[Transcriptome characterization of Ephedra sinica with 454 ESTs].

Using the latest 454 GS FLX platform and Titanium regent, a substantial expressed sequence tag (ESTs) dataset of Ephedra sinica was produced, and the profile of gene expression and function gene of which were investigated. A total of 48 389 reads with an average length of 373 bp were generated. These 454 reads were assembled into 18 801 unigenes, which were all 454 sequencing identified. A total number of 10 531 unigenes(56.0%) were annotated using BLAST searches (E-value≤1×10⁻5) against the Nr, Nt, TAIR, SwissProt and KEGG databases. With respect to genes related to ephedrine biosynthesis, 19 unigenes(encoding 9 enzymes) were found. A total of 97 putative genes encoding cytochrome P450s were also discovered. Data presented in this study will provide an important resource for the scientific community that is interested in the functional genomics and secondary metabolism of E. sinica.

[Cloning and bioinformatic analysis of PqERF1 gene in Panax quinquefolius].

ERF family transcription factor (TF) represented ethylene-responsive protein which harbored a conserved AP2 domain. After searching the plant transcription factor database, a total of 75 unigenes was found which contained AP2 domain from the transcriptome dataset of Panax quinquefolius L. One unique sequence of ERF transcript, named as PqERF1, was cloned with entire open reading frame of 933 base pairs (bp). Protein prediction result indicated that the gene was localized in nucleus and had a conserved AP2 domain. PqERF1 gene could be induced by methyl jasmonate (MeJA) which was consistent to the inducing profile of triterpene ginsenosides. InterproScan prediction indicated that PqERF1 was probably a pathogenesis-related gene. Sequence alignment and phylogenetic analysis demonstrated PqERF1 was with high identity and had relative close relationship to the NtERF4 (Nicotiana tabacum), PhERF12 (Petunia x hybrida) and DcERF1 (Daucus carota) which was related to plant defense, regulation of secondary metabolism and the flower senescence respectively. Therefore, the gene was likely involved in regulation of secondary metabolism, plant defense and physical processes which would provide gene resource for further study on secondary metabolite synthesis and molecular breeding of P. quinquefolius.

[Strategies of the study on herb genome program].

Herb Genome Program (HerbGP) includes a series of projects on whole genome sequencing (WGS) and post-genomics research of medicinal plants with unique secondary metabolism pathways or/and those of great medical and pharmaceutical importance. In this paper, we systematically discussed the strategy of HerbGP, from species selection, whole-genome sequencing, assembly and bioinformatics analysis, to postgenomics research. HerbGP will push study on Chinese traditional medicines into the front field of life science, by selecting a series of plants with unique secondary metabolism pathways as models and introducing "omics" methods into the research of these medicinal plants. HerbGP will provide great opportunities for China to be the leader in the basic research field of traditional Chinese medicine. HerbGP shall also have significant impacts on the R&D of natural medicines and the development of medicinal farming by analysis of secondary metabolic pathways and selection of cultivars with good agricultural traits.

EST analysis reveals putative genes involved in glycyrrhizin biosynthesis.

BACKGROUND: Glycyrrhiza uralensis is one of the most popular medicinal plants in the world and is also widely used in the flavoring of food and tobacco. Due to limited genomic and transcriptomic data, the biosynthetic pathway of glycyrrhizin, the major bioactive compound in G. uralensis, is currently unclear. Identification of candidate genes involved in the glycyrrhizin biosynthetic pathway will significantly contribute to the understanding of the biosynthetic and medicinal chemistry of this compound. RESULTS: We used the 454 GS FLX platform and Titanium regents to produce a substantial expressed sequence tag (EST) dataset from the vegetative organs of G. uralensis. A total of 59,219 ESTs with an average read length of 409 bp were generated. 454 ESTs were combined with the 50,666 G. uralensis ESTs in GenBank. The combined ESTs were assembled into 27,229 unique sequences (11,694 contigs and 15,535 singletons). A total of 20,437 unique gene elements representing approximately 10,000 independent transcripts were annotated using BLAST searches (e-value