Resina Draconis, a rare and precious traditional medicine in China, is known as the "holy medicine for promoting blood circulation". According to the national drug standard, it's derived from the resin extracted from the wood of Dracaena cochinchinensis, a Liliaceae plant. In addition, a variety of Dracaena species all over the world can form red resins, and there is currently no molecular identification method that can efficiently identify the origin of Dracaena medicinal materials. In this study, seven species of Dracaena distributed in China were selected as the research objects. Four commonly used DNA barcodes(ITS2, matK, rbcL and psbA-trnH), and four highly variable regions(trnP-psaJ, psbK-psbI, trnT-trnL, clpP) in chloroplast genome were used to evaluate the identification efficiency of Dracaena species. The results showed that clpP sequence fragment could accurately identify seven species of Dracaena plants. However, due to the long sequence of clpP fragment, there were potential problems in the practical application process. We found that the combined fragment "psbK-psbI+ trnP-psaJ" can also be used for accurate molecular identification of the Resina Draconis origin plants and relative species of Dracaena, which were both relatively short sequences in the combined fragment, showing high success rates of amplification and sequencing. Therefore, the "psbK-psbI+ trnP-psaJ" combined fragment can be used as the DNA barcode fragments for molecular identification of Resina Dracon's origin plants and relative species of Dracaena. Research on the identification of Dracaena species, the results of this study can be used to accurately identify the original material of Resina Draconis, and providing effective means for identification, rational development and application of Resina Draconis base source.
China ; DNA Barcoding, Taxonomic ; DNA, Plant/genetics* ; Dracaena/genetics* ; Plants ; Resins, Plant ; Sequence Analysis, DNA

DNA barcode molecular biological technique is used to identify the species of 23 unknown Li minority medicinal plants.DNA was extracted from 23 unknown medicines using the Plant Genomic DNA Extraction kit. The ITS2 and psbA-trnH regions were amplified and sequenced bi-directionally. The Codon Code Aligner V 7. 0. 1 was used to proofread and assemble the contigs and generated consensus sequences. All the sequences were submitted to Traditional Chinese Medicine DNA Barcode Database and NCBI Gen Bank to get information of the species identifications. If the maximum similarity of the identification result is ≥ 97%,exact species can be known. If it is between 97% and 90%,samples' genus can be confirmed; If it is <90%,then we can only confirm its family. Finally there are 17 samples can be identified to species level,5 can be identified to genus level and 1 can be identified to family level. This shows that DNA barcoding used in medicinal plants molecular identification,can identify unknown species rapidly and accurately.
DNA Barcoding, Taxonomic ; DNA, Plant ; genetics ; Medicine, Chinese Traditional ; Plants, Medicinal ; classification ; Sequence Analysis, DNA

DNA metabarcoding,one rapid and robust method using specific standard DNA fragments,has been widely used for rapid species identification of a bulk sample through high-throughput sequencing technologies.While it has been widely used in the studies of metagenomics,animal and plant biodiversity,it has gradually come to be used as a profitable method in species identification of mixed Chinese herbal medicines.In this paper,we mainly summarize the current studies of the application of DNA metabarcoding in species identification of mixed Chinese herbal medicines.Moreover,high-throughput sequencing technologies adopted in those studies,such as Sanger,the next-generation,and third-generation sequencing technologies,are discussed.It is conducted to provide a theoretical guidance for the application of DNA metabarcoding in species identification of mixed Chinese herbal medicines and in more other biodiversity studies.
Biodiversity ; DNA Barcoding, Taxonomic ; DNA, Plant ; genetics ; Drugs, Chinese Herbal ; analysis ; High-Throughput Nucleotide Sequencing ; Plants, Medicinal ; classification

Enhancers activate transcription in a distance-, orientation-, and position-independent manner, which makes them difficult to be identified. Self-transcribing active regulatory region sequencing (STARR-seq) measures the enhancer activity of millions of DNA fragments in parallel. Here we used STARR-seq to generate a quantitative global map of rice enhancers. Most enhancers were mapped within genes, especially at the 5' untranslated regions (5'UTR) and in coding sequences. Enhancers were also frequently mapped proximal to silent and lowly-expressed genes in transposable element (TE)-rich regions. Analysis of the epigenetic features of enhancers at their endogenous loci revealed that most enhancers do not co-localize with DNase I hypersensitive sites (DHSs) and lack the enhancer mark of histone modification H3K4me1. Clustering analysis of enhancers according to their epigenetic marks revealed that about 40% of identified enhancers carried one or more epigenetic marks. Repressive H3K27me3 was frequently enriched with positive marks, H3K4me3 and/or H3K27ac, which together label enhancers. Intergenic enhancers were also predicted based on the location of DHS regions relative to genes, which overlap poorly with STARR-seq enhancers. In summary, we quantitatively identified enhancers by functional analysis in the genome of rice, an important model plant. This work provides a valuable resource for further mechanistic studies in different biological contexts.
Acetylation ; Base Sequence ; Deoxyribonuclease I ; metabolism ; Enhancer Elements, Genetic ; Epigenesis, Genetic ; Genes, Plant ; Genomics ; methods ; Histone Code ; genetics ; Histones ; metabolism ; Models, Genetic ; Oryza ; genetics ; Promoter Regions, Genetic ; genetics ; Repetitive Sequences, Nucleic Acid ; genetics ; Sequence Analysis, DNA ; Transcription, Genetic

Despite the large number of genomic and transcriptomic resources in maize, there is still much to learn about the function of genes in developmental and biochemical processes. Some maize mutants that were generated by gamma-irradiation showed clear segregation for the kernel phenotypes in B73 × Mo17 F2 ears. To better understand the functional genomics of kernel development, we developed a mapping and gene identification pipeline, bulked segregant exome sequencing (BSEx-seq), to map mutants with kernel phenotypes including opaque endosperm and reduced kernel size. BSEx-seq generates and compares the sequence of the exon fraction from mutant and normal plant F2 DNA pools. The comparison can derive mapping peaks, identify deletions within the mapping peak, and suggest candidate genes within the deleted regions. We then used the public kernel-specific expression data to narrow down the list of candidate genes/mutations and identified deletions ranging from several kb to more than 1 Mb. A full deletion allele of the Opaque-2 gene was identified in mutant 531, which occurs within a ∼200-kb deletion. Opaque mutant 1486 has a 6248-bp deletion in the mapping interval containing two candidate genes encoding RNA-directed DNA methylation 4 (RdDM4) and AMP-binding protein, respectively. This study demonstrates the efficiency and cost-effectiveness of BSEx-seq for causal mutation mapping and candidate gene selection, providing a new option in mapping-by-sequencing for maize functional genomics studies.
Chromosome Mapping ; methods ; DNA, Plant ; genetics ; DNA-Binding Proteins ; genetics ; Endosperm ; Exome ; genetics ; Exons ; genetics ; Gene Deletion ; Genomics ; Phenotype ; Plant Proteins ; genetics ; Sequence Analysis, DNA ; methods ; Transcription Factors ; genetics ; Zea mays ; genetics

In this study, we analyzed the physical interactions of the dominant negative isoform of MoYpt7. Our results show that MoYpt7 interacts with MoGdi1. The dominant negative isoform of MoYpt7 (dominant negative isoform, N125I) is essential for colony morphology, conidiation, and pathogenicity in the rice blast fungus. These results further demonstrate the biological functions of MoYpt7 in Magnaporthe oryzae.
DNA Mutational Analysis ; Fungal Proteins/metabolism* ; Gene Expression Regulation, Fungal ; Genes, Fungal ; Green Fluorescent Proteins/metabolism* ; Magnaporthe/genetics* ; Microscopy, Fluorescence ; Mutation ; Oryza/microbiology* ; Phenotype ; Plant Diseases/microbiology* ; Protein Isoforms

Targeting Induced Local Lesions IN Genomes (TILLING) is a reverse genetics strategy for the high-throughput screening of induced mutations. γ radiation, which often induces both insertion/deletion (Indel) and point mutations, has been widely used in mutation induction and crop breeding. The present study aimed to develop a simple, high-throughput TILLING system for screening γ ray-induced mutations using high-resolution melting (HRM) analysis. Pooled rice (Oryza sativa) samples mixed at a 1:7 ratio of Indel mutant to wild-type DNA could be distinguished from the wild-type controls by HRM analysis. Thus, an HRM-TILLING system that analyzes pooled samples of four M₂ plants is recommended for screening γ ray-induced mutants in rice. For demonstration, a γ ray-mutagenized M₂ rice population (n=4560) was screened for mutations in two genes, OsLCT1 and SPDT, using this HRM-TILLING system. Mutations including one single nucleotide substitution (G→A) and one single nucleotide insertion (A) were identified in OsLCT1, and one trinucleotide (TTC) deletion was identified in SPDT. These mutants can be used in rice breeding and genetic studies, and the findings are of importance for the application of γ ray mutagenesis to the breeding of rice and other seed crops.
Crops, Agricultural/radiation effects* ; Gamma Rays ; Genetic Techniques ; Genome, Plant ; Homozygote ; INDEL Mutation ; Mutagenesis ; Oryza/radiation effects* ; Plant Breeding ; Polymerase Chain Reaction ; Seeds ; Sequence Analysis, DNA ; Sequence Deletion

Most of Chinese medicinal herbs are subjected to traditional processing procedures, including stir-frying, charring, steaming, boiling, and calcining before they are released into dispensaries. The marketing and identification of processed medicinal materials is a growing issue in the marketplace. However, conventional methods of identification have limitations, while DNA mini-barcoding, based on the sequencing of a short-standardized region, has received considerable attention as a new potential means to identify processed medicinal materials. In the present study, six DNA barcode loci including ITS2, psbA-trnH, rbcL, matK, trnL (UAA) intron and its P6 loop, were employed for the authentication of 45 processed samples belonging to 15 species. We evaluated the amplification efficiency of each locus. We also examined the identification accuracy of the potential mini-barcode locus, of trnL (UAA) intron P6 loop. Our results showed that the five primary barcode loci were successfully amplified in only 8.89%-20% of the processed samples, while the amplification rates of the trnL (UAA) intron P6 loop were higher, at 75.56% successful amplification. We compared the mini-barcode sequences with Genbank using the Blast program. The analysis showed that 45.23% samples could be identified to genus level, while only one sample could be identified to the species level. We conclude that trnL (UAA) p6 loop is a candidate mini-barcode that has shown its potential and may become a universal mini-barcode as complementary barcode for authenticity testing and will play an important role in medicinal materials control.
DNA Barcoding, Taxonomic ; methods ; DNA, Plant ; genetics ; Discriminant Analysis ; Drugs, Chinese Herbal ; chemistry ; classification ; Introns ; Plant Proteins ; genetics ; Plants, Medicinal ; chemistry ; classification ; genetics

Hyoscyami Semen, the mature dried seed of Hyoscyamus niger L., has long been used as a traditional Chinese medicine to treat human diseases. Hyoscyami Semen is found in local markets in China. In markets, sellers and buyers commonly inadvertently mix the seeds of H. niger with the seeds of related species such as Hygrophila salicifolia (Vahl) Nees, Astragalus complanatus R. Br., Cuscuta australis R. Br., Cuscuta chinensis Lam., and Impatiens balsamina L. because of their similar morphologies or similar names. Thus, developing a reliable method for discriminating H. niger seeds from its adulterants is necessary to reduce confusion and ensure the safe use of Hyoscyami Semen. The present study was designed to evaluate the efficiency of high-resolution melting analysis combined with DNA barcoding (Bar-HRM) with internal transcribed spacer 2 to discriminate H. niger. Our results show that Bar-HRM successfully identified the adulterants and detected the proportion of H. niger DNA extract within an admixture. In particular, HRM detected H. niger DNA extract in A. complanatus DNA extract at concentrations as low as 1%. In conclusion, the Bar-HRM method developed in the present study for authenticating H. niger is rapid and cost-effective. It can be used in the future to guarantee the purity of Hyoscyami Semen for the clinical use.
China ; DNA Barcoding, Taxonomic ; methods ; DNA, Intergenic ; chemistry ; genetics ; DNA, Plant ; chemistry ; genetics ; Discriminant Analysis ; Drug Contamination ; Drugs, Chinese Herbal ; chemistry ; Hyoscyamus ; genetics ; growth & development ; Seeds ; genetics ; growth & development ; Transition Temperature

In this study, we collected rhizosphere soils and root samples from a post-mining area and a natural forest area in Jecheon, Korea. We extracted spores of arbuscular mycorrhizal fungi (AMF) from rhizospheres, and then examined the sequences of 18S rDNA genes of the AMF from the collected roots of plants. We compared the AMF communities in the post-mining area and the natural forest area by sequence analysis of the AMF spores from soils and of the AMF clones from roots. Consequently, we confirmed that the structure of AMF communities varied between the post-mining area and the natural forest area and showed significant relationship with heavy metal contents in soils. These results suggest that heavy metal contamination by mining activity significantly affects the AMF community structure.
Chungcheongbuk-do ; Clone Cells ; DNA, Ribosomal ; Forests ; Fungi* ; Korea* ; Mining ; Mycorrhizae ; Plant Roots* ; Plants* ; Rhizosphere ; Sequence Analysis ; Soil* ; Spores