Comparative transcriptome analysis reveals candidate genes related to the sex differentiation of Schisandra chinensis.

Schisandra chinensis is a monoecious plant with unisex flowers. The fruit of S. chinensis is of high medical with economic value. The yield of S. chinensis fruit is related to the ratio of its female and male flowers. However, there is little research on its floral development and sex differentiation. To elucidate the possible mechanism for the sex differentiation of S. chinensis, we collected 18 samples of female and male flowers from three developmental stages and performed a comparative RNA-seq analysis aimed at identifying differentially expressed genes (DEGs) that may be related to sex differentiation. The results showed 936, 7179, and 6890 differentially expressed genes between female and male flowers at three developmental stages, respectively, and 466 candidate genes may play roles in sex differentiation. KEGG analysis showed genes involved in the flavonoid biosynthesis pathway and DNA replication pathway were essential for the development of female flowers. 51 MADS-box genes and 10 YABBY genes were identified in S. chinensis. The DEGs analysis indicated that MADS-box and YABBY genes were strongly related to the sex determination of S. chinensis. RT-qPCR confirmed the RNA-seq results of 20 differentially expressed genes, including three male-biased genes and 17 female-biased genes. A possible regulatory model of sex differentiation in S. chinensis was proposed according to our results. This study helps reveal the sex-differentiation mechanism of S. chinensis and lays the foundation for regulating the male-female ratio of S. chinensis in the future.

[Anti-inflammatory active component in raw materials of Ligustici Rhizoma et Radix based on spectrum-effect relationship].

The present study investigated the correlation of UPLC fingerprints of raw materials of Ligustici Rhizoma et Radix samples with the anti-inflammatory effect and explored the pharmacodynamic material basis for the anti-inflammatory activity. UPLC fingerprints of 18 batches of raw materials of Ligustici Rhizoma et Radix samples were established for the determination of the content of eight components. The toe swelling rate and the content of IL-1ß, IL-6, and PGE2 in rats with toe inflammation induced by carrageenin were measured. Canonical correlation analysis was used to study the spectrum-effect relationship. Cluster analysis indicated that chemical components of Ligusticum sinense and L. jeholense were similar. Methanol extracts of L. sinense, L. jeholense, and Conioselinum vaginatum significantly reduced the toe swelling rate and the content of IL-1ß, IL-6 and PGE2 in swollen tissues. The anti-inflammatory effect of C. vaginatum was weaker than that of L. sinense and L. jeholense. The results of spectrum-effect relationship indicated that there was an obvious correlation between chemical components and pharmacodynamic indexes. In UPLC fingerprints, compounds 1, 3(chlorogenic acid), 4(cryptochlorogenic acid), 5, 6(ferulic acid), 7(isochlorogenic acid B), 9, 11, 13, 15, 16, 17, 18(coniferyl ferulate), 19, 20(N-butylphthalide), 21, 22, and 23 were significantly correlated with anti-inflammation, among which compounds 5, 11, 13, 15, 17, 21, and 23 had negative correlation. This study screened out the effective components with anti-inflammatory activity in raw materials of Ligustici Rhizoma et Radix, which was of great significance to improve the quality evaluation system of raw materials of Ligustici Rhizoma et Radix.

Molecular Structure and Phylogenetic Analyses of the Complete Chloroplast Genomes of Three Medicinal Plants Conioselinum vaginatum, Ligusticum sinense, and Ligusticum jeholense.

Most plants of Ligusticum have an important medicinal and economic value with a long history, Ligusticum sinense and L. jeholense ("Gaoben") has long been used in traditional Chinese medicine for the treatment of carminative, dispelling cold, dehumidification, and analgesia. While in the market Conioselinum vaginatum (Xinjiang Gaoben) is substitution for Gaoben, and occupies a higher market share. These three Gaoben-related medicinal materials are similar in morphology, and are difficult to distinguish from each other by the commonly used DNA barcodes. The chloroplast genome has been widely used for molecular markers, evolutionary biology, and barcoding identification. In this study, the complete chloroplast genome sequences of C. vaginatum, L. sinense, and L. jeholense were reported. The results showed that the complete chloroplast genomes of these three species have typical quadripartite structures, which were comprised of 148,664, 148,539, and 148,497 bp. A total of 114 genes were identified, including 81 protein-coding genes (PCGs), 29 tRNA genes, and four rRNA genes. Our study indicated that highly variable region ycf2-trnL and accD-ycf4 that can be used as specific DNA barcodes to distinguish and identify C. vaginatum, L. sinense, and L. jeholense. In addition, phylogenetic study showed that C. vaginatum nested in Ligusticum and as a sister group of L. sinense and L. jeholense, which suggested these two genera are both in need of revision. This study offer valuable information for future research in the identification of Gaoben-related medicinal materials and will benefit for further phylogenetic study of Apiaceae.

[Research progress in DIR gene of lignan biosynthesis in medicinal plants].

The active components, mainly derived from secondary metabolites of medicinal plants, are the material basis for the efficacy of medicinal plants. Lignans, the secondary metabolites in plants with high bioactivity, are widely distributed in a variety of plant species, and their antiviral, antitumor, antibacterial, and antioxidant activities have been proved in clinical practice. Generally, lignans are diverse in structures with many chiral centers, and most of them are optically active. The biosynthesis of lignans depends on the oxidative coupling reaction through site selection and stereo selection, which impedes synthesized lignans to form racemates, but makes them in a three-dimensional configuration. Dirigent protein(DIR) plays an important role in guiding location selection and stereo selection of lignans in biosynthesis. In vitro studies on lignan biosynthesis have shown that racemic end products are obtained in the absence of DIR proteins, while the products in a three-dimensional configuration can be yielded in the presence of DIR proteins, indicating that DIR proteins play an asymmetric role in the biosynthesis of plant secondary metabolites. The present study reviewed the biolo-gical significance of DIR protein, the cloning of DIR gene, gene structure, catalytic mechanism, and the research progress in Isatis indigotica, Eucommia ulmoides, Forsythia suspensa, Salvia miltiorrhiza, Panax pseudoginseng var. notoginseng, and Schisandra chinensis, which provides a reference for the follow-up research of DIR gene.

Plastid phylogenomics provides novel insights into the infrafamilial relationship of Polypodiaceae.

The polygrammoids (Polypodiaceae) are the most species-rich and diversified epiphytic fern lineages, and hold an important role to understand the deep diverging events and rapid adaptation to changing environments in the plant tree of life. Despite progress in the phylogeny of this group of ferns in previous multilocus phylogenetic studies, uncertainty remains especially in backbone relationships among closely related clades, and the phylogenetic placement of recalcitrant species or lineages. Here, we investigated the deep phylogenetic relationships within Polypodiaceae by sampling all major lineages and using 81 plastid genomes (plastomes), of which 70 plastomes were newly sequenced with high-throughput sequencing technology. Based on parsimony, maximum-likelihood, Bayesian and multispecies coalescent analyses of genome skimming data, we achieved a better resolution of the backbone phylogeny of Polypodiaceae. Using simulated data matrices, we detected that potential phylogenetic artefacts, such as long-branch attraction and insufficient taxonomic sampling, may have a confounding impact on the incongruence of phylogenetic inferences. Furthermore, our phylogenetic analyses offer greater resolution than previous multilocus studies, providing a robust framework for future phylogenetic implications on the subfamilial taxonomy of Polypodiaceae. Our phylogenomic study not only demonstrates the advantage of a character-rich plastome dataset for resolving the recalcitrant lineages that have undergone rapid radiation, but also sheds new light on integrative explorations understanding the evolutionary history of large fern groups in the genomic era.

[Identification and characterization of DIR gene family in Schisandra chinensis].

Dirigent(DIR) proteins are involved in the biosynthesis of lignin, lignans, and gossypol in plants and respond to biotic and abiotic stresses. Based on the full-length transcriptome of Schisandra chinensis, bioinformatics methods were used to preliminarily identify the DIR gene family and analyze the physico-chemical properties, subcellular localization, conserved motifs, phylogeny, and expression patterns of the proteins. The results showed that a total of 34 DIR genes were screened and the encoded proteins were 156-387 aa. The physico-chemical properties of the proteins were different and the secondary structure was mainly random coil. Half of the DIR proteins were located in chloroplast, while the others in extracellular region, endoplasmic reticulum, cytoplasm, etc. Phylogenetic analysis of DIR proteins from S. chinensis and the other 8 species such as Arabidopsis thaliana, Oryza sativa, and Glycine max demonstrated that all DIR proteins were clustered into 5 subfamilies and that DIR proteins from S. chinensis were in 4 subfamilies. DIR-a subfamily has the unique structure of 8 ß-sheets, as verified by multiple sequence alignment. Finally, through the analysis of the transcriptome of S. chinensis fruit at different development stages, the expression pattern of DIR was clarified. Combined with the accumulation of lignans in fruits at different stages, DIR might be related to the synthesis of lignans in S. chinensis. This study lays a theoretical basis for exploring the biological functions of DIR genes and elucidating the biosynthesis pathway of lignans in S. chinensis.

Genome sizes of four important medicinal species in Kadsura by flow cytometry.

Objective: Dianjixueteng is a geoherb in Yunnan Province, the source plant of which is Kadsura interior. However, the formation of this geoherb is not clear in genetic mechanism, in which genome size is the first step that should be known on the genomic level. In this study we aimed to estimate the genome sizes of source plants of K. interior and three related herbs K. heteroclita, K. longipedunculata, and K. coccinea by flow cytometry (FCM) and make a comparison. Methods: The genome sizes of K. interior, K. heteroclita, K. longipedunculata and K. coccinea, i.e., the source plants of Dianjixueteng and its relative medicinal materials, were estimated by FCM. The nuclei of K. interior were isolated using modified LB01 buffer, for the rest species, by the Galbraith's buffer. Results: The genome sizes of K. interior, K. heteroclita, K. longipedunculata, and K. coccinea were 7.36, 7.12, 7.01, and 5.15 pg/1C, respectively. Genome size of K. interior had no significant variation with those of K. heteroclita and K. longipedunculata (P = 0.296), which was significantly larger than that of K. coccinea. Conclusion: Genome size can not distinguish K. interior from K. heteroclita and K. longipedunculata, but could distinguish them from K. coccinea, which lays the foundation for future studies on genetic mechanism of the geoherb formation.

[Molecular identification and efficacy analysis of herbs at Orussey Herbal Market, Phnom Penh, Cambodia].

Cambodia is rich in medicinal plant resources. One hundred and thirty-three medicinal material samples, including the hole herb, root, stem/branch, leaf, flower, fruit, seed, and resin, were collected from the Orussey Herbal Market in Phnom Penh, Cambodia, and then authenticated by ITS and psbA-trnH. A total of 46 samples were identified based on ITS sequences, belonging to 24 families, 40 genera, and 42 species. A total of 100 samples were identified by psbA-trnH sequences to belong to 42 families, 77 genera, and 84 species. A total of 103 samples were identified by two DNA barcodes. According to the morphological characteristics of the medicinal materials, 120 samples classified into 50 species, 86 genera, and 86 families were identified, and the majority of them were from Zingiberaceae, Fabaceae, and Acanthaceae. Such samples have been commonly used in traditional Cambodian medicine, Ayurvedic medicine, Unani medicine, traditional Chinese medicine, and ethnomedicine, but different medical systems focus on different functional aspects of the same medicinal material. The results of this study have demonstrated that DNA barcoding has a significant advantage in identifying herbal products, and this study has provided basic data for understanding the traditional medicinal materials used in Cambodia.

Molecular structure and phylogenetic analyses of the complete chloroplast genomes of three original species of Pyrrosiae Folium.

Pyrrosia petiolosa, Pyrrosia lingua and Pyrrosia sheareri are recorded as original plants of Pyrrosiae Folium (PF) and commonly used as Chinese herbal medicines. Due to the similar morphological features of PF and its adulterants, common DNA barcodes cannot accurately distinguish PF species. Knowledge of the chloroplast (cp) genome is widely used in species identification, molecular marker and phylogenetic analyses. Herein, we determined the complete cp genomes of three original species of PF via high-throughput sequencing technologies. The three cp genomes exhibited a typical quadripartite structure with sizes ranging from 158 165 to 163 026 bp. The cp genomes of P. petiolosa and P. lingua encoded 130 genes, whilst that of P. sheareri encoded 131 genes. The complete cp genomes were compared, and five highly divergent regions of petA-psbJ, matK-rps16, ndhC-trnM, psbM-petN and psaC-ndhE were screened as potential DNA barcodes for identification of Pyrrosia genus species. The phylogenetic tree we obtained indicated that P. petiolosa and P. lingua are clustered in a single clade and, thus, share a close relationship. This study provides invaluable information for further studies on the species identification, taxonomy and phylogeny of Pyrrosia genus species.

[Simultaneous determination of six major isosteroidal alkaloids in Beimu by UPLC-ELSD].

An UPLC method was established for the direct determination of six major bioactive isosteroidal alkaloids, namely peimisine, imperialine, sipeimine-3-D-glucoside, verticinone, verticine and hupehenine from the bulbus of Fritillaria(Beimu), a commonly used antitussive traditional Chinese medicinal(TCM) herb. An Acquity UPLC~(TM) CSH C_(18) column(2.1 mm×100 mm, 1.7 µm) was used for all analysis. The investigated six compounds were all separated with gradient mobile phase consisting of 0.02% diethylamine-water-methanol at a flow rate of 0.3 mL·min~(-1). The temperature of sample manager was set at 20 ℃. Drift tube temperature was 45 ℃, and spray parameter was 40% with injection volume of 1 µL. Then, the further quality assessment of Beimu was carried out by cluster analysis(CA) and principal component analysis(PCA). The investigated all had good linearity(r≥0.998 9) over the tested ranges. The method is simple, accurate and reproducible, and can be used for determining the content of six major bioactive isosteroidal alkaloids.

Comparing chloroplast genomes of traditional Chinese herbs Schisandra sphenanthera and S. chinensis.

Objective: Schisandra sphenanthera and S. chinensis are the two important medicinal plants that have long been used under the names of "Nan-Wuweizi" and "Wuweizi", respectively. The misuse of "Nan-Wuweizi" and "Wuweizi" in herbal medical products calls for an accurate method to distinguish these herbs. Chloroplast (cp) genomes have been widely used in species delimitation and phylogeny due to their uniparental inheritance and lower substitution rates than that of the nuclear genomes. To develop more efficient DNA markers for distinguishing S. sphenanthera, S. chinensis, and the related species, we sequenced the cp genome of S. sphenanthera and compared it to that of S. chinensis. Methods: The cp genome of S. sphenanthera was sequenced at the Illumina HiSeq platform, and the reference-guided mapping of contigs was obtained with a de novo assembly procedure. Then, comparative analyses of the cp genomes of S. sphenanthera and S. chinensis were carried out. Results: The cp genome of S. sphenanthera was 146 853 bp in length and consisted of a large single copy (LSC) region of 95 627 bp, a small single copy (SSC) region of 18 292 bp, and a pair of inverted repeats (IR) of 16 467 bp. GC content was 39.6%. A total of 126 functional genes were predicted, of which 113 genes were unique, including 79 protein-coding genes, 30 transfer RNA (tRNA) genes, and four ribosomal RNA (rRNA) genes. Five tRNA, four protein-coding genes, and all rRNA were duplicated in the IR regions. There were 18 intron-containing genes, including six tRNA genes and 12 protein-coding genes. In addition, 45 SSRs were detected. The whole cp genome of S. sphenanthera was 123 bp longer than that of S. chinensis. A total of 474 SNPs and 97 InDels were identified. Five genetic regions with high levels of variation (Pi > 0.015), trnS-trnG, ccsA-ndhD, psbI-trnS, trnT-psbD and ndhF-rpl32 were revealed. Conclusion: We reported the cp genome of S. sphenanthera and revealed the SNPs and InDels between the cp genomes of S. sphenanthera and S. chinensis. This study shed light on the species identification and further phylogenetic study within the genus of Schisandra.

[Decipherment of herb medicine Nanwuweizi and Wuweizi in Chinese ancient literature].

Nanwuweizi( Schisandrae Sphenantherae Fructus) and Wuweizi( Schisandrae Chinensis Fructus) have long-term history of use as common traditional Chinese medicines since the Eastern Han Dynasty( AD.25-220 year).However their information are always confused in ancient literature because they were both used as " Wuweizi". Nanwuweizi and Wuweizi are faced with problems such as confused distribution of producing areas,unclear source plants and efficacy characteristics,which limit modern resource development and application. Based on ancient literatures of materia medica,this study conducted a systematic review from several aspects,i.e. the name,distribution of producing areas,source plants,efficacy characteristics and processing of the two medicines in ancient time. This study clarified five main aspects,as following,ancient production areas and corresponding modern distribution areas; source plants used for medicinal purposes in ancient time; application period and application scope; efficacy characteristics in clinical application;processing method. This study provides a reference for evaluating the quality and for their clinical application and reasonable development of Nanwuweizi and Wuweizi.

DNA barcoding of Corydalis, the most taxonomically complicated genus of Papaveraceae.

The genus Corydalis is recognized as one of the most taxonomically challenging plant taxa. It is mainly distributed in the Himalaya-Hengduan Mountains, a global biodiversity hotspot. To date, no effective solution for species discrimination and taxonomic assignment in Corydalis has been developed. In this study, five nuclear and chloroplast DNA regions, ITS, ITS2, matK, rbcL, and psbA-trnH, were preliminarily assessed based on their ability to discriminate Corydalis to eliminate inefficient regions, and the three regions showing good performance (ITS, ITS2 and matK) were then evaluated in 131 samples representing 28 species of 11 sections of four subgenera in Corydalis using three analytical methods (NJ, ML, MP tree; K2P-distance and BLAST). The results showed that the various approaches exhibit different species identification power and that BLAST shows the best performance among the tested approaches. A comparison of different barcodes indicated that among the single barcodes, ITS (65.2%) exhibited the highest identification success rate and that the combination of ITS + matK (69.6%) provided the highest species resolution among all single barcodes and their combinations. Three Pharmacopoeia-recorded medicinal plants and their materia medica were identified successfully based on the ITS and ITS2 regions. In the phylogenetic analysis, the sections Thalictrifoliae, Sophorocapnos, Racemosae, Aulacostigma, and Corydalis formed well-supported separate lineages. We thus hypothesize that the five sections should be classified as an independent subgenus and that the genus should be divided into three subgenera. In this study, DNA barcoding provided relatively high species discrimination power, indicating that it can be used for species discrimination in this taxonomically complicated genus and as a potential tool for the authentication of materia medica belonging to Corydalis.

Hiya: A new genus segregated from Hypolepis in the fern family Dennstaedtiaceae, based on phylogenetic evidence and character evolution.

The relationship of Hypolepis brooksiae, H. nigrescens, and H. scabristipes to the remainder of Hypolepis (Dennstaedtiaceae) has been questioned by previous authors based on their unique combination of morphological characters and different base chromosome number. Using four chloroplast genes including rbcL, atpA, rpL6, and rps4-trnS intergenic spacer (IGS) from 32 samples, representing 24 species of Dennstaedtiaceae, we recovered a clade comprising H. brooksiae and H. nigrescens, distinct from the remaining species of Hypolepis. This clade is resolved as sister to the clade comprising Blotiella, Paesia and Histiopteris. We reconstructed ancestral states of 16 morphological characters and found that this clade is distinguished by indeterminate, scandent leaves exhibiting rhythmic growth, provided with recurved black-tipped prickles, and stipule-like pinnules that protect the emerging crosier and pinnae departures, rachis-costa architecture where the adaxial sulcus is confluent with the next lower order, and a base chromosome number of x = 29. In light of this molecular and morphological evidence, we describe a new genus, Hiya, and provide nomenclatural combinations to accommodate the three known species segregated from Hypolepis: Hiya brooksiae, Hiya nigrescens, and Hiya scabristipes.