Biology subjects

Wu, J.

Publications and source records attributed to Wu, J..

At least 199 records · Page 11Linked to original sources

bioRxiv2025

Contribution of the lateral extension of the hyporheic zone in gravel bars in shaping river invertebrate diversity

Gravel bars (GBs) and hyporheic zone (HZ) are two major natural geomorphic features in gravel-bed rivers, having multiple functions ranging from habitat provisioning to nutrient cycling. This study examines whether the lateral extension of HZ in GBs contributes to the total diversity of river aquatic invertebrates. The hyporheic invertebrate community composition was entirely dissimilar from the benthic habitat, with stable GB hyporheic location exhibiting a more distinct community composition compared to wetted channel and active GB across all seasons. The local contribution to beta diversity (LCBD) also showed that stable GB has significantly higher uniqueness across all seasons, indicating a more unique invertebrate community. Species contribution to beta diversity (SCBD) indicates that this uniqueness was mainly driven by hyporheic dwelling species amphipod, Pseudocrangonyx yezonis, and Isopod species. Distance from wetted channel and dissolved oxygen were the factors influencing hyporheic invertebrates distribution. These findings show that the maintenance and restoration of gravel bars are crucial to enhancing and maintaining the overall invertebrate diversity in the river ecosystem.

zoology↗

bioRxiv2025

Discovery of chromatin-based determinants of azacytidine and decitabine anti-cancer activity

The DNA-incorporating nucleoside analogs azacytidine (AZA) and decitabine (DEC) have clinical efficacy in blood cancers, yet the precise mechanism by which these agents kill cancer cells has remained unresolved - specifically, whether their anti-tumor activity arises from conventional DNA damage or DNA hypomethylation via DNA methyltransferase 1 (DNMT1) inhibition. This incomplete mechanistic understanding has limited their broader therapeutic application, particularly in solid tumors, where early clinical trials showed limited efficacy. Here, through the assessment of drug sensitivity in over 600 human cancer models and comparison to a non-DNA-damaging DNMT1 inhibitor (GSK-3685032), we establish DNA hypomethylation, rather than DNA damage, as the primary killing mechanism of AZA and DEC across diverse cancer types. In further support of an epigenetic killing mechanism, CRISPR drug modifier screens identified a core set of chromatin regulators, most notably the histone deubiquitinase USP48, as AZA and DEC protective factors. We show that USP48 is recruited to newly hypomethylated CpG islands and deubiquitinates non-canonical histones, establishing USP48 as a key molecular link between the two components of epigenetic gene regulation: DNA methylation and chromatin modification. Furthermore, loss of USP48, which occurs naturally through biallelic deletions in human cancers, sensitized both hematologic and solid tumors to DNMT1 inhibition in vitro and in vivo. Our findings elucidate the epigenetic mechanism of action of AZA and DEC and identify a homeostatic link between DNA methylation and chromatin state, revealing new therapeutic opportunities for DNMT1 inhibitors in solid tumors.

cancer biology↗

bioRxiv2025

Gene signatures characterizing driver mutations in lung squamous carcinoma are predictive of the progression of pre-cancer lesions

Patients with lung squamous cell carcinoma (LUSC) are often diagnosed at advanced stages, limiting opportunities for early intervention. LUSC develops through a multistep progression from low-grade lesions to high-grade lesions, including carcinoma in situ (CIS), of which approximately half progress to invasive cancer while the other half regress. Although frequent mutations and copy number alterations have been documented in LUSC and observed in precursor lesions, their prognostic significance in precancerous stages remains largely unexplored. In this study, we leveraged gene expression data from LUSC tumors in The Cancer Genome Atlas (TCGA) to derive transcriptional signatures corresponding to 34 key driver genomic aberrations, including mutations, amplifications, and deletions. These tumor-derived gene signatures were then applied to precancerous lesion datasets to assess their ability to characterize developmental stages and predict progression risk. We found that many of these signatures increased progressively across lesion stages, reflecting their roles in early tumorigenesis. In particular, several signatures accurately predicted which CIS lesions would progress to invasive cancer. Furthermore, these signature scores were more strongly associated with patient prognosis in LUSC than the presence of genomic aberrations alone. We also examined the relationship between driver-associated signatures and the tumor immune microenvironment. Signature scores were significantly correlated with immune features such as immune cell infiltration and immune checkpoint gene expression, including CD274 (PD-L1). Interestingly, these associations varied across lesion stages, indicating dynamic immune interactions during cancer evolution. Together, our findings demonstrate that tumor-derived driver gene expression signatures provide valuable insight into the biology and progression risk of precancerous lesions, offering potential utility for early detection and intervention strategies in LUSC. Novelty and ImpactIn this study, we developed gene expression signatures using lung squamous cell carcinoma (LUSC) transcriptomic and genomic data and apply them to characterize precancerous lesions. These signatures showed high performance in predicting the progression risk of carcinoma in situ (CIS), offering a valuable tool for personalized prevention and early intervention in LUSC. These findings have the potential to improve early lung cancer detection and provide new insights into the tumor microenvironment in the context of precancer evolution of LUSC.

bioinformatics↗

bioRxiv2025

APOE knockout attenuates vascular graft fibrosis by limiting profibrotic macrophage formation through low-density lipoprotein receptor related protein 1

Vascular graft fibrosis can cause a decrease in cellular infiltration and capillary ingrowth in vascular walls and vascular stiffening. As such, there are still no vascular grafts that can be used in blood vessels where their diameters are less than 6 mm in patients. Although various approaches have been evaluated to mitigate implant-associated fibrosis, effective treatments remain quite limited. In this study, we demonstrated that APOE was significantly increased during vascular regeneration after graft implantation in vivo. APOE knockout (KO) increased compliance of regenerated aortas and reduced extracellular matrix (ECM) deposition in adventitia of the regenerated aortas. Using single cell RNA sequencing (scRNA-seq), a subset of profibrotic macrophages was found to be involved in graft fibrosis and APOE KO limited the formation of profibrotic macrophage formation during vascular regeneration. The interaction between APOE and low-density lipoprotein receptor related protein 1 (LRP1) partially mediated fibrotic differentiation of the macrophages. Profibrotic macrophages promoted graft fibrosis mainly through secretion of insulin-like growth factor-1 (IGF-1) that could support proliferation of fibroblasts. Finally, we showed that APOE knockdown in vivo using adeno-associated virus (AAV) improved the compliance of regenerated aortas and reduced ECM deposited in the adventitial areas by limiting formation of profibrotic macrophages. Collectively, these data indicate that APOE promotes the profibrotic transition of macrophages partially through LRP1, and the profibrotic macrophages increase the proliferation of fibroblasts via IGF-1. Inhibition of APOE by AAV can alleviate graft fibrosis occurring during vascular regeneration.

bioengineering↗

bioRxiv2025

PP2A activation drives aberrant macropinocytosis and cell death in pancreatic ductal adenocarcinoma

Pancreatic cancer is highly aggressive with a five-year survival rate of just 13%. Metabolic rewiring in response to oncogenic signals plays a critical role in pancreatic ductal adenocarcinoma (PDAC) survival, tumor growth, and metastasis. These alterations make PDAC tumors dependent on anabolic metabolism for survival, highlighting a unique vulnerability that can be therapeutically exploited. However, during nutrient deprivation, PDAC cells can circumvent this vulnerability by engulfing extracellular fluids to replenish amino acids in a process called, macropinocytosis. This process can be induced downstream of oncogenic KRAS expression, a small GTPase that is almost universally mutated in PDAC patients. The inhibition of macropinocytosis in vivo reduces PDAC tumor growth, emphasizing the importance of this pathway to cancer cell survival. However, the signaling mechanisms that regulate this process remain poorly understood. Protein phosphatase 2A (PP2A) is a heterotrimeric complex that regulates a wide variety of cell signaling pathways, including KRAS, and is commonly dysregulated in human PDAC tumors. Here, we show that acute PP2A activation prevents macropinosome processing leading to cell death. Furthermore, we demonstrate that PP2A posttranslationally regulates the lipid kinase, PIKfyve, a key regulator of macropinosome-lysosome fusion. Finally, we determine that PP2A activating compounds can function synergistically with metabolic inhibitors, supporting a new therapeutic strategy in this aggressive and deadly cancer. Together, our results implicate PP2A as a critical suppressor of PDAC metabolic plasticity and highlight the use of PP2A activating compounds to prevent PDAC nutrient scavenging.

cancer biology↗

bioRxiv2025

Generative cerebral vasculature visualization using spatialtranscriptomic data

The brain is sustained by an intricate vascular network that provides a continuous supply of nutrients and oxygen essential for its function. Understanding the structural variability and region-specific function of this neurovascular system is essential for interpreting neurological alterations in disease models. Leveraging the spatial mRNA-guided generative model Tera-MIND (simulating Tera-scale Mouse braINs using a patch-based and boundary-aware Diffusion model), we propose to predict the spatial organization of brain vasculature by the co-expression patterns of Cldn5 and Acta2 genes and their learned attention map at cell-level resolution. These findings demonstrate the capability of generative AI models trained on single-cell spatial transcriptomic data to reconstruct biologically meaningful higher-order structures. They highlight the potential of such models as in silico systems - GenAI-based simulations that generate realistic representations of biological architecture from spatial molecular data - for high-throughput exploration of vascular function and its dysregulation in neurological disorders. Taken together, our approach repurposes existing spatial transcriptomics datasets to derive new spatial insights into vascular organization, without the need for additional tissue processing. Significance StatementThe brains vascular network is complex and functionally essential. Accurate reconstruction of this network at single-cell transcriptomic resolution is key to understanding neurovascular disorders. This study applies spatial transcriptomic and histological data to generate representations of brain vasculature using Tera-MIND, providing a framework that offers a scalable approach for understanding vascular organization.

neuroscience↗

bioRxiv2025

Targeting DNA-LNPs to Endothelial Cells Improves Expression Magnitude, Duration, and Specificity

DNA-lipid nanoparticles (DNA-LNPs) loaded with inhibitors of the cGAS-STING pathway enable safe and effective delivery of DNA in vivo. Herein, we report the first instances of extrahepatic DNA-LNP targeting. DNA-LNPs conjugated to antibodies against PECAM-1 or VCAM-1 target the endothelium of the lungs and brain/spleen, respectively. These LNPs drive robust transgene expression in their target organs, with greater magnitude and duration than untargeted LNPs. Lung specificity of PECAM-targeted transgene expression increases over two weeks, resulting in markedly higher lung-to-liver expression ratios than our previous PECAM-targeted mRNA-LNPs. Off-target liver DNA expression declines to undetectable levels but persists in the lungs, while mRNA expression uniformly decreases due to its short half-life. We further improve this expression specificity by replacing full-length antibodies with Fab fragments. Single-cell analysis reveals a key mechanism underlying the improvements in organ-specificity: target organ expression is dominated by long-lived endothelial cells, while off-target liver delivery and expression are in non-endothelial cells with shorter half-lives. Collectively, these studies demonstrate that targeted DNA-LNPs achieve high levels of organ- and cell-type-specific transgene expression and thus provide a therapeutic platform for dozens of endothelial-centric diseases.

bioengineering↗

bioRxiv2025

Pluripotent stem cell-derived siTNK cells attack tumors via a synthetic CD8-CD28 TCR complex

Tumor-associated antigen-specific T cell receptor (TCR)-engineered T cells offer a promising strategy for cancer therapy. Natural killer (NK) cells exhibit broad anti-tumor activity with low side effects but lack the capacity to recognize intracellular antigens. Here, we found that the human pluripotent stem cell (hPSC)-derived iNK cells, unlike tissue-isolated NK cells, expressed all four CD3 subunits at the transcriptome level. We introduced a synthetic gene-expressing complex (SCOTR), encoding a tumor antigen- specific TCR, CD8 coreceptor, and CD28 costimulatory molecule, into hPSCs to generate SCOTR-hPSCs. The SCOTR-hPSCs gave rise to abundant synthetic TCR complex-expressing iNK (siTNK) cells via an organoid induction method. These siTNK cells showed HLA-dependent, antigen-specific cytotoxicity against tumor cells and significantly suppressed tumor growth in tumor xenograft animal models, while also preserving universal non-specific tumor-killing activity. Collectively, siTNK cells, as hPSC-derived hybrid cells with dual features of adaptive T and inherent NK cells, offer an artificial cell source for human immunotherapies.

immunology↗

bioRxiv2025

AAV-based temporal APOE4-to-APOE2 replacement reveals rebound adaptation and RAB24-mediated Aβ and cholesterol dysregulation

APOE-targeted gene therapy offers a promising strategy for modifying Alzheimers disease (AD) risk, yet the temporal dynamics and context-dependent effects of APOE isoform modulation remain poorly defined. Here, we developed a rapid AAV-based platform enabling inducible in vivo replacement of APOE4 with APOE2. In 5xFAD mice, sustained APOE4 expression exacerbated cognitive decline, A{beta} deposition (parenchymal and vascular), and glial activation, whereas long-term APOE2 expression--with concurrent APOE4 silencing--significantly reversed these pathological features and rescued cognitive function. In contrast, short-term APOE2 replacement conferred no benefit and unexpectedly worsened behavioral and pathological outcomes. Transcriptomic profiling revealed that APOE4-associated gene signatures were broadly reversed by long-term APOE2 expression, but paradoxically aggravated by short-term replacement. Among these, RAB24--a regulator of autophagic trafficking--was upregulated by APOE4 and short-term APOE2 but suppressed by long-term APOE2. RAB24 elevation impaired A{beta} clearance and cholesterol homeostasis via lysosomal retention in primary astrocytes and neurons. Together, these findings uncover a rebound-adaptation mechanism that shapes APOE2 therapeutic outcomes, identify RAB24 as a modifiable node in A{beta} and cholesterol metabolism, and establish a temporally controlled gene therapy platform to inform the design of future APOE-targeted interventions in AD.

neuroscience↗

bioRxiv2025

A Compact Two-Photon Module for Simultaneous Dual-Depth, Multi-Region in vivo Brain Imaging

Understanding how distributed brain regions interact across cortical depths is crucial for uncovering the neural basis of behavior and cognition. Two-photon microscopy (2PM) excels at imaging the superficial layer, while three-photon microscopy (3PM) penetrates deep tissues but lacks sufficient speed for capturing fast superficial dynamics. Here, we present a compact two-photon imaging module (2PIM) that seamlessly integrates with existing 3PM to achieve simultaneous, high-speed imaging of superficial and deep brain regions, while preserving the deep tissue penetration of 3PM. This dual-modality system allows for remote and independent control of imaging planes in both axial and lateral dimensions. Leveraging this technology, we discovered context-dependent modulation of hippocampal CA1 and visual cortex responses to identical tactile stimuli, layer-specific temporal dynamics in sensory cortex during air puff stimulation, and depth-divergent neuronal activity patterns in motor cortex across acute-to-chronic pain. These results highlight the systems potential for dissecting the spatiotemporal coordination of distributed brain circuits.

bioengineering↗

bioRxiv2025

Cortex-Wide, Cellular-Resolution Volumetric Imaging with a Modular Two-Photon Imaging Platform

Mapping cortex-wide neuronal activity at single-cell resolution has been limited by the physical trade-off between numerical aperture and field-of-view (FOV) in two-photon microscopes. We present Meso2P, a modular two-photon platform that decouples excitation and detection by introducing a lateral paraboloid fluorescence collector. The design sustains an effective NA 0.87 over a contiguous 6 x 6 mm2 FOV at high speed (2,048 x 2,048 pixels at 7.67 Hz). The modular platform can be upgraded with optional modules for simultaneous multi-plane imaging (1-4 planes at full resolution and speed), volumetric imaging (6 x 6 x 0.5 mm3, 2,048 x 2,048 x 28 voxels at 1 Hz capturing> 210,000 neurons), and holographic two-photon optogenetic stimulation for targeted perturbations. To handle the resulting large-scale data, we provide an open-source deep-learning pipeline that automates motion correction, segmentation, and spike inference. We demonstrate cortex-wide sensory responses, layer-specific network synchrony during anaesthesia, and in-vivo tracking of micro and nanoplastic distribution. Meso2P therefore provides a reproducible route to high-throughput volumetric imaging across almost the entire cortex with high detection efficiency.

neuroscience↗

bioRxiv2025

Perturbation Recovery Time Identifies Subtle Human Balance Impairments and Features

Falls are a leading cause of injury and growing healthcare costs, particularly in aging populations. However, early-stage balance impairments often remain undetected until severe problems arise. Quantitative assessment of human balance therefore remains a critical challenge. Here, we introduce Perturbation Recovery Time, a novel state-space-based balance metric inspired by nonlinear dynamic system theory that quantifies the duration required for gait dynamics to consistently return to a steady-state neighborhood following a perturbation. Unlike conventional approaches based on steady-state walking, this framework evaluates balance through externally induced perturbations that reveal control mechanisms not observable during unperturbed gait. Using healthy participants with experimentally induced impairments, we identified key balance-related features, including the anterior-posterior center-of-mass-center-of-pressure distance, whole-body angular momentum in the frontal and sagittal planes, and vertical center-of-mass position and acceleration. These features capture the core mechanisms of balance control, including foot placement, inverted pendulum dynamics, push-off control, and trunk regulation. Perturbation Recovery Time reliably detected within-subject changes in balance associated with controlled impairments in sensory input, motor coordination, and movement consistency. These findings demonstrate that Perturbation Recovery Time provides a quantitative and sensitive measure of balance, offering a framework for early detection of balance impairments.

bioengineering↗

bioRxiv2025

Precision culturomics enabled by unlabeled single-cell morphology and Raman spectra

Selective enrichment of target bacteria from complex communities such as the human microbiome has remained a challenge. Here we report a solution based on morphology, Raman spectrometry and the Laser-Induced Forward Transfer technology, which works at microbial single cells, many generations before they appear as colonies. We develop a machine learning-based framework that enables species-level targeted sorting of single microbial cells from complex microbiome. We illustrate the utility of this approach in selecting for or against specific bacteria in fecal microbiome samples and the potential for quantifying the molecules expressed based on Raman spectra. Analysis of single-cell cultured genomes reveals that brief antibiotic use drives both pre-existing resistance and de novo mutations in the transpeptidase or efflux pumps of gut commensals, along with convergent evolution between different species. Our precision culturomics method should enable detailed morphological, metabolic, and genomic insights into variations in microbial phenotypes at the single-cell level for microbiome studies.

microbiology↗

bioRxiv2025

HSF4: A Prognostic Predictor and Potential Therapeutic Target in Colorectal Cancer with Implications for Patient Immune Status

Colorectal cancer (CRC) is among the most prevalent malignancies globally, characterized by high morbidity and mortality rates. The Heat Shock Factor (HSF) family of genes plays a critical role in the cellular response to environmental stress, particularly heat stress. These genes encode transcription factors that regulate the expression of heat shock proteins, which are essential for maintaining cellular homeostasis under stressful conditions. Recently, there has been a growing interest in the role of HSF family genes in the development and progression of CRC. In this study, we conducted a comprehensive analysis of CRC samples from The Cancer Genome Atlas (TCGA) database to identify potential therapeutic targets. A total of 533 gene expression matrices, were downloaded and processed, including 42 normal and 491 tumor samples. Differential expression analysis of the HSF family genes, revealed HSF4 as the most significantly differentially expressed gene between normal and tumor samples. Consequently an HSF4-related signature was constructed, stratifying all CRC patients in the TCGA dataset into low-risk or high-risk groups based on HSF4 expression. Survival analysis demonstrated a significant association between HSF4 expression and clinical outcomes indicating that the signature possesses substantial. Correlation analysis further revealed significant relationships between HSF4 expression and clinical features including Stage, T stage, M stage, and N stage. Univariate and multivariate Cox regression analyses confirmed the prognostic significance of HSF4. Functional analysis of differentially expressed genes based on HSF4 expression levels demonstrated enrichment in critical biological processes and pathways. Furthermore, HSF4 exhibited unique properties within the tumor microenvironment (TME). Additional analysis indicated that different risk groups exhibit varying levels of immune cell infiltration and cell proliferation capacity. Notably, the low-risk group showed increased sensitivity to multiple chemotherapeutic agents due to its lower IC50 values. In conclusion, this study presents the first signature for predicting the prognosis and immunological status of CRC patients based on HSF family genes. Our findings suggest that HSF4 may serve as a potential therapeutic target in CRC.

cancer biology↗

bioRxiv2025

Electric fields trigger ceramide-dependent budding of exosome vesicles into multivesicular endosomes and boost the generation of exosomes

Exosomes hold immense therapeutic and diagnostic potential, yet their clinical translation remains constrained by low yields. Physiological electric fields (EFs), naturally occurring during wound healing and embryo development, have unexplored roles in exosome biogenesis. Here, we demonstrate that physiological-strength EFs (Direct Current, 50-200 mV/mm) dramatically enhance cellular exosome secretion, achieving a nearly 100-fold increase in a strength-dependent manner. Mechanistically, EFs augmented intraluminal vesicle formation within multivesicular bodies. We proposed a novel EF-driven membrane electroassembly and vesiculogenesis hypothesis and tested it using giant plasma membrane vesicles. We reconstructed EF-induced membrane remodeling and observed EFs driving inward budding of nanoscale exosome-like vesicles. Notably, alternating current EFs (50-400 Hz) exhibited significantly diminished efficacy compared to direct current EFs, highlighting membrane electropolarization-dependent modulation. Pharmacological inhibition of the lipid raft and ceramide almost abolishes EF-induced exosome secretion. Inhibition of the PI3K partially attenuated EF-triggered exosome release. Our findings not only unveil EFs as a potent physiological regulator of exosome secretion but also establish a novel, high-yield production strategy leveraging bioelectric cues. Significant statementWe reported that the bodys natural bioelectricity, the faint electric currents in healing wounds and embryo development, can trigger cells to release 100 times more "natural nanoscale vesicle couriers" called exosomes. This pure physical method is far more efficient than current available technologies, paving the way for breakthroughs in cancer early detection, stem cell therapies, and precision medicine. We found that gentle electric fields can "blow" the cell membrane to release exosomes like "soap bubbles". This explains how bioelectricity controls cell communication during development and wound healing. In short, harnessing the bodys hidden "electric language" unlocks a fast and natural way to mass-produce exosomes.

cell biology↗

bioRxiv2025

Rac1 Selectively Binds a Specific Lamellipodin Isoform via a Noncanonical Helical Interface

Lamellipodin (Lpd) is a multifunctional adapter protein that regulates cell migration and adhesion by recruiting Ena/VASP proteins to the leading edge and modulating actin polymerization. The interaction of Lpd and Rho family or Ras family GTPases is crucial for regulating actin dynamics. Contrary to previous assumptions that the main Lpd isoform interacts with Rac1, here we show that strong and specific binding to Rac1 is instead mediated by the short isoform Lpds. This interaction is dependent on Rac1s GTPase activity and a short insertion (cs2) within the coiled-coil (CC) region unique to the Lpds isoform. Structural modeling and mutagenesis analyses further reveal that Lpds engages Rac1 through a noncanonical, single-helix binding mode distinct from the classical helical pair configuration. Our results reveal a novel isoform-dependent GTPase:effector binding mode and suggest a critical regulatory pathway that may represent a promising therapeutic target in Rac1-driven cancer progression.

biochemistry↗

bioRxiv2025

Giant viruses specific to deep oceans show persistent presence and activity

Giant viruses (GVs) of the phyla Nucleocytoviricota and Mirusviricota are large double-stranded DNA viruses that infect diverse eukaryotic hosts and impact biogeochemical cycles. Their diversity and ecological roles have been well studied in the photic layer of the ocean, but less is known about their activity, population dynamics, and adaptive strategies in the aphotic layers. Here, we conducted eight seasonal time-series samplings of the surface and mesopelagic layers at a coastal site in Muroto, Japan, and integrated 18S metabarcoding, metagenomic, and metatranscriptomic data to investigate deep-sea GVs and their potential hosts. The analysis identified 48 GV genomes including six that were exclusively detected in the mesopelagic layer. Notably, these mesopelagic-specific GVs showed persistent activity across seasons. To investigate the global deep-sea-specific GV distribution, we compiled GV reference genomic data from the OceanDNA MAG project and other resources, and analyzed 1,890 marine metagenomes. This revealed 101 deep-sea-specific GVs, distributed across the GV phylogenetic tree, indicating that adaptation to deep-sea environments has occurred in multiple lineages. One clade enriched with deep-sea-specific GVs included one GV identified in our Muroto sampling, which displayed a wide geographic distribution. Seventy-six KEGG orthologs and 74 Pfam domains were specifically enriched in deep-sea-specific GVs, encompassing functions related to the ubiquitin system, energy metabolism, and nitrogen acquisition. These findings support the scenario that distinct GV lineages have adapted to hosts in aphotic marine environments by altering their gene repertoire to thrive in this unique habitat. IMPORTANCEGiant viruses are widespread in the ocean surface and are key in shaping marine ecosystems by infecting phytoplankton and other protists. However, little is known about their activity and adaptive strategies in deep-sea environments. In this study, we performed metagenomic and metatranscriptomic analyses of seawater samples collected from a coastal site in Japan and discovered giant virus genomes showing persistent transcriptional activity across seasons in the deep-sea water. Using a global marine dataset, we further uncovered the widespread existence of deep-sea-specific giant viruses and characterized their unique gene repertoire, which likely facilitates adaptation to the limited availability of light and organic compounds in the aphotic zone. These findings expand our understanding of giant virus ecology in the dark ocean.

genomics↗

bioRxiv2025

Genome-wide analysis reveals mutual gene flow between goats from Island Southeast Asia and from Southern Africa

This study aimed to reveal a comprehensive genetic diversity and genetic structure of Island Southeast Asian (ISEA) goats, and infer the details of gene introgressions and propagation routes in ISEA goats using genome-wide SNPs. Correlation analysis of the distance from the domestication center and the genetic diversity of each Asian population showed a significant negative correlation (r = - 0.796, p = 2.66E-05), while the Philippines showed a relatively high genetic diversity (He = 0.363) against the distance, suggesting the multiple propagation routes and admixture history in Philippine goats. Reduced Representation Admixture Analysis at K=6 showed that six clusters (Europe, Northwest Africa, Southern Africa, Eastern Africa, Asia and Southeast Asia) were formed based primarily on geographical location, and ISEA goats included African and Europe components. However, this introgression is much lower in Indochinese goats. In addition, the Southern African and European populations included Southeast Asia component. Treemix and f4 statistics analyses showed the genetic influence and gene flow between ISEA and the Southern Africa. The results of this study have revealed obvious mutual gene flow between ISEA and the Southern African regions through the European maritime activities across the Indian Ocean since the Middle Ages.

ecology↗