ABSTRACT
The formation of high-quality Chinese medicinal materials is a micro-evolutionary process of multiple genes involving quantitative inheritance under environmental stress. Atractylodes lancea is a traditionally used medicinal plant in China that is broadly distributed and possesses a considerable amount of essential oils. However, to date, limited research has been conducted to characterize the genetics and metabolites of A. lancea shaped by natural variation. Hence, we assembled a high-quality genome of A. lancea, featuring a contig N50 of 1.18 Mb. We further integrated population resequencing of A. lancea and conducted analyses to characterize its genetic diversity, population evolution, and rewiring of volatile metabolites. The natural variation effect exerted significant pressure on A. lancea from different geographic locations, resulting in genetic differentiation among three groups. Correlation analysis of metabolites in A. lancea revealed significant natural variations of terpenoids, heterocyclic compounds, ketones, and esters. We also found that 427 metabolites displayed noteworthy divergence due to directional selection. Additionally, our genome-wide association studies on the metabolome for medicinal quality traits identified several candidate genes, such as AlZFP706 and AlAAHY1, exhibiting significant correlations with atractylodin and hinesol levels, respectively. Overall, this study provides an intricate genomic resource for A. lancea, thereby expanding our understanding of the effect of natural variation on metabolites and facilitating the genetic improvement of its medicinal properties.
ABSTRACT
Rubus chingii and R. chingii var. suavissimus are unique dual-purpose plant resources, with significant nutraceutical, pharmaceutical, and economic value, as well as promising prospects for further development. To investigate the genetic structure and evolutionary characteristics of these two varieties, this study conducted plastome sequencing using the Illumina HiSeq XTen sequencing platform. Subsequently, the study performed assembly, annotation, and characterization of the genomes, followed by a comparative plastome and phylogenetic analysis using bioinformatics techniques. The results revealed that the plastomes of R. chingii and R. chingii var. suavissimus exhibited a tetrad structure, comprising a large single-copy region(LSC), a small single-copy region(SSC), and two inverted repeat regions(IRs). The study identified a total of 56 simple sequence repeats(SSRs) after comparative analysis, predominantly consisting of A and T. Furthermore, the structure of the IR boundary genes in both varieties was found to be highly conserved, with only minor nucleotide variations. Additionally, the study identified three highly variable regions: rps16-trnQ-psbK, trnR-atpA, and trnT-trnL, which held promise as potential identification marks for further development and utilization. Phylogenetic analysis results obtained by the maximum likelihood and Bayesian inference methods demonstrated a close clustering of R. chingii and R. chingii var. suavissimus(100% support), with their closest relatives being R. trianthus. This study, focusing on plastome-level genetic distinctions between these two varieties, lays a foundation for future species protection, development, and utilization.
Subject(s)
Rubus , Phylogeny , Bayes Theorem , Biological Evolution , Microsatellite RepeatsABSTRACT
BACKGROUND: The sustainable supply of medicinal plants is important, and cultivating and domesticating them has been suggested as an optimal strategy. However, this can lead to a loss of genetic diversity. Tripterygium wilfordii Hook. f. is a medicinal plant commonly used in traditional Chinese medicine, but its wild populations are dwindling due to excessive harvesting. To protect the species and meet the increasing demand, it is urgent to cultivate it on a large scale. However, distinguishing between T. wilfordii and T. hypoglaucum, two similar species with different medicinal properties, is challenging. Therefore, it is crucial to understand the genetic diversity and population structure of these species for their sustainable utilization. RESULTS: In this study, we investigated the genetic diversity and population structure of the two traditional medicinal semiwoody vines plant species, Tripterygium wilfordii and T. hypoglaucum, including wild and cultivated populations using chloroplast DNA (cpDNA) sequences and microsatellite loci. Our results indicated that the two species maintain a high level of genetic divergence, indicating possible genetic bases for the different contents of bioactive compounds of the two species. T. wilfordii showed lower genetic diversity and less subdivided population structures of both markers than T. hypoglaucum. The potential factors in shaping these interesting differences might be differentiated pollen-to-seed migration rates, interbreeding, and history of population divergence. Analyses of cpDNA and microsatellite loci supported that the two species are genetically distinct entities. In addition, a significant reduction of genetic diversity was observed for cultivated populations of the two species, which mainly resulted from the small initial population size and propagated vegetative practice during their cultivation. CONCLUSION: Our findings indicate significant genetic divergence between T. wilfordii and T. hypoglaucum. The genetic diversity and population structure analyses provide important insights into the sustainable cultivation and utilization of these medicinal plants. Accurate identification and conservation efforts are necessary for both species to ensure the safety and effectiveness of crude drug use. Our study also highlighted the importance of combined analyses of different DNA markers in addressing population genetics of medicinal plants because of the contrasts of inheritance and rates of gene flow. Large-scale cultivation programs should consider preserving genetic diversity to enhance the long-term sustainability of T. wilfordii and T. hypoglaucum. Our study proposed that some populations showed higher genetic diversity and distinctness, which can be considered with priority for conservation and as the sources for future breeding and genetic improvement.
Subject(s)
Celastraceae , Plants, Medicinal , Tripterygium/genetics , Tripterygium/chemistry , Celastraceae/genetics , Plant Breeding , Genetics, Population , Plants, Medicinal/genetics , DNA, Chloroplast/genetics , Genetic VariationABSTRACT
A previous 1H-NMR method allowed the quantification of ephedrine alkaloids; however, there were some disadvantages. The cyclized derivatives resulted from the impurities of diethyl ether were identified and benzene was selected as the better extraction solvent. The locations of ephedrine alkaloids were confirmed with 2D NMR. Therefore, a specific 1H-NMR method has been modified for the quantification of ephedrine alkaloids. Accordingly, twenty Ephedrae Herba samples could be classified into three classes: (I) E. sinica-like species; (II) E. intermedia-like species; (III) others (lower alkaloid contents). The results indicated that ephedrine and pseudoephedrine are the major alkaloids in Ephedra plants, but the concentrations vary greatly determined by the plant species and the collection locations.
Subject(s)
Alkaloids , Ephedra , Ephedrine , Proton Magnetic Resonance Spectroscopy , Pseudoephedrine , Ephedrine/analysis , Pseudoephedrine/analysis , Ephedra/chemistry , Alkaloids/analysis , Proton Magnetic Resonance Spectroscopy/methodsABSTRACT
BACKGROUND: Leonurus japonicus, a significant medicinal plant known for its therapeutic effects on gynecological and cardiovascular diseases, has genetic diversity that forms the basis for germplasm preservation and utilization in medicine. Despite its economic value, limited research has focused on its genetic diversity and divergence. RESULTS: The avg. nucleotide diversity of 59 accessions from China were 0.00029 and hotspot regions in petN-psbM and rpl32-trnL(UAG) spacers, which can be used for genotype discrimination. These accessions divided into four clades with significant divergence. The four subclades, which split at approximately 7.36 Ma, were likely influenced by the Hengduan Mountains uplift and global temperature drop. The initial divergence gave rise to Clade D, with a crown age estimated at 4.27 Ma, followed by Clade C, with a crown age estimated at 3.39 Ma. The four clades were not showed a clear spatial distribution. Suitable climatic conditions for the species were identified, including warmest quarter precipitation 433.20 mm ~ 1,524.07 mm, driest month precipitation > 12.06 mm, and coldest month min temp > -4.34 °C. The high suitability distribution showed contraction in LIG to LGM, followed by expansion from LGM to present. The Hengduan Mountains acted as a glacial refuge for the species during climate changes. CONCLUSIONS: Our findings reflected a clear phylogenetic relationships and divergence within species L. japonicus and the identified hotspot regions could facilitate the genotype discrimination. The divergence time estimation and suitable area simulation revealed evolution dynamics of this species and may propose conservation suggestions and exploitation approaches in the future.
Subject(s)
Leonurus , Biodiversity , Phylogeny , Temperature , China , Genetic VariationABSTRACT
The genus Coptis belongs to the Ranunculaceae family, containing 15 recognized species highly diverse in morphology. It is a conspicuous taxon with special evolutionary position, distribution pattern and medicinal value, which makes it to be of great research and conservation significance. In order to better understand the evolutionary dynamics of Coptis and promote more practical conservation measures, we performed plastome sequencing and used the sequencing data in combination with worldwide occurrence data of Coptis to estimate genetic diversity and divergence times, rebuild biogeographic history and predict its potential suitable distribution area. The average nucleotide diversity of Coptis was 0.0067 and the hotspot regions with the highest hypermutation levels were located in the ycf1 gene. Coptis is most likely to have originated in North America and Japanese archipelago and has a typical Eastern Asian and North American disjunct distribution pattern, while the species diversity center is located in Mid-West China and Japan. The crown age of the genus is estimated at around 8.49 Mya. The most suitable climatic conditions for Coptis were as follows: precipitation of driest quarter > 25.5 mm, annual precipitation > 844.9 mm and annual mean temperature -3.1 to 19 °C. The global and China suitable area shows an upward trend in the future when emission of greenhouse gases is well controlled, but the area, especially in China, decreases significantly without greenhouse gas policy interventions. The results of this study provide a comprehensive insight into the Coptis evolutionary dynamics and will facilitate future conservation efforts.
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Root rot has been a major problem for cultivated populations of Coptis chinensis var. chinensis in recent years. C. chinensis var. brevisepala, the closest wild relative of C. chinensis var. chinensis, has a scattered distribution across southwestern China and is an important wild resource. Genetic diversity is associated with greater evolutionary potential and resilience of species or populations and is important for the breeding and conservation of species. Here, we conducted multiplexed massively parallel sequencing of the plastomes of 227 accessions of wild and cultivated C. chinensis using 111 marker pairs to study patterns of genetic diversity, population structure, and phylogeography among wild and cultivated C. chinensis populations. Wild and cultivated resources diverged approximately 2.83 Mya. The cultivated resources experienced a severe genetic bottleneck and possess highly mixed germplasm. However, high genetic diversity has been retained in the wild resources, and subpopulations in different locations differed in genotype composition. The significant divergence in the genetic diversity of wild and cultivated resources indicates that they require different conservation strategies. Wild resources require in situ conservation strategies aiming to expand population sizes while maintaining levels of genetic diversity; by contrast, germplasm resource nurseries with genotypes of cultivated resources and planned distribution measures are needed for the conservation of cultivated resources to prevent cultivated populations from undergoing severe genetic bottlenecks. The results of this study provide comprehensive insights into the genetic diversity, population structure, and phylogeography of C. chinensis and will facilitate future breeding and conservation efforts.
ABSTRACT
The internationalization of traditional Chinese medicine(TCM) is one of the strategic development objectives in China, which has been incorporated into the national strategy as an important part of the Belt and Road Initiative development strategy. As the basis and prerequisite of TCM development, Chinese materia medica(CMM) has a direct impact on the internationalization of TCM. The International Organization for Standardization(ISO) is a global organization composed of national standardization bodies, and the ISO standards impact the world's economy, trade, communication and cooperation. Based on a brief introduction to ISO/Traditional Chinese Medicine Technical Committee(ISO/TC 249), this study elaborates the necessity of establishing ISO standards for CMM and analyzes the current status and challenges faced by the formulation of international standards for CMM. Finally, this study puts forward the development strategy of international standards for CMM. Specifically, efforts should be made to develop top-level design with international market demands as the guidance and improve the quality of standards to accelerate the transformation of domestic high-quality standards into international standards. Moreover, measures should be taken to give full play to the positive role of enterprises in the formulation of standards, vigorously cultivate compound talents for international standardization of TCM, and constantly strengthen international cooperation. The experience and thinking are of guiding significance for the scientific, efficient and reasonable formulation of high-quality ISO standards for CMM in the future.
Subject(s)
Drugs, Chinese Herbal , Materia Medica , China , Humans , Medicine, Chinese Traditional , Reference StandardsABSTRACT
Ligustri Lucidi Fructus, the sun-dried mature fruit of Ligustrum lucidum, is cool, plain, sweet, and bitter, which can be used as both food and medicine, with the effects of improving vision, blacking hair, and tonifying liver and kidney. It takes effect slowly. However, little is known about the genetic information of the medicinal plant and it is still a challenge to distinguish Ligustrum species. In this study, the complete chloroplast genome of L. lucidum was obtained by genome skimming and then compared with that of five other Ligustrum species, which had been reported. This study aims to evaluate the interspecific variation of chloroplast genome within the genus and develop molecular markers for species identification of the genus. The result showed that the chloroplast genome of L. lucidum was 162 162 bp with a circular quadripartite structure of two single-copy regions separated by a pair of inverted repeats. The Ligustrum chloroplast genomes were conserved with small interspecific difference. Comparative analysis of six Ligustrum chloroplast genomes revealed three variable regions(rbcL-accD, ycf1a, and ycf1b), and ycf1a and ycf1b can be used as the species-specific DNA barcode for Ligustrum. Phylogeny analysis provided the best resolution of Ligustrum and supported that L. lucidum was sister to L. gracile. This study clarified the genetic diversity of L. lucidum from provenance, which can serve as a reference for further analysis of pharmacological differences and breeding of excellent varieties with stable drug effects.
Subject(s)
Genome, Chloroplast , Ligustrum , Fruit , Ligustrum/chemistry , Ligustrum/genetics , Phylogeny , Plant BreedingABSTRACT
Bactericera gobica is the major pest of Goji berry plants and causes severe damage. Psyllids mainly use the antennal sensilla to recognize olfactory cues necessary to find host plants and mates. However, the structure and function of the antenna and the antennal sensilla of B. gobica remains previously unexplored. Here, we identify the external and internal morphology of the antennal sensilla of B. gobica using both scanning electron microscopy (SEM) and transmission electron microscopy (TEM). We found seven types of sensilla on the filiform antennae, including apical setae (LAS, SAS), sensilla basiconica (SB1, SB2), sensilla campaniform (SCA), sensilla chaetica (ChS1, ChS2), cavity sensilla (CvS1, CvS2), antennal rhinaria (AR1, AR2), and sensilla trichodea (ST). Five of these sensilla types-apical setae, sensilla basiconica, sensilla chaetica, cavity sensilla, and antennal rhinaria-may have olfactory functions based on their porous surfaces and internal dendritic outer segments (DOS). We also found several differences between the two sexes of B. gobica in the sensilla array and internal structure. ChS and DOS in the protrusions of AR were more abundant in males than females. Altogether, we comprehensively revealed the fine structure and probable function of B. gobica antennae and identified differences in the distribution and structure between psyllid sexes. Our findings provide important insights for future studies on defining the olfactory function of psyllid antenna using electrophysiological methods.
Subject(s)
Hemiptera , Sensilla , Animals , Female , Male , Sensilla/anatomy & histology , Sex Characteristics , Hemiptera/ultrastructure , Electrons , Microscopy, Electron, Transmission , Microscopy, Electron, ScanningABSTRACT
Coptishuanjiangensis, a new species of Ranunculaceae distributed in the valleys of Jiuwanshan National Natural Reserve in Huanjiang county (Guangxi, China), is described and illustrated for the first time based on morphological and plastome sequences data. It differs from C.chinensis, C.deltoidei and C.omeiensis mainly by having notably longer petiole, scape, bigger leaf blade with lobes obviously remote and robust rhizomes without stolons. Phylogenetic analyses support that C.huanjiangensis is sister to C.omeiensis and C.deltoidei.
ABSTRACT
Leonurus cardiaca has a long history of use in western herbal medicine and is applied for the treatment of gynaecological conditions, anxiety, and heart diseases. Because of its botanical relationship to the primary Chinese species, L. japonicus, and extensive medical indications that go beyond the traditional indications for the Chinese species, it is a promising medicinal resource. Therefore, the features of genetic diversity and variability in the species have been prioritized. To explore these issues, we sequenced the chloroplast genomes of 22 accessions of L. cardiaca from different geographical locations worldwide using high-throughput sequencing. The results indicate that L. cardiaca has a typical quadripartite structure and range from 1,51,236 bp to 1,51,831 bp in size, forming eight haplotypes. The genomes all contain 114 distinct genes, including 80 protein-coding genes, 30 transfer RNA genes and four ribosomal RNA genes. Comparative analysis showed abundant diversity of single nucleotide polymorphisms (SNPs), indels, simple sequence repeats (SSRs) in 22 accessions. Codon usage showed highly similar results for L. cardiaca species. The phylogenetic and network analysis indicated 22 accessions forming four clades that were partly related to the geographical distribution. In summary, our study highlights the advantage of chloroplast genome with large data sets in intraspecific diversity evaluation and provides a new tool to facilitate medicinal plant conservation and domestication.
ABSTRACT
Coptidis Rhizoma is a common Chinese medicinal in clinical practice,with the effects of clearing heat,drying dampness,purging fire,and removing toxin. All the medicinal plants of Coptis can be used for clinical treatment,but some species are endangered due to resource destruction and difficulty in planting. The dominant medicinal components in Coptidis Rhizoma are isoquinoline alkaloids. There are various methods for the analysis and detection of alkaloids,such as LC-MS,HPLC,and TLC,among which LC-MS is the most widely applied. Different plants of Coptis vary in the kind and content of alkaloids. C. chinensis,C. deltoidea,C. teeta,C. chinensis var. brevisepala,C. omeiensis,C. quinquefolia,and C. quinquesecta mainly contain berberine,palmatine,coptisine,jatrorrhizine,and columbamine,five effective alkaloid components. Plant isoquinoline alkaloids( PIAs) have strong pharmacological activity but are difficult to prepare. The application of synthetic biology of PIAs will be helpful for the clinical application of PIAs. This paper reviews the research progress on biological resources of Coptis species and structures of alkaloids as well as analysis methods and synthetic biology for isoquinoline alkaloids in the medicinal plants of Coptis in recent years,which will facilitate the protection of Coptis medicinal resources and the application and development of alkaloids.
Subject(s)
Alkaloids , Berberine Alkaloids , Berberine , Coptis , Drugs, Chinese Herbal , Isoquinolines , RhizomeABSTRACT
According to the records of Chinese materia medica,Coptis chinensis var. brevisepala is an authentic Chinese medicinal plant highly recommended by ancient physicians since its rhizome is like a string of beads and has a good medicinal value. However,its medicinal components and values remain to be studied as it is endangered because of overexploitation. Therefore,this study aims to quantitatively determine its effective components based on UPLC-QTOF-MS,and to compare the contents of isoquinoline alkaloids in C.chinensis var. brevisepala with those in other Coptis species. Meanwhile,molecular methods accurately identified 12 batches of C. chinensis var. brevisepala,9 batches of C. chinensis,4 batches of C. deltoidea,and 1 batch of C. teeta. Gradient elution was performed with Waters CORTECS C18 column( 4. 6 mm× 150 mm,2. 7 µm) and the mobile phase acetonitrile-water with 0. 4% formic acid. Mass spectrometry was conducted in ESI positive mode. The quantitative results showed that 8 main alkaloids had a good linear relationship within the concentration range( R~2>0. 996),with the recovery rate of 95. 18%-105. 0% and the RSD of 0. 28%-3. 7%. Compared with that of other Coptis species,the rhizome of C. chinensis var. brevisepala had the highest contents of berberine and columbamine. The total content of the 8 alkaloids in C. chinensis var. brevisepala was similar to that in C. chinensis but higher than that of the other two species. PCA was performed to compare the alkaloids among the 4 species. Besides,the 8 alkaloids were evaluated in different parts of C. chinensis var. brevisepala. The results indicate that this method is reliable and efficient and can provide a reference for the quality research.
Subject(s)
Alkaloids , Berberine Alkaloids , Coptis , Drugs, Chinese Herbal , Plants, Medicinal , China , Drugs, Chinese Herbal/analysisABSTRACT
Nitrogen fertilizer has been the long-lasting crucial component in cultivation of Chinese materia medica(CMM) and crops for its profound effects on enhancing the productivity. In consideration of its role in better production, intensive and excessive application of N fertilizer is often found in CMM cultivation. Therefore, firstly, this review summarized various concentrations of N application with regards to different CMM and districts from the literatures published in the last two decades. The recommended concentration of nitrogen application of forty seven CMM species were covered in this review. We found that the optimum rates of nitrogen fertili-zer for different medicinal plants species were varied in the range between 0-1 035.55 kg·hm~(-2). Most of the optimum rates of nitrogen fertilizer for CMM in published researches fell between 100-199 kg·hm~(-2). The optimum rate of nitrogen fertilizer is not only related to amount of nitrogen required for different medicinal plants but also to soil fertilities of different fields. In addition, we outlined the diffe-rent effects of proper and excessive nitrogen deposition on yield of CMM. Proper nitrogen deposition benefits the yield of CMM, howe-ver, excessive nitrogen use accounts for a decrease in CMM yield. We elucidated that nutritional content, water use efficiencies, and photosynthesis capacity were major influencing factors. Researches showed that proper nitrogen fertilizer could promote the water use efficiencies of plants and boost photosynthesis. Consequently, the yield of CMM can be enhanced after nitrogen deposition. However, negative effects of nitrogen fertilizer were also found on plant including producing toxic substances to the soil and causing severe pest damages. Lastly we analyzed the impact of N fertilizer application on secondary metabolites which accounts for a large part of active pharmaceutical ingredients of CMM. It usually caused an increase in nitrogen-containing secondary metabolites content and a decrease in non-nitrogen-containing secondary metabolites content respectively. The potential underlying mechanisms are the different synthetic pathways of these metabolites and the plant nutritional status. Synthesis of non-nitrogen-containing secondary metabolites like phenols can be inhibited after nitrogen application because of the competition of the same precursor substances between metabolites synthesis and plant growth. To sum up, impacts and mechanisms of nitrogen fertilizer on yield and quality enhancement of CMM were discussed in this review. Negative effects of excessive nitrogen application on CMM should be paid special attention in CMM cultivation and prescription fertilization based on the field soil quality is strongly recommended. Overall, this review aims to provides insights on improving the proper application of N fertilizer in the cultivation of CMM.
Subject(s)
Materia Medica , Nitrogen , Agriculture , China , Fertilizers , Nitrogen/analysis , SoilABSTRACT
Nitrogen fertilizers play an important role in the regulation of plant stress resistance. Impacts of nitrogen fertilizers on abiotic stress resistance and biotic stress resistance of Chinese materia medica(CMM) were summarized in this study. Adequate nitrogen application improves the abiotic stress resistance and weed resistance of CMM, however adverse effect appears when excess nitrogen is used. Generally, pest resistance decreases along with nitrogen deposition, while effects of nitrogen application on disease resistance vary with different diseases. Mechanisms underlying the impact of nitrogen fertilizers on plant stress resistance were also elucidated in this study from three aspects including physical defense mechanisms, biochemistry mechanisms and molecular defense mechanisms. Nitrogen availability modulates physical barrier of CMM like plant growth, formation of lignin and wax cuticle, and density of stomata. Growth of CMM promoted by nitrogen fertilizer may cause some decrease in pest resistance of CMM due to an increase in hiding places for pest along with plant growth. High ambient humidity caused by excessive plant growth facilitates the growth and development of CMM pathogen. Nitrogen application can also interfere with the accumulation of lignin in CMM which makes CMM more vulnerable to pest and pathogen attack. Stomatal closing delays due to nitrogen application is also a causal factor of increasing pathogen infection after nitrogen deposition. Biochemical defenses of plants are mainly achieved through nutrient elements, secondary metabolites, defense-related enzymes and proteins. Nutritional level of CMM and various antioxidant enzymes and resistance-related protein activities are elevated along with nitrogen deposition. These antioxidant enzymes can reduce the damage of reactive oxygen species content produced by plant in response to adversity and therefore enhance stress resistance of CMM. Researches showed that nitrogen application could also cause an increase in nitrogen-containing secondary metabolites content and a decrease in non-nitrogen-containing secondary metabolites content respectively. Nitrogen-mediated molecular defense mechanisms includes multiple plant hormones and nitric oxide signals. Plant hormones related to plant defense like salicylic acid, jasmonic acid and abscisic acid can be modulated by nitrogen application. Negative effect of nitrogen deposition was found on salicylic acid accumulation and the expression of related plant disease resistance genes. However, jasmonic acid level can be elevated by nitrogen. Nitric oxide signals constitute an important part of nitrogen mediated defense mechanisms. Nitric oxide signaling is related to many aspects of plant immunity. The roles of nitrogen fertilizers in CMM stress resistance are complex and may vary with different CMM varieties and environments. Further studies are urgently needed to provide a comprehensive understanding of how to improve stress resistance of CMM by using fertilizers.
Subject(s)
Materia Medica , Abscisic Acid , China , Nitrogen , Plant Growth RegulatorsABSTRACT
BACKGROUND: Most Distylium species are endangered. Distylium species mostly display homoplasy in their flowers and fruits, and are classified primarily based on leaf morphology. However, leaf size, shape, and serration vary tremendously making it difficult to use those characters to identify most species and a significant challenge to address the taxonomy of Distylium. To infer robust relationships and develop variable markers to identify Distylium species, we sequenced most of the Distylium species chloroplast genomes. RESULTS: The Distylium chloroplast genome size was 159,041-159,127 bp and encoded 80 protein-coding, 30 transfer RNAs, and 4 ribosomal RNA genes. There was a conserved gene order and a typical quadripartite structure. Phylogenomic analysis based on whole chloroplast genome sequences yielded a highly resolved phylogenetic tree and formed a monophyletic group containing four Distylium clades. A dating analysis suggested that Distylium originated in the Oligocene (34.39 Ma) and diversified within approximately 1 Ma. The evidence shows that Distylium is a rapidly radiating group. Four highly variable markers, matK-trnK, ndhC-trnV, ycf1, and trnT-trnL, and 74 polymorphic simple sequence repeats were discovered in the Distylium plastomes. CONCLUSIONS: The plastome sequences had sufficient polymorphic information to resolve phylogenetic relationships and identify Distylium species accurately.
Subject(s)
Genome, Chloroplast , Hamamelidaceae , Chloroplasts/genetics , Evolution, Molecular , PhylogenyABSTRACT
Emergency of nanoparticulate drug delivery systems has improved the target, bioavailability, and curative effect of traditional Chinese medicine (TCM). However, the application of nano-preparation has been limited owing to the low content of active ingredients in part TCM. MicroRNAs (miRNAs) regulate plant growth, development, and response to environmental stresses at post-transcriptional regulation level by cleavage or translational inhibition. The molecular functions of miRNAs playing a role in synthesizing active comportments at medicinal plants have been widely researched. Dendrobium nobile is a perennial herb in the orchidaceae family. D. nobile protocorm can produce plant-specific metabolites at a short period. Therefore, it is a good substitute for producing metabolites. To understand the functions of miRNAs in D. nobile protocorm, Illumina sequencing of D. nobile protocorm (Dnp), D. officinale protocorm (Dcp), and D. nobile leaf (Dnl) were carried out. A total of 439, 412, and 432 miRNAs were identified from Dnp, Dcp, and Dnl, respectively. Some specific miRNAs were identified among them. Through combing GO and KEGG function annotation, miRNAs mainly involved metabolic pathways, plant hormone signal transduction, biological regulation, and protein binding. Acetyl-CoA acetyltransferase (AACT), mevalonate kinase (MK), 1-deoxy-D-xylulose 5-phosphate reductoisomerase (DXR), and 2-C-methyl-D-erythritol 4-phosphate cytidylyltransferase (HDS), synthesizing basic precursor isoprene pyrophosphate (IPP) in terpenoid backbone biosynthesis pathway, were predicted as potential targets of 6 different miRNAs. Twenty-six miRNAs participated in auxin, cytokinin, abscisic acid, jasmonic acid, and salicylic acid signal transduction pathway. This report provided valuable candidate genes in Dnp involved in terpenoid biosynthesis and plant hormone signal transduction pathway. At the same time, it can help accelerate the use of dendrobine into nano preparation.
Subject(s)
Alkaloids , Dendrobium , MicroRNAs , Dendrobium/genetics , High-Throughput Nucleotide Sequencing , MicroRNAs/geneticsABSTRACT
Sargentodoxa cuneata is used as traditional Chinese medicine. In this study, we report its complete chloroplast genome by Illumina pair-end sequencing. The total chloroplast (cp) genome size was 158,094 bp in length, containing a pair of inverted repeats of 26,132 bp, separated by large single-copy and small single-copy regions of 86,508 bp and 19,322 bp, respectively. The chloroplast genome of S. cuneata encodes 113 different genes, including 79 protein-coding genes, 30 transfer RNAs, and 4 ribosomal RNAs. A total of 84 perfect chloroplast microsatellites were analyzed in the S. cuneata. The majority of the SSRs in this chloroplast genome are mononucleotides (66.67%). The reconstructed phylogeny revealed that S. cuneata was sister to the remaining Lardizabalaceae.
ABSTRACT
BACKGROUND: Atractylodes DC is the basic original plant of the widely used herbal medicines "Baizhu" and "Cangzhu" and an endemic genus in East Asia. Species within the genus have minor morphological differences, and the universal DNA barcodes cannot clearly distinguish the systemic relationship or identify the species of the genus. In order to solve these question, we sequenced the chloroplast genomes of all species of Atractylodes using high-throughput sequencing. RESULTS: The results indicate that the chloroplast genome of Atractylodes has a typical quadripartite structure and ranges from 152,294 bp (A. carlinoides) to 153,261 bp (A. macrocephala) in size. The genome of all species contains 113 genes, including 79 protein-coding genes, 30 transfer RNA genes and four ribosomal RNA genes. Four hotspots, rpl22-rps19-rpl2, psbM-trnD, trnR-trnT(GGU), and trnT(UGU)-trnL, and a total of 42-47 simple sequence repeats (SSR) were identified as the most promising potentially variable makers for species delimitation and population genetic studies. Phylogenetic analyses of the whole chloroplast genomes indicate that Atractylodes is a clade within the tribe Cynareae; Atractylodes species form a monophyly that clearly reflects the relationship within the genus. CONCLUSIONS: Our study included investigations of the sequences and structural genomic variations, phylogenetics and mutation dynamics of Atractylodes chloroplast genomes and will facilitate future studies in population genetics, taxonomy and species identification.