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At least 19 recordsLinked to original sources

[Effects of fungicide on temporal and spatial niches of Rhizoctonia solani].

This paper studied the variation of the temporal and spatial niches of rice sheath blight-causing Rhizoctonia solani under spraying fungicide. The results showed that between fungicide treatments and control, the spatial niche breadth of Rhizoctonia solani was different, while its temporal niche breadth was similar. The spatial niche breadth of Rhizoctonia solani was 0.5240 when spraying fungicide at booting and full heading stages, 0.5742 at booting and milkfilling stages, and 0.8577 at tillering stage, while the control was 0.8563. Spraying fungicide had little effect on temporal niche breath. The spatial niche breath, percentage of diseased leaves and sheathes, index of disease, and control effect all suggested that spraying fungicide two times in rice growth period was better than spraying it one time. Spraying fungicide at booting and full heading stages and at booting stage and milkfilling stages had the best effects. Fungicide could not only narrow the spatial niche breadth, limit the spread of Rhizoctonia solani on top leaves which were important for the yield, but also narrow the temporal niche breadth, limit the spread of Rhizoctonia solani during the yield formation period of rice. But, spraying fungicide only changed the distribution of the fungus niches and narrowed the niches during rice yield formation period, with no changes in the whole niches of Rhizoctonia solani.

Fungicides, Industrial↗

Spatial niche remodeling of senescent liver-resident immune cells and its role in chronic liver diseases.

The liver serves the triple functions of metabolism, detoxification, and immune surveillance. Its unique immune microenvironment is shaped by continuous exposure to gut-derived antigens, pathogen-associated molecular patterns (PAMPs), and metabolites arriving via the portal vein, necessitating a delicate equilibrium between immune tolerance and effector activation. This equilibrium relies on the coordinated activities of diverse liver-resident immune cell populations-including Kupffer cells (KCs), liver sinusoidal endothelial cells (LSECs), hepatic stellate cells (HSCs), dendritic cells (DCs), tissue-resident memory T cells (TRM), innate-like T cells, including mucosal-associated invariant T (MAIT) cells, natural killer T (NKT) cells, and γδ T cells, innate lymphoid cells (ILCs, encompassing conventional NK cells and helper ILC subsets), and neutrophils. With advancing age and chronic injury, these resident immune cell populations undergo profound senescence-associated phenotypic reprogramming that is spatially organized along the portal-to-central axis of the hepatic lobule. Key mechanisms include: telomere dysfunction and DNA damage accumulation driving persistent activation of p53/p21 and p16/Rb pathways; mitochondrial dysfunction with mitochondrial DNA (mtDNA) leakage fueling the senescence-associated secretory phenotype (SASP) via the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) pathway; epigenetic age acceleration, including genome-wide H3K27me3 heterochromatinization; and metabolic reprogramming toward glycolysis and lipid accumulation. This review proposes a "spatial niche remodeling" framework to integrate these cell-intrinsic senescence programs with their lobular context, intercellular communication network rewiring, and pathogenic roles across the spectrum of chronic liver disease-from steatosis through steatohepatitis, fibrosis, cirrhosis, to hepatocellular carcinoma. We critically evaluate emerging senotherapeutic strategies targeting specific liver-resident immune cell subsets, discuss the barriers to clinical translation, and identify priority areas for future investigation, including the application of spatial multi-omics, humanized models, and epigenetic clock-guided clinical trials.

Kupffer cells↗

Integrated single-cell and spatial transcriptomic analyses reveal malignant epithelial glycolytic heterogeneity and spatial niche remodeling during colorectal cancer progression.

Colorectal cancer (CRC) progression is shaped by metabolic reprogramming and complex interactions within the tumor microenvironment. However, the cellular heterogeneity, spatial organization, and clinical relevance of glycolytic activity in CRC remain incompletely understood. In this study, we integrated single-cell RNA sequencing, bulk transcriptomics, and spatial transcriptomics data to systematically characterize glycolytic heterogeneity in CRC. Glycolytic activity was quantified using five independent scoring methods, consistently showing that epithelial cells exhibited the highest glycolytic activity across the two single-cell cohorts. Stratification of CopyKAT-verified aneuploid malignant epithelial cells into high-glycolysis (HG) and low-glycolysis (LG) subgroups by glycolysis scores revealed that HG cells exhibited higher stemness scores and chromosomal copy number variations. Cell-cell communication analysis revealed that, compared with LG cells, HG cells exhibited increased interaction frequency and strength with immune and stromal populations, indicating enhanced malignant epithelial-microenvironment crosstalk. Spatial transcriptomics analyses further revealed that glycolytic activity varied across normal colorectal tissue, primary CRC, and colorectal liver metastases, accompanied by progressive remodeling of epithelial-associated spatial niches and MIF-mediated intercellular communication. Bulk transcriptomic analysis identified a glycolysis-related prognostic signature with robust predictive performance, which served as an independent prognostic factor for overall survival in CRC cohorts. Collectively, these findings indicate that glycolytic heterogeneity is a key feature of CRC malignant epithelial cells and is closely associated with tumor progression, microenvironmental remodeling, and clinical outcomes.

Humans↗

Mapping antibody sequences and effector functions across spatial niches.

Antibodies are fundamental to human health but can also drive pathology. Each antibody has a molecular specificity, encoded by their clonally heritable B cell receptor (BCR). Recent advances in spatial transcriptomics coupled with repertoire sequencing have enabled capturing antibody-secreting cells (ASCs) and their clonal BCR within their tissue microenvironment. However, our understanding of antibody production niches remains limited. Furthermore, where antibodies are produced can be distinct from where antibodies exert their effector function. Here, we propose a conceptual spatial framework to distinguish between 'antibody production niches', defined by the ASC, BCR, and niche composition, versus 'antibody functional niches', composed of the antibody, antigen, and effector landscape. We then examine the possibilities and challenges to map and link antibody-encoding sequences and antibody effector functions using current and emerging technologies. Combined, we argue that integrating spatial sequence data with the antibody functional context is essential to decode the architecture of antibody-mediated immunity.

Humans↗

[Niches of dominant grub populations in different athletic areas of golf course].

The study on the temporal niche, spatial niche and spatial distribution of dominant grub populations in different athletic areas of golf courses in subtropics showed that except the lower temporal niche breadths of individual grubs in greens III and IV, the dominant grub populations in 4 areas of fairways and greens all had a >0.9 temporal niche breadth. The temporal niche breadth of 4 grub species in fairway highland and greens I and II was the highest, and that in rough highland and green IV was the lowest. For the grub species except Holotrichi-avata, the one-sided low vertical spatial niche breadth was 0.2-0.7. The temporal niche overlap in fairways and greens of 4 grub species was above 0.8, and the spatial niche overlap of great majority grub species was about 0.1-0.6. The spatial niche overlap between Anomala corpulenta and Anomala cupripes in fairways was the highest (>0.8), and that between Anomala corpulenta and Anomala cupripes and between Holotrichi asauteri and Holotrichi-avata in greens was the highest (>0.8). 4 grub species in fairways and greens mainly activated in 0-5 and 5-10 cm soil layers, a few grubs in 10-15 cm soil layer of fairway, and 4 grub species almost could not activate and feed in 10-15 cm soil layer of green.

Animals↗

[Spatial and temporal niches of Aphis gossypii and its predatory enemies].

The research results showed that Aphis gossypii had a narrow temporal niche breadth and a wide spatial niche breadth. This implied that the occurrence of A. gossypii population had the characteristics of obvious peak-period and whole-plant damage. The temporal-dynamic spatial niche breadthes of A. gossypii had no relativity to its own population densities. This implied that the damage of A. gossypii was complicated. Among the predatory enemies, Erigonidium graminicola and Propylaea japonica had wider temporal and spatial niche breadthes than other predatory enemies, and it meant that the above two enemies had longer period of occurrence and wider range of distribution. The temporal x spatial niche overlap of the predatory enemies with A. gossypii was in order of Theridium octomaculatum > P. japonica > E. graminicola > total of other enemies > Geocoris ochropterus > Misumenops tricuspidatus > Orius minutes, and the other was consistent with that of relational grades of A. gossypii and its predatory enemy populations. This result showed that the sympatry and synchronism of predatory enemies with A. gossypii had close relation to the predatory effect of the natural enemies.

Animals↗

[Characteristics, dynamics and niche of insect community in plum orchard].

The insect community in plum orchard was investigated on organization level and temporal-spatial niche. The results showed that the insect community was abundant, which included 6 orders, 23 families. The individuals of species, diversity indices, and evenness increased with time. Myzus persicae and Asiaarposina sasokii had the widest spatial niche breadth, while Didesmococcus koreauus borchs had the widest temporal niche breadth. Among the natural enemies, Chilocorus rubidus had the widest both temporal and spatial niche breadth. The niche of Chicocorus rubidus and Didesmococcus koreauus overlapped larger than that of the others, which indicated their synchrony in temporal dimension and their similarity in spatial dimension. As the dominant natural enemies, the two populations should be protected and utilized to control plum pest.

Animals↗

[Population structure and niche of main scale insects in jujube orchards intercropped with wheat].

To effectively control the scale insects in jujube orchards, a field study was made on the population structure and niche of Pseudococcus comstock Kuwane, Ceroplastes japonicus Green and Quadraspidiotus perniciosus Comstock in the jujube orchards intercropped with wheat in Taigu area of Shanxi Province. The results showed that at the early development stage of jujube trees, these three kinds of scale insects mainly distributed on the southeast direction of the lower and central parts of the tree crown, and P. comstock was the dominant species, with a wider breadth of two-dimensional temporal-spatial niche than the other two scale insects. At the mid-stage of jujube trees development, these scale insects mainly distributed on the northwest direction of the upper part of the tree crown, C. japonicus had a wider breadth of two-dimensional temporal-spatial niche than the other two scale insects, and the niche proportional similarity and interspecific competition of the three kinds of scale insects were not obvious. At the later stage of jujube trees development, there was no significant difference (P > 0.05) in the population structure of the three kinds of scale insects on the different parts and directions of tree crown, but the density of Q. perniciosus was bigger, and C. japonicus had a wider breadth of two-dimensional temporal-spatial niche. The average values of niche proportional similarity and interspecific competition of the three kinds of scale insects were smaller (P < 0.05) at the later development stage of jujube trees. Therefore, P. comstock should be controlled at the early development stage of jujube trees, all the three kinds of scale insects should be controlled selectively at the mid-stage of jujube trees development, and their overwinterings should be decreased by all means at the later development stage of jujube trees.

Agriculture↗

Resource variation and the structure of British bird communities.

Data on the foraging microhabitats of British birds are reanalyzed with the aim of understanding how fluctuations in resource abundance affect niche relationships and community structure. At Marley Wood, overlap in the foraging sites of resident bird species increased during the late spring and summer and decreased during the fall and winter. Among bird species coexisting in the pine forests at Thetford Chase, spatial overlap and spatial niche widths were positively correlated with food abundance over a 4-year period. These results suggest that in variable environments similarity in spatial niches is an inverse function of the intensity of competition for food. As food supplies drop, consumer species must apparently occupy increasingly different foraging areas in order to coexist. In less variable environments, however, resource stability may allow finer partitioning of the available foraging space and greater spatial overlap within a given foraging area. The results of this paper also suggest a reinterpretation of MacArthur's study of resource partitioning among warbler species in the boreal forests of New England. Rather than providing an instance of niche segregation in order to avoid intense competition, MacArthur's warblers may actually represent another example of increased spatial similarity when food resources are abundant and competition is reduced.

Journal Article↗

Spatially defined microenvironmental niches are associated with clinical outcome and tumor ecosystem diversity in head and neck cancer.

BACKGROUND: Head and neck squamous cell carcinoma (HNSCC) exhibits substantial biological heterogeneity that is not fully explained by human papillomavirus (HPV) status. The spatial organization of tumor, immune, and stromal cell populations and its relationship to clinical outcome remain incompletely understood. METHODS: We performed single-cell spatial transcriptomic and proteomic profiling of 44 primary HNSCC tumors, generating a spatial atlas of 19,471,501 cells across whole-slide tissue sections. Spatial niches and ecosystem states were identified through integrated computational analyses and evaluated for associations with tumor programs, clinicopathologic features, and patient outcomes. FINDINGS: HPV-negative tumors were enriched for fibroblast-rich, immune-poor niches associated with epithelial-mesenchymal transition and hypometabolic tumor programs, whereas HPV-positive tumors displayed more diverse immune, stromal, and vascular niche combinations and were enriched for immunogenic ecosystem states. Approximately 20% of HPV-positive tumors exhibited fibroblast-rich ecosystem architectures resembling HPV-negative disease and were associated with less favorable outcomes than other HPV-positive tumors of similar stage. In patient-derived co-culture models, extracellular matrix-associated fibroblasts were associated with epithelial-mesenchymal transition (EMT)-like tumor states, CD8+ T cell dysfunction, and chemotherapy resistance-associated phenotypes. CONCLUSIONS: Spatial ecosystem architecture is associated with clinically relevant heterogeneity beyond conventional HPV-based classification. Fibroblast-rich, immune-poor ecosystem states characterize a high-risk subset of HPV-positive tumors and may provide a framework for improved biological classification and risk stratification in HNSCC. FUNDING: This work was supported by the National Institutes of Health (R01CA291607 and R21CA267527-01) and the Feldstein Medical Foundation.

Humans↗

Spatial biology reveals altered macrophage states in immunosuppressed non-melanoma skin cancer.

Immunosuppressed patients with non-melanoma skin cancer experience worse clinical outcomes, yet the tumor immune microenvironment associated with systemic immunosuppression remains incompletely defined. Using integrated single-cell, spatial transcriptomic, multiplex immunofluorescence, and spatial epigenomic profiling across immunocompetent and immunosuppressed tumors, we found that overall immune-cell composition was largely preserved despite differences in immune-cell distribution, spatial organization, and T cell clonality. Immunosuppressed tumors demonstrated reduced intratumoral macrophage densities, decreased T cell clonal diversity, altered antigen-presenting cell and T cell spatial interactions, and distinct fibroblast- and macrophage-associated spatial niches. Multi-cohort validation across complementary spatial and single-cell platforms identified consistent alterations in innate-adaptive immune organization in immunosuppressed tumors. Together, these findings define spatial and functional remodeling of the tumor immune microenvironment under systemic immunosuppression and provide a framework for future therapeutic investigation in high-risk patients.

Humans↗

Neoadjuvant Immunotherapy Promotes the Formation of Mature Tertiary Lymphoid Structures in a Remodeled Pancreatic Tumor Microenvironment.

Pancreatic ductal adenocarcinoma (PDAC) is a rapidly progressing cancer that responds poorly to immunotherapies. Intratumoral tertiary lymphoid structures (TLS) have been associated with rare long-term PDAC survivors, but the role of TLS in PDAC and their spatial relationships within the context of the broader tumor microenvironment remain unknown. In this study, we report the generation of a spatial multiomic atlas of PDAC tumors and tumor-adjacent lymph nodes from patients treated with combination neoadjuvant immunotherapies. Using machine learning-enabled hematoxylin and eosin image classification models, imaging mass cytometry, and unsupervised gene expression matrix factorization methods for spatial transcriptomics, we characterized cellular states within and adjacent to TLS spanning distinct spatial niches and pathologic responses. Unsupervised learning identified TLS-specific spatial gene expression signatures that are significantly associated with improved survival in patients with PDAC. We identified spatial features of pathologic immune responses, including intratumoral TLS-associated B-cell maturation colocalizing with IgG dissemination and extracellular matrix remodeling. Our findings offer insights into the cellular and molecular landscape of TLS in PDACs during immunotherapy treatment.

Humans↗

Spatiotemporal mapping of tertiary lymphoid structure heterogeneity shapes immune niches and clinical outcomes in intrahepatic cholangiocarcinoma.

Intrahepatic cholangiocarcinoma (iCCA) is a highly lethal malignancy with limited therapeutic options. The spatial architecture and functional diversity of tertiary lymphoid structures (TLSs) in iCCA remain unclear. Here, we present a multimodal spatial atlas of TLSs and identified intratumoral TLSs (iTLSs) as independent prognostic markers. Bulk proteomic profiling of 214 discovery and 155 validation cases identified a four-tier TLS-based tumor microenvironment classification system and supported development of a TLS-predictive random forest classifier. Imaging mass cytometry revealed that iTLS+ tumors harbor structured immune architectures, where M1-like tissue-resident macrophages (RTMs), dendritic cells, and CXCL13+ CD4+ T cells colocalize to form antigen-presenting neighborhoods (apc-CNs) spatially coupled to TLS core regions (TLScore-CNs). Single-cell spatial transcriptomics further resolved 61 TLSs into 14 spatial niches and defined a pseudotemporal maturation continuum: aggregated, activated, and postactivated. Intraniche communication, primarily mediated by ifnCAFs, iCAFs, and CXCL12+ macrophages, evolved dynamically with maturation. Single-nucleus RNA sequencing combined with Tangram-based spatial mapping revealed CXCL12+ macrophages and iCAFs forming a peripheral band in aggregated TLSs, whereas ifnCAFs infiltrated TLS interiors during activation. These findings define TLS heterogeneity and provide insights for stroma-directed immunotherapy.

Cholangiocarcinoma↗

Disturbance and diversity in experimental microcosms.

External agents of mortality (disturbances) occur over a wide range of scales of space and time, and are believed to have large effects on species diversity. The "intermediate disturbance hypothesis", which proposes maximum diversity at intermediate frequencies of disturbance, has received support from both field and laboratory studies. Coexistence of species at intermediate frequencies of disturbance is thought to require trade-offs between competitive ability and disturbance tolerance, and a metapopulation structure, with disturbance affecting only a few patches at any given time. However, a unimodal relationship can also be generated by global disturbances that affect all patches simultaneously, provided that the environment contains spatial niches to which different species are adapted. Here we report the results of tests of this model using both isogenic and diverse populations of the bacterium Pseudomonas fluorescens. In both cases, a unimodal relationship between diversity and disturbance frequency was generated in heterogeneous, but not in homogeneous, environments. The cause of this relationship is competition among niche-specialist genotypes, which maintains diversity at intermediate disturbance, but not at high or low disturbance. Our results show that disturbance can modulate the effect of spatial heterogeneity on biological diversity in natural environments.

Ecosystem↗

ARCADIA reveals spatially dependent transcriptional programs through integration of scRNA-seq and spatial proteomics.

MOTIVATION: Cellular states are strongly influenced by spatial context, but single-cell RNA sequencing (scRNA-seq) loses information about local tissue organization, while spatial proteomic assays capture limited marker panels that constrain transcriptomic inference. Integrating these modalities can elucidate how spatial niches shape transcriptional programs, yet existing approaches depend on either feature-level correspondence such as gene-protein linkage or cell-level barcode pairing, which is often unavailable. RESULTS: We present ARCADIA (ARchetype-based Clustering and Alignment with Dual Integrative Autoencoders), a generative framework for cross-modal integration that operates without cell barcode pairing and does not assume direct feature-to-feature correspondence. ARCADIA identifies modality-specific archetypes, that is, convex combinations of cells representing extreme phenotypic states, and aligns these anchors across modalities by minimizing the discrepancy between their cell-type composition profiles. The aligned archetypes define a shared coordinate system that anchors dual variational autoencoders (VAEs) trained with cross-modal geometric regularization, preserving archetype structure and spatial neighborhood information while enabling bidirectional translation between modalities. On semi-synthetic CITE-seq data, ARCADIA outperforms existing weak-linkage methods. Applied to independent human tonsil scRNA-seq and CODEX data, ARCADIA reconstructs known tissue architecture and reveals spatially dependent transcriptional programs linking B-cell maturation and T-cell activation or exhaustion to microenvironmental niches. AVAILABILITY AND IMPLEMENTATION: Source code is accessible at https://github.com/azizilab/ARCADIA_public. Reproducibility scripts and data are available at https://github.com/azizilab/arcadia_reproducibility.

Proteomics↗

Beyond Morphology: Reframing Lymph-Node Metastasis Prediction Through Clonal Ecology-Decades-Long Genomic Instability and Polyclonal-to-Monoclonal Transitions as the Missing Dimension in Cancer.

Recent whole-genome, lineage-tracing, single-cell, and spatial studies have reshaped our understanding of tumor evolution, revealing that cancers can arise from polyclonal populations, undergo decades-long genomic instability before clinical detection, and progress through dynamic changes in subclonal composition, cellular state, and ecological organization. These findings challenge the assumption underlying morphology-based prediction models that metastatic risk can be inferred from static histological features alone. Here, we revisit lymph-node metastasis prediction in colorectal cancer through clonal ecology, integrating computational pathology with evolutionary oncology. Drawing on the subclonal switchboard model proposed in 2012 and subsequent artificial intelligence (AI)-enabled approaches for tracking dominant and dormant subclones, we synthesize evidence that metastatic potential reflects clonal ancestry, evolutionary timing, spatial niche architecture, cellular plasticity, intercellular interactions, dormancy, and treatment-driven shifts in subclonal fitness. We define five complementary methodological pillars for operationalizing clonal ecology: single-cell transcriptomics for resolving rare subclones, evolutionary trajectories, and adaptive cell states; lineage tracing and phylogenetics for reconstructing clonal ancestry and divergence; spatial transcriptomics and genomics for mapping subclonal geography and tumor-stromal-immune interactions; longitudinal liquid biopsy surveillance for monitoring residual disease, clonal turnover, and emerging resistance; and AI-enabled multimodal integration for connecting histopathology, genomics, spatial biology, and longitudinal data into predictive ecological-state models. Multiple-instance learning and pathology foundation models provide scalable computational foundations for evolution-aware prediction. Translationally, dormant subclones represent actionable reservoirs of recurrence. A longitudinal clinical and experimental study of KMT2A-rearranged acute myeloid leukemia further supports central predictions of the subclonal switchboard framework by demonstrating treatment-associated shifts in subclonal dominance, persistence of cryptic adaptive programs, and ecological rewiring during resistance and relapse. We propose clonal ecology as a measurable dimension for extending morphology-driven prediction toward integrative models that anticipate evolutionary transitions, identify therapeutic windows, and proactively constrain adaptive tumor ecosystems before resistant or metastatic subclones achieve clinical dominance.

Humans↗

Ecological consequences of island colonization by southwest pacific birds, I. Types of niche shifts.

The land and fresh-water birds of the southwest Pacific islands derive mainly from New Guinea and offer a favorable situation for studying ecological consequences of island invasions. The reduction of competition on species-poor islands permits some colonizing species to expand their niches spatially, by occupying altitudinal bands, types of habitats, and/or vertical strata of the forest from which they are excluded by other species on species-rich islands. Expansions to higher altitudes, or from second-growth into forest, are especially frequent. Other colonists become more abundant in the same type of habitat preferred on New Guinea. Instances of a change in diet are rare. Changes in foraging technique are noted mainly for those colonists that have been isolated long enough to have undergone morphological divergence. Approximately half of the colonizing populations experience no niche shift.

Journal Article↗

Vertical distribution of an ectomycorrhizal community in upper soil horizons of a young Norway spruce (Picea abies [L.] Karst.) stand of the Bavarian Limestone Alps.

The vertical niche differentiation of genera of ectomycorrhiza (ECM) was assessed in a 17-year-old Norway spruce (Picea abies [L.] Karst.) plantation on a mountainous dolomitic site (1,050 m above sea level) of the Bavarian Limestone Alps. We determined ECM anatomotypes, recorded the abundance of corresponding ECM root tips and classified them into groups of ECM exploration types, which refer to the organisation and the extent of their extramatrical mycelia. The abundance of ECM was highest in the organic soil layers, compared to the mineral soil horizon. The ordination of the ECM communities and of the exploration types revealed segregation related to soil horizon properties. While Cenococcum geophilum preferred the organic soil layers, Lactarius spp., Tomentella spp. and Craterellus tubaeformis were generally most abundant in the mineral soil horizons. Cenococcum geophilum was the predominant species, possibly based on enhanced competitiveness under the prevailing site conditions. The short-distance exploration types (e.g. C. geophilum) preferentially colonised the organic soil layer, whereas the contact types (e.g. most of the Tomentella spp., C. tubaeformis) together with medium-distance types (e.g. Amphinema byssoides) were primarily associated with the underlying A-horizons. Therefore, the soil horizons had an important effect on the distribution of ECM and on their community structure. The spatial niche differentiation of ECM genera and exploration types is discussed in regard to specific physico-chemical properties of soil horizon and the assumed ecophysiological strategies of ECM.

Biodiversity↗