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OBJECTIVES Average treatment effects from randomized trials do not reflect the heterogeneity of an individual's response to treatment. This study evaluates the appropriate proportions of patients for coronary artery bypass grafting, or percutaneous intervention based on the predicted/observed ratio of 10-year all-cause mortality in the SYNTAX population. METHODS The study included 1800 randomized patients and 1275 patients in the nested percutaneous (n  = 198) or surgical (n  = 1077) registries. The primary end point was 10-year all-cause mortality. The SYNTAX score II-2020 was validated internally in the randomized cohort and externally in the registry cohort. Proportions of patients with survival benefits from coronary artery bypass grafting or percutaneous intervention were determined using SYNTAX score II-2020. RESULTS Ten-year mortality was 23.8% for coronary artery bypass grafting, 28.6% for percutaneous intervention in the randomized cohort, 27.6% for coronary artery bypass grafting and 55.4% for percutaneous intervention in the registries. In the coronary artery bypass grafting registry, the SYNTAX score II-2020 predicted 10-year mortality with helpful calibration and discrimination (C-index: 0.70, intercept: 0.00, slope: 0.76). The proportion of patients deriving a predicted survival benefit from coronary artery bypass grafting over percutaneous intervention was 82.4% (2143/2602) and 17.7% (459/2602) for the entire SYNTAX trial population, translating into a 4.7 to 1 appropriate ratio of treatment allocation to coronary artery bypass grafting and percutaneous intervention. CONCLUSIONS Choosing a revascularization modality should depend on an individual's long-term prognosis rather than average treatment effects. Additionally, patients should be informed about their predicted prognosis. Trial registration Registered on clinicaltrial.gov SYNTAXES NCT03417050 (https://clinicaltrials.gov/ct2/show/NCT03417050) SYNTAX NCT00114972 (https://www.clinicaltrials.gov/ct2/show/NCT00114972) [ABSTRACT FROM AUTHOR]

Abstract Background To adapt to constantly changing environments, ancient gymnosperms have coevolved with diverse endophytic fungi that are essential for the fitness and adaptability of the plant host. However, the effect of sex on plant-endophyte interactions in response to environmental stressors remains unknown. RNA-seq integrated with ITS analysis was applied to reveal the potential mechanisms underlying the sex-specific responses of Taxus mairei to ultraviolet (UV)-B radiation. Results Enrichment analysis suggested that sex influenced the expression of several genes related to the oxidation–reduction system, which might play potential roles in sex-mediated responses to UV-B radiations. ITS-seq analysis clarified the effects of UV-B radiation and sex on the composition of endophytic fungal communities. Sex influenced various secondary metabolic pathways, thereby providing chemicals for T. mairei host to produce attractants and/or inhibitors to filter microbial taxa. Analysis of fungal biomarkers suggested that UV-B radiation reduced the effect of sex on fungal communities. Moreover, Guignardia isolate #1 was purified to investigate the role of endophytic fungi in sex-mediated responses to UV-B radiation. Inoculation with spores produced by isolate #1 significantly altered various oxidation–reduction systems of the host by regulating the expression of APX2, GST7 NCED1, ZE1, CS1, and CM1. Conclusion These results revealed the roles of endophytic fungi in sex-mediated responses to UV-B radiation and provided novel insights into the sex-specific responses of Taxus trees to environmental stressors. Video Abstract

Abstract Background Taxol, derived from Taxus trees, is a valuable natural resource for the development of anticancer drugs. Endophytic fungi from Taxus trees are a promising alternative source of Taxol. However, the impact of plant-endophytic microbial interaction on the host’s Taxol biosynthesis is largely unknown. Results In the current study, the diversity of endophytic fungi in three different Taxus species was analyzed using Internal Transcribed Spacer sequencing. A total of 271 Operational Taxonomic Units (OTUs) were identified, grouping into 2 phyla, 8 classes, 16 orders, 19 families, and 19 genera. Alpha and beta diversity analysis indicated significant differences in endophytic fungal communities among the various Taxus trees. At the genus level, Alternaria and Davidiella were predominantly found in T. mairei and T. media, respectively. By utilizing a previously published dataset, a Pearson correlation analysis was conducted to predict the taxol biosynthesis-related fungal genera. Following screening, two isolates of Alternaria (L7 and M14) were obtained. Effect of inoculation with Alternaria isolates on the gene expression and metabolite accumulation of T. mairei was determined by transcriptomic and untargeted metabolomic studies. The co-inoculation assay suggests that the two Alternaria isolates may have a negative regulatory effect on taxol biosynthesis by influencing hormone signaling pathways. Conclusion Our findings will serve as a foundation for advancing the production and utilization of Taxus and will also aid in screening endophytic fungi related to taxol production.

Background: To adapt to constantly changing environments, ancient gymnosperms have coevolved with diverse endophytic fungi that are essential for the fitness and adaptability of the plant host. However, the effect of sex on plant-endophyte interactions in response to environmental stressors remains unknown. RNA-seq integrated with ITS analysis was applied to reveal the potential mechanisms underlying the sex-specific responses of Taxus mairei to ultraviolet (UV)-B radiation. Results: Enrichment analysis suggested that sex influenced the expression of several genes related to the oxidation–reduction system, which might play potential roles in sex-mediated responses to UV-B radiations. ITS-seq analysis clarified the effects of UV-B radiation and sex on the composition of endophytic fungal communities. Sex influenced various secondary metabolic pathways, thereby providing chemicals for T. mairei host to produce attractants and/or inhibitors to filter microbial taxa. Analysis of fungal biomarkers suggested that UV-B radiation reduced the effect of sex on fungal communities. Moreover, Guignardia isolate #1 was purified to investigate the role of endophytic fungi in sex-mediated responses to UV-B radiation. Inoculation with spores produced by isolate #1 significantly altered various oxidation–reduction systems of the host by regulating the expression of APX2, GST7 NCED1, ZE1, CS1, and CM1. Conclusion: These results revealed the roles of endophytic fungi in sex-mediated responses to UV-B radiation and provided novel insights into the sex-specific responses of Taxus trees to environmental stressors. 3pQjBcj-im_YZSujzFCGpb Video Abstract [ABSTRACT FROM AUTHOR]

A recent leading-edge study by Jiang et al. identified two enzymes that are responsible for key reactions in the biosynthesis of baccatin III. The authors successfully reconstructed the baccatin III synthesis pathway with a minimal number of synthetic enzymes in tobacco leaves, laying the foundation for industrial-scale sustainable production of the anticancer drug paclitaxel. [ABSTRACT FROM AUTHOR]

Taxus, a rare and protected genus predominantly distributed across the Northern Hemisphere's temperate regions, has garnered global attention due to its significant potential in medical research and pharmaceutical development, bolstered by advancements in cultivation techniques and medical technology. This review primarily focuses on the chemical constituents and pharmacological activities of Taxus, underscoring the progress and potential of these components in clinical applications. Recent studies have revealed that Taxus contains not only taxane active components but also flavonoids and polysaccharides with distinct activities. These compounds from Taxus exhibit potent antitumor, anti-inflammatory, immunomodulatory, antibacterial, and antidiabetic properties with evident mechanisms of action. Notably, the representative compound, paclitaxel, has demonstrated significant efficacy in treating various cancers, such as ovarian, breast, and lung cancer. This paper also reviews the basic situation of Taxus drug formulations, with extracts primarily administered orally and monomeric taxanes typically via injection, reflecting a mature development stage with ongoing research into oral formulations. Finally, this review summarizes the pharmacokinetic characteristics of crucial compounds in Taxus, including their absorption, distribution, metabolism, and excretion patterns in the human body. These pharmacokinetic profiles provide crucial guidance for evaluating the overall dosing regimen of Taxus and its components. The paper concludes with a forward-looking analysis of the potential applications of these compounds in disease treatment, envisioning their role in the future of medical and pharmaceutical advancements. [ABSTRACT FROM AUTHOR]

Background: Taxol, derived from Taxus trees, is a valuable natural resource for the development of anticancer drugs. Endophytic fungi from Taxus trees are a promising alternative source of Taxol. However, the impact of plant-endophytic microbial interaction on the host's Taxol biosynthesis is largely unknown. Results: In the current study, the diversity of endophytic fungi in three different Taxus species was analyzed using Internal Transcribed Spacer sequencing. A total of 271 Operational Taxonomic Units (OTUs) were identified, grouping into 2 phyla, 8 classes, 16 orders, 19 families, and 19 genera. Alpha and beta diversity analysis indicated significant differences in endophytic fungal communities among the various Taxus trees. At the genus level, Alternaria and Davidiella were predominantly found in T. mairei and T. media, respectively. By utilizing a previously published dataset, a Pearson correlation analysis was conducted to predict the taxol biosynthesis-related fungal genera. Following screening, two isolates of Alternaria (L7 and M14) were obtained. Effect of inoculation with Alternaria isolates on the gene expression and metabolite accumulation of T. mairei was determined by transcriptomic and untargeted metabolomic studies. The co-inoculation assay suggests that the two Alternaria isolates may have a negative regulatory effect on taxol biosynthesis by influencing hormone signaling pathways. Conclusion: Our findings will serve as a foundation for advancing the production and utilization of Taxus and will also aid in screening endophytic fungi related to taxol production. [ABSTRACT FROM AUTHOR]

Taxus contorta (family Taxaceae) is a native plant of temperate region of western Himalaya. The current study investigated the effect of altitude on the phytochemical composition and mycorrhizal diversity, associated with distribution of T. contorta in Shimla district, Himachal Pradesh, India. Quantitative phytochemical analysis of the leaf extracts indicated that alkaloid levels decreased with altitude, with the highest value in Himri's methanol extracts (72.79 ± 1.08 mg/g) while phenol content increased with altitude, peaking in Nankhari's methanol extracts (118.83 ± 5.90 mg/g). Saponin content was higher in methanol extracts (78.13 ± 1.66 mg/g in Nankhari, 68.06 ± 1.92 mg/g in Pabbas, and 56.32 ± 1.93 mg/g in Himri). Flavonoid levels were notably higher in chloroform extracts, particularly in Nankhari (219.97 ± 2.99 mg/g), and positively correlated with altitude. Terpenoids were higher in chloroform extracts at Himri (11.34 ± 0.10 mg/g) and decreased with altitude. Taxol content showed minimal variation between solvents and altitudes (4.53–6.98 ppm), while rutin was only detected in methanol extracts (1.31–1.46 ppm). Mycorrhizal spore counts in T. contorta's rhizosphere varied with altitude: highest at Himri (77.83 ± 2.20 spores/50 g soil), decreasing to Pabbas (68.06 ± 1.96 spores/50 g soil) and lowest at Nankhari (66.00 ± 2.77 spores/50 g soil), with 17 AMF species identified overall, showing significant altitudinal influence on spore density. The rhizosphere of T. contorta was shown to be dominated by the Glomus species. The rhizospheric soil of the plant was found to be slightly acidic. Organic carbon and available potassium content decreased contrasting with increasing available nitrogen and phosphorus with altitude. Correlation data showed strong negative links between organic carbon (−0.83), moderate positive for nitrogen (0.46) and phosphorus (0.414), and moderate negative for potassium (−0.56) with the altitude. This study provides a comprehensive insight into changes in phytochemical constituents, mycorrhizal diversity and soil composition of T. contorta along a range of altitude. [ABSTRACT FROM AUTHOR]

Taxus, a genus of conifers known for its medicinal significance, faces various conservation challenges with several species classified under different threat categories by the IUCN. The overharvesting of bark and leaves for the well-known chemotherapy drug paclitaxel has resulted in its population decline. Exploring the mycorrhizal relationship in Taxus is of utmost importance, as mycorrhizal fungi play pivotal roles in nutrition, growth, and ecological resilience. Taxus predominantly associates with arbuscular mycorrhizal fungi (AM), and reports suggest ectomycorrhizal (EM) or dual mycorrhizal associations as well. This review consolidates existing literature on mycorrhizal associations in Taxus species, focusing on structural, physiological, and molecular aspects. AM associations are well-documented in Taxus, influencing plant physiology and propagation. Conversely, EM associations remain relatively understudied, with limited evidence suggesting their occurrence. The review highlights the importance of further research to elucidate dual mycorrhizal associations in Taxus, emphasizing the need for detailed structural and physiological examinations to understand their impact on growth and survival. [ABSTRACT FROM AUTHOR]

Taxus cuspidata is a rare plant with important medicinal and ornamental value. Aiming at the obvious differences between wild and cultivated populations of T. cuspidata from Northeast China, a total of 61 samples, that is, 33 wild yews and 28 cultivated yews were used to analyze the differences and correlations of the kinship, genetic diversity, and genetic structure between them by specific length amplified fragment sequencing (SLAF-seq). Finally, 470725 polymorphic SLAF tags and 58622 valid SNP markers were obtained. Phylogenetic analysis showed that 61 samples were classified into 2 clusters: wild populations and cultivated populations, and some wild yews were categorized into the cultivated populations; the genetic diversity analysis showed that the Nei diversity index of wild populations (0.4068) was smaller than that of cultivated populations (0.4414), and the polymorphic information content (PIC) of wild populations (0.2861) was smaller than that of cultivated populations (0.3309). The genetic differentiation analysis showed that the total populations of gene diversity (Ht) of cultivated and wild populations were respectively 0.8159 and 0.5685, the coefficient of gene differentiation (Gst) of cultivated and wild populations was respectively 0.3021 and 0.1068, and the gene flow (Nm) (2.4967) of wild populations was larger than cultivated populations (0.8199). The molecular variance (AMOVA) revealed that inter-population variation accounted for 29.57% of the total genetic variation, while intra-population variation accounted for 70.42% of the total genetic variation (p < 0.001), this suggested that the genetic variation in the T. cuspidata is mainly attributed to within-population factors. In conclusion, the genetic distance between geographical ecological groups of wild populations was generally smaller than that of cultivated populations, and the degree of genetic diversity and genetic differentiation was smaller than that of cultivated populations. As evident, the utilization of SLAF-seq technology enables efficient and accurate development of SNP markers suitable for genetic analysis of T. cuspidata species. These developed SNP markers can provide a molecular foundation for T. cuspidata breeding, construction of genetic maps, variety identification, and association analysis of agronomic traits. [ABSTRACT FROM AUTHOR]

Taxus, commonly known as Yew, is a non-resinous evergreen tree renowned for its anti-cancer properties, attributed to the plant alkaloid Paclitaxel. This study draws upon secondary data sourced from reputable books, journals, and authenticated websites pertaining to the taxonomy of this significant flora. Taxus thrives in moist, humid, shady environments with slightly acidic soil, often flourishing beneath the canopies of species such as Abies, Fagus, Picea, and Quercus spp. The primary objective of this investigation was to evaluate the global status of the Taxus genus. Its distribution spans the northern hemisphere, with various regional common names associated with Taxus species. Through a comprehensive review, our findings reveal a total of 12 natural species and 2 hybrid species globally, including T. media Rehder and T. hunnewelliana Rehder. Notably, four Taxus species—T. chinensis Rehd., T. contorta Griff., T. globosa Schlect., and T. wallichiana Zucc—are endangered, while T. brevifolia Nuttall is categorized as near threatened according to the IUCN Red List. The updated Taxus genus database presented in this study serves as a valuable resource for diverse stakeholders, encompassing researchers, academicians, forest managers, herbal industry professionals, and policymakers. This information will help in formulating effective conservation strategies and sustainable utilization plans for this important genus.

The diterpenoid paclitaxel (Taxol) is a chemotherapy medication widely used as a first-line treatment against several types of solid cancers. The supply of paclitaxel from natural sources is limited. However, missing knowledge about the genes involved in several specific metabolic steps of paclitaxel biosynthesis has rendered it difficult to engineer the full pathway. In this study, we used a combination of transcriptomics, cell biology, metabolomics, and pathway reconstitution to identify the complete gene set required for the heterologous production of paclitaxel. We identified the missing steps from the current model of paclitaxel biosynthesis and confirmed the activity of most of the missing enzymes via heterologous expression in Nicotiana benthamiana. Notably, we identified a new C4β-C20 epoxidase that could overcome the first bottleneck of metabolic engineering. We used both previously characterized and newly identified oxomutases/epoxidases, taxane 1β-hydroxylase, taxane 9α-hydroxylase, taxane 9α-dioxygenase, and phenylalanine-CoA ligase, to successfully biosynthesize the key intermediate baccatin III and to convert baccatin III into paclitaxel in N. benthamiana. In combination, these approaches establish a metabolic route to taxoid biosynthesis and provide insights into the unique chemistry that plants use to generate complex bioactive metabolites. Genes specific for several steps of paclitaxel biosynthesis have not been identified, hindering metabolic engineering of the full pathway in heterologous systems. This study identifies four new genes (C4β-C20 epoxidase, taxane 1β-hydroxylase, taxane 9α-hydroxylase, taxane 9α-dioxygenase) involved in paclitaxel biosynthesis. When these four genes were co-expressed with previously characterized enzymes, the key intermediate baccatin III was successfully biosynthesized in N. benthamiana. Paclitaxel could be further biosynthesized from baccatin III by adding a newly identified phenylalanine-CoA ligase. [ABSTRACT FROM AUTHOR]

Taxus L. is accepted in the literature as natural resources of biologically active compounds and volatile oils, with applications in medicine, pharmaceuticals, food, cosmetics, and with ecological impact on the natural living environment. In this context, the present work aims to analyze by GS/MS techniques the chemical composition of volatile oil obtained by hydrodistillation of leaves harvested from spontaneous and cultivated female individuals of Taxus (dried and fresh plant material) and to spectrophotometrically evaluate the hydrosols resulting from their hydrodistillation. The compounds with the highest concentrations in the volatile oil obtained from the spontaneous taxon Taxus baccata L. were hexahydrofarnesyl acetone (33.03% fresh leaves; 20.09% dried leaves); ar-abietatriene (14.98% dried leaves; 3.03% fresh leaves); phthalic acid, hex-3-yl isobutyl ester (10.51% dried leaves); salicylic acid, benzyl ester (8.11% dried leaves). In the cultivated taxon Taxus baccata the compounds identified with the highest concentrations were 1-octen-3-ol (25.61% fresh leaves); phytol (12.50% dry leaves); geranyl acetone (11.90% dry leaves); manoyl oxide (11.85% dry leaves; 10.86% fresh leaves); 1,9-decadence (7.92% fresh leaves). The compounds with the highest concentrations in the oil extracted from the leaves of Taxus baccata 'Robusta' were hexahydrofarnesyl acetone (17.81% fresh leaves); pentacosane (11.28% dry leaves); heptacosane (11.27% fresh leaves); tetracosane (11.13% dry leaves); tricosane (8.45% fresh leaves). The chemical composition of volatile oils from yew is influenced by many exogenous factors such as soil, light, and endogenous factors such as age, DNA. [ABSTRACT FROM AUTHOR]

At the Taxus base of Pengshui Miao and Tujia Autonomous County, Chongqing, the comprehensive development and utilization of Taxus was carried out with seedling cultivation, understory economy, product processing, ecotourism and other aspects as the main line. The benefit linkage mechanism of the operation of the Taxus industrial chain was explored and analyzed, so as to extend and supplement the Taxus industrial chain. The two models of "company + farmer" and "company + village collective + farmer" are relatively close benefit linkage models, which indirectly promote the increase of farmers' income and smoothly guarantee the operation of the industrial chain, thereby playing a positive role during the development of the Taxus industry. This study provides reliable countermeasures and suggestions for the sustained and healthy development of the Taxus industry in Pengshui County. [ABSTRACT FROM AUTHOR]

Taxus L. is accepted in the literature as natural resources of biologically active compounds and volatile oils, with applications in medicine, pharmaceuticals, food, cosmetics, and with ecological impact on the natural living environment. In this context, the present work aims to analyze by GS/MS techniques the chemical composition of volatile oil obtained by hydrodistillation of leaves harvested from spontaneous and cultivated female individuals of Taxus (dried and fresh plant material) and to spectrophotometrically evaluate the hydrosols resulting from their hydrodistillation. The compounds with the highest concentrations in the volatile oil obtained from the spontaneous taxon Taxus baccata L. were hexahydrofarnesyl acetone (33.03% fresh leaves; 20.09% dried leaves); ar-abietatriene (14.98% dried leaves; 3.03% fresh leaves); phthalic acid, hex-3-yl isobutyl ester (10.51% dried leaves); salicylic acid, benzyl ester (8.11% dried leaves). In the cultivated taxon Taxus baccata the compounds identified with the highest concentrations were 1-octen-3-ol (25.61% fresh leaves); phytol (12.50% dry leaves); geranyl acetone (11.90% dry leaves); manoyl oxide (11.85% dry leaves; 10.86% fresh leaves); 1,9-decadence (7.92% fresh leaves). The compounds with the highest concentrations in the oil extracted from the leaves of Taxus baccata ‘Robusta’ were hexahydrofarnesyl acetone (17.81% fresh leaves); pentacosane (11.28% dry leaves); heptacosane (11.27% fresh leaves); tetracosane (11.13% dry leaves); tricosane (8.45% fresh leaves). The chemical composition of volatile oils from yew is influenced by many exogenous factors such as soil, light, and endogenous factors such as age, DNA.

Representative species of the Taxus genus, known since antiquity for their toxicity, have been an essential plant resource for the production of plant extracts with medicinal properties (antiinflammatory, antifungal, and antibacterial) and, more recently, for the study of their allelopathic properties with significant implications in organic agriculture (bioherbicidal potential). With a view to the development of this new direction of research, the present work aims: to present a qualitative evaluation of two types of plant extracts (aqueous and alcoholic) of different concentrations (1% and 5%) obtained from various organs (bark, leaves, arils, and seeds) belonging to three Taxus taxa: a spontaneous taxa - Taxus baccata L. (T1) and two cultivated taxa - Taxus baccata (T2) and Taxus baccata 'Robusta' (T3) at different times of the phenological cycle by determining their absorption spectra (of both types of extracts), total amounts of polyphenols and flavonoids, and by evaluating their antioxidant capacity (alcoholic extracts); to investigate, under experimental conditions of cultivation the possible allelopathic effects induced by the aqueous extracts on the germination, growth, and development of the seedlings in two test plant species: Amaranthus retroflexus L. (ruderal species) and Lycopersicon esculentum Mill, variety Silvia (crop species). The data indicates the presence of phenolic and compounds, alkaloids, and carotenoid pigments in the alcoholic extracts prepared from the different organs of the studied yew taxa, showing higher amounts of polyphenols and flavonoids in the extracts obtained from the leaves of taxon T2 compared to taxon T1. The effect of 1% and 5% aqueous extracts obtained from the bark of the three investigated yew taxa, as well as 1% aqueous extracts prepared from the leaves of taxon T3 on seed germination, seedling growth, and development was more pronounced in the crop species Lycopersicon esculentum Mill, variety Silvia, compared to the ruderal broadleaf weed Amaranthus retroflexus L., both species having rapid germination stimulated by ambient light. Aqueous extracts of 5% concentration obtained from the arils of plants belonging to the three yew taxa stimulated the elongation of the seedlings' hypocotyls of both test species. [ABSTRACT FROM AUTHOR]

To determine the electrical impedance parameters suitable for the determination of semi-lethal low temperature of Taxus and explore the effects of low temperature on the taxane biosynthesis in Taxus, the electrical impedance parameters and taxane content changes of Taxus under low temperature stress were examined. It will lay a theoretical foundation for expanding the introduction range of Taxus and using low temperature conditions to increase the contents of taxane content in Taxus. Using T. yunnanensis, T. chinensis var. mairei (Changzhi, Shanxi), T. chinensis, T. cuspidata and T. × media as materials, the semi-lethal low temperature of these trees were determined by conductivity method and electrical impedance method respectively. Moreover, the taxane contents and abscisic acid contents in the leaves of Taxus under low-temperature stress were determined by LC-MS method. The results showed that T. chinensis, T. chinensis var. mairei (Changzhi, Shanxi), T. cuspidata and T. × media all tolerated low temperature of -14.668- -9.106℃. The T. yunnanensis tolerated -8.802- -3.521℃, which was higher than the ons of other four Taxus species. The semi-lethal low temperature of one-year-old branches of five Taxus measured by electrical impedance τm parameter was significantly correlated with that measured by conductivity method, and the correlation coefficient was 0.912. The taxol content in the leaves of one-year-old Taxus was higher than that in the current-year under low temperature stress. The taxol content in the leaves of one-year-old T. yunnanensis and T. cuspidata significantly increased with the decrease of treatment temperature, while the baccatin III content and 10-deacetyltaxol content in the leaves of one-year-old T. chinensis significantly increased. Moreover, ABA content in the leaves of Taxus increased with the decrease of temperature, and ABA content in the current-year leaves was higher than that in the one-year-old leaves. Compared with T. yunnanensis, T. chinensis, T. chinensis var. mairei (Changzhi, Shanxi), T. cuspidata and T. × media tolerated lower temperature. Low temperature is beneficial to the synthesis of taxol in the leaves of one-year-old T. yunnanensis and T. cuspidata, and the synthesis of baccatin III and 10-deacetyltaxol in the leaves of current-year T. chinensis. [ABSTRACT FROM AUTHOR]

Taxane diterpenoids (taxoids) are found only in representatives of the Taxaceae family (different yew species); however, the unique structure and therapeutic properties of taxoids, which are in demand in medicine, have made these compounds one of the most studied secondary metabolites of higher plants. In this work, for the first time, a detailed study is performed into the structural diversity of polyesters of 14-hydroxylated taxoids in Taxus canadensis a yew species, for intact plants of which nonpolar 14-hydroxylated taxoids have not been previously described. At the first stage of the work, it was shown using chromato-mass spectrometry that polyesters of 14-hydroxylated taxoids (yunnanxan, taxuyunnanin C, sinenxan B, sinenxan C) are the dominant diterpenoid secondary metabolites in T. canadensis callus cell culture. Based on these results, as well as the similarity of the metabolism of cultivated in vitro plant cells and root cells in planta, it was suggested that polyesters of 14-hydroxylated taxoids will preferentially accumulate in the roots in intact T. canadensis plants. The validity of this hypothesis was confirmed using liquid chromatography-mass spectrometry and nuclear magnetic resonance spectroscopy (NMR). According to chromato-mass-spectrometric screening in T. canadensis needles, polyesters of 14-hydroxylated taxoids are actually found only in trace amounts, while they are one of the major (quantitatively) diterpenoids in the roots. One of the main 14-hydroxylated taxoids of T. canadensis roots, yunnanxan, was isolated preparatively and uniquely identified using NMR spectroscopy and high-resolution mass spectrometry. This work is the first report on the presence of polyesters of 14-hydroxylated taxoids in intact Canadian yew plants. [ABSTRACT FROM AUTHOR]

Taxus cuspidata S. et Z. is a precious species of frigid zone plant belonging to the Taxaceae family, which possesses anticancer, anti-inflammatory, hypoglycemic, and antibacterial pharmacological properties. While taxane extracted from Taxus chinensis has been reported to elicit antioxidant activities, whether Taxus cuspidata S. et Z. has skin-protective actions against injuries remained unknown. This study aims to explore the pharmacological effects of three Taxus extracts on skin melanin deposition, oxidation, inflammation, and allergy so as to provide new ideas for the prevention and treatment of various diseases related to skin damage. Skin melanin deposition was evaluated by measuring melanin content in the skin of guinea pigs by alkali lysis method. Antioxidant capacity was evaluated by measuring superoxide dismutase (SOD) concentration and glutathione (GSH) content in skin tissue homogenates of Kunming mice by SOD assay kit and micro reduced GSH assay kit. The quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting were used to examine the levels of both SOD and recombinant glutathione peroxidase 4 (GPX4). Skin inflammation was evaluated by xylene-induced ear swelling test and egg-white-induced paw swelling test in mice. In a mouse model of skin allergy induced by 4-aminopyridine (4-AP), allergy was determined by licking body counts and histamine concentrations in tissue homogenates using enzyme-linked immunosorbent assay (ELISA) kits. Two proinflammatory factors tumor necrosis factor (TNF)-α and interleukin (IL)-1β were measured by qRT-PCR. Hematoxylin and eosin (HE) staining was conducted to assess the degree of skin lesion. All three Taxus extracts including Taxus chinensis essential oil, Taxus chinensis extract and Taxus chinensis extract compound reduced the melanin deposits in the back skin relative to the non-treated control animals, of which Taxus chinensis essential oil produced the greatest effect. In contrast, the three Taxus extracts elevated SOD and GSH levels in the skin tissues, and the highest increase was seen with Taxus chinensis essential oil. Three Taxus extracts, especially Taxus chinensis essential oil, effectively reduce the rate of ear and paw swelling. All three Taxus extracts reduced the number of body licks, the levels of TNF-α and IL-1β, and the histamine content in tissue homogenates of mice and alleviated skin damage. Consistently, Taxus chinensis essential oil yielded the greatest magnitude of decreases. While all three Taxus extracts possessed the anti-skin melanin deposition, oxidation, and allergy properties, Taxus chinensis essential oil produced the superior effects. [ABSTRACT FROM AUTHOR]

Three species of Taxus occur in Nepal T. contorta, T. maireii and Taxus wallichiana,. All are under pressure from collection for medicinal use, habitat destruction and changing land use. In 2017 and 2018 fieldwork was carried out to collect seed, herbarium specimens, cuttings and information to improve protection of these species, funded by Fondation Franklinia. Collections were made for propagation, herbarium and molecular studies. Population level Information was also gathered to make national assessments for these species. This article traces the status of the living collections in the National Botanic Garden of Nepal (NBG) and the assessments made by the team comprising staffs of Department of Plant Resources (DPR) and Nepal Academy of Science and Technology (NAST) and Freelance botanist. Reference is made to work done prior to 2017 on the taxonomy and distribution of the species and which enabled efficient fieldwork thereafter. The establishment of a conservation collection at NBG provides a basis for research into yew species in Nepal and highlights the benefits of internationally collaborative projects to maintain conservation collections of threatened species in their country of origin.

Key message: Paclitaxel synthesis in Taxus cells correlates with a cell-fate switch that leads to vacuoles of a glossy appearance and vermiform mitochondria. This switch depends on actin and apoplastic respiratory burst. Plant cell fermentation, the production of valuable products in plant cell culture, has great potential as sustainable alternative to the exploitation of natural resources for compounds of pharmaceutical interest. However, the success of this approach has remained limited, because the cellular aspects of metabolic competence are mostly unknown. The production of the anti-cancer alkaloid Paclitaxel has been, so far, the most successful case for this approach. In the current work, we map cellular aspects of alkaloid synthesis in cells of Taxus chinensis using a combination of live-cell imaging, quantitative physiology, and metabolite analysis. We show evidence that metabolic potency correlates with a differentiation event giving rise to cells with large vacuoles with a tonoplast that is of a glossy appearance, agglomerations of lipophilic compounds, and multivesicular bodies that fuse with the plasma membrane. Cellular features of these glossy cells are bundled actin, more numerous peroxisomes, and vermiform mitochondria. The incidence of glossy cells can be increased by aluminium ions, and this increase is significantly reduced by the actin inhibitor Latrunculin B, and by diphenylene iodonium, a specific inhibitor of the NADPH oxidase Respiratory burst oxidase Homologue (RboH). It is also reduced by the artificial auxin Picloram. This cellular fingerprint matches the implications of a model, where the differentiation into the glossy cell type is regulated by the actin–auxin oscillator that in plant cells acts as dynamic switch between growth and defence. [ABSTRACT FROM AUTHOR]

As a relict plant, Taxus is used in a variety of medicinal ingredients, for instance to treat a variety of cancers. Taxus plants are difficult to distinguish from one another due to their similar morphology; indeed, some species of Taxus cytogenetic data still are unclear. Oligo-FISH can rapidly and efficiently provide insight into the genetic composition and karyotype. This is important for understanding the organization and evolution of chromosomes in Taxus species. We analysed five Taxus species using two oligonucleotide probes. (AG3T3)3 signals were distributed at the chromosome ends and the centromere of five species of Taxus. The 5S rDNA signal was displayed on two chromosomes of five species of Taxus. In addition to Taxus wallichiana var. mairei, 5S rDNA signals were found proximal in the remaining four species, which signals a difference in its location. The karyotype formula of Taxus wallichiana was 2n = 2x = 24m, its karyotype asymmetry index was 55.56%, and its arm ratio was 3.0087. Taxus × media's karyotype formula was 2n = 2x = 24m, its karyotype asymmetry index was 55.09%, and its arm ratio was 3.4198. The karyotype formula of Taxus yunnanensis was 2n = 2x = 24m, its karyotype asymmetry index was 55.56%, and its arm ratio was 2.6402. The karyotype formula of Taxus cuspidate was 2n = 2x = 24m, its karyotype asymmetry index was 54.67%, its arm ratio was 3.0135, and two chromosomes exhibited the 5S rDNA signal. The karyotype formula of T. wallichiana var. mairei was 2n= 2x = 22m + 2sm, its karyotype asymmetry index was 54.33%, and its arm ratio was 2.8716. Our results provide the karyotype analysis and physical genetic map of five species of Taxus, which contributes to providing molecular cytogenetics data for Taxus. [ABSTRACT FROM AUTHOR]

The taxonomy of an ancient gymnosperm genus Taxus, with high value in horticulture and medicine, is perplexing because of few reliable morphological characters for diagnosing species. Here, we performed a comprehensive investigation of the evolutionary dynamics of Taxus chloroplast genomes and estimated phylogenetic relationships, divergence times, and ancestral distributions of Taxus species by comparing 18 complete chloroplast genomes. The variations across the chloroplast genome of different Taxus species indicated that remarkably varied genome variations across lineages have reshaped the genome architecture. Our well-resolved phylogeny supported that T. brevifolia Nutt. was basal lineages followed by the other North America lineages. Divergence time estimation and ancestral range reconstruction suggested that the Taxus species originated in North America in the Late Cretaceous and revealed that extant Taxus species shared a common ancestor whose ancestral distribution area was probably in North America and afterwards the earliest members expanded to Southeast Asia from where Chinese Taxus species originated. The predominant European species have more closer relationship with the Eastern Asian species and the speciation of Eurasia species arose from several dispersal and vicariance events in the Miocene. Genome-wide scanning revealed 18 positively selected genes that were involved in translation and photosynthesis system in Taxus, which might be related to the adaptive evolution of Taxus species. The availability of these complete chloroplast genomes not only enhances our understanding of the elusive phylogenetic relationships and chloroplast genome evolution such as conservation, diversity, and gene selection within Taxus genus but also provides excellent templates and genetic bases for further exploration of evolution of related lineages as well as for plant breeding and improvement. [ABSTRACT FROM AUTHOR]

Ethnopharmacological Relevance: Acquired resistance to osimertinib limits its clinical efficacy in non-small cell lung cancer (NSCLC) with EGFR mutations. The widespread recognition of Taxus chinensis var. Mairei (Lemée et Lévl) Cheng et L.K. Fu (Chinese yew) as a natural anti-cancer medication is well-established. However, the specific contribution of Taxus chinensis var. Mairei (Lemée et Lévl) Cheng et L.K. Fu in addressing resistance to osimertinib is still uncertain., Aim of the Study: Based on the biological behaviors and lipid metabolism, we investigated whether aqueous extract of Taxus chinensis var. Mairei (Lemée et Lévl) Cheng et L.K. Fu (AETC) could enhance the antitumor effect of osimertinib in NSCLC with an investigation on the precise mechanisms., Materials and Methods: The effect of AETC on enhancing osimertinib sensitivity was assessed via cell viability measurements, levels of reactive oxygen species (ROS), apoptosis, and lipid levels. Western blotting was used to verify the mechanisms of AETC responsible for overcoming the resistance to osimertinib via ERK1/2 overexpression and knockdown models. In vivo validation was conducted using subcutaneous xenografts from osimertinib-resistant cells in nude mice., Results: Osimertinib-resistant cells exhibited altered cholesterol biosynthesis, which was induced by ERK1/2 activation. The combination of AETC and osimertinib can synergistically decrease the levels of ROS in cells, enhance apoptosis, and inhibit the growth of osimertinib-resistant cells. Mechanistic experiments demonstrated that AETC can downregulate the key regulators of cholesterol biosynthesis by regulating ERK1/2, inhibiting the endogenous synthesis rate of cholesterol, and suppressing the level of lipids in osimertinib-resistant cells and xenograft tumors when combined with osimertinib, ultimately reversing resistance to osimertinib., Conclusions: The resistance to osimertinib is significantly influenced by cholesterol biosynthesis, highlighting its pivotal role in this context. AETC can enhance osimertinib sensitivity via ERK/SREBP-2/HMGCR-mediated cholesterol biosynthesis. These results provide a promising therapeutic target and potential treatment option for resistance to osimertinib., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

In this paper, the leaves of Taxus were used as the sole carbon source, and two kinds of carbon dots blue and red, with different properties, were synthesized by the hydrothermal method under different conditions. The red carbon dots were quenched in the water, and the blue carbon dots had stable fluorescence properties in water environment. The bimodal fluorescence probe formed by mixing could accurately and stably measure the water content in ethanol, which was in the range of 82.5%-100%, is highly correlated with the fluorescence intensity ratio (I481/I678) of mixed carbon dots under 390 nm excitation light, with R2 = 0.995 and the detection limit as low as 0.31%. The experimental materials are environmentally friendly, low in cost, and simple to operate, as well as the water content measured by proportional fluorescence has high accuracy, which provides a new method for measuring moisture in ethanol. [ABSTRACT FROM AUTHOR]

In this paper leaf structure of 4 Taxus species and varieties (Taxus baccata, T. baccata var. fastigiata, T. brevifolia, Taxus cuspidata) was investigated. Histological and micromorphological studies were carried out by light and scanning electron microscopy. From the histo-anatomical point of view, the leaf shows a general structural pattern with palisade and spongy parenchyma. This is common to all investigated taxa with quantitative variations. The stomata are located only in the lower epidermis (hypostomatic leaves), being disposed on 2 bands, with different widths, on one side and the other of the midrib. The papillae of the cells from the lower epidermis are also visible next to the median rib, with the exception of the species T. brevifolia. The palisade parenchyma is bilayered, with short cells. The structural characters of the leaves have taxonomical significance. The importance of the structural features of the leaf in the adaptation of the species to the living environment were emphasized. [ABSTRACT FROM AUTHOR]

Taxus plants are the exclusive source of paclitaxel, an anticancer drug with significant medicinal and economic value. Interspecies hybridization and gene introgression during evolution have obscured distinctions among Taxus species, complicating their phylogenetic classification. While the chloroplast genome of Taxus wallichiana , a widely distributed species in China, has been sequenced, its mitochondrial genome (mitogenome) remains uncharacterized.We sequenced and assembled the T. wallichiana mitogenome using BGI short reads and Nanopore long reads, facilitating comparisons with other gymnosperm mitogenomes. The T. wallichiana mitogenome spanning 469,949 bp, predominantly forms a circular configuration with a GC content of 50.51%, supplemented by 3 minor configurations mediated by one pair of LRs and two pairs of IntRs. It includes 32 protein-coding genes, 7 tRNA genes, and 3 rRNA genes, several of which exist in multiple copies.We detailed the mitogenome's structure, codon usage, RNA editing, and sequence migration between organelles, constructing a phylogenetic tree to elucidate evolutionary relationships. Unlike typical gymnosperm mitochondria, T. wallichiana shows no evidence of mitochondrial-plastid DNA transfer (MTPT), highlighting its unique genomic architecture. Synteny analysis indicated extensive genomic rearrangements in T. wallichiana , likely driven by recombination among abundant repetitive sequences. This study offers a high-quality T. wallichiana mitogenome, enhancing our understanding of gymnosperm mitochondrial evolution and supporting further cultivation and utilization of Taxus species. • Successfully assembled the mitochondrial genome of Taxus wallichiana , revealing a primary circular configuration supplemented by three minor configurations mediated by repeated sequences; • Identified that the T. wallichiana mitogenome shows no evidence of mitochondrial-plastid DNA transfer (MTPT), highlighting its unique genomic architecture compared to typical gymnosperms. • Phylogenetic analysis elucidated the evolutionary relationships of T. wallichiana with other gymnosperms, providing new insights into mitogenome evolution, particularly the impact of recombination and repeated sequences on genome structure. [ABSTRACT FROM AUTHOR]

Background: Brevifoliol is a diterpenoid that occurs naturally in the plants of Taxus genus and is widely used as chemotherapy agent for the management of cancer. A series of semisynthetic esters analogues of brevifoliol were prepared by Steglich esterification and attempted for their pharmacological potential against insulin resistance conditions using in-vitro and in-silico assays., Objective: The aim of this study is to understand the pharmacological potential of eighteen semisynthetic analogs through Steglich esterification of Brevifoliol against insulin resistance condition Methods: In the in-vitro study, insulin resistance condition was induced in skeletal muscle cells using TNF-α, pro-inflammatory cytokine and these cells were treated with brevifoliol analogues. The most potent analouge was further validated using in-silico docking study against the tumor necrosis factor (TNF-α) (PDB ID: 2AZ5) and Human Insulin Receptor (PDB ID: 1IR3), using the Auto dock Vina v0.8 program., Results: Although, all the analogues of Brevifoliol significantly exhibited the pharmacological potential. Among all, analogue 17 was most potent in reversing the TNF-α induced insulin resistance condition in skeletal muscle cells and also to inhibit the production of TNF-α in LPSinduced inflammation in macrophage cells in a dose-dependent manner. Similarly, in-silico molecular docking studies revealed that analogue 17 possesses a more promising binding affinity than the selected control drug metformin toward the TNF-α and insulin receptor., Conclusion: These findings suggested the suitability of analogue 17 as a drug-like candidate for further investigation toward the management of insulin resistance conditions., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Taxus, commonly known as yew, is a well-known gymnosperm with great ornamental and medicinal value. In this study, by assembling a chromosome-level genome of the Himalayan yew (Taxus wallichiana) with 10.9 Gb in 12 chromosomes, we revealed that tandem duplication acts as the driving force of gene family evolution in the yew genome, resulting in the main genes for paclitaxel biosynthesis, i.e. those encoding the taxadiene synthase, P450s, and transferases, being clustered on the same chromosome. The tandem duplication may also provide genetic resources for the nature to sculpt the core structure of taxoids at different positions and subsequently establish the complex pathway of paclitaxel by neofunctionalization. Furthermore, we confirmed that there are two genes in the cluster encoding isoenzymes of a known enzyme in the paclitaxel biosynthetic pathway. The reference genome of the Himalayan yew will serve as a platform for decoding the complete biosynthetic pathway of paclitaxel and understanding the chemodiversity of taxoids in gymnosperms. In this study, we presented the chromosome-level genome assembly for the Himalayan yew and revealed that tandem duplication was a driving force of the evolution of Taxol biosynthetic pathway in the yew genome, which not only clustered 90% the known genes in the pathway on the same chromosome, but also provided a plentiful of genetic resources for nature to shape this complex pathway. The reference genome of Taxus would be a great platform for decoding the complete biosynthetic pathway of Taxol and other taxoids. [ABSTRACT FROM AUTHOR]

Abstract Background Trees of the genus Taxus are highly valuable medicinal plants with multiple pharmacological effects on various cancer treatments. Paclitaxel from Taxus trees is an efficient and widely used anticancer drug, however, the accumulation of taxoids and other active ingredients can vary greatly among Taxus species. In our study, the metabolomes of three Taxus species have been investigated. Results A total of 2246 metabolites assigned to various primary and secondary metabolic pathways were identified using an untargeted approach. Analysis of differentially accumulated metabolites identified 358 T. media-, 220 T. cuspidata-, and 169 T. mairei-specific accumulated metabolites, respectively. By searching the metabolite pool, 7 MEP pathway precursors, 11 intermediates, side chain products and derivatives of paclitaxel, and paclitaxel itself were detected. Most precursors, initiated intermediates were highly accumulated in T. mairei, and most intermediate products approaching the end point of taxol biosynthesis pathway were primarily accumulated in T. cuspidata and T. media. Our data suggested that there were higher-efficiency pathways to paclitaxel in T. cuspidata and T. media compared with in T. mairei. As an important class of active ingredients in Taxus trees, a majority of flavonoids were predominantly accumulated in T. mairei rather than T. media and T. cuspidata. The variations in several selected taxoids and flavonoids were confirmed using a targeted approach. Conclusions Systematic correlativity analysis identifies a number of metabolites associated with paclitaxel biosynthesis, suggesting a potential negative correlation between flavonoid metabolism and taxoid accumulation. Investigation of the variations in taxoids and other active ingredients will provide us with a deeper understanding of the interspecific differential accumulation of taxoids and an opportunity to accelerate the highest-yielding species breeding and resource utilization.

MicroRNAs (miRNAs) have been shown to play key roles in the regulation of plant growth and development by modifying the expression of their target genes. However, the influence of miRNAs on root formation and development in woody plants, such as Taxus chinensis, remains largely unknown. In the current study, we explored the phytohormone-response and nutrition-response miRNA expression profiles during T. chinensis rooting by quantitative real-time PCR (qPCR). We identified six phytohormone-response miRNAs, namely, miR164a, miR165, miR167a, miR171b, miR319, and miR391, and eight nutrition-response miRNAs, namely, miR169b, miR395a, miR399c, miR408, miR826, miR827, miR857, and miR2111a, that were differentially expressed at different rooting phases of T. chinensis. Using northern blot analysis of the putative target genes of these miRNAs, we detected the relative gene expression changes of the target genes. Taken together, our results suggest that miRNAs are involved in root formation of T. chinensis and that miRNAs may play important regulatory roles in primary root, crown root, and root hair formation by targeting phytohormone and/or nutrition response genes in T. chinensis. For the first time, these results expand our understanding of the molecular mechanisms of plant root formation and development in a conifer species.

Abstract Background Taxol is an efficient anticancer drug; however, the accumulation of taxoids can vary hugely among Taxus species. The mechanism underlying differential accumulation of taxoids is largely unknown. Thus, comparative analysis of the transcriptomes in three Taxus species, including T. media, T. mairei and T. cuspidata, was performed. Results KEGG enrichment analysis revealed that the diterpenoid biosynthesis and cytochrome P450 pathways were significantly enriched in different comparisons. Differential expressions of these taxol biosynthesis related genes might be a potential explanation for the interspecific differential accumulation of taxol and its derivatives. Besides, the sequences of several MEP pathway-associated genes, such as DXS, DXR, MCT, CMK, MDS, HDS, HDR, IPPI, and GGPPS, were re-assembled based on independent transcriptomes from the three Taxus species. Phylogenetic analysis of these MEP pathway-associated enzymes also showed a high sequence similarity between T. media and T. cuspidata. Moreover, 48 JA-related transcription factor (TF) genes, including 10 MYBs, 5 ERFs, 4 RAPs, 3 VTCs, and 26 other TFs, were analyzed. Differential expression of these JA-related TF genes suggested distinct responses to exogenous JA applications in the three Taxus species. Conclusions Our results provide insights into the expression pattern and sequence similarity of several taxol biosynthesis-related genes in three Taxus species. The data give us an opportunity to reveal the mechanism underlying the variations in the taxoid contents and to select the highest-yielding Taxus species.

Paclitaxel (PTX) is a high value plant natural product (PNP) derived from Taxus (yew) species. This plant secondary metabolite (PSM) and its derivatives constitute a cornerstone for the treatment of an increasing variety of cancers. New applications for PTX also continue to emerge, further promoting demand for this WHO designated essential medicine. Here we review recent advances in our understanding of PTX biosynthesis and its cognate regulation, which have been enabled by the development of transcriptomic approaches and the recent sequencing and annotation of three Taxus genomes. Collectively, this has resulted in the elucidation of two functional gene sets for PTX biosynthesis, unlocking new potential for the use of heterologous hosts to produce PTX. Knowledge of the PTX pathway also provides a valuable resource for understanding the regulation of this key PSM. Epigenetic regulation of PSM in plant cell culture (PCC) is a major concern for PTX production, given the loss of PSM production in long-term cell cultures. Recent developments aim to design tools for manipulating epigenetic regulation, potentially providing a means to reverse the silencing of PSM caused by DNA methylation. Exciting times clearly lie ahead for our understanding of this key PSM and improving its production potential., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Many popular ornamental shrubs are not only beautiful but also toxic when ingested in sufficient quantities. Common toxic landscaping shrubs in North America include yew (Taxus spp), oleander (Nerium oleander), and rhododendrons and azaleas (Rhododendron spp). Horses are often exposed when plant trimmings are placed within reach or discarded in pastures. Occasionally clippings or fallen leaves contaminate hay. Some plants are unpalatable unless dried and mixed with hay or lawn clippings but others are ingested more readily. In many cases, disease can be severe and treatment unrewarding; therefore, client education is critical to preventing serious and potentially fatal poisonings., Competing Interests: Disclosure The author has nothing to disclose., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Abstract Background Plants of the genus Taxus have attracted much attention owing to the natural product taxol, a successful anti-cancer drug. T. fuana and T. yunnanensis are two endangered Taxus species mainly distributed in the Himalayas. In our study, an untargeted metabolomics approach integrated with a targeted UPLC-MS/MS method was applied to examine the metabolic variations between these two Taxus species growing in different environments. Results The level of taxol in T. yunnanensis is much higher than that in T. fuana, indicating a higher economic value of T. yunnanensis for taxol production. A series of specific metabolites, including precursors, intermediates, competitors of taxol, were identified. All the identified intermediates are predominantly accumulated in T. yunnanensis than T. fuana, giving a reasonable explanation for the higher accumulation of taxol in T. yunnanensis. Taxusin and its analogues are highly accumulated in T. fuana, which may consume limited intermediates and block the metabolic flow towards taxol. The contents of total flavonoids and a majority of tested individual flavonoids are significantly accumulated in T. fuana than T. yunnanensis, indicating a stronger environmental adaptiveness of T. fuana. Conclusions Systemic metabolic profiling may provide valuable information for the comprehensive industrial utilization of the germplasm resources of these two endangered Taxus species growing in different environments.

The genus Taxus is well known for its anticancer metabolite, paclitaxel. Recent releases of chromosome-scale reference genomes for two Taxus species (Xiong et al. and Cheng et al.) now provide novel insights on genome structure and phylogenomics and the origin and evolution of the paclitaxel biosynthesis pathway. [ABSTRACT FROM AUTHOR]

Quantitative real-time PCR (qRT-PCR) is commonly used to measure gene expression to further explore gene function, while suitable reference genes must be stably expressed under different experimental conditions to obtain accurate and reproducible data for relative quantification. Taxol or paclitaxel is an important anticancer compound mainly identified in Taxus spp. The molecular mechanism of the regulation of taxol biosynthesis is current research goal. However, in the case of Taxus spp., few reports were published on screening suitable reference genes as internal controls for qRT-PCR. Here, eight reference genes were selected as candidate reference genes for further study. Common statistical algorithms geNorm, NormFinder, BestKeeper, ΔCt, and RefFinder were used to analyze the data from samples collected from a cell line of Taxus × media under various experimental conditions and from tissues of Taxus chinensis var. mairei. The expression patterns of TcMYC under salicylic acid treatment differed significantly, with the best and worst reference genes in the cell line. This study screened out suitable reference genes (GAPDH1 and SAND) under different treatments and tissues for the accurate and reliable normalization of the qRT-PCR expression data of Taxus spp. At the same time, this study will aid future research on taxol biosynthesis-related genes expression in Taxus spp., and can also be directly used to other related species. [ABSTRACT FROM AUTHOR]

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Taxus is a genus of trees and shrubs with high value in horticulture and medicine as a source of the anticancer drug paclitaxel. The taxonomy of the group is complex due to the lack of diagnostic morphological characters and the high degree of similarity among species. Taxus has a wide global geographic distribution and some taxonomists recognize only a single species with geographically defined subgroups, whereas others have described several species. To address these differences in taxonomic circumscription, phylogenetic analyses were conducted on DNA sequences using Maximum Likelihood, Bayesian Inference and TCS haplotype networks on single and combined gene regions obtained for the nuclear ribosomal ITS region and the plastid trnL intron and trnL-F intergenic spacer. Evidence is presented for the sister group status of Pseudotaxus to Taxus and the inclusion of Amentotaxus, Austrotaxus, Cephalotaxus and Torreya within Taxaceae. Results are consistent with the taxonomic recognition of nine species: T. baccata, T. brevifolia, T. canadensis, T. cuspidata, T. floridana, T. fuana, T. globosa, T. sumatrana and T. wallichiana, but evidence is found for less species distinction and considerable reticulation within the T. baccata, T. canadensis and T. cuspidata group. We compare the results to known taxonomy, biogeography, present new leaf anatomical data and discuss the origins of the hybrids T. Xmedia and T. Xhunnewelliana. [ABSTRACT FROM AUTHOR]