Search

The DArk Matter Particle Explorer (DAMPE) is well suitable for searching for monochromatic and sharp $\gamma$-ray structures in the GeV$-$TeV range thanks to its unprecedented high energy resolution. In this work, we search for $\gamma$-ray line structures using five years of DAMPE data. To improve the sensitivity, we develop two types of dedicated data sets (including the BgoOnly data which is the first time to be used in the data analysis for the calorimeter-based gamma-ray observatories) and adopt the signal-to-noise ratio optimized regions of interest (ROIs) for different DM density profiles. No line signals or candidates are found between 10 and 300 GeV in the Galaxy. The constraints on the velocity-averaged cross section for $\chi\chi \to \gamma\gamma$ and the decay lifetime for $\chi \to \gamma\nu$, both at 95% confidence level, have been calculated and the systematic uncertainties have been taken into account. Comparing to the previous Fermi-LAT results, though DAMPE has an acceptance smaller by a factor of $\sim 10$, similar constraints on the DM parameters are achieved and below 100 GeV the lower limits on the decay lifetime are even stronger by a factor of a few. Our results demonstrate the potential of high-energy-resolution observations on dark matter detection., Comment: 14 pages, 8 figures. Update the content to keep up with the published version

The star fruit is a perennial woody fruit tree, which can blossom and bear fruit many times a year. The time and quantity of flowering are the key indicators of its economic value. However, the flowering molecular mechanism of star fruit is still unknown. This study provides a genome-wide analysis of the key flowering genes of star fruit. Based on a previous morphological study of flower bud differentiation, the reproductive buds, vegetative buds and mature leaves of star fruit were sampled for transcriptome analysis. The results showed that the expression of GI, COL4, COL5, FT, FCA, FVE, PIF4, LFY, SVP-like, AP1 and FUL was correlated with floral induction and transition. The expression of TFL1, SVP-like genes (Yangtao2015203 and Yangtao2021074) was correlated with the inhibition of floral transition. Thus, we proposed a putative network of flower blooming in star fruit. This study provides useful information for investigating the genetic mechanism of flowering in star fruit and other perennial woody fruit trees.

Orchids are horticultural plants with significant ornamental and economic value. Increasing market circulation and rising trade in orchids is forcing breeders to develop varieties with unique characteristics, including flower color, morphology, and resistance using a range of approaches, including traditional and molecular breeding. Advances in high-throughput technologies have generated extensive data sets with greater sequencing depths and broader coverage, providing the potential for discovering new genes/pathways that give rise to key traits. Several attempts have been made to use emerging molecular and omics methods to accelerate the breeding process in certain of the commercially valuable orchids. This review consolidates current approaches and achievements in orchid breeding and discusses their future applications for improving the resistance, ornamental, and other valuable characteristics of these plants.

The wood sorrel family, Oxalidaceae, is mainly composed of annual or perennial herbs, a few shrubs, and trees distributed from temperate to tropical zones. Members of Oxalidaceae are of high medicinal, ornamental, and economic value. Despite the rich diversity and value of Oxalidaceae, few molecular markers or plastomes are available for phylogenetic analysis of the family. Here, we reported four new whole plastomes of Oxalidaceae and compared them with plastomes of three species in the family, as well as the plastome of Rourea microphylla in the closely related family Connaraceae. The eight plastomes ranged in length from 150,673 bp (Biophytum sensitivum) to 156,609 bp (R. microphylla). Genome annotations revealed a total of 129–131 genes, including 83–84 protein-coding genes, eight rRNA genes, 37 tRNA genes, and two to three pseudogenes. Comparative analyses showed that the plastomes of these species have minor variations at the gene level. The smaller plastomes of herbs B. sensitivum and three Oxalis species are associated with variations in IR region sizes, intergenic region variation, and gene or intron loss. We identified sequences with high variation that may serve as molecular markers in taxonomic studies of Oxalidaceae. The phylogenetic trees of selected superrosid representatives based on 76 protein-coding genes corroborated the Oxalidaceae position in Oxalidales and supported it as a sister to Connaraceae. Our research also supported the monophyly of the COM (Celastrales, Oxalidales, and Malpighiales) clade., Highlights • Plastomes from the genus Biophytum (Oxalidaceae) and the family Connaraceae are reported for the first time. • Little plastome variation was observed among genera of Oxalidaceae. • Several divergence hotspot regions were identified in the Oxalidaceae species. • The systematic position of Oxalidaceae was confirmed as sister to Connaraceae within Oxalidales.

A population genomic approach was employed to investigate the diversity within species to create a more robust, lineage-specific conservation strategy for an endangered orchid. Pleione formosana is a species native to southeastern China and Taiwan, where it is distributed at an altitude range of 1,200–2,500 m the foggy mountain area and grows in mosses on half-shaded rocks or tree trunks. To identify whether the level of genetic diversity in the species, we used genotyping by sequencing (GBS) to analysis the sub-populations of the species. Fifty-eight individuals of P. formosana were sampled from a total of nine populations within continental island Taiwan and three populations in China as outgroup. Treatment of all samples involved five major steps: sample preparation, library assembly, sequencing, SNP calling and diversity analysis. GBS markers confirmed the China outgroup as distinct, and provided resolution of two clusters of population genetic structure in Taiwan. Outliers provide higher genetic differentiation, and some GBS tags associated with climatic factor were found. Genomic diversity identified among the three clusters suggests that conservation of this species will be best served by considering them as three evolutionary significant units (ESUs). This approach will maximize evolutionary potential among all species during increased isolation and environmental change. According to the genetic consequences, restoration strategies should be carried out in all populations to preserve genetic diversity and evolutionary potential for different environmental factors.

Due to the small degree of morphological and karyotype variations, the Pleione formosana, a well-known and valuable ornamental orchid, was treated as one member of the P. bulbocodioides complex including P. bulbocodioides, P. pleionoides and P. limprichtii, as well. The taxonomy of this complex remains problematic. P. hui was described in Anfu, Jiangxi, China, but was treated as synonym of P. formosana latter, making its taxonomic status remains controversy. In this study, we used molecular, morphological and cytological analyses to identify the relationship of P. formosana and other related species. Results base on phylogenetic analyses of chloroplast DNA and nuclear ribosomal Internal Transcribed Spacer sequence datasets indicated that Anfu samples were obviously separated from the P. formosana accessions. Network analysis showed three different groups: the P. formosana group, the P. bulbocodioides complex and the hybrid group. Morphological analysis also showed that Anfu population was significantly different from other P. formosana populations. Results of chromosome ploidy analyses showed that P. formosana was diploid and Anfu population was tetraploid, indicating that they are not the same species. In conclusion, we suggest to exclude P. formosana from P. bulbocodiodes complex, and restore the speceies rank of P. hui.

Parallel to traditional Th1/Th2/Th17/Treg lineages, granulocyte-macrophage colony-stimulating factor-producing T helper (Th-GM) cells have been identified as a distinct subset of T helper cells (GM-CSF

Two new bibenzyls (

Two new bibenzyls (1 and 2) were isolated from the pseudobulbs of Pleione grandiflora (Rolfe) Rolfe along with six known compounds, including isoarundinin I (3), isoarundinin II (4), bulbocodin D (5), batatasin III (6), 5,3'-dihydroxy- 4-(p-hydroxybenzyl)-3-methoxybibenzyl (7) and shancigusin F (8). Their structures were established on the basis of spectroscopic methods. These compounds showed potent DPPH free radical scavenging effects with IC50 values ranging from 49.72 ± 0.35 μM to 65.41 ± 0.49 μM.

Analyses of the genome sequences and expression data for two closely related mycoheterotrophic orchid species provide insights into the genomic basis underlying the evolution of mycoheterotrophy. To improve our understanding of the origin and evolution of mycoheterotrophic plants, we here present the chromosome-scale genome assemblies of two sibling orchid species: partially mycoheterotrophic Platanthera zijinensis and holomycoheterotrophic Platanthera guangdongensis. Comparative analysis shows that mycoheterotrophy is associated with increased substitution rates and gene loss, and the deletion of most photoreceptor genes and auxin transporter genes might be linked to the unique phenotypes of fully mycoheterotrophic orchids. Conversely, trehalase genes that catalyse the conversion of trehalose into glucose have expanded in most sequenced orchids, in line with the fact that the germination of orchid non-endosperm seeds needs carbohydrates from fungi during the protocorm stage. We further show that the mature plant of P. guangdongensis, different from photosynthetic orchids, keeps expressing trehalase genes to hijack trehalose from fungi. Therefore, we propose that mycoheterotrophy in mature orchids is a continuation of the protocorm stage by sustaining the expression of trehalase genes. Our results shed light on the molecular mechanism underlying initial, partial and full mycoheterotrophy.

Background: As a method to identify Differentially Expressed Genes (DEGs), Non- Negative Matrix Factorization (NMF) has been widely praised in bioinformatics. Although NMF can make DEGs to be easily identified, it cannot provide more associated information for these DEGs. Objective: The methods of network analysis can be used to analyze the correlation of genes, but they caused more data redundancy and great complexity in gene association analysis of high dimensions. Dimensionality reduction is worth considering in this condition. Methods: In this paper, we provide a new framework by combining the merits of two: NMF is applied to select DEGs for dimensionality reduction, and then Weighted Gene Co-Expression Network Analysis (WGCNA) is introduced to cluster on DEGs into similar function modules. The combination of NMF and WGCNA as a novel model accomplishes the analysis of DEGs for cholangiocarcinoma (CHOL). Results: Some hub genes from DEGs are highlighted in the co-expression network. Candidate pathways and genes are also discovered in the most relevant module of CHOL. Conclusion: The experiments indicate that our framework is effective and the works also provide some useful clues to the reaches of CHOL.

The DArk Matter Particle Explorer (DAMPE) is a satellite-borne experiment, in operation since 2015, aimed at studying high-energy gamma rays and cosmic nuclei fluxes. Of the various sub-detectors in the DAMPE payload, the Silicon-Tungsten tracKer-converter (STK) plays a significant role in the charge measurement of incoming ions. Depending on the angle of inclination of the impinging particle and its position of impact on these strips, the collected charge can spread between the strips which results in some fractional signal loss. The $\eta$ variable is used to identify this spread of charge across the strips and correct for the associated charge loss. This brings us closer to accurate determination of particle charge which is crucial for ensuring a good discrimination between particles. The $\eta$-correction is, therefore, expected to play an important role in the determination of heavy ions by the DAMPE detector. It has helped reduce the proton background for the helium identification in STK by a factor of 1.5 for MIP tracks. It has been sucessfully applied to carbon nuclei and its application to heavier nuclei is currently being studied.

Since its launch, in December 2015, the satellite-based DAMPE (DArk Matter Particle Explorer) particle detector is taking data smoothly. The Silicon-Tungsten tracKer-converter (STK) of DAMPE consists of six tracking planes (6x, 6y) of single-sided silicon micro-strip detectors mounted on seven support trays. The STK is able to measure the charge and precisely reconstruct the track of traversing charged particles. Tungsten plates (1 mm thick) are integrated in the second, third and fourth tray from the top to serve as $\gamma \rightarrow e^+e^−$ converters. Commissioned rapidly after the launch, the STK is running extremely well since then. The STK in-orbit calibration and performance during its first more than 5 years of operation, including the noise behaviour and the thermal and mechanical stability, are presented in this contribution.

The DArk Matter Particle Explorer (DAMPE) is the first Chinese cosmic-ray direct detection experiment. It has been operating smoothly on-orbit since its successful launch at the end of 2015. Currently, its sub-detectors and the satellite are in good working order. The DAMPE payload employs a BGO Calorimeter for energy measurements, trigger and e/p identification. The calorimeter is constructed of 308 BGO crystals, and PMTs are coupled to the crystals with optical filters to readout scintillation light. In this work, we present the status and performance of the calorimeter, including status of detector units, energy measurement, especially in TeV range, detector endurance, and long term performance in a duration of 65 months.

The Fermi bubbles are two large structures above and below the Galactic Plane. They are first discovered by Fermi-LAT and thought to be related to the jet or the wind from the Galactic center. The DArk Matter Particle Explorer (DAMPE) is a space-borne high energy particle telescope aiming at measuring cosmic rays and photons in a broad energy range. In this work, we use 4.8 years of DAMPE photon data to search for the emission from the Fermi Bubbles. We calculate the TS values of the lobes and the significance of its curved spectrum. The obtained spectral parameters are then compared with those from the Fermi-LAT. We also search for the emission from the cocoon in the southeast part of lobes. Since the Galactic diffuse emission (GDE) model is a major source of systematic uncertainty, we also switch to the GDE models calculated with Galprop and evaluate the influence.

Melastomataceae have abundant morphological diversity with high economic and ornamental merit in Myrtales. The phylogenetic position of Myrtales is still contested. Here, we report the first chromosome-level genome assembly of Melastoma dodecandrum in Melastomataceae. The assembled genome size was 299.81 Mb with a contig N50 value of 3.00 Mb. Genome evolution analysis indicated that M. dodecandrum, Eucalyptus grandis and Punica granatum were clustered into a clade of Myrtales and formed a sister group with the ancestor of fabids and malvids. We found that M. dodecandrum experienced four whole-genome polyploidization events: the ancient event was shared with most eudicots, one event was shared with Myrtales, and the other two events were unique to M. dodecandrum. Moreover, we identified MADS-box genes and found that the AP1-like genes expanded, and AP3-like genes might have undergone subfunctionalization. We found that the SUAR63-like genes and AG-like genes showed different expression patterns in stamens, which may be associated with heteranthery. In addition, we found that LAZY1-like genes were involved in the negative regulation of stem branching development, which may be related to its creeping features. Our study sheds new light on the evolution of Melastomataceae and Myrtales, which provides a comprehensive genetic resource for future research.

The DArk Matter Particle Explorer (DAMPE), a space-based high energy particle detector, has been operated on-orbit for more than five years. The large geometric factor and good charge resolution enable DAMPE to have very good potential to measure cosmic-rays up to 100 TeV. Knowledge of the boron to carbon (B/C) flux ratio is very important in understanding the prop- agation of cosmic rays, especially in TeV energy range. In this contribution, the latest progress of the B/C flux ratio analysis based on the flight data collected by DAMPE during the 5 years of operation, is presented.

Organic dyes generating from many industries are considered as a potential source of water-pollution and have negative effects on human health. The present study was aimed to construct a green synthesis method for fabrication of ZnS-based dual nano-semiconductors and to compare the photocatalytic properties for removing cationic and anionic dyes. ZnS nanoparticles were synthesized using a template synthesis in bovine serum albumin (BSA) solution and then ZnS/PbS, ZnS/CdS and ZnS/Ag2S dual nano-semiconductors were prepared using ion-exchange method. Prepared nano-semiconductors were characterized by using HR-TEM, XRD, FTIR, TG/DTA and AAS. Moreover, photocatalytic activity of prepared nano-semiconductors was tested against Rhodamine B (cationic dye) and Methyl Orange (anionic dye). Results revealed that a controllable ZnS/PbS, ZnS/CdS and ZnS/Ag2S ratio in nano-semiconductors can be achieved by adjusting the ion-exchange time. Prepared ZnS based composites exhibited higher photocatalytic efficiency than that of ZnS alone. In addition, photocatalytic activity of ZnS-based dual nano-semiconductors was found to be dependent upon composition and ratio of sulphides in nano-semiconductors with environmental pH. It was concluded that the combination of template synthesis and ion-exchange method is a feasible approach to fabricate new photocatalysts with higher photocatalytic activity.

Semiconductor nanomaterials not only bring great convenience to peoples lives but also become a potential hazard to human health. The purpose of this study was to evaluate the toxicity of CuS/CdS nanocomposites in hepatocytes and mice liver. The CuS/CdS semiconductor nanocomposites were synthesized by a biomimetic synthesis - ion exchange strategy. Nanosize was confirmed by high-resolution transmission electron microscopy and dynamic light scattering. The composition and physical properties were measured by powder X-ray diffraction, Fourier transform infrared spectra, atomic absorption spectroscopy, thermogravimetry-differential scanning calorimetry and zeta potential analysis. The results revealed that CuS/CdS nanocomposites had 8.7 nm diameter and negative potential. Ion exchange time could adjust the ratio of CuS and CdS in nanocomposites. The toxicological study revealed that CuS/CdS nanocomposites could be internalized into liver cells, inhibited endogenous defense system (e.g. GSH and SOD), induced the accumulation of oxidation products (e.g. ROS, GSSG and MDA), and caused hepatocyte apoptosis. The in vivo experiments in Balb/c mice showed that the experimental dose (4 mg/kg) didn't cause observable changes in mice behavior, physical activity and pathological characteristics, but the continuous accumulation of Cd2+ in the liver and kidney might be responsible for its long-term toxicity.

Background. Q-1 is a novel compound extracted from the Miao medicine Tiekuaizi. Although Q-1 is known to be a coumarin derivative, its structure has not been deposited in the ACX library. Our previous study showed that Q-1 inhibits the activity of inflammatory cells. This study explores the efficacy of Q-1 in regulating rheumatoid arthritis (RA). The findings show that Q-1 acts through the NF-κB signaling pathway. Methods. The effects of Q-1 were explored using a bovine type II collagen-induced arthritis (CIA) rat model. The CIA rats were intragastrically administered with high (30 mg·kg−1) or low (15 mg·kg−1) doses of Q-1. The control group was administered with an equal volume of drinking water, while the positive control group was administered with Tripterygium glycoside (9.45 mg·kg−1) for 28 consecutive days. The arthritis indices and ankle joint swelling rates were determined. The levels of IL-1β, IL-6, monocyte chemoattractant protein-1 (MCP-1) in serum and sialic acid (SA) in liver homogenate were determined by enzyme-linked immunosorbent assay (ELISA). The pathological features of the ankle joint were analyzed by hematoxylin and eosin (HE) staining. The IκB, P-IκB, P65, and P-P65 protein levels in synovial tissue were assayed by western blotting. Results. The arthritis index, ankle joint swelling rate, IL-1β, IL-6, and MCP-1 levels in serum, SA level in liver tissue, and IκB, P-IκB, P65, and P-P65 protein levels in synovial tissues were significantly higher ( P < 0.01 ) in the CIA model compared to the control group. RA was successfully replicated by the CIA model, as shown by the joint swelling results and histopathological sections of the ankle. Notably, all the above indicators decreased significantly ( P < 0.01 ) after treatment with Q-1 compared to the model. In addition, animals treated with Q-1 showed lower inflammation in the ankle joints than the model rats. Conclusion. The findings indicate that Q-1 effectively inhibited RA in rats by downregulating IκB, P-IκB, P65, and P-P65, inhibiting the excessive release of inflammatory factors, and inhibiting the overactivation of the NF-κB signaling pathway.

Pleione pleionoides is a vulnerable orchid with significant ornamental values. Here, we report the first complete chloroplast genome of P. pleionoides. The circular genome was 159,468 bp in length and consisted of a pair of inverted repeats (IR 26,651 bp), which were separated by a large single copy region (LSC 87,461 bp) and a small single copy region (SSC 18,705 bp). It contained 115 unique genes, including 87 protein-coding genes, 38 tRNAs, and 8 rRNAs. The maximum likelihood phylogenetic analysis indicated that P. pleionoides and P. bulbocodioides cluster together and closely related to P. formosana.

Pleione chunii is a vulnerable epiphytic orchid with significant ornamental value. Here, we report the first complete chloroplast genome of P. chunii. The circular genome was 158,880 bp in length and consisted of a pair of inverted repeats (IR 26,465 bp), which were separated by a large single copy region (LSC 87,259 bp) and a small single copy region (SSC 18,691 bp). It contained 115 unique genes, including 87 protein-coding genes, 38 tRNAs, and eight rRNAs. The maximum-likelihood phylogenetic analysis indicated that P. chunii was sister to P. bulbocodioides and P. formosana.

Calanthe arcuata is an endemic terrestrial orchid in China with high value of ornament and breeding. Here, we reported the first complete chloroplast genome of this plant in this research. The circular genome is 158,735 bp in length and includes large single-copy (LSC) region of 87,348 bp, small single-copy (SSC) region of 18,489 bp, and a pair of invert repeats (IR) regions of 26,449 bp. It contains 136 genes, including 88 protein-coding (PCG), 38 transfer RNA (tRNA), and eight ribosomal RNA (rRNA) gene. The phylogenetic analysis indicated that C. arcuata is the sister to C. davidii and C. triplicata.

Indigo-containing plant tissues change blue after a freezing treatment, which is accompanied by changes in indigo and its related compounds.In this study, we surveyed the dynamic change ofThe non-targeted metabolomics and targeted metabolomics results revealed a total of 98 different metabolites, the contents of indole, indican, indigo, and indirubin were significantly different after the change to blue from the freezing treatment. A transcriptome analysis screened ten different genes related to indigo upstream biosynthesis, including three anthranilate synthase genes, two phosphoribosyl-anthranilate isomerase genes, one indole-3-glycerolphosphate synthase gene, five tryptophan synthase genes. In addition, we further candidate 37 cytochrome P450 enzyme genes, one uridine diphosphate glucosyltransferase gene, and 24

Background Q-1 is a novel compound extracted from the Miao medicine Tiekuaizi. Although Q-1 is known to be a coumarin derivative, its structure has not been deposited in the ACX library. Our previous study showed that Q-1 inhibits the activity of inflammatory cells. This study explores the efficacy of Q-1 in regulating rheumatoid arthritis (RA). The findings show that Q-1 acts through the NF-κB signaling pathway. Methods The effects of Q-1 were explored using a bovine type II collagen-induced arthritis (CIA) rat model. The CIA rats were intragastrically administered with high (30 mg·kg−1) or low (15 mg·kg−1) doses of Q-1. The control group was administered with an equal volume of drinking water, while the positive control group was administered with Tripterygium glycoside (9.45 mg·kg−1) for 28 consecutive days. The arthritis indices and ankle joint swelling rates were determined. The levels of IL-1β, IL-6, monocyte chemoattractant protein-1 (MCP-1) in serum and sialic acid (SA) in liver homogenate were determined by enzyme-linked immunosorbent assay (ELISA). The pathological features of the ankle joint were analyzed by hematoxylin and eosin (HE) staining. The IκB, P-IκB, P65, and P-P65 protein levels in synovial tissue were assayed by western blotting. Results The arthritis index, ankle joint swelling rate, IL-1β, IL-6, and MCP-1 levels in serum, SA level in liver tissue, and IκB, P-IκB, P65, and P-P65 protein levels in synovial tissues were significantly higher (P < 0.01) in the CIA model compared to the control group. RA was successfully replicated by the CIA model, as shown by the joint swelling results and histopathological sections of the ankle. Notably, all the above indicators decreased significantly (P < 0.01) after treatment with Q-1 compared to the model. In addition, animals treated with Q-1 showed lower inflammation in the ankle joints than the model rats. Conclusion The findings indicate that Q-1 effectively inhibited RA in rats by downregulating IκB, P-IκB, P65, and P-P65, inhibiting the excessive release of inflammatory factors, and inhibiting the overactivation of the NF-κB signaling pathway.

Oxalidaceae is one of the most important plant families in horticulture, and its key commercially relevant genus, Averrhoa, has diverse growth habits and fruit types. Here, we describe the assembly of a high-quality chromosome-scale genome sequence for Averrhoa carambola (star fruit). Ks distribution analysis showed that A. carambola underwent a whole-genome triplication event, i.e., the gamma event shared by most eudicots. Comparisons between A. carambola and other angiosperms also permitted the generation of Oxalidaceae gene annotations. We identified unique gene families and analyzed gene family expansion and contraction. This analysis revealed significant changes in MADS-box gene family content, which might be related to the cauliflory of A. carambola. In addition, we identified and analyzed a total of 204 nucleotide-binding site, leucine-rich repeat receptor (NLR) genes and 58 WRKY genes in the genome, which may be related to the defense response. Our results provide insights into the origin, evolution and diversification of star fruit.

Natural indigo, as one of the oldest dyes, is also a pivotal dye utilized in cotton fabrics today. A diversity of plants rich in indigo compounds belong to traditional Chinese herbal medicines. Indigo compounds have a variety of biological and pharmacological activities, including anticonvulsant, antibacterial, antifungal, antiviral and anticancer activities. A substantial progress in indigo biosynthesis has been made lately. This paper summarizes the value of indigo from the aspects of cultural history, biosynthetic pathways and the medicinal activities of its related derivatives involved in the pathways. In addition, the latest research advancements in indigo biosynthetic pathways is demonstrated in this paper, which would lay the theoretical foundation for the exploration and utilization of natural indigo.

Floral color polymorphism can provide great insight into species evolution from a genetic and ecological standpoint. Color variations between species are often mediated by pollinators and are fixed characteristics, indicating their relevance to adaptive evolution, especially between plants within a single population or between similar species. The orchid genus Pleione has a wide variety of flower colors, from violet, rose-purple, pink, to white, but their color formation and its evolutionary mechanism are unclear. Here, we selected the P. limprichtii population in Huanglong, Sichuan Province, China, which displayed three color variations: Rose-purple, pink, and white, providing ideal material for exploring color variations with regard to species evolution. We investigated the distribution pattern of the different color morphs. The ratio of rose-purple:pink:white-flowered individuals was close to 6:3:1. We inferred that the distribution pattern may serve as a reproductive strategy to maintain the population size. Metabolome analysis was used to reveal that cyanindin derivatives and delphidin are the main color pigments involved. RNA sequencing was used to characterize anthocyanin biosynthetic pathway-related genes and reveal different color formation pathways and transcription factors in order to identify differentially-expressed genes and explore their relationship with color formation. In addition, qRT-PCR was used to validate the expression patterns of some of the genes. The results show that PlFLS serves as a crucial gene that contributes to white color formation and that PlANS and PlUFGT are related to the accumulation of anthocyanin which is responsible for color intensity, especially in pigmented flowers. Phylogenetic and co-expression analyses also identified a R2R3-MYB gene PlMYB10, which is predicted to combine with PlbHLH20 or PlbHLH26 along with PlWD40-1 to form an MBW protein complex (MYB, bHLH, and WDR) that regulates PlFLS expression and may serve as a repressor of anthocyanin accumulation-controlled color variations. Our results not only explain the molecular mechanism of color variation in P. limprichtii, but also contribute to the exploration of a flower color evolutionary model in Pleione, as well as other flowering plants.

Pleione chunii is a vulnerable epiphytic orchid with significant ornamental value. Here, we report the first complete chloroplast genome of P. chunii. The circular genome was 158,880 bp in length a...

Cephalotus follicularis is a carnivorous plant native to southwest Australia that belongs to the monospecific family Cephalotaceae. It forms both carnivorous pitcher leaves and non-carnivorous flat...

Pleione formosana is an Endangered terrestrial orchid with significant ornamental values. Here, we report the first complete chloroplast genome of P. formosana. The circular genome was 159,843 bp i...

Pleione (Orchidaceae) is not only famous for the ornamental value in Europe because of its special color, but also endemic in Southern Asia for its use in traditional medicine. A great deal of research about its secondary metabolites and biological activities has been done on only three of 30 species of Pleione. Up to now, 183 chemical compounds, such as phenanthrenes, bibenzyls, glucosyloxybenzyl succinate derivatives, flavonoids, lignans, terpenoids, etc., have been obtained from Pleione. These compounds have been demonstrated to play a significant role in anti-tumor, anti-neurodegenerative and anti-inflammatory biological activities and improve immunity. In order to further develop the drugs and utilize the plants, the chemical structural analysis and biological activities of Pleione are summarized in this review.

Calanthe s.l. is the most diverse group in the tribe Collabieae (Orchidaceae), which are pantropical in distribution. Illumina sequencing followed by de novo assembly was used in this study, and the plastid genetic information of Calanthe s.l. was used to investigate the adaptive evolution of this taxon. Herein, the complete plastome of five Calanthe s.l. species (Calanthe davidii, Styloglossum lyroglossa, Preptanthe rubens, Cephalantheropsis obcordata, and Phaius tankervilliae) were determined, and the two other published plastome sequences of Calanthe s.l. were added for comparative analyses to examine the evolutionary pattern of the plastome in the alliance. The seven plastomes ranged from 150,181 bp (C. delavayi) to 159,014 bp (C. davidii) in length and were all mapped as circular structures. Except for the three ndh genes (ndhC, ndhF, and ndhK) lost in C. delavayi, the remaining six species contain identical gene orders and numbers (115 gene). Nucleotide diversity was detected across the plastomes, and we screened 14 mutational hotspot regions, including 12 non-coding regions and two gene regions. For the adaptive evolution investigation, three species showed positive selected genes compared with others, C. obcordata (cemA), S. lyroglossa (infA, ycf1 and ycf2) and C. delavayi (nad6 and ndhB). Six genes were under site-specific positive selection in Calanthe s.l., namely, accD, ndhB, ndhD, rpoC2, ycf1, and ycf2, most of which are involved in photosynthesis. These results, including the new plastomes, provide resources for the comparative plastome, breeding, and plastid genetic engineering of orchids and flowering plants.