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Comparative genomics and adult-female transcriptomics prioritize physiological candidate pathways in the aquatic acentropine moth Paracymoriza distinctalis.

Freshwater-associated life histories are rare in Lepidoptera, and the physiological systems accompanying them remain poorly resolved. We integrated adult-female whole-body RNA-seq from Paracymoriza distinctalis (n = 3) and three terrestrial crambids (n = 3, 3, and 2) with focused comparative genomics to prioritize testable candidate pathways. Adult-female expression-biased genes were enriched for muscle contraction and myofibril assembly, carbohydrate and nucleotide-related metabolism, response to stimulus, and regulation of signal transduction. Protein-interaction analysis further identified coherent modules associated with RNA processing, carbon metabolism, the citrate cycle, and RAF/MAPK signaling. At the genome level, P. distinctalis retained broad macrosynteny with two crambid relatives, whereas putative lineage-biased genes were enriched for vitelline membrane formation, embryonic development, apoptosis, cytoskeletal organization, and transferase activity. Because the transcriptomes were obtained from whole adult females, these patterns may reflect locomotor, reproductive, metabolic, and tissue-composition differences and should not be interpreted as direct mechanisms of larval aquatic adaptation. Together, the results identify a concise set of adult-stage physiological candidates for stage-resolved, tissue-specific, and functional validation.

Acentropinae

Integrative Genomic and Transcriptomic Insights into High-Altitude Adaptation in Changthangi Goats.

The Changthangi goat, native to the high-altitude Ladakh Plateau in northern India, thrives in oxygen-deficient environments above 4,000 m. This study investigated the genetic basis of high-altitude adaptation in Changthangi goats by integrating comparative genomics and transcriptomics, using the tropical lowland Jamunapari goat as a comparative model. Whole-genome sequence data from 15 individuals per breed were analyzed using complementary selection sweep metrics, including nucleotide diversity, Tajima's D, iHS, CLR, XP-EHH, and FST. These analyses identified candidate genomic regions under strong selective pressure, encompassing genes involved in hypoxia sensing (HIF-1α, HIF-2α/EPAS1, EGLN1), angiogenesis (VEGFA, AGGF1, ZEB1), cardiovascular regulation (PRKCB, ESR1, RYR2), mitochondrial and energy metabolism (ACADSB, ACSS3, ACSL1), cellular stress tolerance (BCL2, ATM), and thermogenesis (UCP1, FGF21). Unlike previous caprine studies that primarily infer hypoxia adaptation from genomic signals alone, our study integrates cardiac transcriptomics to demonstrate that genomic selection in Changthangi goats is accompanied by coordinated transcriptional remodeling across interconnected physiological systems in a physiologically relevant tissue. Comparative cardiac transcriptomic profiling revealed concordant expression divergence in genes associated with oxygen transport, vascular remodeling, mitochondrial function, substrate utilization, redox balance, and genome maintenance. This integrative multi-omics framework provides a mechanistic view of caprine high-altitude adaptation and highlights the value of combining genomic selection analyses with tissue-specific transcriptional profiling to resolve complex adaptive traits.

Animals

Whole blood transcriptome profile identifies motor neurone disease RNA biomarker signatures.

Blood-based biomarkers for motor neuron disease are needed for better diagnosis, progression prediction, and clinical trial monitoring. We used whole blood-derived total RNA and performed whole transcriptome analysis to compare the gene expression profiles in (motor neurone disease) MND patients to the control subjects. We compared 42 MND patients to 42 aged and sex-matched healthy controls and described the whole transcriptome profile characteristic for MND. In addition to the formal differential analysis, we performed functional annotation of the genomics data and identified the molecular pathways that are differentially regulated in MND patients. We identified 12,972 genes differentially expressed in the blood of MND patients compared to age and sex-matched controls. Functional genomic annotation identified activation of the pathways related to neurodegeneration, RNA transcription, RNA splicing and extracellular matrix reorganisation. Blood-based whole transcriptomic analysis can reliably differentiate MND patients from controls and can provide useful information for the clinical management of the disease and clinical trials.

Humans

De novo transcriptome assembly and gene expression analysis of Cnidium officinale under high-temperature conditions.

BACKGROUND: The medicinal plant Cnidium officinale (CO) is widespread in Northeast Asia and vulnerable to heat stress. The naturally occurring composition of pharmacological ingredients of CO results in overall physiological consequences; therefore, it is crucial to have a comprehensive understanding of metabolic response to ambient heat in terms of acclimation to estimate how much CO is exposed to threatening environmental conditions. RESULTS: Transcriptome analysis is critical for understanding the consequences of long-term physiological adaptation of CO to abiotic stress. However, transcriptome analysis on this species, particularly under prolonged stress conditions, has remained limited. We employed a temperature gradient tunnel (TGT) to subject CO to high-temperature exposure for four months, enabling us to observe the cumulative effects of heat and assess its acclimation mechanisms. In the absence of genome sequencing data, we performed de novo transcriptome assembly and compared DEGs from temperature treatment plots of a TGT and a growth chamber (GC). Since interpreting transcriptomic data can be complex, we employed a sequential analytical approach, including DEG clustering, GO enrichment, KEGG pathway mapping, miRNA-target gene analysis, and multiple rounds of RNA sequencing validation. DEGs were classified into two categories: genes exhibiting significant fold changes and genes showing significant count changes rather than fold changes. Then, we analyzed the functional roles of DEGs to determine which pathways respond to ambient and stressful high temperatures and validated the findings through cross-comparison with GC. Additionally, we conducted miRNA analysis to investigate post-transcriptional regulation under high temperatures. CO grown under higher ambient temperatures exhibited slight upregulation of pathways related to protein stability and turnover, ABA biosynthesis, and energy production, such as photosynthesis and oxidative phosphorylation. However, under extreme heat stress, most metabolic pathways were downregulated except for those involved in transcription, translation, oxidative phosphorylation and the biosynthesis of cutin, suberin, and wax. CONCLUSION: This study demonstrated that proper clustering of genes based on expression levels and fold changes in two different experimental conditions, along with pathway mapping, may provide a comprehensive understanding of CO's response to heat stress. These insights could contribute to future research on heat tolerance and crop improvement.

Gene Expression Profiling

The chromosome-level genome of Stylosanthes guianensis provides insights into genome evolution and environmental adaptation.

Stylosanthes guianensis is a leguminous forage crop of significant economic importance, primarily distributed in tropical and subtropical regions. It exhibits strong adaptability to various stresses, yet the genetic basis underlying this trait remains unclear. In this study, we constructed the first chromosome-scale reference genome of S. guianensis using a combination of Nanopore and Hi-C sequencing technologies. The assembled genome size is 1254 Mb, with 10 pseudochromosomes. Using Nanopore full-length transcriptome data, we generated high-quality transcript-level gene annotations, identifying 36 585 gene models and 110 601 transcripts. The repetitive sequences in S. guianensis account for 79.16% of the genome, with the extensive expansion of Gypsy elements in long terminal repeats contributing to its genome size enlargement. Comparative genomic and transcriptomic analyses revealed that flavonoid metabolism plays a pivotal role in stress adaptation, providing new insights into the genetic basis of stress tolerance. Additionally, we generated whole-genome methylation profiles under cold treatment and control conditions, offering valuable data for future epigenomic research. These findings provide essential molecular resources for understanding stress resilience in S. guianensis and advancing its molecular breeding.

Genome, Plant

Muscular fiber properties and multi-omics investigation of larval and adult locomotor muscle in Microhyla fissipes.

During metamorphosis, Microhyla fissipes undergoes a critical transition from an aquatic to a terrestrial lifestyle, accompanied by significant remodeling of skeletal muscle. Notably, larval tail muscle degenerates, while adult hindlimb muscle develops. However, the molecular mechanisms that orchestrate these muscle type-specific adaptations to the changing environment remain unclear. In this study, histological observation, transcriptomics, and metabolomics were integrated to compare locomotor muscles from two stages: larval muscle from tail versus adult muscle from hindlimb. Our results revealed that adult muscle fibers exhibited reduced diameter and shorter sarcomere length compared to those of tadpoles. Transcriptomic analysis identified 4103 differentially expressed genes (DEGs), including 2182 up-regulated and 1921 down-regulated genes. Up-regulated genes were mainly involved in energy metabolism and cellular homeostasis pathways, including PPAR signaling and oxidative phosphorylation, whereas down-regulated genes were associated with carbohydrate metabolism and cell proliferation pathways, such as glycolysis/gluconeogenesis and PI3K-Akt signaling. Metabolic profiling indicated a metabolic shift from anaerobic to aerobic energy production, with 57 differential metabolites identified, mainly involved in protein metabolism and insulin-related pathways. Integrated multi-omics analysis further highlighted the AMPK and FoxO signaling pathways play key roles in this process. In conclusion, our findings demonstrate that the metabolic and structural differences between larval and adult skeletal muscles are mediated by AMPK- and FoxO-dependent signaling pathways, providing novel insights into the molecular mechanisms underlying adaptive development and locomotor transition in anuran amphibians.

Animals

Population analysis and immunologic landscape of melanoma in people living with HIV.

PURPOSE: To dissect the clinical and immunological features of people living with HIV (PLWH) diagnosed with melanoma, who have consistently exhibited worse clinical outcomes than HIV-negative individuals (PLw/oH) with the same cancer. EXPERIMENTAL DESIGN: We analyzed electronic health records from 1,019 PLWH and 373,121 PLw/oH diagnosed with melanoma. Demographic and clinical characteristics were compared. Spatial immune transcriptomics (72 immune-related genes) was performed on melanoma tumor samples (n=11), followed by downstream validation using multiplex immunofluorescence (n=15 PLWH, n=14 PLw/oH). RESULTS: PLWH were diagnosed with melanoma at a younger age, had a higher representation of Hispanic and Black individuals compared to PLw/oH, and a decreased survival rate. PLWH also showed a markedly increased risk of brain metastases. PLWH experienced significant delays in initiating immune checkpoint inhibitor (ICI) therapy and had worse survival outcomes following ICI, even after balancing for demographic covariates. Spatial transcriptomics revealed a more immunosuppressive tumor microenvironment in PLWH, with upregulation of immune checkpoints (PD1, LAG3) and reduced expression of antigen presentation markers (HLA-DRB, B2M), with distinct spatial distributions in tumors and their microenvironments. Multiplex immunofluorescence confirmed an exhausted CD8+ T cell compartment in PLWH, including enrichment of PD1intLAG3- and PD1intLAG3+ subpopulations, and a significant accumulation of immunosuppressive myeloid-derived suppressor cells (CD11b+ HLA-DR- CD33+). CONCLUSIONS: Our findings suggest chronic HIV infection fosters a permissive tumor microenvironment that might undermine effective immune responses and contribute to poor clinical outcomes for PLWH with melanoma. Targeting the actionable immune pathways identified in this study could inform tailored therapeutic strategies to mitigate these disparities.

HIV

Genomic and Transcriptomic Profiling of Radiation-Resistant, Locally Recurrent Prostate Cancer.

PURPOSE: The biology of locally radiorecurrent prostate cancer (LRR-PCa) is poorly understood. METHODS AND MATERIALS: We sought to explore the genomic and transcriptomic landscape of LRR-PCa with targeted DNA sequencing and RNA expression analysis from 41 biopsy-proven LRR-PCa tumors from 36 unique patients who had a recurrence at a median interval of 84 months (IQR, 70-124 months). Genomic alteration frequencies and transcriptomic data were compared between the LRR-PCa cohort and treatment-na&#xef;ve patients from the Cancer Genome Atlas (genomic; n = 496) and Gleason grade-at-recurrence-matched patients from the Decipher Genomics Resource for Intelligent Discovery (transcriptomic; n = 22,320). RESULTS: Twenty-five patients (69%) had pathologic upgrading at recurrence (17% vs 64% with Gleason grade 4-5 disease; P < .001). The LRR-PCa cohort demonstrated significantly greater single-nucleotide variations in 29 genes known to be associated with prostate cancer, including several associated with increased aggressiveness and DNA repair: FAT1 (58.5% vs 1.0%), RAD51B (36.6% vs 0.4%), POLQ (34.1% vs 1.4%), KMT2C (34.1% vs 4.9%), BRCA2 (29.3% vs 1.8%), ATRX (26.8% vs 0.8%), and BRCA1 (24.4% vs 0.4%) (Pvalues < .001 for all). The LRR-PCa cohort had a significantly higher Decipher score (median, 0.80 vs 0.66; P = .05) and demonstrated significantly greater basal subtype based on PAM50 (56% vs 20%; P < .001) and lower androgen receptor activity (61% for LRR vs 9%; P < .001). CONCLUSIONS: Overall, these results suggest that LRR-PCa has a distinct genomic and transcriptomic landscape from de novo prostate cancer. Specifically, LRR-PCa has an enrichment in SNVs in genes associated with tumor aggressiveness and/or DNA repair, has higher Decipher scores, a more basal subtype, and has transcriptomic evidence of lower androgen receptor activity and loss of tumor suppressor genes.

Humans

Physiological and transcriptomic responses of sunflower to combined saline-alkali stress.

BACKGROUND: Sunflower (Helianthus annuus L.), an important oilseed crop, is often used as a pioneer species for improving saline-alkali soils. However, the molecular mechanisms underlying sunflower seedling responses to combined saline-alkali stress remain unclear. This study aimed to elucidate the molecular basis of saline-alkali tolerance at the seedling stage by comparing physiological and transcriptomic responses between tolerant and sensitive sunflower hybrids. The saline-alkali tolerant hybrid K-27 and the sensitive hybrid K-7 were used as experimental materials. Root samples were collected at 0, 3, 12, 24, 48, and 96 h after exposure to combined saline-alkali stress (0.5% NaCl + Na2CO3, adjusted to pH 9.0). Physiological parameters, including antioxidant enzyme activities, osmolyte contents, ion concentrations, membrane damage levels, and cell wall components, were measured, followed by transcriptome sequencing analysis. RESULTS: Phenotypic analysis showed that the root length inhibition rate and fresh weight loss rate of K-27 were significantly lower than those of K-7, indicating stronger tolerance. Physiological analysis revealed that K-27 exhibited an inducible antioxidant enzyme response pattern. In addition, K-27 achieved osmotic adjustment through sustained proline accumulation (peaking at 12 h and remaining significantly higher than that of K-7 at 96 h) and exhibited higher basal levels of lignin and hemicellulose. Transcriptome analysis showed that the number of upregulated genes in K-27 was consistently higher than in K-7 at all time points, with 5,283 genes upregulated as early as 3 h after stress exposure. Venn analysis identified 44 core differentially expressed genes (cDEGs) shared between the two genotypes, which were mainly enriched in auxin biosynthesis regulation, phenylpropanoid biosynthesis, and glutathione metabolism. Among them, the benzoic acid carboxyl methyltransferase gene (BAMT) was continuously upregulated in K-27 but persistently downregulated in K-7. In addition, five other genes (encoding fatty aldehyde dehydrogenase, pectin methylesterase inhibitor, glutathione S-transferase, INPP5E, and HXXXD-type acyltransferase) exhibited significantly higher expression levels in K-27. CONCLUSION: K-27 tolerates combined saline-alkali stress through coordinated multi-layered response mechanisms, including inducible antioxidant defense, maintenance of ion homeostasis, sustained osmotic adjustment, and activation of the phenylpropanoid metabolic pathway. Candidate genes such as BAMT may provide potential targets for molecular breeding of saline-alkali tolerant sunflower, although their functions require further experimental validation.

Helianthus

Proteomic Profiling of the Large-Vessel Vasculitis Spectrum Identifying Shared Signatures of Innate Immune Activation and Stromal Remodeling.

OBJECTIVE: Takayasu arteritis (TAK) and giant cell arteritis (GCA), the most common forms of large-vessel vasculitis (LVV), can result in serious morbidity. Understanding the molecular basis of LVV should aid in developing better biomarkers and treatments. METHODS: Plasma proteomic profiling of 184 proteins was performed in two cohorts. Cohort 1 included patients with established TAK (n = 96) and large-vessel GCA (LV-GCA) (n = 35) in addition to healthy control participants (HCs) (n = 35). Cohort 2 comprised patients presenting acutely with possible cranial GCA (C-GCA) in whom the diagnosis was subsequently confirmed (C-GCA, n = 150) or excluded (Not C-GCA, n = 89). Proteomic findings were compared to published transcriptomic data from LVV-affected arteries. RESULTS: In cohort 1, comparison to HCs revealed 52 differentially abundant proteins (DAPs) in TAK and 72 DAPs in LV-GCA. Within-case analyses identified 16 and 18 disease activity-associated proteins in TAK and LV-GCA, respectively. In cohort 2, comparing C-GCA versus not C-GCA revealed 31 DAPs. Analysis within C-GCA cases suggested the presence of distinct endotypes, with more pronounced proteomic changes in the biopsy-proven subgroup. Cross-comparison of TAK, LV-GCA, and biopsy-proven C-GCA revealed highly similar plasma proteomic profiles, with 26 shared DAPs including interleukin 6 (IL-6), monocyte/macrophage-related proteins (CCL7, CSF1), tissue remodeling proteins (TIMP1, TNC), and novel associations (TNFSF14, IL-7R). Plasma proteomic findings reflected LVV arterial phenotype; for 42% of DAPs, the corresponding gene was differentially expressed in tissue. CONCLUSION: These findings suggest shared pathobiology across the LVV spectrum involving innate immunity, lymphocyte homeostasis, and tissue remodeling. Network-based analyses highlighted immune-stromal cross-talk and identified novel therapeutic targets (eg, TNFSF14).

Humans

Comprehensive transcriptomic analysis of BjGL1-knockout Brassica juncea: novel insights into leaf trichome formation.

Brassica juncea is a common cruciferous crop, which can be used not only for oil extraction but also as condiments and medicinal materials. It is regarded by both traditional medicine and modern nutrition science as a food with combined dietary and health promoting value. Leaf trichomes are hair-like structures differentiated from epidermal cells and constitute an important barrier against biotic and abiotic stresses, playing a crucial role in enhancing plant resistance and thus possessing significant scientific relevance. In this study, the phenotype and gene editing site of BjA06.GL1 and BjB02.GL1 knockout mustard T1 generation plants were identified. Then, RNA sequencing was performed to compare the leaf transcriptome profiles between gene-edited lines and wild-type plants, with the aim of elucidating the molecular regulatory mechanisms by which BjGL1 controls leaf trichome development and associated biological processes in mustard. The sequencing data showed that, on average, 90.64% of the reads uniquely aligned to the Brassica juncea (Xuecai) reference genome. A total of 4,604 differentially expressed genes were identified in this study. Compared with the gene knockout mutant, 1,831 genes were significantly upregulated and 2,773 genes were downregulated in mustard leaves with trichomes. The differentially expressed genes were mainly enriched in pathways related to cytochrome P450 (CYP), transporters, environmental adaptation, and plant-pathogen interactions. These pathways are closely associated with secondary metabolite biosynthesis, transmembrane transport, and responses to abiotic stress and pathogen defense. qRT-PCR validation confirmed consistent expression trends of trichome regulatory genes screened from transcriptome data. This study provides an important theoretical basis for elucidating molecular mechanisms potentially contributing to trichome formation in mustard.

Mustard Plant

Genetic variation influences food-sharing sociability in honey bees.

Individual variation in sociability is a central feature of every society. This includes honey bees, with some individuals well connected and sociable, and others at the periphery of their colony's social network. However, the genetic and molecular bases of sociability are poorly understood. Trophallaxis-a behavior involving sharing liquid with nutritional and signaling properties-comprises a social interaction and a proxy for sociability in honey bee colonies: more sociable bees engage in more trophallaxis. Here, we identify genetic and molecular mechanisms of trophallaxis-based sociability by combining genome sequencing, brain transcriptomics, and automated behavioral tracking. A genome-wide association study (GWAS) identified 18 single nucleotide polymorphisms (SNPs) associated with variation in sociability. Several SNPs were localized to genes previously associated with sociability in other species, including in the context of human autism, suggesting shared molecular mechanisms of sociability. Variation in sociability also was linked to differential brain gene expression, particularly genes associated with neural signaling and development. Using comparative genomic and transcriptomic approaches, we also detected evidence for divergent mechanisms underpinning sociability across species, including those related to reward sensitivity and encounter probability. These results highlight both potential evolutionary conservation of the molecular roots of sociability and points of divergence.

Animals

Influence of Gonadal and Chromosomal Sex on the Brain Transcriptome in a Mouse Species with Natural Sex Reversal.

Sex chromosomes are expected to play a role in shaping the transcriptional architecture of sexual dimorphism, through the direct expression of sex-linked genes, by regulating autosomal genes, or in interactions with hormones. Yet, their degree of involvement remains elusive partly because chromosomal sex (e.g. XX/XY) and gonadal sex (ovaries or testes) are usually inextricably intertwined. They are, however, dissociated in the African pygmy mouse, Mus minutoides, in which a feminizing X (X*) has evolved, resulting in three female genotypes (XX, XX*, and X*Y) and one male genotype (XY). Furthermore, all sex chromosomes are fused to autosomes (neo-sex chromosomes: neo-X, neo-X* and neo-Y). Despite complete sex reversal, X*Y females show distinctive phenotypes with greater fertility, divergent maternal care strategies, and the masculinization of some traits (e.g. enhanced aggressiveness). By comparing the brain transcriptome of the four sexual genotypes, we show that differential gene expression is mainly linked to gonadal sex but also, and significantly, to chromosomal sex. Genes influenced by chromosomal sex are overrepresented on sex-linked genomic regions, and some are strong candidates to explain X*Y-specific behavioral and reproductive traits. Our results also suggest the preferential inactivation of the X* chromosome in XX* females, only in the brain, which could explain their trait similarities with XX females. Overall, we show that sex and neo-sex chromosomes have profoundly impacted the brain transcriptome in ways that reflect their new transmission modes, evolutionary trajectories, and resulting genomic conflicts.

Animals

Integrative analysis of transcriptome and chromatin accessibility reveals promoter-proximal regulation and identifies candidate ABC transporters associated with cold stress responses in maize.

BACKGROUND: Low-temperature stress is a formidable environmental constraint that severely limits the growth and productivity of maize (Zea mays L.), particularly during the highly vulnerable early seedling stage. While cold tolerance is a critical agronomic objective, the integrated transcriptional and epigenetic regulatory mechanisms that govern this trait remain largely elusive. Characterizing these coordinated molecular networks is fundamental to the genetic enhancement of cold resilience in maize. METHODS: Using two maize inbred lines contrasting in chilling response (ZHB12 tolerant, B73 sensitive), we performed integrative time&#x2011;course RNA&#x2011;seq and ATAC&#x2011;seq to thoroughly and systematically characterize the precise dynamic interplay between gene expression and chromatin accessibility under cold stress conditions at the seedling stage. RESULTS: Physiological assessments confirmed that ZHB12 possesses superior cold tolerance, manifested by significantly attenuated electrolyte leakage and reduced foliar damage compared to B73. Transcriptomic profiling revealed a massive, time-dependent divergence in gene expression between the two genotypes, with a major regulatory transition identified at 24&#xa0;h of cold exposure. Functional enrichment analysis demonstrated that ZHB12 preferentially activates a robust defense repertoire, including Photosystem II electron transport, diterpenoid biosynthesis, and ATP biosynthetic pathways. Notably, multiple ATP-binding cassette (ABC) transporter genes were coordinately upregulated under chilling, suggesting their potential involvement in cellular homeostasis. ATAC-seq analysis indicated that cold stress is associated with chromatin remodeling in ZHB12, with increased accessibility observed in proximal promoter regions. Integrative analysis identified a core set of dual-responsive genes, in which increased promoter accessibility coincided with transcriptional upregulation. These genes were predominantly enriched in transporter activity and transcriptional regulation, suggesting potential epigenetic link to the superior stress response of ZHB12. CONCLUSION: Our findings reveal extensive transcriptional and chromatin accessibility changes in ZHB12 under cold stress. The observed associations between promoter accessibility and gene activation, particularly in genes involved in transport processes, highlight candidate regulators potentially contributing to cold tolerance. This study provides a molecular framework and identifies high-value candidate genes that may inform future efforts in breeding cold-tolerant maize, pending functional validation.

Zea mays

T2T Genome Assembly and Multi-Omics Data Reveal Terrestrial Adaptation and Mucus Biosynthesis in Tropical Leatherleaf Slug (Laevicaulis alte).

Laevichaulis alte is a slug in the order Systellommatophora that evolved from aquatic ancestors and now faces strong challenges from desiccation, respiration on land, and novel pathogens. Its mucus is essential for water retention, locomotion, and defense. To link terrestrial adaptation with mucus biosynthesis, we generated a gap-free genome assembly of L. alte using PacBio HiFi reads, Oxford Nanopore ultra-long reads, and Hi-C data. The genome shows low heterozygosity and holocentromeric chromosomes. Functional metabolomics revealed marked metabolic shifts between L. alte and the closely related aquatic species Peronia verruculata. In L. alte, differential metabolites were enriched in lipid metabolism, immune regulation, and stress response pathways, consistent with life in a dry and microbe-rich terrestrial environment. Comparative genomics and transcriptomics identified candidate genes linked to mucus secretion and physiological adaptation, including VEGF, ASGR2, and COL6A6. Further analyses highlighted the vascular endothelial growth factor (VEGF) gene family as a key regulator connecting angiogenesis, tissue remodeling, and mucus production pathways in L. alte. Together, this gap-free genome and multi-omics dataset establish a molecular framework that links genomic innovation, mucus biology, and terrestrial adaptation in Systellommatophora, and they offer a basis for understanding ecological niche specialization in land molluscs.

Animals

Time-dependent effects of rapid-acting antidepressants in iPSC-derived neurons from treatment-resistant depression and healthy volunteers.

Rapid-acting antidepressants like ketamine and serotonergic psychedelics show promise for treatment-resistant depression (TRD), but the molecular mechanisms that contribute to their therapeutic effects remain unclear. Induced pluripotent stem cells (iPSCs) offer a platform to model human cortical neurons and investigate drug effects in a human-relevant system. Here, iPSCs from individuals with TRD and healthy volunteers (HVs) were differentiated into mature cortical-like neurons and treated for six and 24&#x2009;h with agents being investigated as rapid-acting antidepressants, including (2&#x2009;R,6&#x2009;R)-hydroxynorketamine (HNK), psilocybin, lysergic acid diethylamide (LSD), and 2,5-Dimethoxy-4-iodoamphetamine (DOI). Bulk and single-cell RNA sequencing assessed global and cell-type-specific transcriptomic responses. Synaptic proteins were evaluated via Western blotting and immunocytochemistry. To validate translational relevance, transcriptomic results were compared to CSF proteomics from ketamine-treated HVs. Despite differing initial pharmacological targets, overall gene expression across all compounds was highly correlated at matched timepoints compared to vehicle control, suggesting shared downstream effects. Both glutamatergic and serotonergic drugs converged on pathways involving inflammation, mTORC1 signaling, and cellular growth. At the single-cell level, (2&#x2009;R,6&#x2009;R)-HNK showed distinct cell-type specific alterations: upregulation in excitatory neurons and concomitant downregulation of inhibitory neuron populations. Differentially expressed genes from (2&#x2009;R,6&#x2009;R)-HNK-treated neurons also overlapped with CSF proteomic signatures from ketamine-treated individuals, supporting the model's translational relevance. This study is the first to assess multiple putative rapid-acting antidepressants in parallel using an iPSC-derived neuron model. Both convergent and drug-specific changes in gene expression and pathway enrichment were observed across diverse compounds, supporting the use of human iPSC-derived neurons in antidepressant drug discovery. Clinical Trial Registry: www.clinical trials.gov, NCT02484456.

Journal Article

Co-option of ancestral stem regulators drove recurrent evolution of underground storage organs.

Geophytes are plants that produce underground storage organs such as tubers, rhizomes, and bulbs, to facilitate asexual reproduction and withstand a myriad of environmental challenges. While the potato (Solanum tuberosum L.) serves as the primary model for studying tuberization, the genetic mechanisms encoding this trait across diverse angiosperm lineages remains unclear. This study utilized a phylogenomic-transcriptomic approach to compare tuber development across nine tuberizing species with five nontuberizing sister taxa. We identified orthologs of key potato tuberization genes that exhibit similar expression in the stolons or tubers of these distant relatives. In nontuberizing species, these orthologs exhibit distinct expression profiles and are primarily expressed in the stem. This suggests that the independent evolution of tubers across angiosperms resulted from shifts in the expression of preexisting genes that led to their co-option. This process, also known as exaptation, occurs when existing genetic suites are recruited for entirely new biological functions. This mechanism stands in contrast to the repeated loss or gain of genes, which has been associated with the origin of other adaptive plant traits. Furthermore, the co-option of the same genes was observed in species with other stem-derived storage organs, such as rhizomes and runners. These findings reveal a conserved evolutionary model for the development of stem-derived geophyte organs that evolved independently across the flowering plants over the past 160 My.

Plant Tubers

KCFtools: rapid alignment-free method for introgression screening and GWAS using k-mer profiles.

MOTIVATION: In the era of multiple genome references, researchers often align sequencing reads against distinct assemblies or even multiple references simultaneously. This enables applications such as the detection of introgressed segments or highly variable genomic regions, which are especially prevalent in large-genome crop species such as lettuce or wheat. However, these applications come at the cost of increased computational burden, inconsistencies in mapping methods, and reduced reproducibility across studies. To address these limitations, we developed KCFtools, a Java-based toolkit that identifies the presence and absence of k-mers in nonoverlapping genomic or transcriptomic windows by comparing query and reference genomes. This alignment-free approach enables the efficient computation of an identity score for each window, thereby facilitating robust detection of introgressed or variable regions across genomes. RESULTS: We systematically evaluated the performance and accuracy of the k-mer-based method implemented in KCFtools, benchmarking it against conventional single nucleotide variation-based introgression detection pipelines. Our results demonstrate that KCFtools effectively captures introgressed segments and structurally diverse regions, even in species with fragmented or highly divergent reference genomes. In addition, we extended KCFtools to generate genotype matrices from k-mer variation tables. These matrices are compatible with genome-wide association studies software and allow the identification of loci associated with phenotypic traits. We showcase the utility of this approach by detecting known and novel associations for downy mildew resistance in lettuce, underscoring the pipeline's potential for high-resolution, reference-agnostic population genetic analysis. AVAILABILITY AND IMPLEMENTATION: https://github.com/sivasubramanics/kcftools.

Software