), delamanid (Del), quabodepistat (Q), sutezolid (Sut), GSK2556286 (286), GSK3211830 (830) and ganfeborole (GSK3036656, (656)). Combination PK studies in infected mice enabled dose selection and a population-PK approach guided dosing so that compounds should achieve mean AUC0-24 within 2-fold of their clinical target exposures during the efficacy studies. All test combinations showed time-dependent bactericidal activity, with six regimens reducing lung bacterial burdens below the limit of detection with 8 weeks treatment, similar to the comparator BPaMZ (M is moxifloxacin and Z as pyrazinamide). Cure/Relapse data were modelled to derive population time to cure 90% mice (T90) values. Fifteen PAN-TB combinations had T90s of less than 5 months, sterilizing mice faster than the standard of care for drug susceptible TB, RHZE/RH. The best-performing PAN-TB combinations, BPa830Sut, BPa286Sut and BQSut286, cured 90% of mice in less than 3 months. These 3 top-ranked 4-drug combinations are all centered on a diarylquinoline (B)/oxazolidinone (Sut) core, together with the nitroimidazole (Pa) or a DprE1 inhibitor (Q) plus a novel agent such as the LeuRS inhibitor (830) or the Rv1625c agonist (286).

microbiology↗

bioRxiv2026

Folate-dependent one-carbon metabolism controls meiotic and post-meiotic epigenome remodeling in the male germline

Environmental exposures can influence offspring health through epigenetic alterations in the male germline. Folate deficiency, a dietary perturbation that disrupts one-carbon metabolism and S-adenosylmethionine (SAM) production, has been linked to altered histone methylation and developmental abnormalities in offspring. However, when and how folate availability shapes the germline epigenome during spermatogenesis remains unclear. In this study, unbiased metabolomic profiling of spermatogenic cells uncovers stage-specific metabolic remodeling, including downregulation of serine- glycine-one-carbon (SGOC) metabolism in meiotic spermatocytes. Using a post-weaning folate-deficient mouse model, we investigate how folate availability influences germline epigenome establishment during spermatogenesis. Consistent with this metabolic transition, genome-wide chromatin accessibility profiling demonstrates extensive, stage-dependent remodeling under folate-deficient conditions, particularly in meiotic spermatocytes and post-meiotic spermatids. These accessibility changes display cell-type-specific genomic distributions and preferential localization to repressive chromatin compartments in post-meiotic cells. Histone modification analyses further reveal bidirectional redistribution of the active histone mark H3K4me3 in round spermatids. Although genome-wide distribution of the repressive mark H3K27me3 remains largely stable, folate deficiency alters its nuclear organization. Notably, a subset of H3K4me3 alterations established in post-meiotic cells is retained in mature sperm, providing a mechanistic link between paternal metabolic perturbation and the germline epigenome. Together, these findings demonstrate that folate availability shapes germline epigenome establishment through stage-specific metabolic and chromatin remodeling during spermatogenesis, revealing a metabolic basis for paternal environmental effects on the germline epigenome.

developmental biology↗

bioRxiv2026

Rice Jumonji706 confers the photoperiod sensitivity in rice by distinct regulation of short-day and long-day flowering time regulatory pathways.

Photoperiod sensitivity (PS) is a key biological response in plants as they adapt to specific environments. Rice (Oryza sativa L.) exhibits a clear PS, as it implements critical phase transition decisions based on PS signals. In this study, we identified a novel PS gene, JMJ706, that is expected to deliver photoperiod-related signals to the flowering-time regulatory network in a day-length-dependent manner. The JMJ706 mutants exhibit early flowering under LD and later flowering under SD compared to WT plants. The gene encodes an H3K9me2 demethylase, and under long-day (LD) conditions, its demethylase activity facilitates the expression of Grain number, Plant height, and Heading-date7 (Ghd7). Since Ghd7 is a floral repressor in LD, it promotes the vegetative phase by delaying flowering. Under short-day conditions (SD), H3K9me2 demethylase activity facilitates Early heading-date 1 (Ehd1) expression, and it acts as a floral accelerator by inducing Heading date 3 (Hd3a) and RICE FLOWERING LOCUS T 1 (RFT1). Furthermore, we propose that the daylength-dependent promotion of target genes (Ghd7 and Ehd1) occurs through demethylation of specific promoter regions at a crucial time window. In addition, JMJ706 may play an important role in regulating plant architecture, including plant height. The natural variation in JMJ706 alleles shows high frequencies across major rice subpopulations, suggesting that JMJ706 could play an important role in the geographical distribution and adaptation of rice cultivars. Our results may add a new layer to the rice flowering-time regulatory pathway, supporting regional adaptation and potential for future breeding.

plant biology↗

bioRxiv2025

EC-isHCR: a rapid method for in situ hybridization chain reaction in diverse animal samples

The in situ hybridization chain reaction (isHCR) visualizes RNA across multiple spatial scales, from organs to subcellular structures, in diverse samples. We previously proposed a rapid protocol, EC-isHCR, for Drosophila embryos and ovaries. Whether EC-isHCR retains the features of conventional isHCR, including wide-spatial-scale analyses in various samples, however, has remained unclear. Here, we show that EC-isHCR enables robust RNA detection in a broad range of samples, such as whole-mount fruit fly, parasitoid wasp, and aphid preparations; paraffin sections of trout; frozen mouse sections; and human cultured cells. Moreover, EC-isHCR enabled detection of subcellular RNA localization. EC-isHCR also visualized co-localization of RNA with phase-separated condensates in fruit fly embryos and detected the protrusion-enriched mRNA in HeLa cells. To broaden the applicability of EC-isHCR, we developed an automated probe design tool (https://github.com/ShuntaYorimoto/hcrkit). By combining this tool with EC-isHCR, we provide a fast and versatile framework to visualize mRNAs. This framework will help reduce the barrier to using fast isHCR and thereby facilitate research across diverse areas of the life sciences. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=77 SRC="FIGDIR/small/696653v1_ufig1.gif" ALT="Figure 1"> View larger version (25K): org.highwire.dtl.DTLVardef@1852584org.highwire.dtl.DTLVardef@621682org.highwire.dtl.DTLVardef@1b3bf5corg.highwire.dtl.DTLVardef@1d86841_HPS_FORMAT_FIGEXP M_FIG C_FIG Highlights- EC-isHCR enables rapid acquisition of high-contrast images. - EC-isHCR preserves features of conventional isHCR, including versatile sample compatibility and high-resolution imaging. - An automated probe design tool was developed for EC-isHCR. - EC-isHCR/probe tool framework will help reduce the barrier to using fast isHCR.

bioengineering↗

bioRxiv2025

Roles of a Drosophila ADAM 10 transmembrane metalloprotease, Kuzbanian, in tissue architecture and function of the adult adipose tissue

Various molecular mechanisms in mature adipose tissue regulate whole-body physiology. In contrast, our current understanding of the development of this tissue is limited. The adult fat body (AFB) of Drosophila melanogaster is an emerging model for investigating the regulatory mechanisms of adipose tissue morphogenesis in vivo. AFB precursor cells undergo long-range directional and collective migration, proliferation, and homotypic adhesion, leading to the formation of monolayered AFB during metamorphosis. Here, we show that a Drosophila ADAM10 transmembrane metalloprotease, Kuzbanian (Kuz), is required for the AFB morphogenesis in the precursor cells at the onset of adhesion. Histological and ultrastructural analyses revealed that the kuz knocked-down AFB cells formed multilayered structures or clumps, indicating that Kuz is essential for forming a single-cell-thick tissue sheet. Furthermore, adults with the morphologically altered AFB were supersensitive to starvation stress. Finally, we tested the hypothesis that Notch (N), a well-characterized substrate for Kuz or ADAM10, participates in AFB development, and found that knocking down N reduced AFB area coverage and made the adults less adaptive to starvation, similar to kuz knockdown. Altogether, our study highlights the critical role of Kuz in both the architecture and function of adult adipose tissue.

developmental biology↗

bioRxiv2025

Sox4 in Treg Cells Suppresses IL-10 Production via c-Maf Degradation and Exacerbates Type 2 Inflammation

The anti-inflammatory cytokine interleukin-10 (IL-10) produced by regulatory T (Treg) cells plays a crucial role in regulating allergic airway inflammation. However, the mechanisms governing IL-10 production in Treg cells remain unclear. In this study, we first identified Sox4 as a gene whose expression is down-regulated in IL-10-producing Treg cells. Comprehensive gene expression profiling of Sox4-deficient Treg cells and Sox4-overexpressing Treg cells revealed specific downregulation of Il10 and Ctla4 by Sox4. Sox4-deficient Treg cells exhibited increased IL-10 production and CTLA-4 expression both in vitro and in vivo and strongly suppressed Th2 cell proliferation compared with Sox4-expressing Treg cells. In a house dust mite (HDM)-induced asthma model, Treg-specific Sox4-deficient (Sox4-cKO) mice exhibited IL-10-dependent reductions in eosinophilic inflammation and Th2 cell infiltration in the airways. A comparison of Sox4-cKO and wild-type Treg cells in the same inflamed environment in mixed bone marrow chimeric mice with HDM-induced asthma revealed that Sox4-mediated suppression of c-Maf is cell-intrinsic. In addition, overexpression of Sox4 in Treg cells repressed the activation of c-Maf-regulated chromatin regions, including those around the Il10 and Ctla4 loci. Moreover, Sox4-induced suppression of IL-10 and CTLA-4 in Treg cells was rescued by forced expression of c-Maf. While Sox4 did not significantly affect Maf mRNA levels, Sox4 degraded c-Maf proteins in Treg cells through its 33 C-terminal residues. Via a domain distinct from its C-terminus, Sox4 physically interacted with c-Maf, subsequently facilitating its degradation through a ubiquitin-proteasome pathway. These findings elucidate a mechanism by which Sox4 influences the asthmatic responses by regulating the c-Maf/IL-10 axis in lung Treg cells.

immunology↗

bioRxiv2025

Bleb-based extravasation: conserved morphodynamics, divergent calcium control

Extravasation, the exit of cells from blood vessels, is essential in both development and disease, from germ cell migration to cancer metastasis. We show that all extravasating cells examined, avian primordial germ cells and diverse human cancer lines, form Ca{superscript 2}-dependent membrane blebs during transendothelial migration. Yet the source of Ca{superscript 2} diverges by lineage. PGCs and HT-1080 fibrosarcoma cells rely on store-operated Ca{superscript 2} entry (SOCE), whereas epithelial cancer cells such as PC-3 and MDA-MB-231 use IPR-mediated Ca{superscript 2} release from the endoplasmic reticulum. These findings establish bleb-based extravasation as a conserved morphodynamic strategy powered by distinct regulatory modules. Evolutionarily, they map onto an ancestral ER-release pathway and a metazoan-derived SOCE pathway. Conceptually, cancer blebbing emerges as a composite strategy that reactivates both ancient survival programs and developmental toolkits to maximize invasive success. This unified framework highlights Ca{superscript 2} supply as a critical bottleneck of vascular escape, offering new angles for targeting metastatic dissemination.

cell biology↗

bioRxiv2025

Maternal care during early development is necessary for the acquisition of a calming response to back stroking

In many mammals, early postnatal interactions between caregivers and offspring involve rich physical contact, including stroking, holding, and grooming. Offspring typically remain calm and close to the caregiver during such stimulation. Although these behaviors are thought to support emotional regulation and bonding during infancy, the underlying mechanisms and the role of prior experience remain unclear. Here, we demonstrate that back stroking induces a conserved calming response in both human infants and mouse pups, characterized by reduced movement and heart rate. In mouse pups, stroking further facilitated sleep onset, increased EEG delta power, and attenuated stress-induced corticosterone elevations. These sleep-promoting and stress-buffering effects were absent in artificially reared pups deprived of postnatal maternal contact, underscoring the importance of early tactile experience. Transcriptomic analysis revealed downregulation of the voltage-gated calcium channel subunit gene Cacna1b in the hypothalamus of artificially reared pups. Moreover, knockdown of hypothalamic Cacna1b in maternally reared pups abolished stroking-induced calming and sleep-promoting effects. This study identifies a conserved, experience-dependent calming response to affiliative tactile input, biologically embedded through plasticity, that supports physiological regulation and stress resilience during early development. Our results highlight that affiliative tactile sensation, like discriminative tactile sensation, depends on early experience to organize neural mechanisms regulating internal states. SignificanceEarly-life physical contact with caregivers is essential for healthy emotional and physiological development in mammals, but its underlying mechanisms remain unclear. We show that back stroking induces a conserved calming response in both human infants and mouse pups, reducing movement, heart rate, and promoting sleep. These effects depend on early tactile experience and are mediated by Cacna1b expression in the hypothalamus. Our findings identify a plastic, experience-dependent pathway through which affiliative tactile input modulates internal states, revealing how parental care supports stress resilience and sleep physiology during early development.

neuroscience↗

bioRxiv2025

Ki-67 shapes the nucleolus by anchoring chromatin via its amphiphilic properties

The nucleolus, a membrane-less organelle essential for ribosome biogenesis, adopts variable shapes across cell types and in response to environmental conditions, yet the mechanisms regulating its morphology and functional implications remain unclear. Using a high-throughput screen, we identify the proliferation marker Ki-67 as a central regulator of nucleolar shape. Ki-67 localises to the chromatinnucleolus interface, where its depletion induces nucleolar rounding and reduces chromatin enrichment within and around the nucleolus. This effect is driven by amphiphilic properties conferred by two distinct affinity domains separated by a spacer. Given that chromatin loss is a common feature of rounded nucleoli in our screen, and acute chromatin digestion also induces rounding, we propose that the chromatin environment in and around the nucleolus plays a key role in determining nucleolar shape. Our study elucidates a novel Ki-67-mediated chromatin anchoring mechanism, tightly linking nucleolar shape to genome organisation and expanding our understanding of condensate morphology.

cell biology↗