Amblyomma sculptum is a major tick species in southeastern Brazil and an important vector in the epidemiology of Brazilian Spotted Fever (BSF). This study characterized the bacterial microbiome of free-living A. sculptum ticks in a BSF-endemic area, focusing on differences among developmental stages and sexes, and investigated rickettsial agents using 16S rRNA gene (V3-V4) sequencing. A total of 154 ticks were collected and analysed as 13 pooled samples grouped by stage and sex. Sequencing identified a diverse bacterial community of 180 genera, dominated by Sphingomonas, Nocardioides, Actinomycetospora and Methylobacterium, alongside genera of potential zoonotic relevance such as Rickettsia, Anaplasma, Ehrlichia and Coxiella, mainly in nymph pools. Alpha and beta diversity analysis showed that microbial community composition differed among stages and sexes, with adult males exhibiting higher richness and compositional dispersion, whereas nymphs showed reduced diversity and tighter clustering. Because 16S sequencing does not allow species-level identification of rickettsiae, positive samples were further analysed by PCR amplification and sequencing of the gltA gene, which identified Rickettsia bellii. Together, these results highlight stage- and sex-associated patterns in the microbiome of free-living A. sculptum and support the use of integrated microbiome profiling and targeted rickettsial detection in ecological and epidemiological studies of tick-borne diseases.

Colostrum is crucial for the survival and health of neonatal calves, providing passive immunity and influencing early gut microbial colonization. This study evaluated the impact of three colostrum sources: fresh maternal colostrum (FMC), frozen maternal colostrum (FC), and colostrum replacer (CR) on the development of the fecal microbiota in Holstein calves. Fifteen newborn calves were randomly assigned to one of three treatments (n = 5 per group). Fecal samples were collected at birth (meconium), daily during the first seven days of life, and at weeks 2, 4, 8 (weaning), and 10 (post-weaning). Microbial composition was assessed using 16 S rRNA gene sequencing. Alpha diversity increased over time (P < 0.001), with no significant differences observed among treatments. Microbiota succession followed a consistent trajectory across all groups, characterized by an early dominance of Escherichia/Shigella, which gradually transitioned to increased relative abundances of Lactobacillus, Bacteroides, and Faecalibacterium over time. Notably, calves fed FMC showed a significantly higher fecal relative abundance of Lactobacillus during the first three days of life (excluding day 0, meconium) compared to those receiving FC (P = 0.046) or CR (P = 0.44), although the overall bacterial community structure was primarily influenced by calf age. These findings suggest that while colostrum source does not impact overall microbial diversity, it may modulate early colonization by beneficial bacteria. Providing fresh maternal colostrum may promote more favorable microbiota programming during the neonatal period.

The integration of multiple omics strategies represents a transformative paradigm in farm animal genetics and breeding. By capturing molecular complexity across biological layers, integrative omics offers new opportunities to reveal the regulatory mechanisms underlying economically important traits. Here, we characterize the hepatic transcriptomic landscape of Nelore cattle and its relationship with meat and carcass quality phenotypes. For that, we integrated gene expression data, co-expression networks, expression quantitative trait locus (eQTL) mapping, single-nucleotide polymorphism (SNP)–phenotype associations, chromatin accessibility, and transcription factor motif analyses using hepatic RNA-seq data from 90 animals and assay for transposase‑accessible chromatin using sequencing (ATAC-seq) data from two animals. Weighted gene co-expression network analysis (WGCNA) identified 10 gene modules associated with our phenotypes of interest, particularly the blue module (r = −0.4), which is linked to meat color and enriched in insulin and mTOR signaling pathways. eQTL mapping revealed 1,198 cis- and 39,227 trans-eQTLs (false discovery rate [FDR] < 0.05), including hotspots on chromosome 25. Notably, rs449155362 was found to regulate 848 genes, within them MLXIPL, a transcription factor involved in glucose and lipid metabolism. Phenotype–eQTL associations revealed 54 SNPs (FDR < 0.05) related to meat and carcass traits, among which rs110069409, within an open chromatin region, modulates PLA2G2D1 expression and was associated with meat color (yellowness 24 h after the slaughter—b*₀), representing a convergence point across regulatory layers. These findings provide novel insights into the multilayered genetic architecture of the liver that controls meat quality traits in beef cattle, supporting the use of integrative omics to guide functional genomic selection.

The interplay between diet and the microbiome in ruminants significantly influences livestock productivity and environmental sustainability. Among these effects, methane emissions—a potent greenhouse gas produced by rumen microbes—remain a major challenge, reinforcing the need for effective mitigation strategies. However, how dietary modifications reprogram microbial communities and their subsequent influence on host metabolism and methane production remains insufficiently understood. Here, we investigated the effects of diet on the ruminal and fecal microbiomes of young Nellore bulls, alongside host transcriptomic responses in key metabolic tissues, using a multi-tissue, diet-specific systems biology approach. Our gene co-expression and microbial co-abundance network analyses identified distinct microbial and transcriptomic signatures shaped by diet. Notably, Megasphaera and Butyrivibrio exhibited marked adaptations to dietary changes. Furthermore, methane emissions were associated with distinct sets of genes and microbial taxa depending on diet, with 42 genes and Eubacterium linked to methane in the traditional diet, whereas 18 distinct genes and Ruthenibacterium were associated with methane in the alternative diet. Our findings reveal an intricate, multifaceted, and diet-dependent interplay between microbiome composition, host gene expression, and metabolic processes, offering insights into microbial and molecular targets for optimizing livestock efficiency and sustainability.

Above ground botanical composition in biodiverse ecosystems can be reliably estimated through taxonomic and morphological identification, but below ground identification is more challenging due to the absence of distinctive root characteristics. In this study, we calibrated and applied a chloroplast DNA-based method to quantify the botanical composition of root mass in tropical forage grass mixtures. The approach focused on three perennial grass species: Andropogon gayanus cv. Planaltina (andropogon grass), Panicum maximum cv. Massai (massai grass), and Brachiaria brizantha cv. BRS Piatã (piata grass). Calibration was conducted using four artificial DNA mixtures with known dry matter proportions: mixture 1 = 33

The study aimed to investigate the impact of dietary supplementation with green propolis crude extract on juvenile tilapia's growth and intestinal microbiota. The experiment was conducted in raceway tanks with a volume of 19m3, comprising two treatments with three replicates each. Fish were assigned to either a control diet or a diet supplemented with 0.67

Selecting animals to reduce their environmental impact is important for implementing sustainable livestock production systems. Identifying genes influencing water consumption and general activity in grazing beef cattle can aid in selecting efficient animals. This work aimed to verify the differential gene expression (DE) and dispersion (DD) profiles associated with water consumption frequency (WCF) and general activity (GA) in grazing Nelore and F1 (Nelore × Angus) cattle. Behavioral data were collected from 36 to 33 Nelore and F1 animals, respectively, for 12 h daily over four days. For the RNA sequencing, ten animals (five with higher frequency and five with lower frequency) were selected for WCF and GA in each breed. The functional and enrichment analyses revealed that the genes found in the WCF animals were associated with glucose metabolism (LOC520336 and GCNT2), kidney physiology (ATP6V0A4), the immune system (CD96 and KLRD1), adaptive capacity, fat deposition (THBS1), and blood pressure maintenance (CDCA7). The genes influencing GA were associated with adaptation to environmental temperature and challenging conditions (SLC16A6, STOM, CLTA and IFNAR2). More pronounced changes and functional enrichments was observed in Nelore cattle, particularly for WCF. F1 cattle showed more differential dispersion genes related to general activity, suggesting variability in gene expression might be more relevant for this trait in the crossbred animals. In conclusion, the genes identified in this study were associated with several important traits related to the adaptive capacity of animals. These genes can elucidate and help select animals that are more adapted to challenging environments and reduce their environmental impact, leading to a more sustainable livestock production system.

The objective of this study was to investigate if dietary supplementation with vitamins C and E, simultaneously, can neutralize, or reduce, the effects of acute and chronic heat stress on the expression of key genes in the skeletal muscle of chickens. A total of 384 one-day-old male broiler chickens were housed in thermoneutral chambers up to 28 days of age. They were then reallocated in groups of four per cage, in three environmentally controlled chambers: two thermoneutral (22.5 and 22.6 degrees C) and one for heat stress (32 degrees C). Half the chickens in each chamber were fed a diet supplemented with vitamins C (257 to 288 mg/kg) and E (93 to 109 mg/kg). In the thermoneutral chambers, half of the chickens were pair-fed to heat stressed chickens. Real-time quantitative PCR (RT-qPCR) was performed to access gene expression in breast muscle samples after 21 h (acute) or 16 days (chronic) under heat stress. Vitamin supplementation, under acute heat stress, contributed to downregulate avUCP, MSTN, and ACLY expressions. Vitamin supplementation reduced avUCP expression with pair-feeding compared to thermoneutral controls. Chickens did not show any changes in HSP70 expression level from both heat stress experiments, probably because they have adapted quickly. Under chronic heat stress, vitamin supplementation upregulated MSTN expression, possibly to reduce muscle mass hypertrophy and, consequently, maintain homeothermy. ACLY was not differentially expressed under chronic stress. In conclusion, exposing chickens to heat stress in the grower finishing phases impacted gene expression, but not all the effects were due to the high temperature per se. Diet supplementation with vitamins C and E under stress conditions (acute heat stress or feed restriction) produced the unexpected effect of decreasing avUCP expression, possibly a metabolic adaptation to regulate the antioxidative function. Diet supplementation with vitamins C and E may assist the body in coping with the effects of heat stress on metabolism by regulating the expression of MSTN and ACLY, genes involved in the maintenance of homeothermy.

Introduction:Understanding regulatory mechanisms like epigenetics can help improve beef production, carcass, and meat quality. Epigenetic states are dynamic and shaped by the environment, but due to limited studies and costly detection methods, alternative approaches are needed. Objective:Our aim was to identify candidate regulators linked to production, carcass and beef quality traits by describing genes putatively regulated by epigenetic mechanisms in the muscle of Nelore cattle. Methods:We in-silico identified discordantly regulated genes (DRGs) with the TRIAGE method and rank product analysis, using gene expression. We investigated the DRGs for being known bovine transcription factors (TFs) or co-factors (TcoFs) and tested the association of SNPs harbouring the DRGs with the traits. Using public muscle ATAC-Seq and ChIP-Seq data, we found that the associated SNPs were harboured in open chromatin sections of the genome and/or on histone modification regions. Results:We identified 51 DRGs across the traits and provided evidence of their regulatory status. 26 DRGs are known bovine TFs. A SNP upstream of the PITX2 DRG was associated with conjugated linoleic acid (CLA), 35 SNPs within or around the BTNL9 DRG were associated with backfat thickness (BFT) and 13 of the DRGs showed a regulatory impact over at least one trait. Discussion:The correlations identified among DRGs, differentially expressed genes and traits showed intricate relationships with various TFs and TcoFs, revealing the putative relationships of these elements with the traits. The LBX1 and HOXC10 genes are candidates with evidence to be regulators of the traits, while also being subjected to epigenetic regulation.

Diet influences ruminal methane emissions by modulating the composition and activity of the rumen microbiome. However, how diet shapes the functional capacity of the rumen microbiome in Nelore cattle (Bos indicus), a key tropical beef breed, remains unclear. This study used metatranscriptomics to investigate how dietary supplementation with agro-industrial by-products affects the active rumen microbiome and its association with residual methane emissions. Rumen samples from 50 Nelore cattle fed either a conventional or by-product-based diet revealed that the active microbiome was dominated by bacteria (88.4% ± 3.16%) and archaea (11.6% ± 3.16%), with no significant taxonomic differences between diets. Despite this, functional profiling identified genes from 193 pathways and 3,512 gene families, with distinct metabolic signatures between diets. Specifically, six pathways and 87 gene families were unique to the conventional diet, while seven pathways and 210 gene families were unique to the by-product diet. The associations between gene families enriched under each diet with residual methane emission revealed that the expression of two gene families exhibited negative correlations, while five were positively correlated with methane emission under conventional diet. In the by-product diet, we identified five gene families positively associated with methane emissions and 14 negatively associated. These results demonstrate that diet alters rumen microbial functions with methane mitigation potential, without affecting taxonomic composition. IMPORTANCE:Understanding how diet modulates the functional activity of the rumen microbiome is essential for developing strategies to mitigate methane emissions in cattle. This study provides novel insights into how feeding agro-industrial by-products to Nelore cattle (Bos indicus), a key tropical beef breed, reshapes the functional profile of the rumen microbiome. Although no taxonomic shifts were detected, animals fed the by-product diet exhibited a greater number of microbial functions associated with lower methane production potential. These findings suggest that diet-driven modulation of microbial metabolism could contribute to strategies aimed at reducing methane emissions. Moreover, the use of by-products supports circular economy principles, enhancing the sustainability and economic resilience of tropical livestock systems. This work emphasizes the importance of examining the active microbiome through RNA rather than solely profiling taxonomic composition without considering microbial activity. It also contributes to unveiling microbial functions to support future methane mitigation and sustainable feeding strategies.

The minor effects of many SNP interactions often determine complex traits. This interaction, known as epistasis, represents a non-additive genetic effect in which the influence of one variant depends on the presence of others. In this study, we tested for epistatic effects on the residual feed intake (RFI) and residual methane emission (RME) traits of Nelore cattle. Additionally, we evaluated the impact of these interactions in other omics layers (i.e., microorganism profiles in the rumen content and feces and mRNA and miRNA expression in the rumen wall). The genomic interaction modules identified 14 and 10 significant SNP-SNP modules associated with RME and RFI traits, respectively. The majority of these SNPs were located in intronic and intergenic regions. The top pathways and processes associated with the SNP-SNP modules were identified, with several pathways related to the immune system and actin cytoskeleton organization. Furthermore, many other omics data were correlated with these SNP-SNP modules. Our findings suggest that the immune response and cilium organization may play important roles in feed efficiency. These insights not only provide novel candidates for enhancing these traits through microbiota composition and transcriptional regulation but also underscore the power of network analysis in uncovering new functional interactions. This research provides new insights and highlights candidate features for improving cattle feed efficiency and methane emissions.

In the production environment of chickens, exposure to unpredictable light patterns is a common painless stressor, widely used to influence growth rate and egg production efficiency. The pineal gland, a key regulator of circadian rhythms through melatonin secretion, responds to environmental light cues, and its function is modulated by epigenetic mechanisms. In this study, we investigated how the pineal gland methylome and transcriptome (including micro-RNAs) interact to respond to a rearing exposure to unpredictable illumination patterns, with a particular focus on sex differences. We conducted an integrative multi-omic analysis-including methylomic (MeDIP-seq), transcriptomic (RNA-seq), and miRNA expression profiling-on the pineal gland of Hy-Line White chickens (n = 34, 18 females, 16 males) exposed to either a standard 12:12 light-dark cycle (control) or a randomized, unpredictable light schedule from Days 3 to 24 post-hatch. Our findings reveal that unpredictable light exposure alters the pineal gland methylome and transcriptome in a sex-specific manner. However, while transcriptomic differences between sexes increased due to the stress, methylomic differences decreased, particularly on the Z chromosome. These changes were driven by females (the heterogametic sex in birds), which became more male-like in their pineal methylome after exposure to the illumination stress, leading to reduced epigenetic sexual dimorphism while maintaining differences at the gene expression level. Further, we implemented a fixed sex effect model as a biological proof of concept, identifying a network of 12 key core genes interacting with 102 other genes, all linked to circadian regulation and stress adaptation. This network of genes comprises a core regulatory framework for circadian response. Additionally, tissue-specific expression analysis and cell-type specific expression analysis revealed enrichment in brain regions critical for circadian function, including neuronal populations involved in circadian regulation and the hypothalamic-pituitary-thyroid axis. Together, these findings provide strong evidence of sex-specific epigenetic transcriptomic responses of the pineal gland upon illumination stress and offer valuable insights into the interplay of different omic levels in relation to circadian response.

The coronavirus disease 2019 (COVID-19) pandemic has triggered a global health crisis, with over 700 million confirmed cases and at least 7 million deaths reported by early 2024. Children are less vulnerable to severe SARS-CoV-2 infection than adults and typically experience milder respiratory symptoms. However, a rare but significant complication, known as multisystem inflammatory syndrome in children (MIS-C), can develop weeks after infection, characterized by a spectrum of inflammatory symptoms. This study employed whole-exome sequencing and over-representation analysis to identify genetic variants of potential clinical significance related to MIS-C or severe COVID-19 in a group of children with acute respiratory distress syndrome (ARDS), all of whom were unvaccinated for COVID-19. We observed the enrichment of potentially pathogenic genetic variants in genes related to carbohydrate metabolism, particularly glycogen breakdown, in severe COVID-19 pediatric patients, and in genes related to cholesterol and lipoprotein metabolism in MIS-C patients. These findings offer insights into the genetic underpinnings of MIS-C and severe COVID-19, suggesting potential genes and biological pathways for further research.

Since 2021, the emergence of variants of concern (VOC) has led Brazil to experience record numbers of in COVID-19 cases and deaths. The expanded spread of the SARS-CoV-2 combined with a low vaccination rate has contributed to the emergence of new mutations that may enhance viral fitness, leading to the persistence of the disease. Due to limitations in the real-time genomic monitoring of new variants in some Brazilian states, we aimed to investigate whether genomic surveillance, coupled with epidemiological data and SARS-CoV-2 variants spatiotemporal spread in a smaller region, can reflect the pandemic progression at a national level. Our findings revealed three SARS-CoV-2 variant replacements from 2021 to early 2022, corresponding to the introduction and increase in the frequency of Gamma, Delta, and Omicron variants, as indicated by peaks of the Effective Reproductive Number (Reff). These distinct clade replacements triggered two waves of COVID-19 cases, influenced by the increasing vaccine uptake over time. Our results indicated that the effectiveness of vaccination in preventing new cases during the Delta and Omicron circulations was six and eleven times higher, respectively, than during the period when Gamma was predominant, and it was highly efficient in reducing the number of deaths. Furthermore, we demonstrated that genomic monitoring at a local level can reflect the national trends in the spread and evolution of SARS-CoV-2.

Nelore is a Bos indicus beef breed that is well-adapted to tropical environments and constitutes most of the world’s largest commercial cattle herd: the Brazilian bovine herd. Despite its significance, microbial genome recovery from ruminant microbiomes has largely excluded representatives from Brazilian Nelore cattle. To address this gap, this study presents a comprehensive dataset of microbial genomes recovered from the rumen and feces of 52 Brazilian Nelore bulls. A total of 1,526 non-redundant metagenome-assembled genomes (MAGs) were recovered from their gastrointestinal tract, with 497 ruminal and 486 fecal classified as high-quality. Phylogenetic analysis revealed that the bacterial MAGs fall into 12 phyla, with Firmicutes and Bacteroidota being the most predominant, while all archaeal MAGs belong to the genus Methanobrevibacter. The exploration of these microbial genomes will provide valuable insights into the metabolic potential and functional roles of individual microorganisms within host-microbiome interactions, contributing to a better understanding of the microbiome’s roles in bovine performance.

Intramuscular fat (IMF) and backfat thickness (BFT) are critical economic traits impacting meat quality. However, the genetic variants controlling these traits need to be better understood. To advance knowledge in this area, we integrated RNA-seq and single nucleotide polymorphisms (SNPs) identified in genomic and transcriptomic data to generate a linkage disequilibrium filtered panel of 553,581 variants. Expression quantitative trait loci (eQTL) analysis revealed 36,916 cis-eQTLs and 14,408 trans-eQTLs. Association analysis resulted in three eQTLs associated with BFT and 24 with IMF. Functional enrichment analysis of genes regulated by these 27 eQTLs revealed noteworthy pathways that can play a fundamental role in lipid metabolism and fat deposition, such as immune response, cytoskeleton remodeling, iron transport, and phospholipid metabolism. We next used ATAC-Seq assay to identify and overlap eQTL and open chromatin regions. Six eQTLs were in regulatory regions, four in predicted insulators and possible CCCTC-binding factor DNA binding sites, one in an active enhancer region, and the last in a low signal region. Our results provided novel insights into the transcriptional regulation of IMF and BFT, unraveling putative regulatory variants.

Background Understanding the molecular underpinnings of phenotypic variations is critical for enhancing poultry breeding programs. The Brazilian broiler (TT) and laying hen (CC) lines exhibit striking differences in body weight, growth potential, and muscle mass. Our work aimed to compare the global transcriptome of wing and pectoral tissues during the early development (days 2.5 to 3.5) of these chicken lines, unveiling disparities in gene expression and regulation. Results Different and bona-fide transcriptomic profiles were identified for the compared lines. A similar number of up- and downregulated differentially expressed genes (DEGs) were identified, considering the broiler line as a reference. Upregulated DEGs displayed an enrichment of protease-encoding genes, whereas downregulated DEGs exhibited a prevalence of receptors and ligands. Gene Ontology analysis revealed that upregulated DEGs were mainly associated with hormone response, mitotic cell cycle, and different metabolic and biosynthetic processes. In contrast, downregulated DEGs were primarily linked to communication, signal transduction, cell differentiation, and nervous system development. Regulatory networks were constructed for the mitotic cell cycle and cell differentiation biological processes, as their contrasting roles may impact the development of distinct postnatal traits. Within the mitotic cell cycle network, key upregulated DEGs included CCND1 and HSP90 , with central regulators being NF-κB subunits ( RELA and REL ) and NFATC2 . The cell differentiation network comprises numerous DEGs encoding transcription factors (e.g., HOX genes), receptors, ligands, and histones, while the main regulatory hubs are CREB , AR and epigenetic modifiers. Clustering analyses highlighted PIK3CD as a central player within the differentiation network. Conclusions Our study revealed distinct developmental transcriptomes between Brazilian broiler and layer lines. The gene expression profile of broiler embryos seems to favour increased cell proliferation and delayed differentiation, which may contribute to the subsequent enlargement of pectoral tissues during foetal and postnatal development. Our findings pave the way for future functional studies and improvement of targeted traits of economic interest in poultry.

The coronavirus disease 2019 (COVID-19) pandemic has triggered a global health crisis, with over 700 million confirmed cases and at least 7 million deaths reported by early 2024. Children are less vulnerable to severe SARS-CoV-2 infection than adults and typically experience milder respiratory symptoms. However, a rare but significant complication, known as multisystem inflammatory syndrome in children (MIS-C), can develop weeks after infection, characterized by a spectrum of inflammatory symptoms. This study employed whole-exome sequencing and over-representation analysis to identify distinct pathogenic genetic variants related to MIS-C or severe COVID-19 in a group of children with acute respiratory distress syndrome (ARDS), all of whom were unvaccinated for COVID-19. We observed an enrichment of pathogenic variants in genes related to carbohydrate metabolism, particularly glycogen breakdown, in severe COVID-19 pediatric patients, and in genes related to cholesterol and lipoprotein metabolism in MIS-C patients. These findings offer insights into the genetic underpinnings of MIS-C and severe COVID-19, suggesting potential genes and biological pathways for further research.

Feed cost represents a major economic determinant within cattle production, amounting to an estimated 75% of the total variable costs. Consequently, comprehensive approaches such as optimizing feed utilization through alternative feed sources, alongside the selection of feed-efficient animals, are of great significance. Here, we investigate the effect of two diets, traditional corn-grain fed and alternative by-product based, on 14 phenotypes related to feed, methane emission and production efficiency and on multi-tissue transcriptomics data from liver, muscle, and rumen wall, derived from 52 Nellore bulls, 26 on each diet. To this end, diets were contrasted at the level of phenotype, gene expression, and gene-phenotype network connectivity. As regards the phenotypic level, at a P value < 0.05, significant differences were found in favour of the alternative diet for average daily weight gain at finishing, dry matter intake at finishing, methane emission, carcass yield and subcutaneous fat thickness at the rib-eye muscle area. In terms of the transcriptional level of the 14,776 genes expressed across the examined tissues, we found 487, 484, and 499 genes differentially expressed due to diet in liver, muscle, and rumen, respectively (P value < 0.01). To explore differentially connected phenotypes across both diet-based networks, we focused on the phenotypes with the largest change in average number of connections within diets and tissues, namely methane emission and carcass yield, highlighting, in particular, gene expression changes involving SREBF2, and revealing the largest differential connectivity in rumen and muscle, respectively. Similarly, from examination of differentially connected genes across diets, the top-ranked most differentially connected regulators within each tissue were MEOX1, PTTG1, and BASP1 in liver, muscle, and rumen, respectively. Changes in gene co-expression patterns suggest activation or suppression of specific biological processes and pathways in response to dietary interventions, consequently impacting the phenotype. The identification of genes that respond differently to diets and their associated phenotypic effects serves as a crucial stepping stone for further investigations, aiming to build upon our discoveries. Ultimately, such advancements hold the promise of improving animal welfare, productivity, and sustainability in livestock farming.

Wood serves crucial functions in plants, yet our understanding of the mechanisms governing the composition, arrangement, and dimensions of its cells remains limited. The abrupt transition from nonlianescent to lianescent xylem in lianas represents an excellent model to address the underlying mechanisms, although consistent triggering factors for this process remain uncertain. In this study we examined how physical support attachment impacts the development of lianescent xylem in Bignonia magnifica (Bignoniaceae), employing a comprehensive approach integrating detailed anatomical analysis with gene expression profiling of cambium and differentiating xylem. Our findings demonstrate that attachment to physical supports triggers the formation of lianescent xylem, leading to increased vessel size, broader vessel distribution, reduced fibre content, and higher potential specific water conductivity than nonlianescent xylem. These shifts in wood anatomy coincide with the downregulation of genes associated with cell division and cell wall biosynthesis, and the upregulation of transcription factors, defense/cell death, and hormone-responsive genes in the lianescent xylem. Our findings provide insights into the regulation of xylem differentiation, driven by response to environmental stimuli. Additionally, they shed light on the mechanisms underlying the adaptation of lianas to climbing.