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PubMed2026

Construction of circRNA-miRNA-mRNA regulatory networks in the intestine of turbot (Scophthalmus maximus) following Vibrio anguillarum infection.

Circular RNAs (circRNAs) play pivotal roles in post-transcriptional regulation by acting as molecular sponges for microRNAs (miRNAs) within the competitive endogenous RNA (ceRNA) network. However, the regulatory mechanisms in teleost immune responses remain poorly understood. In this study, circRNA-miRNA-mRNA networks were investigated in turbot (Scophthalmus maximus) following Vibrio anguillarum infection to elucidate host-pathogen interactions. Through high-throughput sequencing of intestinal tissues, a total of 50 differentially expressed circRNAs (DE-circRNAs) (18 at 2 hpi, 16 at 12 hpi, 16 at 48 hpi), 212 DE-miRNAs (11 at 2 hpi, 70 at 12 hpi, 15 at 48 hpi), and 1774 DE-mRNAs were identified. Functional enrichment analyses (GO/KEGG) revealed significant associations with immune pathways, including the MAPK signaling pathway and gap junction. An integrated circRNA-miRNA-mRNA regulatory network was constructed, highlighting key interactions including novel_circ_0002573/DE-miR-27a-3p/FGB and novel_circ_0002423/novel_347/GNE, which may regulate inflammatory and antibacterial responses. The expression patterns of selected circRNAs, miRNAs and mRNAs were validated using qRT-PCR, confirming the reliability of the sequencing results. Importantly, fibrinogen beta chain (FGB) and CXCR4/CXCL12 signaling were identified as critical immune modulators. These findings provide insights of the ceRNA regulatory networks involved in teleost intestinal immunity and provide potential molecular targets for selective breeding of disease resistance in this species.

Animals↗
PubMed2026

Frequent mutations in the BIRC3 gene promote metastatic potential of nasopharyngeal carcinoma cells through the TRAF2-NF-κB pathway.

Nasopharyngeal carcinoma (NPC) is a head and neck cancer characterized by highly locoregionally invasive behavior attributable to the latent infection with Epstein-Barr virus (EBV) and genomic instability. It is well established that EBV-encoded oncogenic molecules actively contribute to the malignant behavior of NPC cells. However, the mechanism by which aberrant genomic alterations enable NPC cells to become aggressive remains largely unknown. In the present study, whole-exome sequencing (WES) revealed that the gene encoding the baculoviral IAP repeat-containing 3 (BIRC3) protein was frequently mutated in circulating tumor cells (CTCs) but not in paired primary tumor cells from patients with metastatic NPC. A minigene assay indicated that the c.637 A > G mutation disrupted normal mRNA splicing, resulting in the partial deletion of Exons 2 and 3 and altered stability of BIRC3 mRNA. In vitro experiments demonstrated that ectopic expression of the BIRC3c.637A>G mutant enhanced NPC cell invasive properties, including proliferation, resistance to apoptosis, migration, and invasion. Furthermore, overexpression of wild-type BIRC3 promoted invasive characteristics in NPC cells through the TRAF2-NF-κB signaling axis. In summary, BIRC3 acts as a regulator of the malignant features of NPC cells. Frequent BIRC3 mutations in CTCs, such as the c.637 A > G mutation, further enhance the metastatic potential of disseminated NPC cells by inducing aberrant alternative splicing. These findings suggest the therapeutic feasibility of targeting the BIRC3/TRAF2/NF-κB axis in the treatment of NPC.

Humans↗
PubMed2026

The gonadal matrisome and its correlation with sex change in the ricefield eel Monopterus albus.

The matrisome is a comprehensive list of genes in the genome of an organism, which encodes proteins constituting or interacting with the extracellular matrix (ECM). The gonadal ECM is important for folliculogenesis and spermatogenesis. This study characterized the composition of the matrisome and the expression of matrisome genes in the gonad of ricefield eel, a protogynous sex-changing teleost, during sex change. A total of 838 matrisome genes were identified in the genome of ricefield eel through an in-silico orthology-based approach, of which 482, 443, 429, and 570 matrisome genes were shown to be expressed in the gonads of female (F), early intersexual (EI), mid-intersexual (MI), and late intersexual (LI) fish, respectively. Differentially expressed matrisome genes (DEMGs) were observed across all the sexual stages as well as in each category of ECM components. Analysis of DEMGs in the comparison between EI and F revealed dramatic upregulation of adam8a, mmp9, and s100a11 while downregulation of col4a5, col15a1b, clec3ba, f13a1, and ccl44, which were further confirmed by qPCR analysis. Together, these findings revealed significant changes in the expression of many matrisome genes, particularly three regulator genes, adam8a, mmp9 and f13a1, as female ricefield eels initiate sex change, suggesting that gonadal tissues undergo dramatic remodeling involving the regression of ovarian tissues and the development of testicular tissues to facilitate this process. These data provide valuable resources for further unraveling the roles of matrisome genes in gonadal development of ricefield eel and other vertebrates.

Animals↗
PubMed2026

Spatial transcriptomics of Ciona adult brains reveals functional zonalization and insights into neural gland function.

The ascidian Ciona is a pivotal chordate model for illuminating the evolutionary origins of the vertebrate brain. Here, spatial transcriptomics of the adult Ciona neural complex, combined with image-based computational super-resolution mapping, resolved distinct tissue domains including the cerebral ganglion, neural gland, ciliated funnel, neural gland duct/dorsal strand, and body wall muscle. Within the cerebral ganglion, high-resolution mapping revealed clear molecular zonalization separating the cortex and medulla, alongside regional specialization within the cortex itself. The neural gland exhibited localized enrichment of genes associated with extracellular matrix and cell-cell interactions. These spatial features suggest that the neural gland functions as a homeostatic and signaling interface, reminiscent of primitive vertebrate meninges or choroid plexus. Overall, this spatially defined gene expression map provides a foundational framework for understanding functional regionalization in the tunicate brain and its evolutionary relationship to vertebrate nervous systems.

Ciona↗
PubMed2026

Emergence of Babesia naoakii infection in Indonesian domestic cattle, a new host record in water buffaloes, and characterization of complete mitochondrial protein-coding genes.

Babesia (B.) naoakii, previously referred to as Babesia sp. Mymensingh, is a recently characterized tick-borne haemoprotozoan parasite of cattle. In Indonesia, we first reported its presence in 2022 from clinically affected cattle in Central Java. To investigate the wider epidemiology of this neglected ruminant-associated Babesia species, we surveyed apparently healthy cattle (Bos indicus) and water buffaloes (Bubalus bubalis) across three districts of Java, Indonesia. A PCR assay targeting the B. naoakii-specific apical membrane antigen 1 (ama1) gene detected the parasite occurrence in 34.39% of assessed cattle (87/253; 95% CI: 28.80-40.44%) and 30.77% of water buffaloes (12/39; 95% CI: 18.47-46.52%). These results represent the first record of B. naoakii infection in water buffaloes in the country and confirm that the parasite circulates in subclinically infected bovine hosts. To characterise this apicomplexan parasite further at the molecular level, we assembled in full length the three mitochondrial protein-coding genes (PCGs): cytochrome c oxidase subunits 1 (cox1) and 3 (cox3), as well as cytochrome b (cytb). These genes were reconstructed by next-generation sequencing of blood DNA collected during the acute haemolytic-phase of B. naoakii infection, from calves that subsequently succumbed to the disease in the endemic area. Phylogenetic analyses of the concatenated amino-acid sequences of cox1, cox3, and cytb placed the Indonesian isolates within a well-supported monophyletic clade, distinct from all previously characterised ruminant-associated Babesia species and sister to the Babesia bigemina/Babesia ovata lineage. This placement confirmed species identity and reinforced the genetic distinctiveness of B. naoakii in Indonesia. Notably, although B. naoakii circulates in peripheral blood and mirrors the diagnostic behaviour of the mild pathogen B. bigemina, its clinical impact more closely resembles that of the severe pathogenic B. bovis, particularly in young animals. This diagnostic-clinical discordance highlights the need for B. naoakii-specific molecular surveillance and species-level differentiation in regions of co-endemicity. Given the high prevalence in subclinically B. naoakii-infected adults, the documented severity of babesiosis in calves, and the potential for substantial economic losses, broader epidemiological investigations and species-specific control measures for B. naoakii are urgently performed. The same holds true for future epizootiological investigations of underdiagnosed B. naoakii-infections possibly circulating in Indonesian endemic ruminant bovids such as the banteng (Bos javanicus), the lowland anoa (Bubalus depressicornis) and the tamaraw (Bubalus mindorensis).

Animals↗
PubMed2026

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↗
PubMed2026

Ecr positively regulates activity of the PhoQ/PhoP signalling system in Klebsiella pneumoniae.

BACKGROUND: The rising prevalence of polymyxin resistance in multidrug-resistant Klebsiella pneumoniae presents a critical situation with limited therapeutic options. METHODS: Methods Genomic sequencing of 15 clinical polymyxin-resistant K. pneumoniae strains with multidrug resistance revealed that MgrB inactivation, predominantly disrupted by insertion sequences (ISs) in the IS1, IS4, and IS5 families, was the leading cause of polymyxin resistance. Comparative transcriptomics of wild-type, ΔmgrB, and ΔmgrBΔphoP were performed to elucidate the MgrB-PhoPQ regulatory network. RESULTS: This study conducted a system-wide analysis of the regulatory network and identified a species-specific PhoPQ regulon in K. pneumoniae.Beyond the classical MgrB-PhoPQ-ArnBCADTEF pathway, we identified a previously unannotated PhoPQ-regulated gene, 144 bp LN739_RS09850, encoding an Ecr homologue from Enterobacter cloacae. This protein has been reported to confer colistin heteroresistance, with the underlying mechanism not yet functionally validated. This study revealed that overexpression of Ecr homologues decreased colistin susceptibility in both K. pneumoniae and E. cloacae, but this phenotype was abolished upon phoP deletion, confirming PhoP's essential role. Consistent with this dependency, comparative transcriptomics of Ecr-overexpressing K. pneumoniae vs. control revealed significant upregulation of mgrB, phoPQ, arnBCADTE, and pmrD. Two-hybrid bacterial assays further demonstrated direct Ecr-PhoQ interaction. Electrophoretic mobility shift assay confirmed that PhoP directly binds to the ecr promoter in vitro, and a β-galactosidase reporter assay demonstrated that PhoP enhanced ecr promoter activity, indicating that PhoP regulates ecr expression by directly controlling its transcription. CONCLUSION: Collectively, these findings suggest that PhoP may directly activate the transcription of Ecr, with Ecr feedback activating the PhoPQ system via interaction with PhoQ, leading to induction of the arn operon and consequent polymyxin resistance.

Klebsiella pneumoniae↗
PubMed2026

[Pathogenicity analysis and prenatal genetic counseling for five Chinese pedigrees harboring a hemizygous c.-32C>G variant of FGF13 gene].

OBJECTIVE: To explore the pathogenicity and prenatal counseling strategies for five Chinese pedigrees harboring a hemizygous c.-32C>G (NM_001139500.2) variant of fibroblast growth factor 13 (FGF13) gene. METHODS: Five Chinese pedigrees found to carry a hemizygous c.-32C>G variant of the FGF13 gene at the Prenatal Diagnosis Center of Henan Provincial People's Hospital between January 2024 and January 2025 were selected as study subjects. The pedigrees had undergone prenatal diagnosis for a family history of genetic disorders, abnormal fetal ultrasound findings, or advanced maternal age. A retrospective analysis was carried out, wherein clinical data for all members of the pedigrees were obtained through the medical records system and outpatient visit system. Peripheral blood samples were collected from all pedigree members, and amniotic fluid samples were obtained from the probands. Following extraction of genomic DNA, prenatal diagnosis was performed using chromosomal microarray analysis (CMA) and trio whole-exome sequencing (trio-WES). Sanger sequencing was used to determine the carrier status for the candidate variant, and Mini-Mental State Examination (MMSE) was used to assess the cognitive function of hemizygous individuals carrying the FGF13 gene c.-32C>G variant. Pathogenicity of candidate variant was assessed based on guidelines from the American College of Medical Genetics and Genomics (ACMG). This study was approved by the Medical Ethics Committee of the hospital (Ethics No.: 2021-171). RESULTS: CMA and trio-WES revealed no pathogenic variants in all probands, whilst trio-WES and Sanger sequencing had identified 11 male individuals carrying a hemizygous c.-32C>G variant of the FGF13 gene from the five pedigrees, which included six adult males, a young boy, and four fetuses. One fetus had undergone termination of pregnancy due to hydrocephalus, one was born pre-term at 34+1 weeks of gestation owing to maternal hypertension, and other two were delivered at full term. Follow-up of the survived males revealed no phenotypic manifestations related to language or intellectual impairment. Among these, three adult males underwent the MMSE assessment, all of whom showed normal cognitive function. Search of the gnomAD database suggested the carrier frequency of FGF13 c.-32C>G variant in the East Asian population to be 0.125%, with 11 hemizygous males documented. Three male patients harboring the variant showed severe intellectual disability. Both in vitro and in vivo studies suggested that it could reduce the translation levels of FGF13 protein. Based on the ACMG guidelines, it was classified as variant of uncertain significance (BS4+PS3_Supporting). CONCLUSION: There is insufficient evidence to classify the FGF13 c.-32C>G as a pathogenic variant in clinical practice, and its presence should not be considered an indication for pregnancy termination due to major birth defects.

Adult↗
PubMed2026

Investigation of Fatty Acid Metabolism-Associated Molecular CPOX and the Underlying Mechanism in Follicular Lymphoma.

Dysregulated lipid metabolism is a key driver of follicular lymphoma (FL). This study aimed to explore the lipid metabolism-related genes (LMRGs) and clarify the underlying roles and mechanisms in FL. Bioinformatics methods, including differential analysis, WGCNA, machine learning, and Mendelian randomization, were utilized to select the LMRGs in FL. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were conducted to investigate the function of the key LMRG. Receiver operator characteristic (ROC) was used to evaluate the diagnostic value of the key gene CPOX. A pan-cancer analysis investigated CPOX's expression level and immune correlations. In vitro experiments using FL cell lines (WSU-FSCCL, DOHH2) validated CPOX expression, and CPOX knockdown in DOHH2 cells was used to assess its impact on viability, migration, invasion, and fatty acid metabolism. CPOX was confirmed to be a risk factor, significantly overexpressed in FL, and exhibited effective diagnostic ability in FL (AUC = 0.731). Functional analysis linked CPOX to mitochondrial function, oxidative phosphorylation, and heme metabolic process. Pan-cancer indicated the dysregulated CPOX across multiple cancers and closely correlation with immune characteristics. Experimentally, CPOX was higher in the more invasive DOHH2 cells; and CPOX knockdown suppressed FL progression and reduced lipid droplet formation, triglyceride, total cholesterol, and free fatty acid levels. In conclusion, this study fills the gap in understanding the significance of lipid metabolism-related molecules in FL, and innovatively proposes that CPOX is a risk factor for FL. Knockdown of CPOX inhibits the FL progression, which is regulated by fatty acid metabolism.

Lymphoma, Follicular↗
PubMed2026

Seventeen-year follow-up of hypophosphatasia diagnosed in middle-aged siblings harboring a novel intronic and a rare missense ALPL gene mutation.

Hypophosphatasia (HPP) is the rare inborn-error-of-metabolism that features impaired mineralization of the skeleton and teeth due to a deactivating mutation or mutations of the gene ALPL which encodes the tissue-nonspecific isoenzyme of alkaline phosphatase (TNSALP). We report 17-year follow-up of twin sisters and a brother referred in middle-age for painful proximal femoral "stress fractures" and then diagnosed with HPP. They reported generalized muscle and bone pain, metatarsal fractures, arthropathy and, since childhood, tooth loss. Their concordant findings were explained by compound heterozygosity in ALPL for a rare maternal missense mutation (c.1403C > T, p.Ala468Val) in exon 12, together with a novel presumably paternal change (c.863-14G > A) predicting a cryptic mRNA splice site in intron 8. Fractures continued during follow-up until one sister received a three-and-one-half-year course of hydroxyapatite-targeted TNSALP supplementation therapy (asfotase alfa) during which substantial improvement occurred in her clinical, biochemical, and functional parameters as well as quality of life. Following subsequent unplanned treatment cessation she suffered significant clinical deterioration, including new fractures and loss of mobility. Her bone histopathology documented osteomalacia. Treatment resumption restored its benefits. Among ten asymptomatic family members evaluated in this four-generation kindred, eight were carriers heterozygous for either ALPL mutation. Those harboring the maternal missense defect manifested mild hypophosphatasemia, suggesting a dominant-negative mutation effect. This experience underscores the importance of in-depth phenotyping and then clinical follow-up to characterize ALPL variant combinations, and for maintaining effective asfotase alfa treatment.

Humans↗
PubMed2026

Whole-transcriptome RNA sequencing and ceRNA network analyses provide novel insights into the antibacterial immune response of Hippocampus abdominalis against Vibrio harveyi.

Long non-coding RNAs (lncRNAs) stand as newly-arisen molecular types that exert regulatory effects, able to operate as competitive endogenous RNAs (ceRNAs) to engage microRNAs (miRNAs) in interaction, resulting in the recovery of target mRNA expression and activity. Increasing evidences indicate that the ceRNA network affects various biological processes in mammals, including development, cellular differentiation, metabolism, immune response, and disease pathogenesis. In teleost fish, the lncRNA-miRNA-mRNA regulatory networks have been reported occasionally. However, up to now, the roles of lncRNAs in the big-belly seahorse (Hippocampus abdominalis) remains unclear. In this study, we reported for the first time, via whole-transcriptome RNA sequencing, the lncRNA mediated ceRNA regulatory network in Vibrio harveyi-infected H. abdominalis. A total of 4197 differentially expressed mRNAs (DE-mRNAs), 1317 DE-lncRNAs, and 183 DE-miRNAs were identified. Furthermore, the crosstalk between miRNAs and lncRNAs as well as between miRNAs and mRNAs was inferred based on the negative correlations between miRNAs and their target lncRNAs/mRNAs. A core immune associated lncRNA-miRNA-mRNA putative regulatory network was thus constructed, comprising 211 lncRNA-miRNA and 224 mRNA-miRNA pairs. In conclusion, our findings provide an integrative overview of the ceRNA regulatory networks on the underlying immune responses to V. harveyi infection in the big-belly seahorse, and offer a solid theoretical foundation for the comparative immunological research of teleost fish.

Animals↗
PubMed2026

Contrasting redox-related physiological responses associated with HaGATA23 and HaGATA36 during Orobanche cumana parasitism in sunflower (Helianthus annuus L.).

Helianthus annuus is an economically important Asteraceae species used for seed oil production and ornamental purposes, but its production is seriously affected by the root-parasitic plant Orobanche cumana. GATA transcription factors are zinc-finger DNA-binding regulators involved in plant development and stress adaptation. However, the molecular characteristics of GATA transcription factors in Helianthus annuus and their contribution to Helianthus annuus -Orobanche cumana interaction remain poorly understood. Here, 36 HaGATA members were retrieved from the Helianthus annuus genome and classified into four phylogenetic clades. Chromosomal placement, collinearity, gene structure, motif composition, and promoter elements varied among the 36 HaGATA members, indicating evolutionary conservation coupled with functional diversification. Expression analysis and RT-qPCR analyses revealed differential expression patterns among HaGATA genes under O. cumana stress, with HaGATA23 markedly downregulated and HaGATA36 strongly upregulated. Overexpression of HaGATA23 was associated with increased malondialdehyde (MDA) accumulation and unfavorable changes in antioxidant enzyme activities, whereas its silencing showed the opposite physiological tendency. In contrast, overexpression of HaGATA36 reduced malondialdehyde accumulation, increased peroxidase (POD), catalase (CAT), and superoxide dismutase (SOD) activities, while its silencing showed the reverse tendency. These results indicate that HaGATA23 and HaGATA36 are candidate genes associated with contrasting redox-related physiological responses during O. cumana stress. This work provides evidence that GATA transcription factors are associated with redox-related physiological responses in sunflower under O. cumana treatment and identifies HaGATA23 and HaGATA36 as functionally divergent candidate genes for further validation.

Helianthus↗
PubMed2026

Moderate expression and activity of flocculins underlie the characteristic flocculation phenotype of Saccharomyces pastorianus.

Flocculation is a key technological trait in lager brewing, governing fermentation performance, yeast recovery, and beer quality. In the allo-aneuploid hybrid yeast Saccharomyces pastorianus, the genetic basis of flocculation remains poorly resolved due to its complex dual sub-genome architecture. Here, we systematically re-annotated and functionally characterized the complete FLO gene repertoire of the Group II strain CBS 1483. Thirteen FLO genes were identified, including allelic variants and a previously uncharacterized adhesin, Flo12, containing a Hyphal_reg_CWP domain instead of the canonical PA14 lectin-binding domain. Structural modeling revealed strong conservation of Ca²+-binding residues in PA14 domains, alongside repeat-region diversification likely contributing to functional variability. Using optogenetic expression in a FLO-null background, we demonstrated that SpcI-FLO9-1 and SpcI-FLO9-2_1 are the strongest drivers of flocculation, exhibiting NewFlo-like sugar sensitivity. Transcriptomic analysis during 17°P wort fermentation showed dynamic induction of these genes coinciding with flocculation onset. Surprisingly, deletion of both loci in CBS 1483 did not abolish but only delayed sedimentation in wort, accompanied by improved maltose utilization and attenuation. These findings reveal functional redundancy and compensatory mechanisms within the FLO network of lager yeast, highlighting the genetic complexity underlying flocculation, and providing a molecular framework to inform yeast selection, strain development, and optimization of the lager fermentation processes.IMPORTANCEFlocculation, the process by which yeast cells aggregate and settle, is essential for producing clear, high-quality lager beer, and for efficient yeast recovery during brewing. However, the genetic basis of this trait in lager yeast has remained poorly understood because these strains possess unusually complex hybrid genomes. In this study, we systematically identified and characterized the complete set of flocculation genes in the industrial lager yeast Saccharomyces pastorianus CBS 1483. We demonstrated that lager yeast flocculation is not controlled by a single dominant gene, but instead emerges from the combined action of several moderately active adhesion proteins that are expressed at low levels during fermentation. Surprisingly, deleting the two strongest candidate genes only delayed, rather than eliminated, sedimentation, revealing a robust compensatory network that preserves brewing performance. These findings refine the current understanding of yeast flocculation and provide a molecular framework for developing brewing strains with improved fermentation efficiency, product consistency, and flavor quality.

Saccharomyces pastorianus↗
PubMed2026

Multi-omics analysis reveals stage-associated differences in gut immunity and microbiota between juvenile and adult common carp (Cyprinus carpio).

In vertebrates, the development of intestinal immunity is closely associated with dynamic changes in the gut microbiota. However, stage-associated differences in intestinal immunity and gut microbial communities remain poorly characterized in teleost fish. In this study, transcriptomic analysis combined with 16S rRNA gene sequencing was employed to characterize intestinal immunity and gut microbial communities in juvenile and adult common carp (Cyprinus carpio). Transcriptomic profiling revealed marked developmental differences in intestinal immune function. Juvenile carp exhibited a predominantly innate immune phenotype, characterized by elevated expression of pro-inflammatory cytokines, antimicrobial peptides, and lysozyme-related genes. This immune profile was accompanied by enhanced mucosal barrier function and a relatively pro-inflammatory intestinal environment. In contrast, adult carp displayed increased expression of genes associated with adaptive immunity, suggesting that adult common carp exhibit relatively stronger adaptive immune characteristics than juvenile fish. Gut microbiota analysis demonstrated significant stage-dependent differences in microbial diversity and community composition. Juvenile fish were enriched with bacterial taxa potentially associated with innate immune activation, whereas adult fish harbored distinct microbial communities linked to intestinal homeostasis and barrier maintenance. Furthermore, correlation analyses identified significant associations between specific microbial taxa and innate immune-related gene expression, suggesting a close association between gut microbiota composition and intestinal immune characteristics in juvenile and adult common carp. Collectively, these findings reveal stage-associated differences in intestinal immunity and gut microbial communities between juvenile and adult common carp, thereby providing insights into intestinal immune characteristics at different developmental stages in teleost fish.

Animals↗
PubMed2026

Integrative genomic and transcriptomic analyses identify key regulators of skin pigmentation in Larimichthys crocea.

The yellow body coloration of large yellow croaker (Larimichthys crocea) constitutes a crucial economic trait, yet its underlying genetic regulatory mechanisms remain poorly understood. This study systematically elucidated the molecular basis of body color variation by integrating genome resequencing and skin transcriptome analyses, combined with the contextual analysis of key pigmentation-related genes and phenotypic histological validation. 200 phenotyped individuals (including yellow-selected lines, F1 progeny, and normal control groups, all derived from a well-characterized aquaculture stock) identified 39 significantly associated SNPs (-log₁₀(P) ≥ 6), mapping to multiple candidate genes. These genes were significantly enriched in pathways related to pigment deposition (GO:0033059), melanosome organization (GO:0032438), melanogenesis, and tyrosine metabolism. Cross-developmental stage transcriptome analysis revealed 2395 differentially expressed genes (DEGs). Multi-omics integration identified eight overlapping candidate genes, including tyrp1, slc45a2, oca2, and dgat2, among which tyrp1 was prioritized for in-depth validation based on its core regulatory role in eumelanin synthesis, significant SNP association signal, and consistent downregulation in transcriptomic data. Experimental validation demonstrated that the g.895C > T mutation in exon 2 of tyrp1b was strongly significantly associated with the yellow phenotype: the frequency of mutant genotypes (TT/CT) reached 92.86%in the yellow-selected group, whereas the control group exclusively exhibited the wild-type genotype (CC). qPCR confirmed significantly downregulated tyrp1b expression in the skin of yellow individuals, consistent with the transcriptome trend. Histological and stereomicroscopic observations of skin tissues further validated the physiological basis of the yellow phenotype, revealing a significant reduction in melanophore number and abnormal melanosome morphology in yellow-phenotype individuals, accompanied by increased xanthophore density. These results suggest that tyrp1b mutation is strongly associated with the yellow phenotype. However, the presence of a wild-type CC individual in the yellow group indicates that this mutation is not strictly required for yellow coloration, suggesting that other genetic or environmental factors may also contribute to the phenotype, Additionally, downregulation of the carotenoid metabolism gene bco2 coupled with upregulation of xdh, together with the functional changes of slc45a2 and oca2, may synergistically promote xanthophore pigment deposition, contributing to the yellow phenotype. As melanin synthesis in large yellow croaker relies on the conserved tyrosinase pathway and transporter proteins, mutations in associated genes (tyrp1b, slc45a2, oca2) represent a primary underlying cause for the loss of melanin-based coloration and transition to a yellow phenotype in L. crocea. These findings provide key molecular targets and a theoretical foundation for molecular breeding of body color in this species, and also enrich the understanding of xanthism regulatory mechanisms in teleosts.

Animals↗
PubMed2026

Distinct molecular responses to acute cold exposure revealed by comparative transcriptomic and metabolomic profiling in the bay scallop Argopecten irradians.

Acute cold stress can elicit distinct molecular responses even when bay scallop populations show similar phenotypic outcomes. We compared a seventh-generation fast-growing bay scallop line (BS) with a commercial control population (CC) during a 72-h acute cold exposure at -1 ± 0.3 °C. RNA-seq was used as the discovery layer, representative BS cold-responsive genes were evaluated by qRT-PCR, and paired LC-MS profiles provided a comparative metabolic layer. At baseline, 138 genes differed between BS and CC; after cold exposure, 134 of these baseline differences disappeared and 61 of 65 cold-state differences newly emerged. BS showed a larger transcriptomic response magnitude than CC, with 1129 cold-responsive genes compared with 28 genes in CC, and this ordering remained robust across multiple sensitivity analyses. Survival after 72 h was identical in BS and CC (83/90, 92.2% in each population). Biochemical responses were time-dependent and marker-specific: CAT, LZM, T-SOD and T-AOC showed population-by-time interactions, whereas GSH-Px and MDA did not, and the 72-h differences were not consistently favourable to BS. Metabolomic cold effects were strongly concordant between populations, and no feature showed a significant population-by-cold interaction. Features putatively assigned to arachidonic acid metabolism were enriched, but this provider-annotated pathway signal remains exploratory because authentic-standard confirmation was not performed. These findings indicate population-specific differences in molecular responsiveness but do not establish superior cold tolerance in BS.

Animals↗
PubMed2026

Cis-regulatory variation in the MdCKX6 promoter is associated with allele-specific expression and fruit size in apple.

Fruit size is a key determinant of apple fruit quality and market value and is strongly influenced by phytohormone-regulated cell proliferation and expansion during early fruit development. Cytokinin oxidase/dehydrogenase (CKX) enzymes regulate cytokinin homeostasis by irreversibly degrading active cytokinins, but the contribution of natural variation in CKX genes to fruit size remains poorly understood. Here, we identified MdCKX6 as a candidate regulator of fruit growth in apple (Malus domestica). MdCKX6 exhibited pronounced allele-specific expression during fruit development in the cultivar 'Royal Gala'. Sequence analysis identified a promoter SNP associated with differential promoter activity and allele-specific expression. Genotyping of diverse apple cultivars and wild Malus accessions revealed a significant association between MdCKX6 promoter genotype and fruit size. Cultivars carrying low-expression alleles produced larger fruits, whereas high-expression alleles were associated with smaller fruits. To investigate gene function, MdCKX6 was overexpressed in tomato, resulting in reduced fruit size. Histological analyses of the transgenic tomato fruit revealed smaller pericarp cells. Transcriptome analysis of transgenic fruits revealed widespread changes in genes associated with cell-cycle regulation, cell wall modification, hormone-related processes, and transcriptional regulation. Together, these results identify MdCKX6 as a potential negative regulator of apple fruit growth and reveal an association between cis-regulatory variants, gene expression, and fruit size. This study provides new insights into the role of cytokinin metabolism in fruit development and highlights regulatory variation in MdCKX6 as a potential target for apple breeding.

Malus↗
PubMed2026

Liver transcriptome analysis revealed multiple immune processes and lipid metabolism pathways involved in the defense response of the turbot (Scophthalmus maximus) against Aeromonas salmonicida.

Aeromonas salmonicida is a significant pathogen causing notable economic losses in Scophthalmus maximus aquaculture. This study utilized Illumina sequencing technology to examine the transcriptional response characteristics of S. maximus liver at 24 h following A. salmonicida infection. A total of 2363 differentially expressed genes (DEGs) were identified when compared to the negative control group. The immunity-related Toll-like receptor signaling pathway, NOD-like receptor signaling pathway, as well as metabolism-related PPAR signaling pathway and insulin signaling pathway, were notably enriched. Significant differences exist in the expression of key genes within the PPAR pathway, particularly cd36, acsl4a, pparαa, and plin2, all of which mediate the interaction between lipid metabolism and the immune response. These results offer valuable insights into the immunometabolic regulatory mechanism of S. maximus response to A. salmonicida infection.

Animals↗