Cytochrome P450 (CYP450) is a key element in the Ganoderma triterpenoid biosynthetic pathway. The catalytic reaction process for CYP450 requires NADPH / NADH for electron transfer. After searching the genome dataset of Ganoderma lucidum, the unique sequence encoding CYP450 and NADPH were discovered, separately. The open reading frames of GLCYP450 and GLNADPH were cloned separately using RT-PCR strategy from G lucidum. The appropriate restriction enzyme cutting sites were introduced at the 5' and 3' ends of gene sequence. The genes of GLCYP450 and GLNADPH were recombined into the yeast expression vector pESC-URA, leading to the formation of the yeast expression plasmid pESC-GLNADPH-GLCYP450. This study provides a foundation for researching Ganoderma triterpene biosynthesis using the approach of synthetic biology.

Codon usage bias is an important characteristic of genetic information transfer in organisms. Analysis of codon usage bias of different species is important for understanding the rules on genetic information transfer. The previous method for analysis of codon usage bias is mainly based on genomic data. However, this method is greatly limited, because the genome sequences of higher organisms are still not available up to now. In this study, we found that we could obtain the same optimal codons of Ganoderma lucidum (Curtis: Fr.) P. Karst based on its whole genomic data or large-scale transcriptomic data from its liquid-cultured hyphae, primordium and fruiting body, separately. This result indicated the feasibility to understand the codon usage bias based on the large-scale transcriptomic data. By calculating the proportion of rare codons of Escherichia coli and Saccharomyces cerevisiae in 26 terpene synthases (TS) of G. lucidum, we found that the rare codons of S. cerevisiae have a higher proportion in TS genes, while the rare codons of E. coli have relatively lower, suggesting that the TS genes of G. lucidum are possibly more difficult to be expressed in S. cerevisiae than in E. coli. Chemical synthesis of TS genes according to the yeast optimal codons will be an effective way to solve the problem on the mismatch of gene codon bias between the foreign genes and the host strain.

RNA-Sequencing (RNA-Seq) is a newly-developed method in transcriptome research, it can afford more accurate transcription information and be more quickly by using Next-generation Sequencing (NGS) technology. RNA-Seq has been widely used in various biological fields. Genuine traditional Chinese medicines (TCM), with good quality and therapeutic effect, were always praised highly and used by famous physicians. The geo-herbalism formation of TCM is based on the product of the gene expression at specific space and time. So it has been a research hotspot to analyze the mechanism of biosynthesis through RNA-Seq in the study on the secondary metabolism of medicinal plant. This article mainly illustrates the RNA-Seq and its advantages, it also discusses the potential application in genuine TCM, and it can provide useful information for other researchers.

3-Hydroxy-3-methylglutaryl coenzyme-A reductase (HMGR), the first enzyme of mavalonic acid pathway, is one of the key devices involved in ginsenoside biosynthesis based on synthetic biology approach. The open reading frame of a novel HMGR gene from Panax ginseng (PgHMGR2) was cloned and analyzed in this study. PgHMGR2-encoding protein showed 71.6% sequence similarity to a P. ginseng HMGR in GenBank. The full-length cDNA sequence of PgHMGR2 containing 1 770 bp, which encodes 589 amino acids, was cloned by RT-PCR strategy from P. ginseng. The bioinformatic analysis showed that PgHMGR2-encoding protein contained two transmembrane regions and the HMG_CoA_reductase domain, without signal peptide. The protein sequence of PgHMGR2 had the highest sequence similarity (99%) with Panax quinquefolius HMGR (GenBank accession No. ACV65036). The expression level of PgHMGR2 was the highest in flower based on a real-time PCR analysis, followed by leaf and root, and the lowest was in stem. The result will provide a foundation for exploring the molecular function of PgHMGR2 involved in ginsenoside biosynthesis based on synthetic biology approach in P. ginseng plants.

Research on medicinal model organism is one of the core technologies to promote the modernization of traditional Chinese medicine (TCM). The research progress of Salvia miltiorrhiza as medicinal model plant is summarized in this paper. The genome of S. miltiorrhiza is small and its life cycle is short, as well as this plant can be stably genetically transformed. Because S. miltiorrhiza possesses the important medicinal and economic values, recently the transcriptome and genome of S. miltiorrhiza have been significantly recovered. The research prospect of S. miltiorrhiza as medicinal model plant in TCM was discussed, including biosynthesis of active components and their genetic regulation, relationship between quality of TCM and ecological environments, and selective breeding of good quality lines. Furthermore, as medicinal model plant, the construction of mutant library for S. miltiorrhiza, the genome map with high quality, and the functional genome should be investigated. Accompanying modern investigation of life sciences, the platform for medicinal model plant, S. miltiorrhiza, will be promoted to be established. It is important to develop the ethnopharmacology and new drugs around the world.

Quality variation and ecotype classification of Chinese herbal medicine are important scientific problems in Daodi herbal medicine research. The diversity of natural environmental conditions has led to form unique multi-Daodi, multi-product areas that produce particular Chinese herbal medicine. China is one of three big American ginseng (Panax quinquefolium L.) producing areas worldwide, with over 300 years of application and 40 years of cultivation history. Long-term production practice has led to the formation of three big advocate produce areas in China: Northeast province, Beijing and Shandong. P. quinquefolium L. grown under certain environmental conditions will develop long-term adaptations that will lead to more stable strains (different ecotypes). P. quinquefolium L., can vary greatly in quality; however, the ecological mechanisms causing this variation are still unclear. Root samples were collected from four-year-old cultivated P. quinquefolium L. plants in the three major genuine (Daodi) American ginseng-producing areas of Northeast province, Beijing and Shandong province, China. Ultra-performance liquid chromatography was used to analyze the contents of eight ginsenosides (Rg1, Re, Rb1, Rb2, Rb3, Rc, Rd, Rg2). Data for nine ecological factors, including temperature, moisture and sunlight, were obtained from the ecological database of Geographic Information System for Traditional Chinese Medicine. Soil samples from the sampling sites were collected. Effective boron and iron, available nitrogen and potassium, as well as other trace elements and soil nutrients, were determined by conventional soil physicochemical property assay methods. Analytical methods of biostatistics and numerical taxonomy were used to divide ecotypes of the three main Panax quinquefolium L. producing areas in China based on ginsenoside content, climate, soil and other ecological factors. To our knowledge, this is the first time that ecological division of P. quinquefolium L. producing areas in China has ever been conducted. The results show that there are two chemoecotypes of P. quinquefolium L. in China: ginsenoside Rb1-Re from outside Shanhaiguan, and ginsenoside Rg2-Rd from inside Shanhaiguan. Similarly, there are two types of climatic characteristics: inside Shanhaiguan (Beijing, Shandong) and outside Shanhaiguan (Northeast). This suggests that the formation and differentiation of chemoecotypes of P. quinquefolium L. is closely related to variability of the climatic and geographical environment. Additionally, ecological variation of the three main producing areas, characteristics of two climatic ecotypes, and soil characteristics are also discussed and summarized. These results provide experimental scientific evidence of the quality variation and ecological adaptation of P. quinquefolium L. from different producing areas. They also deepen our understanding of the biological nature of Daodi P. quinquefolium L. formation, and offer novel research models for other multi-origin, multi-Daodi Chinese herbal medicines ecotypes. In addition, the results demonstrate the critical need for improving quality, appropriate ecological regionalization and promoting industrialized development of P. quinquefolium L.

DNA barcoding is a technique in which species identification and discovery are performed by using short and standard fragments of DNA sequences. In this study, eleven species of Paris, including seven varieties, were sampled. Five chloroplast sequences, psbA-trnH, rpoB, rpoC1, rbcL, matK, and one nuclear marker, the second internal transcribed spacer (ITS2) of ribosomal DNA, were amplified and sequenced. The PCR amplification and sequencing efficiency, intra- and inter-specific divergence and barcoding gap were used to evaluate different loci, and the identification efficiency was assessed using BLAST1 and Nearest Distance methods. The ITS2 sequences in the studied samples of Paris were amplified and sequenced successfully using primers designed by our group, while matK showed low level in the amplification and psbA-trnH was difficult for sequencing because of over 800 bp and poly (A) structure. Analysis of the intra- and inter-specific divergence and barcoding gap showed ITS2 was superior to other loci. The ITS2 showed a much higher percentage of success (100%) in identification than other five loci, none of which indicated more than 50% except matK (52.9%). The 2-locus combination of rbcL+matK didn't improve ability of authentication. In addition, the rate of successful identification with ITS2 kept 100% when the samples were expanded to 67 samples of 29 species. In conclusion, ITS2 can be used to correctly identify medicinal plants of Paris, and it will be a potential DNA barcode for identifying medicinal plants of other taxa.

Transcription factor is one of the key factors in the regulation of gene expression at the transcriptional level. It plays an important role in plant growth, active components biosynthesis and response to environmental change. This paper summarized the structure and classification of bHLH transcription factors and elaborated the research progress of bHLH transcription factors which regulate the active components in plants, such as flavonoids, alkaloids, and terpenoids. In addition, the possibility of increasing the concentration of active substances by bHLH in medicinal plants was assessed. The paper emphasized great significance of model plants and multidisciplinary research fields including modern genomics, transcriptomics, metabolomics and bioinformatics, providing the contribution to improve the discovery and function characterization of bHLH transcription factors. Accelerating the research in the mechanism of bHLH transcription factors on the regulation of active components biosynthesis will promote the development of breeding and variety improvement of Chinese medicinal materials, also ease the pressure of resources exhaustion of traditional Chinese medicine home and abroad.

In this paper, the chloroplast psbK-psbI intergenic spacers of 18 species of Dendrobium and their adulterants were amplified and sequenced, and then the sequence characteristics were analyzed. The sequence lengths of chloroplast psbK-psbI regions of Dendrobium ranged from 474 to 513 bp and the GC contents were 25.4%-27.6%. The variable sites were 71 while the informative sites were 46. The inter-specific genetic distances calculated by Kimura 2-parameter (K2P) of Dendrobium were 0.006 1-0.058 1, with an average of 0.028 4. The K2P genetic distances between Dendrobium species and Bulbophyllum odoratissimum were 0.093 2-0.120 4. The NJ tree showed that the Dendrobium species can be easily differentiated from each other and 6 samples of the inspected Dendrobium species were identified successfully through sequencing the psbK-psbI intergenic spacer. Therefore, the chloroplast psbK-psbI intergenic spacer can be used as a candidate marker to identify Dendrobium species and its adulterants.