PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Transcriptomic alterations”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 253 records · Page 14Linked to original sources

Systematic characterization of neurotransmitter receptor dysregulation identifies a neural-related prognostic signature associated with biochemical recurrence in prostate cancer.

BACKGROUND: The nervous system is increasingly recognized to play a critical role in tumor initiation and progression. Central to this complex relationship are the interactions between neurotransmitters secreted by neurons and their receptors (neurotransmitter receptors, NTRs) expressed on cancer cells, which activate multiple intracellular signaling pathways. However, the spectrum of NTR dysregulation and its association with biochemical recurrence (BCR) in prostate cancer (PCa) has not been explored. Therefore, the aim of this study was to fill this gap. METHODS: We systematically characterized the expression profiles of 130 NTR genes by integrating bulk and single-cell transcriptomic data. Consistently dysregulated NTR (cdNTR) genes were identified and used to construct a PCa signature (PCaSig) using elastic-net regression. The robustness of PCaSig was evaluated across three independent cohorts. In addition, the associations of PCaSig with clinicopathological characteristics, genomic alterations, tumor immune-related characteristics, and biological pathways were comprehensively investigated. RESULTS: Thirteen cdNTR genes with strong cell-type specificity, particularly in luminal epithelial cells, were identified. PCaSig robustly stratified patients into distinct BCR risk groups across multiple independent cohorts and remained an independent predictor after adjustment for clinicopathological factors. High PCaSig scores were associated with aggressive clinicopathological features, elevated tumor mutation burden (TMB), suppression of neurotransmitter-related signaling, and activation of cell-cycle and immune-related pathways. Notably, PCaSig refined prognostic stratification regardless of TMB status and was associated with distinct immune-related characteristics, including immune checkpoint expression and immune cell infiltration. Incorporation of PCaSig into a clinical nomogram significantly improved prognostic accuracy and clinical net benefit. CONCLUSIONS: These findings establish NTR dysregulation as a previously underappreciated dimension of PCa and support PCaSig as a clinically relevant tool for personalized management.

Neurotransmitter receptor (NTR)↗

Transcriptional benchmark dose modeling of ultraviolet radiation-induced genomic activation in mouse skin.

The in vivo transcriptional response of mouse skin to ultraviolet radiation (UV-R) exposure reveals key genomic alterations associated with UV-R-induced damage but it does not provide precise dose thresholds for these effects. These initial findings provided the impetus to advance dose-response characterization by integrating benchmark dose (BMD) modeling with transcriptomic data, aiming to identify biologically relevant points of departure for gene and pathway activation. To accomplish this, mice were exposed to five erythemally weighted UV-R doses (0-40 mJ/cm2) emitted from a UV-emitting tanning device, across six post-exposure timepoints (0-96 h). Four analytical methods were used to estimate BMDs, with the lowest consistent response dose (LCRD) approach yielding the most sensitive estimates (1.21-3.44 mJ/cm2). Transcriptomic responses revealed activation of shared pathways related to DNA damage and cancer, oxidative stress and metabolism, inflammation and immunity, and hormonal disruption. Notably, the majority of LCRD BMD estimates (1.21-3.44 mJ/cm2) were lower than the International Electrotechnical Commission standard actinic exposure limit (3 mJ/cm2 (erythemally weighted)) for broadband UV-R (200-400 nm) for unprotected skin and the eye for an 8 h period. These findings suggest that transcriptomic BMD modeling can detect early biological responses to UV-R at doses lower than current exposure limits.

Animals↗

Systems Analysis Reveals Contraceptive-Induced Alteration of Cervicovaginal Gene Expression in a Randomized Trial.

Hormonal contraceptives (HCs) are vital in managing the reproductive health of women. However, HC usage has been linked to perturbations in cervicovaginal immunity and increased risk of sexually transmitted infections. Here, we evaluated the impact of three HCs on the cervicovaginal environment using high-throughput transcriptomics. From 2015 to 2017, 130 adolescent females aged 15-19 years were enrolled into a substudy of UChoose, a single-site, open-label randomized, crossover trial (NCT02404038) and randomized to injectable norethisterone-enanthate (Net-En), combined oral contraceptives (COC), or etonorgesterol/ethinyl-estradiol-combined contraceptive vaginal ring (CCVR). Cervicovaginal samples were collected after 16 weeks of randomized HC use and analyzed by RNA-Seq, 16S rRNA gene sequencing, and Luminex analysis. Participants in the CCVR arm had a significant elevation of transcriptional networks driven by IL-6, IL-1, and NFKB, and lower expression of genes supporting epithelial barrier integrity. An integrated multivariate analysis demonstrated that networks of microbial dysbiosis and inflammation best discriminated the CCVR arm from the other contraceptive groups, while genes involved in epithelial cell differentiation were predictive of the Net-En and COC arms. Collectively, these data from a randomized trial represent the most comprehensive "omics" analyses of the cervicovaginal response to HCs and provide important mechanistic guidelines for the provision of HCs in sub-Saharan Africa.

HIV↗

Genetic and molecular evidence linking CTSH to Alzheimer's disease pathophysiology.

INTRODUCTION: Lysosomal dysfunction contributes to Alzheimer's disease (AD) by impairing protein clearance and promoting neuroinflammation. Cathepsin H (CTSH), a lysosomal protease, recently emerged as a protective AD locus. We investigated how CTSH is regulated and how it influences early AD pathophysiology. METHODS: We analyzed genomic, transcriptomic, and proteomic data from cerebrospinal fluid (CSF) and brain tissue across three independent clinical and post mortem cohorts to assess CTSH regulation, expression, and disease associations. RESULTS: The coding variant rs2289702 acts as a cis-regulatory variant, altering CTSH mRNA and protein levels. The T allele associates with better cognition and reduced amyloid plaque burden. CSF CTSH correlates with total tau, phosphorylated tau181, neuronal markers, and multiple glial and complement-related inflammatory proteins. DISCUSSION: CTSH tracks early neurodegenerative, synaptic, and inflammatory changes, and co-expression analyses link it to broader immune-metabolic pathways. The findings position CTSH as a genetically regulated contributor to AD pathophysiology.

Humans↗

Characterization of the genomic and transcriptomic landscape of invasive non-mucinous lung adenocarcinoma based on IASLC grading.

BACKGROUND: The IASLC grading system has prognostic utility and potential therapeutic implications in invasive non-mucinous lung adenocarcinoma (LUAD), but the molecular basis underlying the grading spectrum remains unclear. METHODS: We performed whole-genome sequencing in 138 Chinese patients with invasive non-mucinous LUAD and RNA sequencing of 96 matched tumor-normal tissue pairs to systematically characterize the molecular features across grades, including coding driver events, mutational signatures, non-coding regulatory disruptions, and transcriptional programs. RESULTS: Compared with Grade 1-2 tumors, Grade 3 LUADs exhibited heightened invasive potential, manifested by more advanced stage, more frequent spread through air spaces, and independently worse survival. Grade 3 tumors had elevated tumor mutational burden and were enriched for alterations in genome maintenance and cell-cycle genes, including TP53, as well as genes implicated in DNA damage response, including ZFHX4. APOBEC-associated mutagenesis was selectively enriched in Grade 3 tumors independent of smoking status, consistent with an instability-associated phenotype. Recurrent non-coding regulatory disruptions affected lung lineage-defining genes, particularly surfactant-associated genes, and were correlated with reduced expression. Transcriptomic profiling revealed epithelial dedifferentiation, loss of pulmonary homeostatic programs, and activation of proliferative and stress-related pathways. Notably, MUC16 emerged as a convergent event linking genomic and transcriptional dysregulation, with coding mutations associated with higher expression and increased expression in Grade 3 tumors correlating with the proportion of high-grade histologic patterns. CONCLUSIONS: These findings provide a molecular framework for the IASLC grading spectrum and identify Grade 3 LUAD as a distinct instability-associated and dedifferentiated biological state.

IASLC grading↗

Influenza A Virus Coinfection Alters Streptococcus pneumoniae Gene Expression during Upper Respiratory Tract Colonization.

Streptococcus pneumoniae (Spn) asymptomatically colonizes the upper respiratory tract (URT), a niche from which it can transmit to another host or cause invasive disease in the same host. The in vivo transcriptional adaptations that Spn undergoes during nasopharyngeal colonization, particularly during influenza A virus (IAV) coinfection, are poorly understood. Here, we leveraged an established infant mouse model of colonization, shedding, and transmission to perform genome-wide transcriptomic profiling of Spn during mono- and during IAV co-infection. Compared with broth-grown controls, pneumococci isolated from the URT exhibited distinct transcriptional programs, with over 200 genes differentially expressed across time points. Genes involved in carbohydrate uptake and metabolism, glycan degradation, amino sugar and nucleotide sugar metabolism, and amino acid biosynthesis were consistently enriched during colonization, highlighting metabolic adaptation to the nasopharyngeal niche. In contrast, IAV coinfection induced a markedly distinct transcriptional signature, including upregulation of branched-chain amino acid biosynthesis, bacteriocin production, and phosphate acquisition systems. Notably, the pilus islet-1 locus was upregulated during Spn-IAV coinfection. Functional studies demonstrated that while the pilus was dispensable for colonization under mono- and coinfection conditions, it promoted high-shedding events and enhanced inflammatory responses during IAV coinfection. However, reduced inflammation and reduced high shedding events from pups inoculated with a pilus-deficient mutant did not alter transmission frequency in the infant mouse model. Collectively, our findings define the in vivo transcriptional landscape of Spn during URT colonization and reveal distinct bacterial adaptations during viral coinfection, providing insight into mechanisms that influence pneumococcal persistence, inflammation, and transmission.

Journal Article↗

PSIP1::TBL1X: a recurrent gene fusion in pancreatic neuroendocrine tumors.

Effective treatment of metastatic neuroendocrine tumors (NETs) is limited by a lack of targeted therapies and clinically useful predictive biomarkers. We applied complementary genomic profiling technologies, including optical genome mapping (OGM) and whole exome sequencing (WES), to 70 liver metastases of NETs from multiple anatomical primary sites to identify actionable genomic alterations. We detected recurrent fusions involving TBL1X (PSIP1::TBL1X) and BEND2 (CHD7::BEND2 and NEO1::BEND2) by OGM in pancreatic neuroendocrine tumors (pNETs). The expression of the PSIP1::TBL1X fusion was confirmed by PacBio Iso-Seq long-read transcriptome sequencing and nested rtPCR, and fusion protein expression was established by western blotting. Expression of the PSIP1::TBL1X fusion was also assayed in a separate cohort of 31 specimens from 28 pNET cases by rtPCR. Across both cohorts, PSIP1::TBL1X was identified in 11% of pNET patients with available metastatic tissue, but was not detected in primary tumor specimens. All PSIP1::TBL1X fusion isoforms were found to retain early exons of PSIP1 and the complete coding sequence of TBL1X. Consistent with prior reports, BEND2 fusions were associated with high-grade tumors and may represent a clinically useful biomarker for aggressive disease. Notably, TBL1X and BEND2 fusions did not co-occur with ATRX/DAXX mutations, defining a distinct molecular subgroup of pNETs. This study highlights the importance of structural variant profiling in molecular profiling studies and supports a revised view of the role of gene fusions in neuroendocrine malignancies.

Humans↗

Integrated Genomic and Epigenomic Analysis Reveals Epigenetic Plasticity in Disease Progression and Multidrug Resistance in Multiple Myeloma.

UNLABELLED: Multiple myeloma is marked by recurrent cytogenetic abnormalities and mutations that accumulate as the disease progresses. In this study, we sought to elucidate the transitions driving tumorigenesis and therapy resistance in multiple myeloma using a unique cohort of nearly 900 patients spanning premalignant to late-stage refractory multiple myeloma, comprehensively characterized at molecular and clinical levels. Waves of epigenetic dysregulation drove these critical transitions. In this paradigm, genomic and cytogenetic events unlocked epigenetic plasticity, reshaping multiple myeloma cell biology to evade tumor microenvironment constraints and therapeutic pressures. Functional perturbation studies in an isogenic proteasome inhibitor-resistant cell line model demonstrated enhanced reliance on transcriptional cofactors, supporting a mechanistic link between chromatin plasticity and therapy adaptation. Collectively, these findings support a unifying framework in which genomic heterogeneity unlocks gene regulatory plasticity, enabling plasma cells (PC) to evade microenvironmental constraints and therapeutic pressure. These results provide a mechanistic explanation for sequential relapse without new genomic alterations and nominate epigenetic plasticity-mediated PC adaptation as a therapeutic vulnerability in the heterogeneous genetic background of multiple myeloma. SIGNIFICANCE: Assembly and analysis of a multiple myeloma cohort spanning the continuum from premalignant to late relapse that integrates bulk transcriptomics with single-cell multiomic data provides insights into disease progression and epigenetic plasticity.

Multiple Myeloma↗

Influenza A virus co-infection alters Streptococcus pneumoniae gene expression during upper respiratory tract colonization.

Streptococcus pneumoniae (Spn) asymptomatically colonizes the upper respiratory tract (URT), a niche from which it can transmit to another host or cause invasive disease in the same host. The in vivo transcriptional adaptations that Spn undergoes during nasopharyngeal colonization, particularly during influenza A virus (IAV) co-infection, are poorly understood. Here, we leveraged an established infant mouse model of colonization, shedding, and transmission to perform genome-wide transcriptomic profiling of Spn during mono- and during IAV co-infection. Compared with broth-grown controls, pneumococci isolated from the URT exhibited distinct transcriptional programs, with over 200 genes differentially expressed across time points. Genes involved in carbohydrate uptake and metabolism, glycan degradation, amino sugar and nucleotide sugar metabolism, and amino acid biosynthesis were consistently enriched during colonization, highlighting metabolic adaptation to the nasopharyngeal niche. In contrast, IAV co-infection induced a markedly distinct transcriptional signature, including upregulation of branched-chain amino acid biosynthesis, bacteriocin production, and phosphate acquisition systems. Notably, the pilus islet-1 locus was upregulated during Spn-IAV co-infection. Functional studies demonstrated that while the pilus was dispensable for colonization under mono- and co-infection conditions, it promoted high-shedding events and enhanced inflammatory responses during IAV co-infection. However, reduced inflammation and reduced high-shedding events from pups inoculated with a pilus-deficient mutant did not alter transmission frequency in the infant mouse model. Collectively, our findings define the in vivo transcriptional landscape of Spn during URT colonization and reveal distinct bacterial adaptations during viral co-infection, providing insight into mechanisms that influence pneumococcal persistence, inflammation, and transmission.

RNA-seq↗

Application of a Translational Research Platform to Unveil Efficacy Signals and Mechanisms of Resistance of FGFR Inhibitors in Multiple FGFR-Altered Solid Tumors.

PURPOSE: The predictive value of fibroblast growth factor receptor (FGFR) amplifications (amp) and the role of FGFR mutations (mut) beyond known activating variants remain unclear. We aimed to establish a translational research platform to characterize FGFR alterations (alt) and explore their potential as predictive biomarkers for FGFR-targeted agents. EXPERIMENTAL DESIGN: This ambispective study included a retrospective analysis of patients with FGFR-alt tumors treated with selective FGFR inhibitors (FGFRi) and a prospective collection of longitudinal tumor samples. Patient-derived xenografts (PDX) were generated to investigate FGFRi mechanisms of action and resistance. Molecular characterization included genomic, transcriptomic, proteomic, and functional analyses using the Functional Annotation for Cancer Treatment (FACT) assay. RESULTS: Among 36 retrospectively analyzed patients, clinical benefit from FGFRis was observed in cases with FGFR mRNA overexpression or FGFR2/11q co-amp, but no association was found with the amplification levels. In archival tumor samples, exploratory proteomic analysis showed FGFR1-4 protein expression in 78% of FGFR1/2-amp tumors detected by fluorescence in situ hybridization. RNA sequencing identified a higher prevalence of FGFR mRNA overexpression than proteomic analysis. Among patients harboring FGFR-mut, only one bladder cancer with an FGFR3-mut S249C derived benefit. FACT assay supported the functional activity of selected variants, including FGFR3 T689M, and suggested potential resistance mechanisms involving PI3K/PTEN and MAPK pathway co-alterations. A prospective FGFR-alt PDX biorepository enabled exploratory biomarker analyses, supporting the hypothesis that FGFR1-4 mRNA expression may better reflect FGFR dependency than genomic alterations alone. CONCLUSIONS: These findings highlight the complexity of FGFR-driven oncogenesis and support integrative molecular approaches to refine patient selection for FGFR-targeted therapies.

Humans↗

Loss of Function Dnmt3a Mutation Leads to Aberrant Neutrophil Migration.

Clonal hematopoiesis (CH), an age-related expansion of somatically mutated hematopoietic clones, is associated with increased risk of severe infections including coronavirus disease (COVID)-19, yet the underlying mechanisms remain unclear. Here, we investigated the impact of Dnmt3a deficiency in a murine model of influenza A virus (IAV) pneumonia. Dnmt3a-deficient mice exhibited increased pulmonary viral burden and reduced neutrophil accumulation in IAV-infected lungs despite comparable circulating neutrophil numbers. Functional analyses of neutrophils showed impaired chemotactic migration in vitro, whereas maturation, antimicrobial enzyme content, and metabolic capacity were unchanged. Transcriptomic profiling revealed downregulation of pathways involved in chemotaxis, cytokine signaling, and cellular activation, including reduced expression of Cxcr1. Supporting the translational relevance of these findings, proteomic analysis of plasma from individuals with germline DNMT3A mutations (Tatton-Brown-Rahman syndrome) revealed alterations in proteins associated with cell migration and cytoskeletal dynamics. Collectively, our findings demonstrate that Dnmt3a loss compromises innate immune defense by impairing neutrophil migration in a cell-intrinsic manner, leading to ineffective pathogen clearance. This work provides mechanistic insight into how CH-associated mutations contribute to age-associated susceptibility to infection and highlights altered leukocyte trafficking as a potential therapeutic target in aging populations with CH.

Animals↗

Single-cell transcriptional profiling identifies the swimming crab Portunus trituberculatus in response to bacterial infection.

Crustaceans rely entirely on innate immunity, yet the cellular composition, functional specialization, and pathogen-induced remodeling of their immune system remain poorly resolved. Here, we generated a high-resolution single-cell transcriptomic atlas of hemocytes from the swimming crab Portunus trituberculatus following Vibrio parahaemolyticus infection using 10× Genomics scRNA-seq. Seven putatively distinct hemocyte clusters were identified, including granulocytes, semigranular hemocytes, prohemocytes, unresolved hemocytes, hyalinocyte-like hemocytes, biosynthetically active secretory hemocytes, and regulatory hemocytes. Although the overall cellular composition remained relatively stable after infection, hemocytes exhibited pronounced cluster-specific transcriptional reprogramming involving Toll/NF-κB signaling, antimicrobial peptide synthesis and metabolic rewiring. By integrating single-cell and bulk transcriptomes, we identified multiple anti-lipopolysaccharide factors (ALFs) as key secretory effectors and experimentally validated their antibacterial activities. FITC-based bacterial engulfment assays and RNA-seq of sorted phagocytes demonstrated that phagocytic capability was shared across multiple hemocyte clusters. Notably, the immunoglobulin superfamily receptor DSCAM displayed extensive alternative splicing and strong infection-induced activation in unresolved hemocytes. Immune-training experiments showed that prior bacterial exposure was associated with altered DSCAM expression and reduced early cumulative mortality upon secondary challenge, suggesting a memory-like immune phenotype. These findings provide a foundational framework for understanding crustacean immunity and advancing disease-resistant breeding in aquaculture.

Antimicrobial peptides↗

Pterostilbene Targets Hallmarks of Aging in the Gene Expression Landscape in Blood of Healthy Rats.

SCOPE: Polyphenols from the phytoestrogen group, including pterostilbene (PTS), are known for their antioxidant, anti-inflammatory, and anti-cancer effects. In recent reports, phytoestrogens attenuate age-related diseases; however, their pro-longevity effects in healthy models in mammals remain unknown. As longevity research demonstrates age-related transcriptomic signatures in human blood, the current study hypothesizes that phytoestrogen-supplemented diet may induce changes in gene expression that ultimately confer pro-longevity benefits. METHODS AND RESULTS: In the present study, RNA sequencing is conducted to determine transcriptome-wide changes in gene expression in whole blood of healthy rats consuming diets supplemented with phytoestrogens. Ortholog cell deconvolution is applied to analyze the omics data. The study discovered that PTS leads to changes in the gene expression landscape and PTS-target genes are associated with functions counteracting hallmarks of aging, including genomic instability, epigenetic alterations, compromised autophagy, mitochondrial dysfunction, deregulated nutrient sensing, altered intercellular interaction, and loss of proteostasis. These functions bridge together under anti-inflammatory effects through multiple pathways, including immunometabolism, where changes in cellular metabolism (e.g., ribosome biogenesis) impact the immune system. CONCLUSION: The findings provide a rationale for pre-clinical and clinical longevity studies and encourage investigations on PTS in maintaining cellular homeostasis, decelerating the process of aging, and improving conditions with chronic inflammation.

Animals↗

An Annotated Biobank of Triple-Negative Breast Cancer Patient-Derived Xenografts Features Treatment-Naïve and Longitudinal Samples during Neoadjuvant Chemotherapy.

UNLABELLED: Triple-negative breast cancer (TNBC) that fails to respond to neoadjuvant chemotherapy (NACT) can be lethal. Developing effective strategies to eradicate chemoresistant disease requires experimental models that recapitulate the heterogeneity characteristic of TNBC. To that end, we established a biobank of 92 orthotopic patient-derived xenograft (PDX) models of TNBC from the tumors of 75 patients enrolled in A Robust TNBC Evaluation fraMework to Improve Survival clinical trial (ARTEMIS, NCT02276443), including 12 longitudinal sets generated from serial patient biopsies collected throughout NACT treatment and from metastatic disease. Models were established from both chemosensitive and chemoresistant tumors, and nearly 30% of the PDX models were capable of metastasizing to the lungs. Comprehensive molecular profiling demonstrated conservation of genomes and transcriptomes between patient and corresponding PDX tumors, with representation of all major transcriptional subtypes. Transcriptional changes observed in the longitudinal PDX models highlighted dysregulation in pathways associated with DNA integrity, extracellular matrix interactions, the ubiquitin-proteasome system, epigenetics, and inflammatory signaling. These alterations revealed a complex network of adaptations associated with chemoresistance. Overall, this PDX biobank provides a valuable tool for tackling the most pressing issues facing the clinical management of TNBC. SIGNIFICANCE: The development of a patient-derived xenograft biobank that comprehensively captures the genomic and transcriptional diversity of triple-negative breast cancer promises to be a robust resource to investigate and overcome chemoresistance and metastasis.

Animals↗

PUS7-dependent Ψ reshapes specific synaptic gene exons to facilitate fear extinction memory formation.

RNA modifications serve as dynamic regulators of neural plasticity through their ability to fine-tune transcript stability and splicing. Pseudouridine (Ψ), an evolutionarily conserved RNA modification catalyzed by pseudouridine synthases, plays established roles in neurodevelopment, yet its functional significance in activity-dependent behavioral adaptation remains poorly defined. Here, we investigate Ψ-mediated epitranscriptomic regulation within the infralimbic prefrontal cortex (ILPFC), a brain region requiring precise synaptic remodeling for the clinically relevant form of fear extinction memory. Combining transcriptome-wide pseudouridylation profiling with behavioral analysis in mice, we identified selective Ψ enrichment at exons of synaptic regulatory genes within ILPFC during fear extinction learning. Fear extinction in the ILPFC drives concomitant exonic Ψ deposition and upregulation of synaptogenic transcripts, processes that involve pseudouridine synthase PUS7. Crucially, PUS7 knockdown in the ILPFC selectively impaired fear extinction memory formation without altering baseline fear expression, establishing a causal link between Ψ-dependent RNA processing and activity-dependent synaptic structural remodeling in this microcircuit. Our findings demonstrate that PUS7-mediated Ψ modification spatiotemporally regulates activity-dependent RNA dynamics in the ILPFC, providing the evidence that epitranscriptomic mechanisms precisely coordinate synaptic gene expression within behaviorally defined brain sub-region. This work bridges molecular RNA biology with systems neuroscience, revealing a novel mechanism for activity-dependent regulation of fear extinction in ILPFC.

Animals↗

Genome assembly of Astatotilapia latifasciata uncovers B chromosome-linked chromatin reorganization.

B chromosomes (Bs) are supernumerary genomic elements found in many eukaryotes, yet their full sequence composition, functional potential, and regulatory impact on the host genome remain unclear. Here, we present a chromosome-level genome assembly of the cichlid fish Astatotilapia latifasciata, integrating PacBio long reads, Illumina short reads, and Hi-C chromatin contact maps to resolve both A and B chromosomes. The 0.93 Gb assembly (N50 = 36.2 Mb) includes a 34 Mb B chromosome containing 789 predicted protein-coding genes and a markedly higher density of transposable elements (TEs), especially long terminal repeats (LTR) retrotransposons. Transcriptome profiling revealed that B-linked genes are predominantly transcriptionally repressed relative to their A chromosome paralogs. Hi-C-based chromatin modeling uncovered distinct 3D structural configurations associated with the B chromosome, including fewer topologically associating domains (TADs), reduced loop formation, and altered compartmentalization. These changes are linked to long-range chromatin interactions and genomic rearrangements, suggesting that the B chromosome reshapes the nuclear architecture of the host genome. Our study proposes a potential regulatory role of Bs in genome and provides a genomic resource for investigating chromosome evolution in cichlids.

Animals↗

The mouse gut microbiota responds to predator odor and predicts host behavior.

Chronic stressors can alter the mammalian gut microbiota in ways that mediate host stress responses, but the impacts of acute stressors on these interactions are less well understood. Here, we show that brief exposure of wild-derived mice to predator odor altered gut-microbiota composition, which in turn predicted host behavior. We investigated the individual and combined effects of 15-minute exposures to synthetic fox fecal odor and 30 days of chronic social isolation, an established chronic stressor. Using ethological assays, visceral adipose tissue transcriptomics, and genome-resolved metagenomics, we found that predator-odor exposure significantly affected mouse behavior, gene expression, and gut microbiota. Predator odor-responsive bacteria were associated with the expression of genes involved in anti-microbial defense, and host behavioral responses were predicted by random forest models trained on gut-microbiota profiles. These findings indicate interactions between the gut microbiota and wild-mouse responses to the threat of predation, an ecologically relevant acute stressor.

Journal Article↗

The machine-learning classifier ALLCatchR2 identifies 20 T-ALL subtypes across cohorts and age groups.

T-cell acute lymphoblastic leukemia (T-ALL) comprises molecularly diverse subtypes, but robust cross-cohort validations and operational gene-expression definitions are lacking. To establish a gene-expression-anchored framework for T-ALL subtyping, we aggregated 2314 transcriptomes (15 cohorts, age: 0.8-90.8 years). An extended unsupervised approach defined 17 main clusters and 3 subclusters in samples with high blast fractions. Supervised analyses added an overarching immature T-ALL (early T cell precursor [ETP]-like) definition and resolved the LMO2 &#x3b3;&#x3b4;-like subtype. All clusters contained samples from at least two cohorts. Characteristic genomic driver enrichments were consistent across cohorts, while gene-expression clusters did not correspond exclusively to single driver events but also reflected developmental origins. A machine-learning classifier based on ALLCatchR, our B-cell acute lymphoblastic leukemia (B-ALL) classifier, identified these 20 transcriptomic subtypes and the immature T-ALL (ETP-like) signature with 0.995-1.0 accuracy in a validation set (n&#x2009;=&#x2009;203). Testing the classifier on a second hold-out data set (n&#x2009;=&#x2009;265 samples) showed that 92.7% of predictions matched with corresponding driver alterations. Across all samples, 83.2% of cases received high-confidence predictions, 7.3% candidate predictions, and 9.5% remained unclassified, largely because of low blast fractions. We identified a novel gene-expression cluster markedly enriched (P&#x2009;<&#x2009;0.001) for clonal hematopoiesis mutations (IDH2 R140Q, DNMT3A) and a stem-/progenitor cell-like gene expression. This novel clonal hematopoiesis-related T-ALL subtype was observed in six cohorts and accounted for 8.9% of adults and 39.5% of patients aged >50 years. We extended&#xa0;ALLCatchR into ALLCatchR2, a free R package that now enables B-/T-lineage separation, gene-expression subtyping, blast estimation, and developmental annotation to harmonize T-ALL classification across studies and clinical contexts.

Journal Article↗