Researchers systematically assessed four key variables affecting transformation: culture medium, A. rhizogenes strain, seedling age and explant type. The selected protocol used strain K599 for infection and Hoagland-moistened vermiculite as the substrate. This combination produced successful hairy-root induction from all three explant types examined. The study did not describe the exact culture conditions, replicate numbers or statistical uncertainty in the supplied abstract, so the performance of the protocol across additional genotypes and experimental environments cannot be determined from this evidence.

Among nine developmental regulators tested, FsMP co-transformation increased leaf transformation efficiency to 95%. The abstract does not report efficiency values for the other eight regulators, meaning that 95% can be described as the reported performance of FsMP co-transformation but not as a demonstrated maximum across the full comparison. The broader objective was to reduce the low efficiency and long culture cycles associated with conventional A. tumefaciens-mediated transformation, which has hindered genomic and molecular-breeding studies in F. suspensa.

The authors characterized the resulting hairy-root system as a rapid, economical alternative to conventional tissue culture and proposed it as a platform for validating gene function and supporting molecular breeding in F. suspensa and other woody species. These are stated research conclusions rather than demonstrated field or breeding outcomes: the supplied evidence comes from an abstract and does not address genetic stability, regeneration of transformed shoots, field performance or long-term expression. The article was also identified as an early peer-reviewed version subject to further editorial changes.

Subject of Research: Optimization of hairy-root transformation and gene editing in Forsythia suspensa

Article Title: Establishment of a high-efficiency hairy root transformation system for Forsythia suspensa and enhancement of transformation efficiency by developmental regulators

Article References: Li, Q., Shao, Q., Wang, D., Zhang, N., Qiao, Y., & Song, Y. (2026). Establishment of a high-efficiency hairy root transformation system for Forsythia suspensa and enhancement of transformation efficiency by developmental regulators. BMC Plant Biology. https://doi.org/10.1186/s12870-026-09996-4

Image Credits: AI Generated

DOI: 10.1186/s12870-026-09996-4

Keywords: Forsythia suspensa, hairy-root transformation, Agrobacterium rhizogenes, FsMP, CRISPR/Cas9, RUBY reporter, leaf transformation, gene editing, woody plants, molecular breeding, Establishment, high-efficiency

The research team assembled five cultivars of Salvia miltiorrhiza for head-to-head comparison: Danza No.1, Danza No.2, Jidan No.4, Danza No.5 and an Anguo accession. These materials were provided and field-managed with support from the Hebei Academy of Agriculture and Forestry Sciences, giving the comparison an agronomic grounding that purely greenhouse-based studies often lack. Rather than ranking the varieties on a single marker compound, the researchers built what they describe as a quality-efficiency evaluation framework, integrating phenotypic and anatomical traits, quantitative determination of the major active components, preliminary comparative data on enzyme inhibition, and non-targeted metabolite profiling. The approach reflects a growing consensus in medicinal plant science that quality is multidimensional, and that a germplasm judged only on one molecule may hide weaknesses or strengths invisible to a narrower lens.

On the chemical side, the team deployed UHPLC coupled to quadrupole-Orbitrap tandem mass spectrometry, a high-resolution platform capable of detecting and annotating trace constituents in complex plant extracts. This analysis annotated 95 constituents across the samples, providing an untargeted chemical fingerprint for each cultivar that went well beyond the nine standard compounds quantified in the targeted portion of the work. Those nine reference standards spanned both branches of the plant’s chemical repertoire: protocatechuic aldehyde, caffeic acid, rosmarinic acid, salvianolic acid B and salvianolic acid A on the phenolic acid side, and dihydrotanshinone I, tanshinone I, tanshinone IIA and cryptotanshinone among the tanshinones. Calibration curves, precision, repeatability and stability validation underpinned the quantification, ensuring that differences between cultivars reflected biology rather than analytical noise.

When the metabolomic profiles were compared using principal component analysis and orthogonal partial least squares discriminant analysis, one cultivar separated decisively from the pack. Jidan No.4, abbreviated JD4 in the study, exhibited the most distinct metabolomic profile of the five varieties and delivered the best overall performance in the integrated quality-efficiency evaluation. The statistical models were validated with permutation testing and quality-control procedures, and pairwise comparisons between Anguo and each of the other cultivars identified differentially expressed metabolites with rigorous thresholds based on variable importance in projection and fold change. In plain terms, JD4 did not merely edge out its competitors on a single metric; its entire chemical signature, and its combined performance across anatomy, chemistry and preliminary bioactivity, marked it as a high-performing candidate germplasm.

The preliminary bioactivity screen added an intriguing functional dimension. The researchers tested extracts from the different germplasms for their ability to inhibit cholesterol esterase and pancreatic lipase, two digestive enzymes with obvious relevance to metabolic health and to the traditional use of the plant in cardiovascular contexts. The supplementary data include IC50 curves for both enzymes and comparisons of inhibitory effects across the five germplasms, positioning this enzyme panel as a first-pass functional readout to complement the chemical quantification. The authors are careful to frame these as preliminary comparative data rather than definitive pharmacological conclusions, but the integration of such assays into a germplasm evaluation pipeline is itself notable, bridging the gap between compositional analysis and biological plausibility.

Having established that JD4 was chemically distinctive, the team turned to the transcriptome to ask what genetic programs might underlie that distinction. Comparative RNA sequencing of root tissue identified 2,851 differentially expressed genes in JD4 relative to the Anguo accession. When these genes were subjected to enrichment analysis, three functional categories rose to the top: plant hormone signal transduction, MAPK signaling, and plant-pathogen interaction pathways. This pattern is biologically telling. Specialized metabolites such as tanshinones are not housekeeping molecules; they are defensive chemicals whose production is often wired into the same signaling circuits that plants use to perceive attack and stress. The fact that the highest-performing cultivar shows heightened expression in defense and hormone pathways suggests that its chemical superiority may be a byproduct of an especially active defensive metabolism.

The most technically ambitious step was the direct integration of the two data layers. By correlating the abundance of differentially expressed metabolites with the expression levels of differentially expressed genes, the researchers uncovered significant associations between tanshinone-related compounds and defense- or hormone-responsive genes. Two relationships stood out. Cryptotanshinone was negatively associated with CML, a calcium signaling component, hinting that calcium-mediated signaling may act as a brake on this particular tanshinone. Tanshinone IIA, by contrast, showed positive associations with two transcription factors, PIF4 and ABF, which sit squarely within light-responsive and abscisic acid-related regulatory networks respectively. These correlations do not prove causation, but they generate concrete, testable hypotheses about the regulatory architecture governing tanshinone accumulation in high-quality roots.

The study also connected chemistry back to physical structure. Among the supplementary materials is a regression analysis, selected by Bayesian information criterion, linking microscopic anatomical features of the medicinal material with the contents of representative active compounds. Such structure-chemistry relationships matter in practice because root anatomy is what processors and pharmacists see, and a validated statistical bridge between visible traits and invisible metabolite content could eventually allow rapid, non-destructive quality screening. Combined with the detailed microscopic feature counts and the quantitative contents of the nine standard compounds in all five varieties, the dataset offers one of the more complete portraits of quality formation in this species published to date.

The authors validated key findings at the molecular level with quantitative real-time PCR, confirming the differential expression patterns of selected genes identified in the RNA sequencing. Sequencing quality was tightly controlled, with the supplementary tables reporting clean reads, GC content, Q30 values and mapping rates to the reference genome for the root libraries of both Anguo and JD4. This attention to analytical rigor, from mass spectrometry method validation through OPLS-DA model testing to PCR confirmation, strengthens confidence that the cultivar differences are real and reproducible rather than artifacts of batch effects or platform drift.

The practical implications reach from the field to the breeding program. By highlighting JD4 as a promising candidate germplasm, the study gives growers and breeders in Hebei and beyond a data-backed starting point, while the catalog of associated metabolites, genes and pathways provides molecular targets for future functional validation and marker-assisted selection. The authors are appropriately measured, noting that JD4 warrants further field and functional validation under the present experimental conditions before its status is considered settled. Still, the multi-dimensional framework they demonstrate, fusing anatomy, targeted and untargeted chemistry, preliminary bioactivity and dual-omics analysis, offers a template that could be applied to other medicinal plants whose quality has historically been judged by tradition rather than data. For a species whose roots have been prized for roughly two millennia, the path to consistently high-quality medicine may now run through correlation matrices and signaling pathways rather than folklore alone.

Subject of Research: Integrated transcriptome and metabolome analysis of quality formation in Salvia miltiorrhiza germplasms

Article Title: Integration of transcriptome and metabolome analyses reveals the mechanism of high-quality formation in Salvia miltiorrhiza

Article References: Li, W., Zhang, H., Fan, X., Jiang, T., Wen, C., Du, Y., & Tian, X. (2026). Integration of transcriptome and metabolome analyses reveals the mechanism of high-quality formation in Salvia miltiorrhiza. BMC Plant Biology. https://doi.org/10.1186/s12870-026-09924-6

Image Credits: AI Generated

DOI: 10.1186/s12870-026-09924-6

Keywords: Salvia miltiorrhiza, tanshinones, salvianolic acids, metabolomics, transcriptomics, germplasm evaluation, molecular breeding, plant hormone signaling, MAPK signaling, defense response, UHPLC-MS/MS, medicinal plants

The motivation is straightforward. Nearly all natural rubber in commerce comes from the rubber tree, Hevea brasiliensis, a tropical species whose cultivation is geographically concentrated and increasingly vulnerable to disease and land-use pressure. TKS offers a temperate alternative: its roots produce rubber particles suspended in latex, and its taproots also store inulin, a high-added-value fructan used in food and pharmaceutical applications. Yet the tissue-specific regulation of natural rubber biosynthesis in TKS has remained poorly resolved. Which tissues actually run the biosynthetic program, which genes are switched on there, and which proteins carry out the work are questions that a single omics layer cannot fully answer.

To close that gap, the team profiled four TKS samples in parallel: main roots, lateral roots, main leaves, and latex. The scale of the survey was substantial. Across the four tissues, the researchers identified 31,569 genes and 2,782 proteins, and then asked which of these showed pronounced tissue specificity. The answer was revealing. Genes and proteins specific to latex were mainly enriched in terpenoid backbone biosynthesis, the metabolic highway that supplies the isoprenoid building blocks from which rubber polymer is assembled. That enrichment pattern places the latex compartment, not the bulk root tissue, at the center of the rubber-building enterprise.

The analytical machinery behind this conclusion is worth unpacking. Transcriptomics measures the messenger RNA output of every gene, telling researchers which genetic instructions are being read in each tissue. Proteomics measures the actual protein complement, telling them which molecular machines are physically present. Because mRNA abundance and protein abundance do not always track each other, integrating the two layers is the only rigorous way to distinguish genes that are merely transcribed from genes whose products are actively deployed. The team used a nine-quadrant analysis to cross-reference the two datasets, plotting transcripts and proteins together and isolating candidates whose expression correlated positively across tissues.

That cross-referencing paid off. The nine-quadrant analysis highlighted 19 natural rubber biosynthesis-related candidates with positively correlated expression, and among them three names recurred consistently across tissue comparisons: SRPP5, SRPP9, and REF1. These are not random picks. SRPP proteins, short for small rubber particle proteins, and REF proteins, short for rubber elongation factors, are the canonical structural components of rubber particles in latex. They are thought to stabilize the rubber polymer as it is synthesized and to govern particle architecture, making their consistent presence across tissue comparisons a strong signal that the same core machinery operates wherever rubber is made in the plant.

Going further, the researchers built co-expression subnetworks centered on natural rubber biosynthesis, derived from latex-associated modules. In these networks, genes that rise and fall together across tissues are treated as functionally connected, and the most connected nodes are interpreted as hubs of coordinated activity. The subnetworks highlighted SRPP4, SRPP5, SRPP6, SRPP9, REF1, CPTL1, and ACAT4 as highly connected nodes. CPTL1 belongs to the cis-prenyltransferase-like family, enzymes directly involved in polymerizing isopentenyl units into the rubber backbone, while ACAT4 is an acetyl-CoA acetyltransferase that feeds the mevalonate pathway upstream of isoprenoid production. The network picture therefore spans the entire biosynthetic pipeline, from precursor supply to polymer assembly and particle stabilization.

Perhaps the most intriguing layer of the study concerns regulation rather than structure. Superimposed on the biosynthetic machinery, the team identified transcription factors of the bHLH, C3H, and TCP families, together with proteins annotated as HP, LEA, and R40G3, linked to multiple natural rubber biosynthesis-related genes and proteins. Transcription factors are the switches that turn gene programs on and off, and the fact that three distinct families converge on the rubber module suggests an additional coordinated regulatory layer that the structural genes alone do not capture. LEA proteins, typically associated with dehydration tolerance, and the other associated proteins hint that rubber accumulation may be entwined with the latex cell’s stress physiology, a connection that deserves targeted follow-up.

The researchers did not rely on the omics data alone. They validated selected natural rubber biosynthesis genes by quantitative real-time PCR, an independent technique that measures transcript abundance with high sensitivity. The qPCR results corroborated the robustness of the transcriptomic dataset, confirming that the tissue-specific expression patterns were not artifacts of sequencing depth or normalization. This kind of orthogonal validation is what separates a credible candidate list from a speculative one, and it strengthens the case that the 19 candidates and the seven network hubs are genuine leads rather than statistical noise.

The practical implications reach into molecular breeding. Rubber yield in TKS is a quantitative trait shaped by many genes, and breeders have historically relied on phenotypic selection, a slow process constrained by the plant’s life cycle and the difficulty of measuring rubber content non-destructively. A prioritized list of candidate regulators changes the calculus. Markers linked to SRPP and REF variants, or to the bHLH, C3H, and TCP transcription factors identified here, could accelerate selection for high-rubber-yielding lines. The same candidates could also inform genome editing or transgenic approaches aimed at rerouting carbon flux toward rubber synthesis, potentially raising yields in a crop that can be grown on temperate farmland rather than tropical plantations.

The study also leaves open questions that the field will now pursue. How the latex-centered regulatory module is switched on during root development, whether the LEA and HP proteins reflect a stress-coupled dimension of rubber accumulation, and how the transcription factor layer communicates with the biosynthetic enzymes are all unresolved. What the current work establishes is the molecular framework: a latex-centered module comprising SRPP and REF proteins and associated transcription factors plays a pivotal role in coordinating natural rubber biosynthesis in TKS. For a world searching for secure, sustainable rubber supply, that framework is a map, and the candidates it highlights are the signposts for the next generation of rubber crops.

Subject of Research: Plant Molecular Biology

Article Title: Tissue-specific transcriptome and proteome analyses of Taraxacum kok-saghyz reveal key genes for natural rubber biosynthesis

Article References: Wang, J., Ma, J., Yuan, B., He, L., Nie, Q., Deng, T., Wang, S., Qin, W., & Wang, X. (2026). Tissue-specific transcriptome and proteome analyses of Taraxacum kok-saghyz reveal key genes for natural rubber biosynthesis. BMC Plant Biology. https://doi.org/10.1186/s12870-026-09968-8

Image Credits: AI Generated

DOI: 10.1186/s12870-026-09968-8

Keywords: Taraxacum kok-saghyz, natural rubber biosynthesis, transcriptomics, proteomics, transcription factors, latex, SRPP, REF, molecular breeding, BMC Plant Biology, Tissue-specific, transcriptome

Researchers at Inner Mongolia Agricultural University, working with colleagues from the Agricultural and Animal Husbandry Technology Extension Center of Inner Mongolia Autonomous Region, set out to answer a deceptively simple question: why do some strains of H. erinaceus grow faster and more vigorously than others? The answer matters commercially, because extensive prior work has shown that the eventual yield of mature fruiting bodies is tightly linked to the state of the mycelium that precedes them. Faster mycelial growth reflects better environmental adaptability, more efficient absorption and conversion of nutrients from the culture medium, stronger metabolic activity, and greater overall vitality. In practical cultivation, H. erinaceus is notoriously demanding, with stringent environmental requirements that make fruiting induction difficult and yields relatively low, while its mycelia are comparatively easy to propagate. Understanding the genes behind mycelial vigor therefore opens a direct route to better cultivation and breeding.

The team selected two commercially relevant strains, named Jing3 and 911, which differ visibly in colony characteristics and growth vigor. Both were grown on potato dextrose agar at 25 degrees Celsius in the dark, and sampling began once mycelial growth initiated after three days of incubation. Mycelial samples were harvested at seven and fourteen days post-germination, snap-frozen in liquid nitrogen, and stored at minus 80 degrees Celsius until analysis. Each strain at each stage included three biological replicates, producing twelve sequenced samples in total. Before any sequencing, the researchers carefully quantified the physiological differences: they measured germination time, time to full plate colonization, mycelial growth rate using the cross method with a vernier caliper, biomass yield, mycelial density, and colony morphology. They also assayed core biochemical indicators, including protein content, soluble sugars, proline, and cellulase activity, using commercial assay kits.

The physiological data told a clear story. Both strains germinated after the same three days, but Jing3 displayed consistently greater growth vigor and denser mycelia than 911. Across both time points, both strains showed significant increases in growth rate, biomass, protein, soluble sugar, proline, and cellulase activity, and at every measured parameter Jing3 significantly outperformed 911. These measurements established that the two strains genuinely represent fast- and slower-growing phenotypes, providing the biological contrast needed for the transcriptomic comparison that followed.

For the molecular analysis, total RNA was extracted from all twelve samples and sequenced on the Illumina platform. The workflow was technically rigorous: messenger RNA was enriched using oligo(dT)-conjugated magnetic beads, fragmented, converted into first- and second-strand cDNA, purified with AMPure XP beads, then subjected to end repair, A-tailing, adapter ligation, size selection, and PCR amplification before high-throughput sequencing. The sequencing generated 78.53 gigabases of raw reads, of which 77.09 gigabases of high-quality clean reads were retained after filtering. Quality metrics were excellent, with Q20 scores around 98.78 percent, Q30 around 96.53 percent, and GC content near 56.87 percent. Clean reads were aligned to the latest H. erinaceus reference genome using HISAT2, transcript assembly was performed with StringTie, and expression levels were quantified with the RSEM package using FPKM as the metric.

Quality control confirmed the dataset’s reliability. Pearson correlation coefficients among biological replicates ranged from 0.89 to 1.00, indicating high reproducibility, and principal component analysis showed that the three replicates of each condition clustered tightly together while the two genotypes formed distinct clusters at each growth stage. Differential expression analysis using DESeq2, with thresholds of a p-value below 0.05, an absolute fold change of at least 2, and a false discovery rate below 0.05, identified a total of 3,257 differentially expressed genes across the comparisons. Strikingly, upregulated genes significantly outnumbered downregulated ones, indicating that mycelial growth is accompanied by a predominantly activated transcriptional program rather than a shutdown of existing processes.

The comparison structure revealed an intriguing asymmetry between the strains. In the within-strain comparisons from day 7 to day 14, the 911 strain underwent 1,505 differentially expressed genes, with 808 upregulated and 697 downregulated, while Jing3 showed 1,203, with 729 upregulated and 474 downregulated. This suggests that the slower-growing 911 strain actually experiences more pronounced transcriptional changes as it grows. Between strains, only 67 genes differed at day 7, but 482 differed at day 14, indicating that the regulatory divergence between genotypes widens and becomes more complex as mycelial development proceeds. Overall, 574 genes were expressed specifically in 911 and 350 in Jing3, while 676 genes were co-expressed in both, implying substantial transcriptional overlap in the machinery regulating growth rate. Only six genes were co-expressed across both time points, and 142 genes were exclusive to the fourteen-day phase, underscoring that late-stage mycelial maturation involves a far more intricate regulatory network than early growth.

Functional annotation pointed to the biochemical engines driving this growth. Gene Ontology enrichment analysis showed that the differentially expressed genes were primarily associated with oxidoreductase activity, the enzymatic function that mediates redox reactions in energy metabolism and secondary metabolite biosynthesis. In strain 911, 26.01 percent of differentially expressed genes fell into small molecule metabolic process, 15.88 percent into oxidoreductase activity, and 15.20 percent into small molecule biosynthetic process. In Jing3, the top terms were oxidoreductase activity at 17.51 percent, ribosome biogenesis at 16.59 percent, and nucleolus at 15.67 percent. The ribosome enrichment makes biological sense: ribosomes are the molecular machinery of protein synthesis, and their upregulation aligns with the rapid growth and nutrient accumulation characteristic of mycelium maturation, a pattern previously observed in Flammulina velutipes and Auricularia. Ribosomes also participate in DNA repair, organismal development, and cell division, all processes that intensify during active hyphal extension.

Kyoto Encyclopedia of Genes and Genomes pathway analysis sharpened the picture further, concentrating the differentially expressed genes in amino acid metabolism pathways, including arginine and proline metabolism, phenylalanine metabolism, and tryptophan metabolism. These pathways are pivotal for supplying essential nitrogen sources, regulating cellular osmotic balance, and synthesizing bioactive molecules that support proliferation. The individual gene patterns were revealing. Of the 22 differentially expressed genes in arginine and proline metabolism, most were significantly upregulated in both strains, with more upregulated genes in 911 than in Jing3. The six genes in phenylalanine metabolism split evenly, three upregulated and three downregulated in each strain. Among the 11 genes in tryptophan metabolism, two genes, august03889 and august09942, were upregulated and highly expressed specifically in Jing3. The functional logic is compelling: proline reduces reactive oxygen species in edible fungi and inhibits programmed cell death, arginine regulates growth and development through its metabolites and associated enzymes, phenylalanine-derived phenolic compounds such as gallic acid scavenge excess intracellular reactive oxygen, and tryptophan exhibits antioxidant activity through its hydroxyl and amino functional groups. Together, these findings suggest that the mycelium actively manages the oxidative stress generated during its own growth, converting amino acid metabolism into a protective and proliferative advantage.

To validate the sequencing results, the team performed quantitative real-time PCR on ten randomly selected differentially expressed genes, using the 18S rRNA gene as an internal reference and the standard 2-delta-delta-Ct method for relative quantification. The RT-qPCR data showed high consistency with the RNA-seq measurements, confirming the credibility of the transcriptomic dataset for candidate gene screening. The authors are candid about the study’s limitations: only two genotypes and two growth stages were examined, which cannot fully resolve the complete transcriptional dynamics of mycelial maturation, and functional inferences rest mainly on transcriptomic data and homologous annotation rather than direct experimental evidence. Future work, they note, will expand the number of strains and developmental stages, apply co-expression network analysis, and integrate multi-omics with molecular functional verification. Even so, the dataset, publicly deposited under NCBI accession PRJNA1321699, provides a robust theoretical foundation for optimizing stable large-scale cultivation of H. erinaceus and for molecular-assisted breeding aimed at improving agronomic traits. For a mushroom whose market value rests on both nutrition and medicine, knowing which genes switch on as the mycelium spreads may prove to be the first step toward growing it faster, more reliably, and at scale.

Subject of Research: Transcriptomic mechanisms regulating mycelial growth in Hericium erinaceus

Article Title: Transcriptomic analysis of Hericium erinaceus mycelia at distinct growth stages: insights into molecular mechanisms underlying mycelial proliferation

Article References: Zong, H., Duan, Y., Li, X., & Bao, H. (2026). Transcriptomic analysis of Hericium erinaceus mycelia at distinct growth stages: insights into molecular mechanisms underlying mycelial proliferation. Frontiers in Fungal Biology, 7, Article 1778644. https://doi.org/10.3389/ffunb.2026.1778644

Image Credits: AI Generated

DOI: 10.3389/ffunb.2026.1778644

Keywords: Hericium erinaceus, lion's mane mushroom, mycelial growth, transcriptomics, RNA sequencing, differentially expressed genes, amino acid metabolism, oxidoreductase activity, edible fungi, molecular breeding, fungal physiology, cultivation optimization

ADAMTS15 belongs to the ADAMTS family of secreted enzymes, which carry a distinctive thrombospondin type 1 motif and cut through components of the extracellular matrix, the scaffold that surrounds cells. The enzyme participates in tissue remodeling through the hydrolysis of hyaluronic acid, a major structural molecule in that matrix. Earlier work in mice showed that ADAMTS15 is expressed during myogenesis, the process by which muscle fibers form, and that it helps regulate myoblast fusion, the step in which immature muscle cells merge into multinucleated fibers. But in goats, the mechanisms governing when and where the gene is switched on remained largely unknown. The new study set out to fill that gap by characterizing the gene’s expression profile, mapping its regulatory elements, and testing whether variants in those elements associate with growth traits in a local Chinese breed.

The team worked with Anhui White goats, a breed raised in Anhui Province, and examined ADAMTS15 expression across a range of tissues as well as in the longissimus dorsi, the large back muscle that runs along the spine and is a primary cut in meat production. Their measurements confirmed that the gene is expressed in goat muscle and revealed a progressive decline during development, with embryonic muscle tissues showing significantly higher expression than postnatal stages. This pattern mirrors what has been observed in mice and reinforces the idea that ADAMTS15 plays a role in the early construction of muscle tissue, when myoblasts are actively fusing and fibers are being assembled, rather than in the maintenance of mature muscle.

With the expression pattern established, the researchers turned to the central technical challenge of the study: locating the sequences that drive the gene’s transcription. They used dual-luciferase reporter assays, a technique in which candidate DNA fragments are cloned upstream of a luciferase gene and introduced into cells; if a fragment contains promoter or enhancer activity, the luciferase enzyme lights up, providing a quantitative readout of regulatory strength. By testing a series of overlapping fragments, they mapped the promoter activity region to a stretch between 678 and 385 base pairs upstream of the transcription start site. The enhancer screen identified five active fragments, labeled E2, E4, E6, E7, and E8, each capable of boosting transcription when tested in the reporter system.

A closer look at the mapped promoter region revealed that it overlaps with a CpG island, a cluster of cytosine-guanine dinucleotides that often serves as a landing zone for methylation, a chemical modification that can silence genes. DNA methylation analysis of this island produced an unexpected result: all 14 CpG sites within it remained unmethylated in longissimus dorsi muscle from 75-day-old fetuses, 1-day-old newborns, and 10-month-old adult goats. The complete absence of methylation across three developmental stages suggests that this CpG island functions as a stable, open regulatory element rather than a dynamic methylation-controlled switch, and it hints that other mechanisms, such as transcription factor binding, may be the primary drivers of the gene’s developmental expression pattern.

The researchers then screened for genetic variants across the promoter, the enhancer regions, and the gene itself using Sanger sequencing, the gold-standard method for reading DNA sequence directly. They identified single nucleotide polymorphisms, or SNPs, positions where a single DNA letter differs between individuals, and tested whether these variants associate with six growth traits measured in the goat population, including body weight, body length, chest circumference, and cannon circumference, the girth of the lower leg bone that reflects skeletal development. The association analysis produced a set of significant hits that span the gene’s entire regulatory architecture.

In the promoter region, two variants stood out. Promoter-SNP2 was significantly associated with body weight, while Promoter-SNP5 showed a significant association with cannon circumference. In the enhancer regions, Enhancer-SNP1 was significantly associated with both chest circumference and cannon circumference. Within the gene itself, SNP2 was significantly associated with body weight, and SNP3 showed significant associations with all six growth traits, making it the broadest hit in the study. These results indicate that variation in the sequences that control ADAMTS15 expression, as well as variation in the gene’s coding and genic regions, contributes to measurable differences in how goats grow.

To move beyond correlation, the team performed functional analysis of the two most compelling regulatory variants. They found that Promoter-SNP2 genotypes significantly affected promoter activity in the reporter assay, meaning that the different DNA letters at this position change how strongly the promoter drives transcription. Similarly, Enhancer-SNP1 genotypes significantly affected enhancer activity, altering the strength of the enhancer fragment in which it sits. This combination of statistical association with growth traits and direct functional effects on regulatory activity provides strong evidence that these variants are not merely linked to growth differences but actively participate in producing them, by tuning the expression level of ADAMTS15 during muscle development.

The study offers a detailed foundation for understanding the transcriptional regulatory mechanisms of ADAMTS15 in goat muscle development, and it demonstrates a workflow that other researchers can apply to any gene of interest in livestock: characterize expression, map regulatory elements with reporter assays, examine methylation status, screen for variants with Sanger sequencing, and test both associations with traits and functional effects on regulatory activity. The identified variants may serve as potential molecular markers for goat molecular breeding, allowing breeders to select animals carrying favorable alleles at these positions to improve growth performance. For a breed like the Anhui White goat, which is valued as a local genetic resource, such markers could accelerate genetic improvement while preserving the breed’s distinctive characteristics.

Beyond the practical implications for breeding, the work adds to a growing body of evidence that the ADAMTS family of enzymes, long studied for their roles in tissue remodeling and matrix biology, also participates in the genetic architecture of growth in livestock. The finding that a gene involved in myoblast fusion in mice shows a developmentally regulated expression pattern and trait-associated variants in goats suggests that the underlying biology of muscle formation is conserved across species, even as the specific regulatory sequences evolve. As genome editing and precision breeding technologies mature, understanding the regulatory elements and variants that govern genes like ADAMTS15 will become increasingly important for translating basic biology into improved animal health and productivity.

Subject of Research: Genomics

Article Title: Identification of regulatory elements and association analysis of genetic variants with growth traits of goat ADAMTS15 gene

Article References: Zhang, S., Yan, N., Peng, J., Chen, J., Zhu, L., Li, S., Ji, K., Xu, H., Huang, D., & Ling, Y. (2026). Identification of regulatory elements and association analysis of genetic variants with growth traits of goat ADAMTS15 gene. BMC Genomics. https://doi.org/10.1186/s12864-026-13467-3

Image Credits: AI Generated

DOI: 10.1186/s12864-026-13467-3

Keywords: goat, ADAMTS15, gene regulation, promoter, enhancer, growth traits, genetic variation, molecular breeding, BMC Genomics, Identification, regulatory, elements

Telomere-to-telomere assemblies represent the current gold standard of genome sequencing. Rather than leaving gaps where repetitive DNA confounds reconstruction, a T2T genome traces each chromosome from one physical end to the other, capturing centromeres, telomeres and other tandemly repeated regions that earlier draft assemblies simply omitted. For licorice, this mattered because the genus had long lacked near-complete genome assemblies, limiting both the study of how bioactive metabolites such as glycyrrhizic acid, liquiritin, licochalcone A and glabridin are synthesized and the investigation of how these plants endure extreme aridity, salinity and heat. The new G. uralensis T2T assembly resolves all eight chromosomes with complete telomeres and fully characterized centromeres, providing a reference against which other licorice genomes and populations can be aligned with confidence.

A particularly striking technical achievement of the assembly is its characterization of centromeric DNA. The researchers identified two centromeric tandem repeat monomers, designated Cen60 and Cen307, with the latter appearing to be specific to chromosome 4 of G. uralensis. To confirm that these repeat sequences genuinely mark the centromeres rather than being assembly artifacts, the team performed oligo-fluorescence in situ hybridization (FISH) experiments using eight chromosome-specific painting probes together with probes for Cen60 and Cen307. The cytological results matched the sequence-based predictions, anchoring the computational assembly to physical chromosome structure. In parallel with the T2T effort, the consortium produced chromosome-level assemblies for all three pharmacopoeia species, enabling comparative analyses of synteny across the genus and a Circos-plot visualization of structural relationships among the genomes.

With high-quality references in hand, the team turned to natural diversity. They generated re-sequencing data for 188 wild licorice accessions collected across Xinjiang, a region in northwestern China where vast desert and semi-desert habitats harbor major wild licorice populations. From these data, the researchers constructed a large-scale genomic variation map that catalogues millions of single-nucleotide polymorphisms, insertions and deletions across the genus. Population-genomic analyses revealed a clear pattern of geographic and genetic differentiation shaped by the Tianshan Mountains, a massive range that divides Xinjiang into distinct ecological zones. G. uralensis was found mainly in the northern Xinjiang region (XJN), G. inflata dominates the hotter, more arid southern region (XJS), and G. glabra occurs across the whole region, a distribution that hints at different adaptive histories among the three species.

The population dataset allowed the researchers to move beyond simple cataloguing. They delineated core germplasm groups for G. uralensis and G. inflata, providing breeders with a structured picture of the diversity available for future crossing and selection programs. The analyses also detected extensive introgression between species, meaning that the genomes of wild licorice plants carry DNA segments exchanged through interspecies hybridization events. Such gene flow is scientifically significant because it can transfer adaptive alleles across species boundaries, and it is practically important for breeding programs that may seek to combine the chemical richness of one species with the environmental robustness of another.

To connect genome variation to the traits that make licorice valuable, the team performed selective-sweep scans across the genomes. These scans look for regions where genetic diversity has been unusually reduced, a signature that natural or artificial selection has favored certain haplotypes. In the licorice genomes, dozens of genes under selection were identified, many of them annotated with roles in triterpenoid and flavonoid biosynthesis, the two metabolic pathways that generate glycyrrhizic acid, liquiritin and the chalcone-type flavonoid licochalcone A. This observation suggests that the medicinal chemistry of licorice has been shaped by evolutionary pressures on its wild populations, and it gave the researchers a focused set of candidate genes for downstream validation.

The pivotal step was to integrate multiple layers of functional information. The team combined tissue-specific transcriptome data, RNA-sequencing experiments under abiotic stress treatments, correlation analyses between gene expression and climate variables at collection sites, and a genome-wide association study (GWAS) linking genetic variants to metabolite content. Converging evidence from all four approaches pointed to a single gene, 4CL5, as a major determinant of licochalcone A accumulation. This gene encodes a 4-coumarate-CoA ligase, an enzyme family that channels precursors into phenylpropanoid and flavonoid branches of plant metabolism. Licochalcone A is one of the most intensively studied licorice constituents, noted for anti-inflammatory and other pharmacological activities, so identifying a genetic control point for its production carries both basic-science and applied significance.

Molecular experiments then established the regulatory mechanism. Using yeast one-hybrid screening, dual-luciferase reporter assays and electrophoretic mobility shift assays (EMSA), the researchers demonstrated that a transcription factor named GiPHL1 physically binds a specific DNA motif, the P1BS cis-element, located in the promoter of the Gi4CL5 gene in G. inflata. The prefix Gi denotes the G. inflata orthologs. Binding of GiPHL1 to the P1BS element activates transcription of Gi4CL5, thereby enhancing flux into the pathway that produces licochalcone A. The GiPHL1-Gi4CL5 regulatory module, therefore, functions as a coordinated switch that promotes the biosynthesis of a medicinally important flavonoid.

What makes the discovery especially compelling is that this same module appears to serve two purposes at once. In addition to driving licochalcone A accumulation, the pathway activity it controls contributes to improved stress resistance in G. inflata, the species that thrives in the hot, arid habitats of southern Xinjiang. This dual function offers an elegant evolutionary explanation for why a compound of pharmaceutical interest would be maintained at high levels in wild plants: chalcone-type metabolites can participate in plant defense and stress mitigation, so selection for desert survival may have inadvertently enriched the chemical treasury that human medicine values. The finding thus links metabolite biosynthesis and environmental adaptation in a single genetic circuit, a connection that had long been suspected but not genetically resolved in licorice.

The practical implications of the work extend across several fronts. For molecular breeding, the candidate genes and molecular markers emerging from the selective-sweep, GWAS and regulatory analyses provide tools for precision selection, allowing breeders to develop licorice varieties with higher yields of glycyrrhizic acid, licochalcone A and other active compounds while also carrying alleles that confer stronger tolerance to drought and heat. For synthetic biology, the identification of specific biosynthetic and regulatory genes such as Gi4CL5 and GiPHL1 supplies components that could be deployed in engineered microbes or plant systems to produce licorice-derived substances without harvesting wild populations. The T2T and chromosome-scale reference genomes themselves will serve as foundational infrastructure for future genetics in the genus, much as complete reference genomes have transformed research in rice, maize and other crops. As demand for licorice continues in pharmaceuticals, food and industrial manufacturing, the new genomic resources offer a route toward sustainable utilization of a plant whose value has been appreciated for millennia but whose genes are only now coming into focus.

Subject of Research: Telomere-to-telomere genome assembly of medicinal licorice species and the genetics of metabolite biosynthesis and drought adaptation

Article Title: First telomere-to-telomere (T2T) licorice genome uncovers key genes for medicinal metabolite biosynthesis and desert stress adaptation

Article References: First telomere-to-telomere (T2T) licorice genome uncovers key genes for medicinal metabolite biosynthesis and desert stress adaptation. (n.d.). Original publication

Image Credits: AI Generated

DOI: Not provided

Keywords: licorice, Glycyrrhiza uralensis, telomere-to-telomere genome, T2T assembly, licoachalcone A, genome-wide association study, transcription factor, drought tolerance, flavonoid biosynthesis, molecular breeding, population genomics, Science China Life Sciences

The gene, named GmVQ32, belongs to a distinctive and still somewhat mysterious family of plant proteins defined by a short, highly conserved stretch of amino acids known as the VQ motif. VQ proteins have attracted growing attention in recent years because they frequently act as interaction partners for WRKY transcription factors, the master regulators that orchestrate plant responses to pathogens, drought, and a host of abiotic stresses. The research team, led by Qundi Li and Shuying Fan as co-first authors and corresponding authors Xiuxiang Zhang and Qibin Ma, had previously flagged GmVQ32 in transcriptomic screens as a gene whose activity surges when soybean roots encounter aluminium ions. What remained unknown was whether that surge was merely a molecular echo of stress or a functional component of the plant’s defense, and whether the gene’s remit extended beyond aluminium to the phosphorus starvation that so often accompanies it.

To answer those questions, the researchers first cloned GmVQ32 from soybean and subjected it to a battery of bioinformatic and molecular analyses. Sequence comparisons placed the protein in subgroup V of the plant VQ family, a classification that hints at shared functional properties with other members of that clade. Scrutiny of the region upstream of the gene, its promoter, revealed a rich collection of predicted cis-acting elements, the short DNA sequences that serve as docking sites for regulatory proteins. Notably, the promoter carried elements associated with responsiveness to the hormones abscisic acid and salicylic acid, as well as elements linked to a variety of stress responses. That regulatory architecture suggested GmVQ32 sits at a junction of multiple signaling pathways, poised to be switched on under several different kinds of environmental duress rather than a single narrow trigger.

Expression profiling added further texture to the picture. The gene turned out to be constitutively expressed across a range of soybean organs, meaning it is transcribed at baseline levels throughout the plant rather than confined to a single tissue, but its transcript abundance peaked in flowers. More telling was the response to stress treatments. When the researchers exposed soybean plants to aluminium chloride or to phosphorus-starved conditions, quantitative reverse-transcription PCR showed that GmVQ32 expression climbed significantly under both treatments. In other words, the gene does not merely respond to aluminium; it also hears the alarm of phosphate deprivation, consistent with the idea that in acidic soils these two stresses are managed by overlapping regulatory circuits. Subcellular localization experiments confirmed that the GmVQ32 protein accumulates in the nucleus, the compartment where transcription factors do their work, and yeast assays demonstrated that the protein possesses genuine transcriptional activation activity, meaning it can switch on reporter genes in a yeast system rather than simply binding DNA inertly.

Perhaps the most consequential molecular finding came from yeast two-hybrid assays, which revealed that GmVQ32 physically interacts with GmWRKY21, a soybean member of the WRKY transcription factor family. This interaction is significant because it places GmVQ32 squarely within the well-characterized WRKY regulatory network. VQ proteins are widely thought to modulate the activity of their WRKY partners, sometimes enhancing and sometimes restraining their effects on target genes. The physical association between GmVQ32 and GmWRKY21 therefore provides a plausible mechanistic bridge: a stress-activated VQ protein that enters the nucleus and tunes the output of a WRKY regulator controlling downstream defense genes. While the full architecture of that network in soybean remains to be mapped, the interaction gives breeders and biotechnologists a concrete entry point into the pathway.

To test whether GmVQ32 actually confers tolerance rather than merely responding to stress, the team engineered Arabidopsis thaliana, the standard laboratory workhorse of plant genetics, to overexpress the soybean gene. The results under aluminium stress were striking. Compared with wild-type plants, the transgenic lines showed increased relative root elongation, a key indicator of aluminium tolerance because Al³⁺ rapidly arrests root growth. They also accumulated less aluminium in their tissues, suggesting the gene helps keep the toxic ion out of the plant or limits its internal effects. Biochemical markers told a consistent story: proline content, a sign of osmoprotective stress responses, rose in the transgenic plants, while malondialdehyde levels, a standard readout of lipid peroxidation and cellular membrane damage, fell. Together these measurements indicate that GmVQ32 overexpression reduces the oxidative and structural damage that aluminium inflicts on root cells.

The benefits extended to phosphorus deficiency as well. Under low-phosphorus treatments, the GmVQ32 transgenic Arabidopsis lines built greater biomass, developed more extensive root systems, and maintained higher phosphorus content in their tissues than wild-type controls. A larger, more vigorous root architecture is a classic adaptive response to phosphate starvation, since phosphorus is poorly mobile in soil and plants must effectively forage for it with their roots. The fact that a single soybean gene could enhance this foraging response in a heterologous species suggests the underlying regulatory logic is conserved across plants, raising the possibility that GmVQ32 or its counterparts in other crops could be deployed broadly.

The researchers then probed which downstream genes GmVQ32 might be controlling. Under aluminium toxicity, the transgenic Arabidopsis showed significantly upregulated expression of several canonical aluminium stress marker genes, including AtALS3, AtALMT1, AtMATE, and AtSTOP1. These genes are central to the well-studied aluminium tolerance machinery of Arabidopsis: AtSTOP1 is a transcription factor that activates the aluminum response, AtALMT1 encodes a transporter that releases malate, an organic acid that chelates and detoxifies Al³⁺ in the rhizosphere, AtMATE encodes a citrate transporter with a similar detoxifying role, and AtALS3 is implicated in internal aluminium tolerance and redistribution. Their coordinated upregulation in GmVQ32 overexpression lines indicates that the soybean protein plugs into and amplifies an ancient, conserved aluminum-defense program. Similarly, under phosphorus starvation, the transgenic plants showed increased expression of phosphate-responsive marker genes including AtMGD2, AtPAP10, AtPHO1, and AtPHR1, genes involved in phospholipid remodeling, secretion of acid phosphatases, and the master phosphate signaling cascade. Functional analyses reinforced the story at the level of the crop itself: overexpressing GmVQ32 in soybean hairy roots and in Arabidopsis significantly reduced Al³⁺ accumulation in plant roots.

Taken together, the study makes a case that GmVQ32 is not a peripheral player but a genuine enhancer of plant tolerance to two of the most widespread soil constraints on crop productivity, likely acting through the modulation of stress-responsive transcriptional networks that bridge aluminium detoxification and phosphate acquisition. The work, supported by China’s National Key Research and Development Program and the National Natural Science Foundation of China, arrives at a moment when agricultural science is urgently searching for genetic levers to make staple crops more resilient on marginal land. Much remains to be done before GmVQ32 reaches the field: the precise relationship between GmVQ32 and GmWRKY21 needs to be dissected in soybean itself, the gene’s effects on agronomic traits and yield in elite soybean backgrounds must be validated, and any trade-offs under unstressed conditions need to be assessed. But as a candidate gene for molecular breeding or genome editing aimed at acidic, aluminium-laden, phosphorus-poor soils, GmVQ32 now stands out as one of the more compelling leads to emerge from the VQ family, offering the tantalizing prospect of a single genetic switch that helps roots survive poison and hunger at the same time.

Subject of Research: The role of the soybean VQ motif gene GmVQ32 in enhancing plant tolerance to aluminium toxicity and low-phosphorus stress

Article Title: GmVQ32 enhances tolerance to aluminium toxicity and low-phosphorus stress in Arabidopsis

Article References: Li, Q., Fan, S., Zhu, X., Chen, S., Lin, H., Lian, T., Cheng, Y., Cai, Z., Zhang, X., & Ma, Q. (2026). GmVQ32 enhances tolerance to aluminium toxicity and low-phosphorus stress in Arabidopsis. BMC Plant Biology. https://doi.org/10.1186/s12870-026-10148-x

Image Credits: AI Generated

DOI: 10.1186/s12870-026-10148-x

Keywords: soybean, GmVQ32, aluminium toxicity, phosphorus deficiency, VQ motif, WRKY transcription factors, Arabidopsis thaliana, acidic soils, transcriptional regulation, plant stress tolerance, root architecture, molecular breeding

Telomere-to-telomere, or T2T, assembly represents the gold standard of modern genomics. Conventional genome assemblies leave behind hundreds or even thousands of unresolved stretches known as gaps, typically in regions crammed with repetitive DNA such as centromeres, ribosomal RNA gene clusters and other satellite-rich zones. These gaps matter. They hide genes, obscure structural variation and make it impossible to say exactly how many chromosomes a species truly carries. A T2T assembly eliminates those holes entirely, reading each chromosome as one continuous thread from the telomere at one end to the telomere at the other. Achieving this for a plant genome is notoriously difficult, since plant genomes are often loaded with repetitive transposable elements that confound sequencing algorithms.

The team overcame the challenge by combining three complementary sequencing strategies. Pacific Biosciences HiFi reads provided highly accurate long stretches of DNA, Oxford Nanopore ultra-long reads extended those stretches across the most stubborn repetitive regions, and Hi-C, a technique that captures the physical contacts between chromosomes inside the cell nucleus, was used to order and orient the sequences into full-length chromosomes. The final assembly spans roughly 890.50 megabase pairs and achieves a scaffold N50 of 44.26 megabases, meaning half of the assembled sequence resides in chromosomes longer than 44 million bases. The entire genome was organized into exactly 20 gap-free chromosomes, each capped by telomeres, with 40 telomeres and 20 putative centromere regions identified in total.

One of the most consequential results is the definitive resolution of the chromosome number of I. cornuta. Botanists have debated the basic chromosome number of this species for years, with conflicting counts circulating in the cytological literature. The new gap-free assembly shows unambiguously that the species carries 20 pairs of chromosomes, a diploid complement written as 2n = 2x = 40. Crucially, the team did not rely on sequencing data alone. An independent karyotype analysis of root-tip cells, in which chromosomes are stained and counted directly under the microscope, confirmed the genomic count. Agreement between the molecular assembly and classical cytogenetics settles a long-standing controversy and provides a firm foundation for evolutionary comparisons across the Aquifoliaceae family.

Genome quality was assessed with the metrics that the assembly community takes most seriously. The annotation, recovered using RNA sequencing data, predicted 35,437 protein-coding genes. Benchmarking with BUSCO, a test that searches for a set of universally conserved single-copy genes, returned a completeness score of 98.33 percent, indicating that almost the entire expected gene repertoire is present. The base-level accuracy of the assembly, expressed as a quality value or QV, reached 48.97, which corresponds to an error rate of roughly one mistake in every 79,000 bases. These figures place the Chinese holly assembly among the most accurate plant genomes published to date and demonstrate that the integration of HiFi, ultra-long and Hi-C data can deliver reference-grade sequences even for species with no prior genomic resources.

With the reference in hand, the researchers turned to evolutionary history. Comparative genomics against related plant species revealed two whole-genome duplication events in the ancestry of I. cornuta, ancient episodes in which the entire genetic complement was doubled and subsequently pared down through gene loss and divergence. Whole-genome duplications are a major engine of plant evolution, because duplicate genes are free to accumulate mutations and take on new functions. The analysis also uncovered lineage-specific expansions of gene families, with a pronounced enrichment in pathways governing secondary metabolism, the biochemical arsenal plants use to synthesize defensive compounds, pigments and medicinal molecules.

These expanded gene families are particularly intriguing given what the Chinese holly is known for. The species thrives under stresses that would defeat many ornamentals, and its tissues contain bioactive compounds of pharmaceutical interest. The authors are careful, however, to frame these expansions as candidate gene sets that could potentially contribute to environmental adaptability. Genomic evidence of expansion does not by itself prove function. Verifying the biological roles of these genes will require transcriptomic profiling across stress conditions and direct functional assays, such as gene knockout or overexpression experiments, work that the T2T reference now makes dramatically easier to design and interpret.

The significance of the assembly extends well beyond a single species. Ilex is a large and ecologically diverse genus of more than 400 evergreen and deciduous trees and shrubs distributed across temperate and tropical regions, and it had never before had a gap-free reference genome of any kind. The I. cornuta assembly therefore serves as a genomic anchor for the entire genus, enabling researchers to map other holly species against a complete, contiguous blueprint, reconstruct chromosome evolution within the family, and pinpoint the genetic basis of traits ranging from sex determination, a famously thorny question in hollies, to fruit color and cold hardiness.

For breeders, the practical implications are immediate. Ornamental holly breeding has traditionally depended on slow phenotypic selection and conventional crossing, approaches that are poorly suited to traits controlled by many genes or by structural variants buried in repetitive DNA. A telomere-to-telomere reference changes that calculus. It allows genome-wide association studies, marker-assisted selection and eventually genome editing to be pursued with confidence that the underlying sequence is complete and correctly ordered. Genes involved in stress tolerance, secondary metabolite production and ornamental quality can now be located precisely, tracked in breeding populations and, in time, targeted directly.

The work also stands as a showcase of how far genome science has traveled. Little more than a decade ago, completing a plant chromosome end to end was deemed unreachable; today, a coordinated pipeline of three sequencing technologies can deliver a gap-free reference for a species whose genome had never been assembled before. The Chinese holly now joins the small but growing roster of plants with fully finished genomes, and the resource, deposited and openly described by the Nanjing-led team, is freely available to researchers worldwide. For a genus that decorates gardens, supports traditional medicine and endures some of the toughest growing conditions in its native range, the holly has finally been given a complete instruction manual, and scientists are only beginning to read it.

Subject of Research: Telomere-to-telomere gap-free genome assembly of the Chinese holly, Ilex cornuta

Article Title: Telomere-to-telomere, gap-free genome assembly of the Chinese holly, Ilex cornuta

Article References: Zhou, P., Xu, K., Gong, W., Li, F., Sun, H., Zhang, Q., & Zhang, M. (2026). Telomere-to-telomere, gap-free genome assembly of the Chinese holly, Ilex cornuta. BMC Plant Biology. https://doi.org/10.1186/s12870-026-10103-w

Image Credits: AI Generated

DOI: 10.1186/s12870-026-10103-w

Keywords: Ilex cornuta, Chinese holly, telomere-to-telomere, genome assembly, centromere, chromosome number, whole-genome duplication, comparative genomics, PacBio HiFi, Oxford Nanopore, Hi-C, molecular breeding

Adventitious roots are roots that arise from non-root tissues, such as stems or cut surfaces, rather than from the embryonic radicle. They are the biological foundation of vegetative propagation, the technique by which growers clone elite trees to preserve desirable traits like growth rate, timber quality or medicinal chemistry. When a cutting fails to form adventitious roots, it dies. For E. ulmoides, a species prized for the rubber-like gutta-percha in its leaves and bark and for eucommiol-containing compounds used in traditional medicine, the naturally low capacity for adventitious root development has long constrained breeding programs that depend on cloning superior individuals. Understanding the genetic switches that govern this process is therefore not an academic curiosity but a practical imperative.

The WOX family sits at the heart of that regulatory machinery. These transcription factors, defined by a conserved DNA-binding homeobox domain, orchestrate stem cell maintenance, embryo patterning and organ initiation across the plant kingdom. In the model plant Arabidopsis thaliana, the clade containing WOX11 and its close relative WOX12 has been implicated in the earliest steps of de novo root organogenesis, the program that converts differentiated cells into root primordia. Because transcription factors act as master regulators that can switch entire developmental modules on or off, they are attractive targets for molecular breeding: tweak one gene and an entire trait may follow.

Scouring the E. ulmoides genome, the team identified eleven EuWOX genes. Rather than stopping at a simple count, the researchers built a full portrait of the family. They reconstructed the phylogenetic tree that relates each EuWOX protein to its counterparts in other species, mapped the exon-intron architecture of each gene, and surveyed expression patterns across tissues. This systematic characterization matters because gene function in the WOX family is tightly tied to evolutionary lineage; knowing which clade a gene occupies offers a strong first hypothesis about what it does. The analysis placed EuWOX11 in the same branch as Arabidopsis WOX11 and WOX12 and as PtWOX12 from Populus trichocarpa, the black cottonwood whose genome serves as a reference for the willow family. High sequence homology within this clade suggested that EuWOX11 had retained the ancestral root-building function of its relatives.

Expression data reinforced that hypothesis. Among the eleven genes, EuWOX11 stood out for its high transcript levels in the roots of E. ulmoides seedlings, precisely the tissue and developmental stage where adventitious root programs are most active. In gene-function studies, a correlation between expression location and a suspected role is a critical piece of circumstantial evidence, but it is not proof. To move from correlation to causation, the team turned to heterologous overexpression, introducing the EuWOX11 gene into a host species and asking what changes when the gene is forced into overdrive.

The chosen host was Populus tomentosa cultivar Lumao 50, a variety of Chinese white poplar widely used in plantations and amenable to transformation. This choice was strategic. Populus is a woody genus, so any effect observed there is more likely to translate to other trees than results obtained in herbaceous models. Moreover, poplar’s own WOX genes are well studied, giving researchers a benchmark against which to judge the behavior of the introduced EuWOX11. The team generated transgenic lines carrying the EuWOX11 coding sequence under a strong promoter and compared their root development with that of untransformed wild-type plants under identical conditions.

The results were unambiguous. Overexpression lines produced a significantly higher number of adventitious roots than wild-type controls. The effect extended beyond root count: the engineered plants also showed increased root length and greater root biomass, indicating that EuWOX11 did not merely trigger more root primordia but supported fuller root development overall. Perhaps most strikingly, the enhanced root systems were accompanied by promoted vegetative growth, meaning the aerial parts of the plants grew better as well. That coupling makes biological sense, since a larger root system improves water and nutrient uptake, but it also raises the practical stakes, because a gene that simultaneously improves rooting and overall vigor is exactly the kind of target breeders dream about.

For clonal propagation, the implications are direct. Cuttings that root faster and more profusely survive at higher rates and reach transplantable size sooner, compressing the production cycle for clonal stock. If EuWOX11 or its native orthologs can be manipulated in E. ulmoides itself, whether through transgenic approaches or through marker-assisted selection of naturally superior alleles, nurseries could multiply elite medicinal trees far more efficiently. The authors frame the work as a dual contribution: a candidate target for molecular breeding aimed at improving propagation efficiency in woody plants, and a molecular entry point for dissecting how adventitious root formation is regulated in E. ulmoides, a species whose genome has only recently become accessible to this kind of analysis.

The study also illustrates a broader trend in plant biotechnology: the pipeline from genome mining to functional validation is becoming routine even for non-model trees. Systematic family identification, phylogenetic placement, expression profiling and heterologous functional testing together form a template that can be applied to other recalcitrant species, from fruit trees to timber species, where rooting failure limits commercial cloning. Each new family portrait adds to a growing comparative dataset that allows researchers to predict gene function across species boundaries with increasing confidence, shortening the path from discovery to application.

Open questions remain. The work was conducted in a heterologous system, so confirming EuWOX11’s role within E. ulmoides itself, mapping the downstream genes it controls, and clarifying how it interacts with the auxin signaling pathways known to drive root initiation are logical next steps. The published version is also an early-release, peer-reviewed accepted manuscript subject to final editorial updates. Still, the core result stands: a single transcription factor from a medicinal tree, dropped into poplar, rewired the host’s root-building program to produce more, longer and heavier roots. In a field where propagation bottlenecks cost growers years, that is a result worth rooting for.

Subject of Research: WOX transcription factor regulation of adventitious root formation in Eucommia ulmoides

Article Title: Identification of the WOX genes in Eucommia ulmoides and functional identification of EuWOX11 in adventitious root formation and plant growth

Article References: Zhang, X., Qu, P., Zhu, Y., Zhao, D., & Wang, R. (2026). Identification of the WOX genes in Eucommia ulmoides and functional identification of EuWOX11 in adventitious root formation and plant growth. BMC Plant Biology. https://doi.org/10.1186/s12870-026-10156-x

Image Credits: AI Generated

DOI: 10.1186/s12870-026-10156-x

Keywords: Eucommia ulmoides, WOX gene family, EuWOX11, adventitious roots, transcription factors, clonal propagation, Populus tomentosa, heterologous overexpression, plant development, auxin, molecular breeding, woody plants

The significance of a telomere-to-telomere, or T2T, assembly is best understood by considering what earlier genome projects routinely missed. Standard short-read sequencing struggles with the highly repetitive DNA that forms centromeres, the structures that anchor chromosomes during cell division, and telomeres, the protective caps at chromosome ends. These regions are not genetic dead weight; as Yi Wang, first author of the study, explained, they often hold key information about genome stability and phenotypic variation. The previous assembly of C. gladiata left centromeric and telomeric regions unresolved, which meant that any attempt to link DNA sequence to traits of agronomic importance was working from an incomplete blueprint. A T2T assembly was therefore essential, in the authors’ view, for functional genomics and breeding. With the complete sequence in hand, researchers can now ask precise questions about how genes are organized, how repeats shape chromosome behavior, and which genomic features underlie the seed chemistry that makes sword bean nutritionally interesting.

Building the assembly required a combination of technologies, each compensating for the weaknesses of the others. The team used Oxford Nanopore ultra-long reads, which can span repetitive DNA tracts that defeat shorter reads, together with Hi-C scaffolding, a method that uses the physical proximity of chromosomes in the nucleus to order and orient sequence contigs correctly. Multiple assembly strategies were applied and reconciled. The result is an eleven-chromosome genome containing all 22 telomeres and 11 centromeres, a complete chromosomal set for the species. Within the centromeres, the researchers found the characteristic architecture of tandemly repeated DNA, but with an instructive twist: a single repeat family, a 504-base-pair sequence designated TR504, dominates the centromeres of six chromosomes, while the remaining chromosomes carry distinct repeat families of their own. This mosaic of centromeric repeats offers a natural experiment in how centromere DNA evolves, and it provides markers that will help chromosome biologists track centromere identity across legume species.

Placing the new genome in an evolutionary framework revealed where sword bean sits on the legume family tree. Comparative genomics identified C. gladiata as a basal member of the tribe Phaseoleae, the group that also includes soybean and several other major crops. The analysis estimated that sword bean diverged from soybean approximately 45 million years ago, a deep split that predates much of the diversification within the tribe. The distribution of synonymous substitution rates, a standard measure known as Ks analysis, showed that C. gladiata shares an ancient whole-genome duplication with soybean, a doubling event inherited from a common ancestor. Crucially, however, sword bean did not undergo the additional, more recent genome duplication that occurred specifically in the soybean lineage. This makes the sword bean genome a valuable reference for reconstructing ancestral legume karyotypes, because it preserves a simpler genomic structure that has been scrambled and reduplicated in soybean. Researchers seeking to understand what the genome of the last common ancestor of the Phaseoleae looked like now have a cleaner template to work from.

The genome alone would have been a substantial contribution, but the team went further by asking how the genetic blueprint plays out during seed development. They sampled seeds at three stages: 40 days after flowering, designated S1 and representing early development; 60 days after flowering, designated S2 and representing the middle phase; and 80 days after flowering, designated S3 and representing maturity. Widely targeted metabolomics, a technique that quantifies hundreds to thousands of small molecules simultaneously, detected 2,723 metabolites across the samples, with flavonoids emerging as the most abundant chemical class. In parallel, transcriptomic profiling identified 14,016 differentially expressed genes across the three developmental stages, a strikingly large fraction of the genome’s coding capacity that shifts in activity as the seed matures. Together, the two datasets allowed the researchers to connect metabolic changes to the genes that drive them.

The integrated analysis revealed a clear metabolic phase transition during seed development, a kind of molecular switch that redirects the plant’s carbon economy. In the early stage, S1, the seed is a site of active starch and sucrose metabolism, branched-chain amino acid degradation, and flavonoid biosynthesis. At the center of this early program sits glucose-6-phosphate, or G6P, a hub metabolite that links sugar breakdown to downstream biosynthetic pathways. G6P showed a remarkably strong correlation, with a coefficient of 0.99, with the transcription factor CgKNAT7, suggesting that this regulatory protein plays a role in carbon allocation, deciding how the seed partitions its sugar resources among storage, structure, and defense chemistry. Twelve flavonoid metabolites, including the well-known compounds catechin and quercetin, accumulated at the early stage alongside the coordinated expression of structural genes in the flavonoid pathway, including CHS, F3H, DFR, LAR, and ANR. This tight coupling of metabolite accumulation and gene expression gives breeders a concrete set of targets if they wish to modulate flavonoid content in the seed.

By the middle and late stages, S2 and S3, the picture changed decisively. Carbon flux that had earlier fed starch and flavonoid production was redirected toward fatty acid accumulation, consistent with the seed’s shift toward building its oil reserves. Free fatty acids, including the oxygenated lipid species 13(S)-HODE and 9(S)-HODE, peaked at the mature stage, and their accumulation was consistent with the expression of genes involved in linoleic acid metabolism, notably CgLOX5 and CgMMS19. The transition from a sugar-and-flavonoid program to a lipid-accumulation program mirrors patterns documented in other oilseed crops, but seeing it mapped gene by gene in sword bean converts a general principle into an actionable roadmap. Genes whose expression tracks the lipid shift become candidates for manipulation, whether the goal is increasing oil yield, altering the fatty acid profile toward more unsaturated species, or stabilizing seed composition across environments.

Why does this matter beyond the laboratory? Underutilized legumes are increasingly discussed as assets in a food system facing climate stress and protein demand. Crops that fix their own nitrogen, tolerate marginal conditions, and deliver high-quality seed protein can diversify agriculture away from a narrow set of staple commodities. Sword bean fits that profile on paper, with its 26 to 30 percent seed protein and unsaturated-fatty-acid-rich oil, but paper is where it stayed as long as breeders lacked the genomic tools to work with it efficiently. A complete reference genome changes the calculus. It enables molecular marker development, accelerates the identification of genes controlling nutritional quality, and allows comparative genomics to transfer knowledge from well-studied legumes like soybean to this orphan crop. The candidate genes surfaced by the multi-omics analysis, from CgKNAT7 and the flavonoid pathway genes to the lipid metabolism genes CgLOX5 and CgMMS19, provide a starting catalog for that effort.

The study also signals a broader shift in plant genomics. T2T assemblies, once a tour de force reserved for a handful of model organisms, are becoming the expected standard for new crop genomes, and this project demonstrates why. Repetitive centromeric and telomeric regions, far from being ignorable filler, carry information about genome stability, chromosome evolution, and potentially phenotypic variation. Combined with time-resolved transcriptomics and metabolomics, a complete genome becomes a dynamic portrait of a developing organ rather than a static parts list. The authors have deposited the T2T assembly, transcriptome data, and metabolome data in public databases, making the resource available to the global research community. For C. gladiata, the release of a gap-free genome marks the moment a neglected legume joins the ranks of genetically tractable crops, and for legume biology more broadly, it supplies a basal Phaseoleae reference that will sharpen evolutionary reconstructions across the entire tribe.

Subject of Research: Telomere-to-telomere genome assembly and multi-omics analysis of the legume Canavalia gladiata

Article Title: First telomere-to-telomere genome of Canavalia gladiata released: Multi-omics analysis uncovers candidate genes for nutritional composition

Article References: First telomere-to-telomere genome of Canavalia gladiata released: Multi-omics analysis uncovers candidate genes for nutritional composition. (n.d.). Original publication

Image Credits: AI Generated

DOI: Not provided

Keywords: Canavalia gladiata, sword bean, T2T genome, genomics, transcriptomics, metabolomics, seed development, legumes, flavonoids, fatty acids, molecular breeding, Phaseoleae